0000000000011036

AUTHOR

Pekka Neittaanmäki

Block Based Deconvolution Algorithm Using Spline Wavelet Packets

This paper presents robust algorithms to deconvolve discrete noised signals and images. The idea behind the algorithms is to solve the convolution equation separately in different frequency bands. This is achieved by using spline wavelet packets. The solutions are derived as linear combinations of the wavelet packets that minimize some parameterized quadratic functionals. Parameters choice, which is performed automatically, determines the trade-off between the solution regularity and the initial data approximation. This technique, which id called Spline Harmonic Analysis, provides a unified computational scheme for the design of orthonormal spline wavelet packets, fast implementation of the…

research product

Laskennallisten tieteiden tutkimuksen ja koulutuksen kehittäminen

research product

On State Constrained Optimal Shape Design Problems

This paper is concerned with the following optimal design problem with constraints both on the state and on the control: $$MinimizeJ(y,u)$$ (P) subject to $$A\left( u \right)y + \partial \varphi \left( y \right) \mathrel\backepsilon Bu + f,$$ (1.1) $$y \in K,$$ (1.2) $$u \in {U_{ad}}.$$ (1.3)

research product

Tekstin automaattisesta tiivistämisestä

research product

Mixed-type circuits with distributed and lumped parameters as correct models for integrated structures

The technology of integrated circuits imposes upon their designers the need to deal with structures with distributed parameters. Figure 4.1 shows a schematic diagram of part of a digital integrated chip, consisting of an n MOS transistor with gate (G), drain (D) and source (S) as terminals, and its thin-film connection with the rest of the chip. This on-chip connection can be made by metals (Al, W), polycristaline silicon (polysilicon) or metal suicides (WSi 2 ). Alternative materials to oxide-passivated silicon substrates are saphire and gallium arsenide (Saraswat and Mohammadi [1982], Yuan et al. [1982], Passlack et al. [1990]).

research product

Numerical approach for signal delay in general distributed networks

The authors consider a general network with telegraph equations modelling distributed elements and having, additionally, nonlinear capacitors. A global asymptotic exponential stability of the solution is given. A simple computable upper bound of the delay time is given. Numerical examples illustrate the usefulness of the results. >

research product

Co-evolutionary coupling leads a way to a novel concept of R&D - Lessons from digitalized bioeconomy

Given the increasing role of research and development (R&D) in competitive markets in the digital economy while confronting the dilemma between R&D expansion and a productivity decline, transformation of the R&D model has become a crucial subject for global digital leaders. The authors of this paper postulate that neo open innovation harnessing the vigor of external innovation resources which then developed into a new concept of R&D that self-transforms during an R&D process initiated by Amazon by coupling with users. The authors further develop these postulates by proposing the embedding of a growth characteristic identical to biological coupling. An empirical analysis focusing on the fore…

research product

Uusi tieto ja osaaminen yliopistosta yhteiskuntaan : JYU Accelerator chain : KINO - Kansainvälisen innovaatio-osaamisen kehittäminen korkeakouluissa ja tutkimusorganisaatioissa : syksy 2016

research product

Tekoäly lääkitysturvallisuudessa

research product

Well-posed nonlinear problems in integrated circuits modeling

In this paper we study the problem (E) + (BC) + (IC) (see below) which represents a model for integrated circuits. We assume that the distributed parametersr(x) andc(x) are nonconstant, dielectric leakages depend on thex-coordinate as well as the voltage level, while the interconnecting multiport is nonlinear and possibly multivalued.

research product

On the construction of lusternik-schnirelmann critical values with application to bifurcation problems

An iterative method to construct Lusternik-Schnirelmann critical values is presented. Examples of its use to obtain numerical solutions to nonlinear eigenvalue problems and their bifurcation branches are given

research product

Kyberturvallisuuden ja big data-analyysin tutkimus ja opetus

research product

Sur les problèmes d'optimisation structurelle

We discuss existence theorems for shape optimization and material distribution problems. The conditions that we impose on the unknown sets are continuity of the boundary, respectively a certain measurability hypothesis. peerReviewed

research product

Static instability analysis for travelling membranes and plates interacting with axially moving ideal fluid

The out-of-plane instability of a moving plate, travelling between two rollers with constant velocity, is studied, taking into account the mutual interaction between the buckled plate and the surrounding, axially flowing ideal fluid. Transverse displacement of the buckled plate (assumed cylindrical) is described by an integro-differential equation that includes the centrifugal force, the aerodynamic reaction of the external medium, the vertical projection of membrane tension, and the bending force. The aerodynamic reaction is found analytically as a functional of the displacement. To find the critical divergence velocity of the moving plate and its corresponding buckling mode, an eigenvalue…

research product

Dynamic Behaviour of an Axially Moving Plate Undergoing Small Cylindrical Deformation Submerged in Axially Flowing Ideal Fluid

Abstract The out-of-plane dynamic response of a moving plate, travelling between two rollers at a constant velocity, is studied, taking into account the mutual interaction between the vibrating plate and the surrounding, axially flowing ideal fluid. Transverse displacement of the plate (assumed cylindrical) is described by an integro-differential equation that includes a local inertia term, Coriolis and centrifugal forces, the aerodynamic reaction of the external medium, the vertical projection of membrane tension, the bending resistance, and external perturbation forces. In the two-dimensional model thus set up, the aerodynamic reaction is found analytically as a functional of the cylindri…

research product

On the numerical solution of the distributed parameter identification problem

A new error estimate is derived for the numerical identification of a distributed parameter a(x) in a two point boundary value problem, for the case that the finite element method and the fit-to-data output-least-squares technique are used for the identifications. With a special weighted norm, we get a pointwise estimate. Prom the error estimate and also from the numerical tests, we find that if we decrease the mesh size, the maximum error between the identified parameter and the true parameter will increase. In order to improve the accuracy, higher order finite element spaces should be used in the approximations.

research product

The DevOps phenomena

research product

Topology of multiplex heterogeneous networks of Hodgkin-Huxley-type of models with bistability leading to stabilization stable equilibrium

The dynamics of a multiplex heterogeneous networks of oscillators is studied. Two types of very similar models based on the Hodgkin-Huxley formalism are used as the basic elements of the network: the first one demonstrates bursting oscillations; the second one manifests bistability between bursting oscillations and stable equilibrium. Multiplex networks were developed and investigated, assuming more active communication between models with bistability. Different topologies of the networks are studied. It is shown that in this case it is enough to have one element with bistability in the subnetworks in order to stabilize the equilibrium state in the entire network.

research product

Fixed domain approaches in shape optimization problems

This work is a review of results in the approximation of optimal design problems, defined in variable/unknown domains, based on associated optimization problems defined in a fixed ?hold-all? domain, including the family of all admissible open sets. The literature in this respect is very rich and we concentrate on three main approaches: penalization?regularization, finite element discretization on a fixed grid, controllability and control properties of elliptic systems. Comparison with other fixed domain approaches or, in general, with other methods in shape optimization is performed as well and several numerical examples are included.

research product

Computational stability of an initially radial solution of a growth/dissolution problem in a nonradial implementation

We consider a free boundary problem modelling the growth/dissolution of a crystal. The aim is to investigate the following question: Does the solution to the crystal growth problem posed in two dimensions with radially symmetric initial and boundary condition evolve as a radially symmetric solution?

research product

On the design of the optimal covering of an obstacle

We consider the problem of controlling the shape of the coincidence set in an obstacle problem. This so called packaging problem was introduced in

research product

On the Reliability of Error Indication Methods for Problems with Uncertain Data

This paper is concerned with studying the effects of uncertain data in the context of error indicators, which are often used in mesh adaptive numerical methods. We consider the diffusion equation and assume that the coefficients of the diffusion matrix are known not exactly, but within some margins (intervals). Our goal is to study the relationship between the magnitude of uncertainty and reliability of different error indication methods. Our results show that even small values of uncertainty may seriously affect the performance of all error indicators.

research product

Periodic Polynomial Splines

In this chapter, the spaces of periodic polynomial splines and the Spline Harmonic Analysis (SHA) in these spaces are briefly outlined. The stuff of this chapter is used for the design of periodic discrete-time splines and discrete-time-spline-based wavelets and wavelet packets. For a detailed description of the subject we refer to (Averbuch, Neittaanmaki and Zheludev, Spline and Spline Wavelet Methods with Applications to Signal and Image Processing, Springer, Berlin, 2014) [1]. Periodic polynomial splines provide an example of mixed discrete-continuous circular convolution.

research product

Stochastic Control Problems

The general theory of stochastic processes originated in the fundamental works of A. N. Kolmogorov and A. Ya. Khincin at the beginning of the 1930s. Kolmogorov, 1938 gave a systematic and rigorous construction of the theory of stochastic processes without aftereffects or, as it is customary to say nowadays, Markov processes. In a number of works, Khincin created the principles of the theory of so-called stationary processes.

research product

Fixed domain approaches in shape optimization problems with Dirichlet boundary conditions

Fixed domain methods have well-known advantages in the solution of variable domain problems including inverse interface problems. This paper examines two new control approaches to optimal design problems governed by general elliptic boundary value problems with Dirichlet boundary conditions. Numerical experiments are also included peerReviewed

research product

Tutkimusperustaiset interventiot osaksi uudistuvaa sosiaali- ja terveydenhuollon kehitysohjelmaa ja kansansairauksien ennaltaehkäisyä

Tekoäly puhuttaa ihmisiä jatkuvasti. Usein puheenaiheet liittyvät pelkoihin tekoälyn lisääntyvistä vaikutuksista, jotka ovat negatiivisia ihmisten kannalta. Pekka Neittaanmäki ja Karoliina Kaasalainen tarkastelevat artikkelissaan niitä mahdollisuuksia, joita tekoäly tarjoaa erityisesti ennalta ehkäisevän terveydenhuollon kehittämiseen. Erityiskohteina kirjoittajilla ovat mahdollisuudet tekoälysovellusten kansansairauksien hoidossa. Tekstissä on nostettu esiin myös monenlaisia esteitä tekoälyn soveltamiselle. Artikkelin aineisto pohjautuu kirjoittajien toteuttamaan Tekoäly ja terveydenhuolto Suomessa -hankkeeseen. peerReviewed

research product

Delineation of Malignant Skin Tumors by Hyperspectral Imaging

This chapter outlines a new non-invasive method for delineation of skin lesions such as lentigo maligna and lentigo maligna melanoma. The method is based on the analysis of hyperspectral (HS) images taken in vivo before surgical excision of the lesions. For this, characteristic features of the spectral signatures of diseased pixels and healthy pixels are extracted, which combine the intensities in a few selected wavebands with the coefficients of the wavelet frame transforms of the spectral curves. To reduce dimensionality and to reveal the internal structure of the datasets, the diffusion maps (DM) technique is applied. The averaged Nearest Neighbor and the Classification and Regression Tr…

research product

Terveydenhuollon alustat ja tekoäly

research product

Polynomial Smoothing Splines

Interpolating splines is a perfect tool for approximation of a continuous-time signal \(f(t)\) in the case when samples \(x[k]=f(k),\;k\in \mathbb {Z}\) are available. However, frequently, the samples are corrupted by random noise. In such case, the so-called smoothing splines provide better approximation. In this chapter we describe periodic smoothing splines in one and two dimensions. The SHA technique provides explicit expression of such splines and enables us to derive optimal values of the regularization parameters.

research product

Co-evolution of three mega-trends nurtures un-captured GDP – Uber's ride-sharing revolution

Uber used a disruptive business model driven by digital technology to trigger a ride-sharing revolution. The institutional sources of the company’s platform ecosystem architecture were analyzed to explain this revolutionary change. Both an empirical analysis of a co-existing development trajectory with taxis and institutional enablers that helped to create Uber’s platform ecosystem were analyzed. The analysis identified a correspondence with the “two-faced” nature of ICT that nurtures un-captured GDP. This two-faced nature of ICT can be attributed to a virtuous cycle of decline in prices and an increase in the number of trips. We show that this cycle can be attributed to a self-propagating …

research product

Travelling Strings, Beams, Panels, Membranes and Plates

In this chapter, we will introduce in a general manner some of the most common models for axially travelling materials, which will be used in the rest of the book. We will introduce the linear models of travelling strings, panels, and plates. It will be assumed that the material is thin, i.e. its planar dimensions are much larger than its thickness. We will work in the small displacement regime, that is, with linear models approximating the behaviour of the system near the trivial equilibrium. As is well known in the theory of elasticity, this approximation allows for a decoupling of the in-plane and out-of-plane components in the dynamics of the system. We will concentrate on small out-of-…

research product

Deconvolution by Regularized Matching Pursuit

In this chapter, an efficient method that restores signals from strongly noised blurred discrete data is presented. The method can be characterized as a Regularized Matching Pursuit (RMP), where dictionaries consist of spline wavelet packets. It combines ideas from spline theory, wavelet analysis and greedy algorithms. The main distinction from the conventional matching pursuit is that different dictionaries are used to test the data and to approximate the solution. In addition, oblique projections of data onto dictionary elements are used instead of orthogonal projections, which are used in the conventional Matching Pursuit (MP). The slopes of the projections and the stopping rule for the …

research product

A variational inequality approach to constrained control problems

research product

The Impact of a Finite Waveguide Work Function on Resonant Tunneling

To describe electron transport in a waveguide, we assume that the electron wave functions vanish at the waveguide boundary. This means that, being in the waveguide, an electron can not cross the waveguide boundary because of the infinite potential barrier. In reality, the assumption has never been fulfilled: generally, electrons can penetrate through the waveguide boundary and go some distance away from the waveguide. Therefore, we have to clarify how this phenomenon affects the resonant tunneling.

research product

Tekoäly Japanin terveydenhuollossa

research product

Direct Numerical Methods for Optimal Control Problems

Development of interior point methods for linear and quadratic programming problems occurred during the 1990’s. Because of their simplicity and their convergence properties, interior point methods are attractive solvers for such problems. Moreover, extensions have been made to more general convex programming problems.

research product

Numerical methods for nonlinear inverse problems

AbstractInverse problems of distributed parameter systems with applications to optimal control and identification are considered. Numerical methods and their numerical analysis for solving this kind of inverse problems are presented, main emphasis being on the estimates of the rate of convergence for various schemes. Finally, based on the given error estimates, a two-grid method and related algorithms are introduced, which can be used to solve nonlinear inverse problems effectively.

research product

Innovaatiot ja yrittäjyys osana yliopisto-opintoja : opiskelijakyselyn tulokset

research product

A parallel splitting up method and its application to Navier-Stokes equations

A parallel splitting-up method (or the so called alternating-direction method) is proposed in this paper. The method not only reduces the original linear and nonlinear problems into a series of one dimensional linear problems, but also enables us to compute all these one dimensional linear problems by parallel processors. Applications of the method to linear parabolic problem, steady state and nonsteady state Navier-Stokes problems are given. peerReviewed

research product

Shape optimization in contact problems with friction

research product

Errors Arising in Computer Simulation Methods

The goal of this introductory chapter is to discuss in general terms different classes of errors arising in computer simulation methods and to direct the reader to the chapters and sections of the book where these errors are analyzed. Moreover, we describe the error estimation methodology applied in this book.

research product

Operationalization of un-captured GDP - Innovation stream under new global mega-trends

With the understanding that current ICT-driven global development depends on a trend shifting from traditional co-evolution of computer-initiated ICT, captured GDP, and economic functionality to new co-evolution of the Internet, un-captured GDP, and supra-functionality beyond economic value, the following hypothetical view was postulated: The disparity between the world's ICT leader countries with respect to happiness/welfare amidst great stagnation (Finland) or conspicuous economic growth (Singapore) can be attributed to the difference of the state in the above shifting trends. The foregoing hypothetical view was demonstrated on the basis of an empirical analysis measuring dependency on un…

research product

A Fixed Domain Approach in Shape Optimization Problems with Neumann Boundary Conditions

Fixed domain methods have well-known advantages in the solution of variable domain problems, but are mainly applied in the case of Dirichlet boundary conditions. This paper examines a way to extend this class of methods to the more difficult case of Neumann boundary conditions.

research product

Suomen pelialan koulutuksen kartoitus 2014

research product

Mesh-adaptive methods for viscous flow problem with rotation

In this paper, new functional type a posteriori error estimates for the viscous flow problem with rotating term are presented. The estimates give guaranteed upper bounds of the energy norm of the error and provide reliable error indication. We describe the implementation of the adaptive finite element methods (AFEM) in the framework of the functional type estimates proposed. Computational properties of the estimates are investigated on series of numerical examples.

research product

On finite element approximation of the gradient for solution of Poisson equation

A nonconforming mixed finite element method is presented for approximation of ?w with Δw=f,w| r =0. Convergence of the order $$\left\| {\nabla w - u_h } \right\|_{0,\Omega } = \mathcal{O}(h^2 )$$ is proved, when linear finite elements are used. Only the standard regularity assumption on triangulations is needed.

research product

Laskennallisten tieteiden kansallinen kehittäminen 2009 : nykytilan kartoitus

research product

On the existence of optimal shapes in contact problems : perfectly plastic bodies

research product

On Bifurcation Analysis of Implicitly Given Functionals in the Theory of Elastic Stability

In this paper, we analyze the stability and bifurcation of elastic systems using a general scheme developed for problems with implicitly given functionals. An asymptotic property for the behaviour of the natural frequency curves in the small vicinity of each bifurcation point is obtained for the considered class of systems. Two examples are given. First is the stability analysis of an axially moving elastic panel, with no external applied tension, performing transverse vibrations. The second is the free vibration problem of a stationary compressed panel. The approach is applicable to a class of problems in mechanics, for example in elasticity, aeroelasticity and axially moving materials (su…

research product

Resonant Tunneling in 2D Waveguides in Magnetic Field

Chapter 7 presents an asymptotic and numerical studies of resonant tunneling in a two-dimensional waveguide with two-narrows in magnetic field. It is supposed that the electron energy is between the first and the second thresholds.

research product

SOTE-toimintojen tehostaminen IT:n avulla : kehittämispotentiaali ja toimenpideohjelma

research product

A New Perspective on the Textile and Apparel Industry in the Digital Transformation Era

The textile and apparel (fashion) industry has been influenced by developments in societal socio-cultural and economic structures. Due to a change in people’s preferences from economic functionality to supra-functionality beyond economic value, the fashion industry is at the forefront of digitalization. The growing digitalization in the fashion industry corresponds to digital fashion, which can satisfy the rapid shift in consumers’ preferences. This paper explores the evolving con-cept of innovations in digital fashion in the textile and apparel industry. Specifically, it centers on the evaluation of Amazon’s digital fashion initiatives, which have made the platform the Un…

research product

CO-Evolution Between CCC-Driven Cash Flow Management and Transformation of R&D : Amazon’S Endeavor

Amazon became the world R&D leader in 2017 by rapidly increasing R&D investment. The company’s extremely large amount of R&D funds is the result of an ample free cash flow generated by sophisticated cash conversion cycle (CCC) management. Increased R&D induced business advancement and lean cost structure construction leading to further increase in cash flow which has stimulated interaction between vendors, customers, and Amazon via the Amazon marketplace. Activated interaction accelerated CCC advancement, a subsequent free cash flow increase, and user-driven innovation, thus accelerated the transformation of routine and periodic alteration activities into significant improvement simultaneou…

research product

A boundary controllability approach in optimal shape design problems

We indicate a formulation of optimal shape design problems as boundary control problems, based on some approximate controllability-type results. Numerical examples and a comparison with the standard method are included.

research product

Stability of Axially Moving Plates

This chapter focuses on the stability analysis of axially moving materials, in the context of two-dimensional models. There are many similarities with the classical stability analysis of structures, such as the buckling analysis of plates. However, the presence of axial motion introduces inertial effects to the model. We consider the stability of an axially moving elastic isotropic plate travelling at a constant velocity between two supports and experiencing small transverse vibrations. We investigate the stability of the plate using an analytical approach. We also look at elastic orthotropic plates, and an elastic isotropic plate subjected to an axial tension distribution that varies in th…

research product

Suomen tekoälytuettu digitaalinen SOTE- ja koulujärjestelmä 2025

Koulut ovat siirtyneet etäopetukseen lähikuukausien ajaksi sekä Suomessa että ympäri maailmaa. UNESCO:n seurannan mukaan perusasteen, toisen asteen ja korkea-asteen koulutus on 23.4. päivitetyn tiedon mukaan pysäytetty joko kokonaan tai osittain 191 maassa. COVID-19 virus vaikeuttaa yli 1,6 miljardin nuoren opiskelua. Jo ennen virusepidemiaa 260 miljoonaa lasta globaalisti oli ilman koulutusta. Kriisin odotetaan syventävän globaalia oppimiskriisiä. Kiinnostus Suomen digitaalisia koulutusratkaisuja kohtaan on globaali. Meneillään olevasta etäopetusperiodista pitää kerätä hyvät ja huonot kokemukset. Niiden pohjalta Suomen tulee rakentaa kaikkia koulutusasteita koskeva kansallinen digitaalinen…

research product

A posteriori error estimates for time-dependent reaction-diffusion problems based on the Payne-Weinberger inequality

We consider evolutionary reaction-diffusion problem with mixed Dirichlet--Robin boundary conditions. For this class of problems, we derive two-sided estimates of the distance between any function in the admissible energy space and exact solution of the problem. The estimates (majorants and minorants) are explicitly computable and do not contain unknown functions or constants. Moreover, it is proved that the estimates are equivalent to the energy norm of the deviation from the exact solution.

research product

A linear approach for the nonlinear distributed parameter identification problem

In identifying the nonlinear distributed parameters we propose an approach, which enables us to identify the nonlinear distributed parameters by just solving linear problems. In this approach we just need to identify linear parameters and then recover the nonlinear parameters from the identified linear parameters. An error estimate for the finite element approximation is derived. Numerical tests are also presented.

research product

Sensitivity analysis for optimal shape design problems

Various methods for performing the sensitivity analysis in solving optimal shape design problems are outlined. The methods are illustrated in detail in the finite setting of a unilateral boundary value problem of the Dirichlet-Signorini type. The methods are compared in several numerical examples.

research product

Mixed Probabilistic-Guaranteed Optimal Design

This chapter deals with the mixed probabilistic-guaranteed approach to optimal design of quasi-brittle membrane shells. Special attention is devoted to different problem formulations and analytical methods for their solution. Optimal thickness distributions are presented for various axisymmetric membrane shells. The presentation follows research results of [BRS03b].

research product

Dependency on un-captured GDP as a source of resilience beyond economic value in countries with advanced ICT infrastructure: Similarities and disparities between Finland and Singapore

Abstract The majority of countries with advanced information and communication technology (ICT) infrastructure have been experiencing extended stagnation due to an “embedded” trap in ICT advancement. However, certain countries have been able to sustain a high level of ICT- driven global competitiveness. This suggests that in these contexts there is resilience beyond economic value. Finland and Singapore can be considered countries of resilience with respect to ICT-driven global competitiveness because of their continued GDP growth despite the recession. While both countries share significant similarities including institutional strength in ICT, they demonstrate noteworthy disparities in the…

research product

Nonstationary heat conduction in a stator

In this chapter we describe a method for computing the 3d nonstationary temperature field in the lamination pack of a stator of a synchronous or asynchronous (induction) motor with a centrifugal, meander or chamber ventilation (see [Křižek, Preiningerova]). The stator of a motor has quite a complicated geometrical form. Moreover, it consists of anisotropic materials which have very different heat conductivities, e.g., 332.8 [W/mK] for copper wires and 0.2 [W/mK] for their insulations. This causes big jumps in coefficients of the appropriate heat conduction equation, and is the main source of numerical difficulties in practical calculations.

research product

Periodic Discrete and Discrete-Time Splines

Periodic discrete splines with different periods and spans are introduced in Sect. 3.4 of Volume I (Averbuch, Neittaanmaki and Zheludev, Spline and Spline Wavelet Methods with Applications to Signal and Image Processing, Springer, Berlin, 2014) [2]. In this chapter, we regard periodic discrete splines as a base for the design of periodic discrete-time wavelets, wavelet packets and wavelet frames. Therefore, only the discrete splines whose spans are 2 are outlined. These discrete splines are linear combinations of the discrete B-splines. So also, the so-called discrete-time splines are discussed in the chapter that are linear combinations of the discrete-time B-splines. The discrete-time B-s…

research product

Keski-Suomesta digikoulutuksen johtava maakunta : esiselvitys ja Master plan luonnos

Tavoitteena on, että koko Keski-Suomessa siirrytään vuoteen 2019 mennessä digitaaliseen koulutusjärjestelmään kaikilla koulutustasoilla: sekä yleissivistävässä ja ammatillises- sa koulutuksessa että korkeakoulutasoisessa koulutuksessa. Suomeen luodaan ensimmäisenä maailmassa keskitetyillä IT-järjestelmillä tuetettu peruskoulu ja lukio. Toiminnanohjaus ja materiaalit hoidetaan keskitetyiltä palvelimilta kullakin koulutusasteella. Digitaalisen koulujärjestelmän (Smart Education Finland) perusajatuksena on, että koko yleissivistävä koulutus voitaisiin tuottaa uuden sukupolven tietoverkoissa samanlaisena ja tasa-arvoisena kaikille. Jokainen oppilas saisi käyttöönsä henkilökohtaisen työaseman, j…

research product

On optimal shape design of systems governed by mixed Dirichlet-Signorini boundary value problems

research product

Optimal Shape Design in Contact Problems

From the mathematical point of view, optimal shape design (or optimum design, optimization of the domain, structural optimization) is a branch of the calculus of variations and especially of optimal control where study is devoted to the problem of finding the optimal shape for an object. In an optimal shape design process the objective is to optimize certain criteria involving the solution of a partial differential equation with respect to its domain of definition, [2, 3, 5].

research product

On the limit velocity and buckling phenomena of axially moving orthotropic membranes and plates

In this paper, we consider the static stability problems of axially moving orthotropic membranes and plates. The study is motivated by paper production processes, as paper has a fiber structure which can be described as orthotropic on the macroscopic level. The moving web is modeled as an axially moving orthotropic plate. The original dynamic plate problem is reduced to a two-dimensional spectral problem for static stability analysis, and solved using analytical techniques. As a result, the minimal eigenvalue and the corresponding buckling mode are found. It is observed that the buckling mode has a shape localized in the regions close to the free boundaries. The localization effect is demon…

research product

Automatic Secondary Cooling Control for the Continuous Casting Process of Steel

Two simulation models for finding the optimal secondary cooling strategy in continuous casting process are presented. The first one is a two-dimensional off-line model for optimizing steady state casting operation. The second one is a one-dimensional model which can be used for simulating casting operation in real-time during varying casting conditions.

research product

Arjen mobiilipalvelut -hankkeen oppimisen ja hyvinvoinnin mobiiliratkaisut

research product

Cubic Local Splines on Non-uniform Grid

In this chapter, two types of local cubic splines on non-uniform grids are described: 1. The simplest variation-diminishing splines and 2. The quasi-interpolating splines. The splines are computed by a simple fast computational algorithms that utilizes a relation between the splines and cubic interpolation polynomials. Those splines can serve as an efficient tool for real-time signal processing. As an input, they use either clean or noised arbitrarily-spaced samples. On the other hand, the capability to adapt the grid to the structure of an object and minimal requirements to the operating memory are great advantages for off-line processing of signals and multidimensional data arrays.

research product

Biorthogonal Wavelet Transforms

Wavelets in the polynomial and discrete spline spaces were introduced in Chaps. 8 and 10, respectively. In both cases, the wavelets’ design and implementation of the transforms were associated with perfect reconstruction (PR) filter banks. In this chapter, those associations are discussed in more detail. Biorthogonal wavelet bases generated by PR filter banks are investigated and a few examples of compactly supported biorthogonal wavelets are presented. Conditions for filters to restore and annihilate sampled polynomials are established (discrete vanishing moment property). In a sense, the material of this chapter is introductory to Chap. 12, where splines are used as a source for (non-spli…

research product

A SOLUTION TO THE DILEMMA BETWEEN R&D EXPANSION AND THE PRODUCTIVITY DECLINE: LESSONS FROM THE R&D MODELS IN AMAZON AND FINLAND

As a consequence of the two-faced nature of information and communication technology (ICT), a majority of ICT leaders have been confronting the critical problem of a dilemma between R&D expansion and productivity decline in the digital economy. However, Amazon has been able to accomplish a skyrocketing increase in R&D and market capitalization. Finland has also accomplished balanced advancement not only of welfare but also economic resurgence. This paper attempted to elucidate the miracle of two ICT leaders. By means of a comparative empirical analysis of respective development trajectories, the sources of their success were analyzed thereby the comparative advantage and disadvantag…

research product

Tekoälypohjaisten teknologioiden testaus prototyyppisovelluksilla

research product

Digitaalitalouden kehityksen aiheuttamat verotusongelmat

research product

Amazon's initiative transforming a non-contact society : Digital disruption leads the way to stakeholder capitalization

Contrary to the decisive role of R&D centered on information and communication technology (ICT) in the digital economy, its excessive expansion has resulted in declining productivity due to the two-faced nature of ICT. Consequently, the novel concept emerges of innovation that maintains sustainable growth by harnessing the vigor of soft innovation resources (SIRs). Pioneering endeavors can be observed at the forefront of the global ICT leaders. World R&D leader Amazon has been harnessing the power of users that seek SIRs. This functions as a virtuous cycle, leading to the transformation of R&D by fusing a unique R&D system with a sophisticated financing system. With this orchestration, Amaz…

research product

A delay time bound for distributed parameter circuits with bipolar transistors

We prove here a stability theorem concerning a parabolic system of equations with non-linear boundary conditions that governs the behaviour of a class of networks in which the bipolar transistors operating under large-signal conditions are interconnected with reg-lines modelled by telegraph equations

research product

Consequences of the Digital Economy : Transformation of the Growth Concept

The digital economy is transforming the traditional concepts of economic growth.The recent reversal trend in GDP growth of ICT leaders can be attributed to effective utilization of soft innovation resources in Finland and adherence to traditional resources in Singapore.Confronting a productivity decline in the digital economy, global information and communication technology (ICT) leaders are transforming business models into those with uncaptured GDP creation. This can be attributed tothe harnessing soft innovation resourcesagainst a productivity decline. This in turn activates a self-propagating function and induces supra-functionality beyond economic value corresponding to a shift in peop…

research product

Consolidated challenge to social demand for resilient platforms : Lessons from Uber's global expansion

Many in the industry see the ride-sharing company Uber as the significant advancement through information and communication technology (ICT) particularly of the digital service platform and sharing economy. Uber has been exploring the new frontier of the ICT-driven disruptive business model (IDBM) and succeeded in its global expansion to over 479 cities in more than 75 countries worldwide in June of 2016. Such rapid expansion provides constructive insights regarding the significance of IDBM, not only in transportation but also in almost all other business fields. While at the same time Uber's legal battles in some cities around the world raise a serious question regarding the rationale of I…

research product

Harnessing Women’s Potential as a Soft Engine for Growth : Lessons from Contrasting Trajectories between Finland and Japan for Growing Economies

Harnessing the vigor of women’s potential is essential for inclusive economic growth in a digital economy moving toward aging society. This can be a soft engine for sustainable growth substitutable for costly hard investment. While there exists explicit evidence of a virtual cycle between economic growth and gender balance improvement, emerging countries cannot afford to overcome the constraints of low income. Given the foregoing, this paper analyzed possible co-evolution between economic growth, gender balance improvement and digital innovation initiated by information and communication technology (ICT) advancement. Using a unique dataset representing the state of gender balance improvemen…

research product

On numerical simulation of the continuous casting process

In this paper a steady-state nonlinear parabolic-type model, which simulates the multiphase heat transfer during solidification in continuous casting, is presented. An enthalpy formulation is used and we apply a FE-method in space and an implicit Euler method in time. A detailed solution algorithm is presented. We compute the temperature distributions in the strand when the boundary conditions (mold/spray cooling) on the strand surface are known. The numerical model gives thereby a good basis for the testing of new designs of continuous-casting machines. An application of the model to continuous casting of billets is presented.

research product

The transformation of R&D into neo open innovation- a new concept in R&D endeavor triggered by amazon

Amazon was the world's top Research and Development (R&D) firm in 2017. Its R&D investment was double that of 2015, five times that of 2012, and ten times that of 2011. Such a rapid and notable increase in R&D investment has raised the question of a new R&D definition and focus in the digital economy, which Amazon insists includes both “routine or periodic alterations” (traditionally classified as non-R&D) and “significant improvement” (classified as R&D). Using an empirical analysis of Amazon's R&D model as a system, this paper attempts to provide a convincing answer to this question. It has been identified that Amazon, which is based on R&D as a culture, has been promoting companywide exp…

research product

IBM-teknologioiden hyödyntäminen terveydenhuollossa

research product

Suomen koulutus- ja tutkintojärjestelmää tulee uudistaa ja perustaa tiede- ja teknologiaministeri

research product

Trusted Computing and DRM

Trusted Computing is a special branch of computer security. One branch of computer security involves protection of systems against external attacks. In that branch we include all methods that are used by system owners against external attackers, for example Firewalls, IDS, IPS etc. In all those cases the system owner installs software that uses its own means to determine if a remote user is malicious and terminates the attack. (Such means can be very simple such as detecting signatures of attacks or very complex such as machine learning and detecting anomalies in the usage pattern of the remote user). Another branch of attacks requires protection by the system owner against internal users. …

research product

Parameter Rating by Diffusion Gradient

Anomaly detection is a central task in high-dimensional data analysis. It can be performed by using dimensionality reduction methods to obtain a low-dimensional representation of the data, which reveals the geometry and the patterns that exist and govern it. Usually, anomaly detection methods classify high-dimensional vectors that represent data points as either normal or abnormal. Revealing the parameters (i.e., features) that cause detected abnormal behaviors is critical in many applications. However, this problem is not addressed by recent anomaly-detection methods and, specifically, by nonparametric methods, which are based on feature-free analysis of the data. In this chapter, we provi…

research product

Tohtoreita enemmän yrityksiin ja johtopaikoille

research product

Wavelet Frames Generated by Spline Based p-Filter Banks

This chapter presents a design scheme to generate tight and so-called semi-tight frames in the space of discrete-time periodic signals. The frames originate from oversampled perfect reconstruction periodic filter banks. The filter banks are derived from discrete-time and discrete periodic splines. Each filter bank comprises one linear phase low-pass filter (in most cases interpolating) and one high-pass filter, whose magnitude response mirrors that of a low-pass filter. In addition, these filter banks comprise a number of band-pass filters. In this chapter, frames generated by four-channel filter banks are briefly outlined (see Chap. 17 in [2] for details) and tight frames generated by six-…

research product

Shape Optimization in Contact Problems. 1. Design of an Elastic Body. 2. Design of an Elastic Perfectly Plastic Body

The optimal shape design of a two dimensional body on a rigid foundation is analyzed. The problem is how to find the boundary part of the body where the unilateral boundary conditions are assumed in such a way that a certain energy integral (total potential energy, for example) will be minimized. It is assumed that the material of the body is elastic. Some remarks will be given concerning the design of an elastic perfectly plastic body. Numerical examples will be given.

research product

Yhteiskunnan digimurros

“The biggest part of our digital transformation is changing the way we think.” — Simeon Preston, CEO of International Markets unit in Bupa. Yhteiskunnan digimurros on laaja termi, joka kuvaa kokonaisvaltaista muutostilaa. Digimurros koskettaa lähes kaikkia elämän osa-alueita tämän päivän länsimaisessa kehittyneessä valtiossa. Digimurroksesta on puhuttu paljon muun muassa talouden ja teollisuuden konteksteissa, mutta on perusteltua sanoa, että kyseessä on yhteiskunnan kannalta paljon laajamittaisempi termi. Puhumme myös usein digitalisoituneesta yhteiskunnasta, mutta tämäkään ei itsessään ole riittävä termi ottamaan huomioon digitalisaation luomia muutoksia. Digimurros on enemmän kuin kokoel…

research product

Digitaalisten interventioiden vaikuttavuus ja kustannusvaikuttavuus kansansairauksien ennaltaehkäisyssä ja omahoidossa

research product

Jyväskylän pelialan tilannekatsaus

research product

Optimization and analysis of processes with moving materials subjected to fatigue fracture and instability

We study systems of traveling continuum modeling the web as a thin elastic plate of brittle material, traveling between a system of supports at a constant velocity, and subjected to bending, in-plane tension and small initial cracks. We study crack growth under cyclic in-plane tension and transverse buckling of the web analytically. We seek optimal in-plane tension that maximizes a performance vector function consisting of the number of cycles before fracture, the critical velocity and process effectiveness. The present way of applying optimization in the studies of fracture and stability is new and affords an analytical tool for process analysis. peerReviewed

research product

Selected Topics from Functional and Convex Analysis

research product

Fictitious Domain Methods for the Numerical Solution of Two-Dimensional Scattering Problems

Fictitious domain methods for the numerical solution of two-dimensional scattering problems are considered. The original exterior boundary value problem is approximated by truncating the unbounded domain and by imposing a nonreflecting boundary condition on the artificial boundary. First-order, second-order, and exact nonreflecting boundary conditions are tested on rectangular and circular boundaries. The finite element discretizations of the corresponding approximate boundary value problems are performed using locally fitted meshes, and the discrete equations are solved with fictitious domain methods. A special finite element method using nonmatching meshes is considered. This method uses …

research product

Solving some optimal control problems using the barrier penalty function method

In this paper we present a new approach to solve the two-level optimization problem arising from an approximation by means of the finite element method of optimal control problems governed by unilateral boundary value problems. The minimized functional depends on control variables and state variables x. The latter are the optimal solution of an auxiliary quadratic programming problem, whose parameters depend on u.

research product

Lumped parameter approach of nonlinear networks with transistors

In this chapter we study the lumped parameter modelling of a large class of circuits composed of bipolar transistors, junction diodes and passive elements (resistors, capacitors, inductors). All these elements are nonlinear: the semiconductor components are modelled by “large signal” equivalent schemes, the capacitors and inductors have monotone characteristics while the resistors can be included in a multiport which also has a monotone description.

research product

Dissipative operators and differential equations on Banach spaces

If we consider the initial value problem Inline Equation $$x'(t) = f(t,x(t)),{\text{ }}x(0) = {x_0}$$ on the real line, it is well known that one—sided bounds like Inline Equation $$\left[ {f(t,x) - f\left( {t,y} \right)} \right]\left( {x - {\text{y}}} \right) \leqslant \omega {\left( {x - y} \right)^2}$$ give much better information about the behaviour of solutions than the Lipschitz- type estimates Inline Equation $$ \left| {f\left( {t,x} \right) - f\left( {t,y} \right)} \right| \leqslant L\left| {x - y} \right|,$$ because ω, unlike L, may be negative.

research product

New approach to numerical computation of the eigenfunctions of the continuous spectrum of three-particle Schrödinger operator: I. One-dimensional particles, short-range pair potentials

Basing on analogy between the three-body scattering problem and the diffraction problem of the plane wave (for the case of the short range pair potentials) by the system of six half transparent screens, we presented a new approach to the few-body scattering problem. The numerical results have been obtained for the case of the short range nonnegative pair potentials. The presented method allows a natural generalization to the case of the long range pair potentials.

research product

Rinnakkaislaskenta osittaisdifferentiaaliyhtälöiden numeerisessa ratkaisemisessa

research product

Asymptotic and Numerical Studies of Resonant Tunneling in 2D-Waveguides for Electrons of Small Energy

Chapter 5 is devoted to asymptotic studies of electron resonant tunneling in a two-dimensional waveguide with two narrows. The narrow diameter plays the role of a small parameter. The asymptotics of basic characteristics of resonant tunneling are presented for electrons with energy between the first and the second thresholds. Moreover, the asymptotics results are compared with numerical ones obtained by approximate calculation of the scattering matrix.

research product

Informaatioteknologia ja tekoäly tukena mielenterveyspalveluissa

Etenkin nuorten ikäryhmien mielenterveyden häiriöt ovat yleistyneet nopeasti viimeisten kymmenen vuoden aikana. Väestön fyysinen terveys on monilla mittareilla katsottuna aikaisempaa parempi, mutta ikärakenteen muuttuessa hoitoa tarvitsevien kokonaismäärä kasvaa. Mielenterveyspalveluihin tarvitaan lisää resursseja samalla kun työvoiman määrä vähenee. Tässä artikkelissa tarkastellaan informaatioteknologian ja tekoälyn mahdollisuuksia ennaltaehkäisevien mielenterveyspalveluiden kehittämisessä. Odotukset teknologian hyödyistä ovat korkealla, mutta tutkittua tietoa digitaalisten mielenterveyspalveluiden tavoittavuudesta, hyväksyttävyydestä ja vaikuttavuudesta tarvitaan lisää. nonPeerReviewed

research product

The time-harmonic Maxwell equations

In this chapter we shall see that the solution of the time-harmonic Maxwell equations with real coefficients can be transformed to time independent partial differential equations with complex coefficients. Then we introduce a finite element approximation proposed in [Křižek, Neittaanmaki, 1989]. A similar technique is analyzed in [Křižek, Neittaanmaki, 1984b], [Monk, 1992a] (for fully time dependent problems see, e.g., [Monk 1992b,c]).

research product

Optimization of the domain in elliptic variational inequalities

This paper is concerned with a nonsmooth shape optimization problem for the Signorini unilateral boundary-value problem. The necessary optimality conditions are derived. The results of computations are presented.

research product

A posteriori error identities for nonlinear variational problems

A posteriori error estimation methods are usually developed in the context of upper and lower bounds of errors. In this paper, we are concerned with a posteriori analysis in terms of identities, i.e., we deduce error relations, which holds as equalities. We discuss a general form of error identities for a wide class of convex variational problems. The left hand sides of these identities can be considered as certain measures of errors (expressed in terms of primal/dual solutions and respective approximations) while the right hand sides contain only known approximations. Finally, we consider several examples and show that in some simple cases these identities lead to generalized forms of the …

research product

Travelling Panels Interacting with External Flow

This chapter is devoted to the analysis of the travelling panel, submerged in axially flowing fluid. In order to accurately model the dynamics and stability of a lightweight moving material, the interaction between the material and the surrounding air must be taken into account somehow. The light weight of the material leads to the inertial contribution of the surrounding air to the acceleration of the material becoming significant. In the small displacement regime, the geometry of the vibrating panel is approximately flat, and hence flow separation is unlikely. We will use the model of potential flow for the fluid. The approach described in this chapter allows for an efficient semi-analyti…

research product

Informaatioteknologian tiedekunnan tutkimus- ja koulutusstrategia : White Paper

research product

Weighted Sobolev spaces and exterior problems for the Helmholtz equation

Weighted Sobolev spaces are used to settle questions of existence and uniqueness of solutions to exterior problems for the Helmholtz equation. Furthermore, it is shown that this approach can cater for inhomogeneous terms in the problem that are only required to vanish asymptotically at infinity. In contrast to the Rellich–Sommerfeld radiation condition which, in a Hilbert space setting, requires that all radiating solutions of the Helmholtz equation should satisfy a condition of the form ( ∂ / ∂ r − i k ) u ∈ L 2 ( Ω ) , r = | x | ∈ Ω ⊂ R n , it is shown here that radiating solutions satisfy a condition of the form ( 1 + r ) − 1 2 ( ln ( e + r ) ) − 1 2 δ u ∈ L 2 ( Ω ) , 0 < δ < 1 2 …

research product

Discrete Periodic Spline Wavelets and Wavelet Packets

Similarly to periodic polynomial splines, existence of the set of embedded discrete periodic splines spaces \(\varPi [N]= \fancyscript{S}_{[0]}\supset {}^{2r} \fancyscript{S}_{[1]}\supset \cdots \supset {}^{2r} \fancyscript{S}_{[m]}\cdots \), combined with the DSHA provides flexible tools for design and implementation of wavelet and wavelet packet transforms. As in the polynomial case, all the calculations consist of fast direct and inverse Fourier transforms (FFT and IFFT, respectively) and simple arithmetic operations. Raising the splines order does not increase the computation complexity.

research product

Parallel finite element splitting-up method for parabolic problems

An efficient method for solving parabolic systems is presented. The proposed method is based on the splitting-up principle in which the problem is reduced to a series of independent 1D problems. This enables it to be used with parallel processors. We can solve multidimensional problems by applying only the 1D method and consequently avoid the difficulties in constructing a finite element space for multidimensional problems. The method is suitable for general domains as well as rectangular domains. Every 1D subproblem is solved by applying cubic B-splines. Several numerical examples are presented.

research product

On One Identification Problem in Linear Elasticity

In practice we meet problems, when having the solution of partial differential equation, we want to discover parts in the domain of its definition where the solution has some specific properties. In [1] and [2] the problem of identification of a curve φ, lying inside of Ω such that the flux \(\int{_{\varphi }}\frac{\partial u}{\partial n}ds\) is maximal has been studied, where u is the solution of mixed—boundary value problem for Laplacian operator.

research product

A Unified Approach to Measuring Accuracy of Error Indicators

In this paper, we present a unified approach to error indication for elliptic boundary value problems. We introduce two different definitions of the accuracy (weak and strong) and show that various indicators result from one principal relation. In particular, this relation generates all the main types of error indicators, which have already gained high popularity in numerical practice. Also, we discuss some new forms of indicators that follow from a posteriori error majorants of the functional type and compare them with other indicators. Finally, we discuss another question related to accuracy of error indicators for problems with incompletely known data.

research product

A thermoelastic instability problem for axially moving plates

Problems of stability and deformation of a moving web, traveling between a system of rollers at a constant velocity are considered. The plate is subjected to a combined thermomechanical loading, including pure mechanical in-plane tension and also centripetal forces. Thermal strains corresponding to thermal tension and bending of the plate are accounted for. The problem of out-of-plane thermomechanical divergence (buckling) is reduced to an eigenvalue problem, which is studied analytically.

research product

Hyvinvointialan uudet toimintamallit ja palvelukonseptit -hankkeen tulokset ja kehittämisehdotukset

research product

Steady-state radiation heat transfer problem

In Section 8.2, we shall see that the steady-state radiative heat transfer problem can be transformed to minimization of a smooth nonquadratic functional J over a convex and closed subset of a Banach space V. To this end we firstly shortly recall some basic definitions concerning differentiability of J, because these sometimes differ in the literature.

research product

Matematiikan, fysiikan ja kemian maisteritutkinnot ja auskultointi 2010-luvulla

research product

Travelling Panels Made of Viscoelastic Material

In this chapter, our focus is to analyse the behaviour of moving panels using viscoelastic materials. As the reader will have noticed, all the models discussed in previous chapters have concerned the case of a purely elastic material. The deformation of an elastic material depends only on the applied forces; it has no explicit time dependence. Paper, however, is a more complicated material: it is viscoelastic. In addition to elastic properties, it has also time-dependent viscous properties, which cause the phenomena of creep and relaxation (see, e.g., Alava and Niskanen 2006). One of the simplest models for a viscoelastic solid is the Kelvin–Voigt model, which consists of a linear spring an…

research product

Asymptotical Convergence Evaluation for a Parabolic Problem Arising in Circuit Theory

research product

Asymptotic behaviour of mixed-type circuits. Delay time predicting

In the preceding chapter we have shown that the delay time problem in integrated circuits leads us to consider mixed-type circuits with distributed elements described by Telegraph Equations and lumped resistive and capacitive elements (Figure 4.5). Moreover, the well-posedness of the mathematical model (P(B, V0)) = (E) + (BC) + (IC) has been studied, various conditions for the existence, uniqueness and L2stability of different kind of solutions being formulated.

research product

Acoustic Detection of Moving Vehicles

This chapter outlines a robust algorithm to detect the arrival of a vehicle of arbitrary type when other noises are present. It is done via analysis of its acoustic signature against an existing database of recorded and processed acoustic signals. To achieve it with minimum number of false alarms, a construction of a training database of acoustic signatures of signals emitted by vehicles using the distribution of the energies among blocks of wavelet packet coefficients (waveband spectra, see Sect. 4.6) is combined with a procedure of random search for a near-optimal footprint (RSNOFP). The number of false alarms in the detection is minimized even under severe conditions such as: signals emi…

research product

Co-evolution between trust in teachers and higher education toward digitally-rich learning environments

Based on a powerful notion that the quality of higher education is crucial for innovation in digital economy and that such quality is subject to a conception of trust in teachers to deliver good education and advancement of information and communication technology (ICT), the dynamism of co-evolution between them was analyzed. Using a unique dataset representing the above system consisting of the rate of trust in teachers providing good education in the context of quality of education and their social status, of the level of higher education and the state of ICT advancement toward digitally-rich learning environments, an empirical numerical analysis of 20 countries was attempted. These count…

research product

A bibliometric approach to finding fields that co-evolved with information technology

Among the declining industries, for example music industry, some have been revived by information technology (IT). At the same time, in academic fields, some have expected co-evolutions between IT and other fields to cause the resurgence of either field. In this research, the clustering of citation networks with 14,438 academic papers resulted in the identification of 28 academic fields in the areas “Computer Science” or “Information Science and Library Science.” Co-evolutions between these 28 fields and citing fields to the 28 fields were evaluated by an investigation of contents; a methodology to search co-evolutions was also proposed. This paper proposes that pairs of academic fields (wi…

research product

Digitaalisista sairaaloista kognitiivisiin sairaaloihin

research product

Controllability-type properties for elliptic systems and applications

We consider approximate and exact controllability results for elliptic problems. These results enable one to formulate optimal shape design problems in a fixed domain with certain boundary conditions.

research product

Tutkijankoulutuksen ja tutkimustoiminnan tulosten tehokkaampi hyödyntäminen : yhteenveto käydystä tiede- ja koulutuspoliittisesta keskustelusta

research product

A SOLUTION TO THE DILEMMA BETWEEN R&D EXPANSION AND THE PRODUCTIVITY DECLINE: LESSONS FROM THE R&D MODELS IN AMAZON AND FINLAND

As a consequence of the two-faced nature of information and communication technology (ICT), a majority of ICT leaders have been confronting the critical problem of a dilemma between R&D expansion and productivity decline in the digital economy. However, Amazon has been able to accomplish a skyrocketing increase in R&D and market capitalization. Finland has also accomplished balanced advancement not only of welfare but also economic resurgence. This paper attempted to elucidate the miracle of two ICT leaders. By means of a comparative empirical analysis of respective development trajectories, the sources of their success were analyzed thereby the comparative advantage and disadvantag…

research product

Introduction: Signals and Transforms

In this chapter we outline some well known facts about periodic signals and transforms, which are needed throughout the book. For details we refer to the classical textbook Oppenheim and Schafer [2].

research product

Stability of Thermoelastic Layered Composite in Axial Movement

research product

Tekoälyn perusteita ja sovelluksia

research product

Mixed Circular Convolutions and Zak Transforms

In this chapter the notion of mixed circular convolution is introduced. The polynomial and discrete periodic splines defined on uniform grids are special cases of such convolutions. The so-called Zak transforms provide tools to handle mixed circular convolutions

research product

Cyber security training in Finnish basic and general upper secondary education

Cyber security in Finland is part of other areas of comprehensive security, as digital solutions multiply in society and technologies advance. Cyber security is one of the primary national security and nationaldefense concerns. Cyber security has quickly evolved from a technical discipline to a strategic concept. Cyber security capacity building can be measured based on the existence and number of research and developments, education and training programs, and certified professionals and public sector agencies.Cybersecurity awareness and the related civic skills play an increasingly important role as our societies become more digitalized. Improving citizens' cyber skills through education i…

research product

Palvelurobotiikka

research product

Omadata terveydenhuollon tietointensiivisessä rakenteessa

research product

Laskennallinen tiede - tieteen kolmas menetelmä : tilannekatsaus 2011

research product

Koulutuksen ja tutkimuksen merkitys maakuntien kehityksessä

research product

On O(h[sup4])-superconvergence of piecewise bilinear FE-approximations

research product

Some Optimization Problems

In this chapter, the problems of safety analysis and optimization of a moving elastic plate travelling between two rollers at a constant axial velocity are considered. We will use a model of a thin elastic plate subjected to bending and in-plane tension (distributed membrane forces). We will study transverse buckling (divergence) of the plate and its brittle and fatigue fracture caused by fatigue crack growth under cyclic in-plane tension (loading). Our aim is to find the safe ranges of velocities of an axially moving plate analytically under the constraints of longevity and stability. In the end of this chapter, the expressions for critical buckling velocity and the number of cycles before…

research product

A variational inequality approach to the problem of the design of the optimal covering of an obstacle

research product

Non-periodic Discrete Splines

Discrete Splines with different spans were introduced in Sect. 3.3.1. This chapter focuses on a special case of discrete splines whose spans are powers of 2. These splines are discussed in more detail. The Zak transform provides an integral representation of such splines. Discrete exponential splines are introduced. Generators of the discrete-spline spaces are described whose properties are similar to properties of polynomial-spline spaces generators. Interpolating discrete splines provide efficient tools for upsampling 1D and 2D signals. An algorithm for explicit computation of discrete splines is described.

research product

Maksetut henkilöverot alueittain ja ikäryhmittäin Suomessa 2000-2018

Tarkastelemme henkilöverotuksen kehitystä 2000-luvulla eri maakunnissa ja ikäryhmissä. Nuorimmat (alle 40-vuotiaiden) ikäluokat ovat jääneet vanhempien työikäisten ikäluokkien (yli 40-vuotiaiden) vero- ja siis myös tulokehityksestä jälkeen. Kokonaisuudessaan henkilöverokertymä on kasvanut noin 25 %, ja maakuntien väliset erot ovat vähentyneet merkittävästi vuosina 2000–2018. Nykyisen ajankohtaisen veroproblematiikan kannalta havaittu maakuntien myönteinen kehitys helpottaa maakuntapohjaisen sote-mallin rahoitusta. nonPeerReviewed

research product

Guaranteed Error Bounds for Conforming Approximations of a Maxwell Type Problem

This paper is concerned with computable error estimates for approximations to a boundary-value problem $$\mathrm{curl}\ {\mu }^{-1}\mathrm{curl}\ u + {\kappa }^{2}u = j\quad \textrm{ in }\Omega ,$$ where μ > 0 and κ are bounded functions. We derive a posteriori error estimates valid for any conforming approximations of the considered problems. For this purpose, we apply a new approach that is based on certain transformations of the basic integral identity. The consistency of the derived a posteriori error estimates is proved and the corresponding computational strategies are discussed.

research product

Biorthogonal Wavelet Transforms Originating from Discrete and Discrete-Time Splines

This chapter describes how to generate families of biorthogonal wavelet transforms in spaces of periodic signals using prediction p-filters originating from discrete-time and discrete splines. The transforms are generated by the lifting scheme (Sweldens (Wavelet applications in signal and image processing III, vol 2569, 1995, [7]), Sweldens (Appl Comput Harmon Anal 3:186–200, 1996, [8]), Sweldens (SIAM J Math Anal 29:511–546, 1997, [9]), see also Sect. 7.1 of this volume). The discrete-time wavelets related to those transforms are (anti)symmetric, well localized in time domain and have flat spectra. These families comprise wavelets with any number of local discrete vanishing moments (LDVMs)…

research product

FE-Modelling of Continuous Casting Problem

A mathematical model for simulating the heat transfer during solidification in continuous casting of steel is presented. The heat transfer coefficients along and across the strand are optimized. The evolution and location of thermal stresses are computed. Numerical examples are included.

research product

New Indicators of Approximation Errors for Problems in Continuum Mechanics

In this paper we present a new error indicator for approximate solutions of elliptic problems. We discuss error indication with the paradigm of the diffusion problem, however the techniques are easily adaptable to more complicated elliptic problems, for example to linear elasticity, viscous flow models and electromagnetic models. The proposed indicator does not contain mesh dependent constants and it admits parallelization. nonPeerReviewed

research product

Two-Sided Guaranteed Estimates of the Cost Functional for Optimal Control Problems with Elliptic State Equations

In the paper, we discuss error estimation methods for optimal control problems with distributed control functions entering the right-hand side of the corresponding elliptic state equations. Our analysis is based on a posteriori error estimates of the functional type, which were derived in the last decade for many boundary value problems. They provide guaranteed two-sided bounds of approximation errors for any conforming approximation. If they are applied to approximate solutions of state equations, then we obtain new variational formulations of optimal control problems and guaranteed bounds of the cost functional. Moreover, for problems with linear state equations this procedure leads to gu…

research product

Magnetic potential of transformer window

We describe how to calculate the magnetic potential in the window of an ideal transformer. The knowledge of this potential is a starting point for the determination of some other quantities of practical importance (such as leakage field, overheating of windings, circular currents, additional losses, short circuit forces in windings, etc.).

research product

Co-evolution between Trust in Teachers and Higher Education Enabled by ICT Advancement – A Suggestion to ICT Growing Economies

In light of the increasing significance of trust-based higher education towards digitally-rich learning environments, co-evolution dynamism between trust in teachers and higher education enabled by ICT advancement was analyzed. Using the rate of trust in teachers for good education in the Global Teacher Status Index, together with statistics on higher education level and ICT advancement, an empirical numerical analysis of 20 countries was attempted. It was identified that while ICT advanced countries have constructed a co-evolution between ICT, higher education and trust, ICT growing countries have not succeeded due to a vicious cycle between ICT and trust. Finland’s educational success can…

research product

Uncertainties in the heat conduction problems and reliable estimates

The heat conduction problems for anisotropic bodies are studied taking into account the uncertainties in the material orientation. The best estimations of the upper and lower bounds of the considered energy dissipation functional are based on the developing new approach consisting in solution of some optimization problems and finding the extremal internal material structures, which realize minimal and maximal dissipation.

research product

Biorthogonal Multiwavelets Originated from Hermite Splines

This chapter presents multiwavelet transforms that manipulate discrete-time signals. The transforms are implemented in two phases: 1. Pre (post)-processing, which transforms a scalar signal into a vector signal (and back). 2. Wavelet transforms of the vector signal. Both phases are performed in a lifting way. The cubic interpolating Hermite splines are used as a predicting aggregate in the vector wavelet transform. Pre(post)-processing algorithms which do not degrade the approximation accuracy of the vector wavelet transforms are presented. A scheme of vector wavelet transforms and three pre(post)-processing algorithms are described. As a result, we get fast biorthogonal algorithms to trans…

research product

Neo Open Innovation in the Digital Economy : Harnessing Soft Innovation Resources

Successive increases in R&D that creates new functionality are essential for global competitiveness. However, unexpectedly, as a consequence of the two-faced nature of information and communication technology (ICT), excessive R&D results in a marginal productivity decline leading to a decrease in digital value creation. In order to overcome such a dilemma, global ICT firms have been endeavoring to transform themselves into disruptive business model. Neo open innovation that harnesses soft innovation resources may be a solution to this critical question. On the basis of an empirical analysis focusing on forefront endeavors to this dilemma by global ICT firms, this paper attempted to demonstr…

research product

Digital solutions transform the forest-based bioeconomy into a digital platform industry : a suggestion for a disruptive business model in the digital economy

With the notion that the transformation of the forest-based bioeconomy in recent years provides insightful suggestions not only on the bioeconomy, but on business innovation, this paper conducts an empirical analysis of the transformation and attempts to extract suggestions for a digital-solution-driven, disruptive business model in the digital economy. Notwithstanding the potential broad cross-sectoral benefits, the natural environment, locality constraints, and incessant challenge of distance have impeded the balanced development of the bioeconomy. However, driven by digital solutions, the bioeconomy has taken big steps forward in recent years. Digitalization has enabled real-time, end-to…

research product

Co-evolution of three mega-trends nurtures un-captured GDP : Uber's ride-sharing revolution

Uber used a disruptive business model driven by digital technology to trigger a ride-sharing revolution. The institution- al sources of the company’s platform ecosystem architecture were analyzed to explain this revolutionary change. Both an empirical analysis of a co-existing development trajectory with taxis and institutional enablers that helped to create Uber’s platform ecosystem were analyzed. The analysis identified a correspondence with the “two-faced” nature of ICT that nurtures uncaptured GDP. This two-faced nature of ICT can be attributed to a virtuous cycle of decline in prices and an increase in the number of trips. We show that this cycle can be attributed to a self-propagating…

research product

On Computational Properties of a Posteriori Error Estimates Based upon the Method of Duality Error Majorants

In the present paper, we analyze computational properties of the functional type a posteriori error estimates that have been derived for elliptic type boundary-value problems by duality theory in calculus of variations. We are concerned with the ability of this type of a posteriori estimates to provide accurate upper bounds of global errors and properly indicate the distribution of local ones. These questions were analyzed on a series of boundary-value problems for linear elliptic operators of 2nd and 4th order. The theoretical results are confirmed by numerical tests in which the duality error majorant for the classical diffusion problem is compared with the standard error indicator used i…

research product

Biorthogonal Wavelet Transforms Originating from Splines

This chapter describes how to design families of biorthogonal wavelet transforms of signals and respective biorthogonal Wavelet bases in the signal space using spline-based prediction filters. Although the designed Wavelets originate from splines, they are not splines themselves. The design and implementation of the biorthogonal Wavelet transforms is done using the Lifting scheme. Most of the filters participating in the expansion of signals over the presented bases have infinite impulse responses and are implemented by recursive filtering whose computational cost is competitive with the FIR filtering cost. Properties of the designed Wavelets, such as symmetry, flat spectra, good time domai…

research product

Анализ и оптимизация устойчивости балок на сплошном упругом основании часть I (балки конечной длины) [Analysis and optimization of a beam on elastic foundation. Part I (Limited beams)]

Problems of defining the optimal (against buckling) cross section area distribution for beams interacting with elastic foundation are considered. The stability of limited pinned beams and infinite continuous beams is analyzed. For all beams under consideration, the stability analysis is performed as for constant as for variable distributions of strength beam characteristics. The critical length is determined and the variational statement of beam stability problems is presented for this beam type. The exact solution of optimal problem is presented in the case of linear dependence of limited beam bending hardness on beam cross section area. For the case of squared and cubic dependences, the n…

research product

Guaranteed Error Bounds I

In Chap. 3, we discussed the main ideas of fully reliable error control methods and the corresponding numerical algorithms with the paradigm of simple elliptic type problems. This chapter is intended to show a deep connection between a posteriori estimates of the functional type and physical relations generating the problem. Also, the goal of this chapter is to consider a wider set of problems arising in various applications and explain things in terms of computational mechanics. For this purpose, we begin with a simple class of mechanical problems (straight beams) and after that consider curvilinear beams and more complicated models of continuum mechanics (linear elasticity, viscous fluids…

research product

Application of Periodic Frames to Image Restoration

In this chapter, we present examples of image restoration using periodic frames. Images to be restored were degraded by blurring, aggravated by random noise and random loss of significant number of pixels. The images are transformed by periodic frames designed in Sects. 17.2 and 17.4, which are extended to the 2D setting in a standard tensor product way. In the presented experiments, performances of different tight and semi-tight frames are compared between each other in identical conditions.

research product

Value from Public Health Data with Cognitive Computing : loppuraportti

research product

Introduction: Periodic Filters and Filter Banks

In this chapter filtering of periodic signals is outlined. Periodic filters and periodic filter banks are defined. Perfect reconstruction filter banks are characterized via their polyphase matrices.

research product

On the Methods for Optimal Shape Design

A short survey of the numerical methods for solving optimal shape design problems is given.

research product

Spline-Based Wavelet Transforms

The Lifting Scheme introduced in (Sweldens, Appl. Comput. Harmon. Anal. 3(2), 186–200 (1996) and Sweldens, SIAM J. Math. Anal. 29(2), 511–546 (1997).) [3, 4] is a method that constructs bi-orthogonal wavelet transforms of signals and provides their efficient implementation. The main feature of the lifting scheme is that all the constructions are derived directly in the spatial domain and therefore can be custom designed to more general and irregular settings such as non-uniformly spaced data samples and bounded intervals. In this chapter, we outline the lifting scheme and describe how to use the local quasi-interpolating splines, introduced in Chap. 6, for the construction of wavelet transf…

research product

ICT-alan kehittäminen Keski-Suomessa : selvitys ICT-alan yrityksille Keski-Suomessa

research product

Hydro-Acoustic Target Detection

This chapter presents an example of utilization of the discrete–time wavelet packets, which are described in Sect. 9.1, to classification of acoustic signals and detection of a target. The methodology based on wavelet packets is applied to a problem of detection of a boat of a certain type when other background noises are present. The solution is obtained via analysis of boat’s hydro-acoustic signature against an existing database of recorded and processed hydro-acoustic signals. The signals are characterized by the distribution of their energies among blocks of wavelet packet coefficients.

research product

Multiwavelet Frames Originated From Hermite Splines

The chapter presents a method for the construction of multiwavelet frame transform for manipulation of discrete-time signals. The frames are generated by three-channel perfect reconstruction oversampled multifilter banks. The design of the multifilter bank starts from a pair of interpolating multifilters, which originate from the cubic Hermite splines. The remaining multifilters are designed by factoring polyphase matrices. Input to the oversampled analysis multifilter bank is a vector-signal, which is derived from an initial scalar signal by one out of three pre-processing algorithms. The post-processing algorithms convert the vector output from the synthesis multifilter banks into a scala…

research product

Tekoäly ja terveydenhuolto Suomessa

research product

Transformation of the Forest-based Bioeconomy by Embracing Digital Solutions

This paper attempts to explore a new insight to both industrialized and growing economies by demonstrating a digital-driven creative disruption in the forest-based bioeconomy which is beginning to replace its conventional and narrow concept of a forest-blinded economy. Notwithstanding the potential broad cross-sectoral benefits to both industrialized and growing economies, natural environments and locality constraints and the incessant challenge of distance have impeded balanced development of this economy. However, driven by digital solutions the economy has taken big steps forward in recent years. Digitalization has enabled real-time end-to-end supply chain visibility, improved delivery a…

research product

Yliopistojen tutkintokoulutuksen ja tutkimuksen rahoitus ja tulokset vuosina 2000-2004

research product

A parallel FE-splitting up method to parabolic problems

research product

Soft Innovation Resources: Enabler for reversal in GDP Growth in the Digital Economy

While Finland and Singapore have been maintaining world digital leaders position, they demonstrate interlaced contrast: high welfare with low GDP growth in Finland and higher GDP growth with lower welfare in Singapore. This provokes an uncaptured GDP postulate that Finnish wellbeing has developed more than one might conclude by GDP. However, a recent reversal in the GDP growth trend suggests the possibility that uncaptured GDP contributes to remove structural impediments in GDP growth.This paper demonstrates this hypothesis. An empirical analysis elucidating the inside the national accountings and institutional systems revealed that soft innovation resources have substituted for service cap…

research product

A Mobile Application Concept to Encourage Independent Mobility for Blind and Visually Impaired Students

This paper presents a user-centric application development process for mobile application to blind and visually impaired students. The development process connects the assistive technology experts, teachers and students from the school for visually impaired together to participate to the design of the mobile application. The data for the analysis is gathered from interviews and workshops with the target group. The main goal of the project is to examine how mobile application can be used to encourage and motivate visually impaired students to move independently indoors and outdoors. The application allows the students to interact with their environment through use of sensor technology now st…

research product

Blockchain : the ultimate disruption in the financial system

research product

Muutokset maksetuissa henkilöveroissa alueittain Suomessa 2000-luvulla

research product

Sensitivity analysis for discretized unilateral plane elasticity problem

Abstract Numerical realization of optimal shape design problems requires gradient information which is used in minimization procedures. There are several possibilities for obtaining this information. Here we present a method, based on the use of the material derivative approach, applied to the finite element discretization of the problem. The advantage of this approach is that is gives the exact values of gradient and it can be very easily implemented on computers. We apply this method in the case of contact problems, where the situation is more involved compared with the case of elasticity problems with classical boundary conditions. We concentrate on a special choice of the cost functiona…

research product

Unicorn-Open science for assessing environmental state, human health and regional economy

Open data and models are becoming increasingly available, but there are not yet good methods and platforms to turn those into systematic evidence-based decision support. Unicorn will produce such an environment based on existing theoretical and practical knowledge about decision support and models. This con sortium possesses the necessary models, data, and skills to set up an environment and demonstrate its func tionality and usefulness with several case studies related to the environmental issues, human health, and economy. The Unicorn environment will be built in a generic and systematic way so that it could even be come an international standard for evidence-based decision support. Devel…

research product

Two-Dimensional Orthogonal Wavelets and Wavelet Packets

This chapter extends the design of spline-based orthogonal discrete-time wavelets and wavelet packets to two-dimensional case. The corresponding transforms are implemented by using the 2D FFT.

research product

Tekoäly terveydenhuollossa : katsaus Aasiaan

research product

Suomen kansalliset SOTE-tiedonlähteet ja tietojen hyödyntäminen

research product

A posteriori error estimates for a Maxwell type problem

In this paper, we discuss a posteriori estimates for the Maxwell type boundary-value problem. The estimates are derived by transformations of integral identities that define the generalized solution and are valid for any conforming approximation of the exact solution. It is proved analytically and confirmed numerically that the estimates indeed provide a computable and guaranteed bound of approximation errors. Also, it is shown that the estimates imply robust error indicators that represent the distribution of local (inter-element) errors measured in terms of different norms. peerReviewed

research product

Nonlinear anisotropic heat conduction in a transformer magnetic core

In this chapter we deal with a quasilinear elliptic problem whose classical formulation reads: Find \( u \in {C^1}\left( {\bar \Omega } \right) \) such that u|Ω ∈ C 2(Ω) and $$ - div\left( {A\left( { \cdot ,u} \right)grad\;u} \right) = f\quad in\;\Omega $$ (9.1) $$ u = \bar u\quad on\;{\Gamma _1} $$ (9.2) $$ \alpha u + {n^T}A\left( { \cdot ,u} \right)grad\;u = g\quad on\;{\Gamma _2} $$ (9.3) where Ω ∈ L, n = (n 1, ..., n d ) T is the outward unit normal to ∂Ω, d ∈ {1, 2, ...,}, Γ1 and Γ2 are relatively open sets in the boundary ∂Ω, \({\overline \Gamma _1} \cup {\overline \Gamma _2} = \partial \Omega ,\,{\Gamma _1} \cap {\Gamma _2} = \phi\), \( A = \left( {{a_{ij}}} \right)_{i,j = 1}^d \) is…

research product

Numerical approximation of mixed models for digital integrated circuits

To analyse an electrical network many CAD (Computer Aided Design) circuit simulators are available today. The most well-known is probably SPICE -Nagel [1975]. Although this type of simulator is able to precisely compute the transient performances (as delay time), the usage of complete models of devices implies an extremely high time consumption. So, the circuit simulators are unappropriate for the initial stage of VLSI design where a high speed timing analyser (“timing simulator”) is required. To this goal, alternative approaches using either simpler device models or simpler numerical algorithms or easily computable formulae for delay time approximation, have been developed in the past deca…

research product

A new perspective of innovation toward a non-contact society - Amazon's initiative in pioneering growing seamless switching

This paper elucidates the inside of the black box of Amazon's unique research and development (R&D) dynamism that made it the world's top R&D leader by transforming “routine or periodic alterations” into “significant improvement” during the R&D process. This dynamism also succeeded in transforming the COVID-19 pandemic period into a springboard for new innovation, leading to Amazon's notable growth notwithstanding the pandemic. An empirical analysis using a techno-economic approach focusing on Amazon's endeavor to develop a series of advanced digital fashions (ADFs) and online-based luxury brands (neo-luxury) before and during the COVID-19 pandemic was conducted. Amazon became a global appa…

research product

Finite element approximation of vector fields given by curl and divergence

In this paper a finite element approximation scheme for the system curl is considered. The use of pointwise approximation of the boundary condition leads to a nonconforming method. The error estimate is proved and numerically tested.

research product

A modified least squares FE-method for ideal fluid flow problems

A modified least squares FE-method suitable e.g. for calculating the ideal fluid flow is presented. It turns out to be essentially more efficient than the conventional least squares method. peerReviewed

research product

Indicators of Errors for Approximate Solutions of Differential Equations

Error indicators play an important role in mesh-adaptive numerical algorithms, which currently dominate in mathematical and numerical modeling of various models in physics, chemistry, biology, economics, and other sciences. Their goal is to present a comparative measure of errors related to different parts of the computational domain, which could suggest a reasonable way of improving the finite dimensional space used to compute the approximate solution. An “ideal” error indicator must possess several properties: efficiency, computability, and universality. In other words, it must correctly reproduce the distribution of errors, be indeed computable, and be applicable to a wide set of approxi…

research product

Finite element approximations of the wave equation with Dirichlet boundary data defined on a bounded domain in R2

research product

Analysis and optimization against buckling of beams interacting with elastic foundation

We consider an infinite continuous elastic beam that interacts with linearly elastic foundation and is under compression. The problem of the beam buckling is formulated and analyzed. Then the optimization of beam against buckling is investigated. As a design variable (control function) we take the parameters of cross-section distribution of the beam from the set of periodic functions and transform the original problem of optimization of infinite beam to the corresponding problem defined at the finite interval. All investigations are on the whole founded on the analytical variational approaches and the optimal solutions are studied as a function of problems parameters. peerReviewed

research product

Mathematical modelling of physical phenomena

The word “physics” is derived from the Greek “fysis” which means nature. Physics investigates fundamental natural phenomena and thus physical knowledge has a very general character. This is also the reason why physics penetrates other areas including electrical engineering.

research product

CO-EVOLUTION BETWEEN CCC-DRIVEN CASH FLOW MANAGEMENT AND TRANSFORMATION OF R&D – AMAZON'S ENDEAVOR

Amazon became the world R&D leader in 2017 by rapidly increasing R&D investment. The company’s extremely large amount of R&D funds is the result of an ample free cash flow generated by sophisticated cash conversion cycle (CCC) management. Increased R&D induced business advancement and lean cost structure construction leading to further increase in cash flow which has stimulated interaction between vendors, customers, and Amazon via the Amazon marketplace. Activated interaction accelerated CCC advancement, a subsequent free cash flow increase, and user-driven innovation, thus accelerated the transformation of routine or periodic alteration activities into significant improvem…

research product

Engaging learners through virtual worlds

Abstract The aim of this paper is to explore how virtual worlds could support the engagement for learning. This paper reviews the results of studies that utilized virtual worlds to engage learners. The results are examined in two levels, namely learning gains and design principles. It has been found out that deeper learner engagement results in higher learning gains. In some studies better content retention is also noted. Many studies also suggest design principles for using virtual worlds for facilitating engaged learning. This paper builds a framework for the design and use of virtual worlds in education for better learner engagement.

research product

Digitalized bioeconomy: Planned obsolescence-driven circular economy enabled by Co-Evolutionary coupling

Driven by digital solutions, the bioeconomy is taking major steps forward in recent years toward achievement of the long-lasting goal of transition from a traditional fossil economy to a bioeconomy-based circular economy. The coupling of digitalization and bioeconomy is leading towards a digitalized bioeconomy that can satisfy the shift in consumers’ preferences for eco-consciousness, which in turn induces coupling of up-down stream operation in the value chain. Thus, the co-evolution of the coupling of digitalization and bioeconomy and of upstream and downstream operations is transforming the forest-based bioeconomy into a digital platform industry. Aiming at addressing this transformation…

research product

Bifurcation method of stability analysis and some applications

In this paper a new approach to the analysis of implicitly given function- als is developed in the frame of elastic stability theory. The approach gives an effective procedure to analyse stability behaviour, and to determine the bifur- cation points. Examples of application of the proposed approach for analysis of stability are presented, more precisely we consider the stability problem of an axially moving elastic panel, with no external applied tension, performing transverse vibrations. The analysis is applicable for many practical cases, for example, paper making and band saw blades.

research product

Errors Generated by Uncertain Data

In this chapter, we study effects caused by incompletely known data. In practice, the data are never known exactly, therefore the results generated by a mathematical model also have a limited accuracy. Then, the whole subject of error analysis should be treated in a different manner, and accuracy of numerical solutions should be considered within a framework of a more complicated scheme, which includes such notions as maximal and minimal distances to the solution set and its radius.

research product

Periodic Spline Wavelets and Wavelet Packets

This chapter presents wavelets and wavelet packets in the spaces of periodic splines of arbitrary order, which, in essence, are the multiple generators for these spaces. The SHA technique provides explicit representation of the wavelets and wavelet packets and fast implementation of the transforms in one and several dimensions.

research product

A Boundary Control Approach to an Optimal Shape Design Problem

Abstract We consider the problem of controlling the coincidence set in connection with an obstacle problem. We shall transform the obtained optimal shape design problem into a boundary control problem with Dirichlet boundary conditions.

research product

Image inpainting using directional wavelet packets originating from polynomial splines

The paper presents a new algorithm for the image inpainting problem. The algorithm is using a recently designed versatile library of quasi-analytic complex-valued wavelet packets (qWPs) which originate from polynomial splines of arbitrary orders. Tensor products of 1D qWPs provide a diversity of 2D qWPs oriented in multiple directions. For example, a set of the fourth-level qWPs comprises 62 different directions. The properties of the presented qWPs such as refined frequency resolution, directionality of waveforms with unlimited number of orientations, (anti-)symmetry of waveforms and windowed oscillating structure of waveforms with a variety of frequencies, make them efficient in image pro…

research product

Tekoäly ja rakennusten ennakoiva kunnossapito

Tämän raportin tarkoituksena on tarkastella tekoälyn hyödyntämistä rakennusten ennakoivassa kunnossapidossa. Raportissa esitellään KIRA-digi –hanke ja kuvataan Jyväskylän yliopiston KIRA-digi –pilottihanke. Raportin alussa on tekoälyn kehityspolku ja menetelmiä koskeva luku, jossa määritellään tekoälyn käsite ja tekoälyn menetelmiä, kuten neuroverkot, kone- ja syväoppiminen. Kolmas luku koskee älykkäitä rakennuksia ja kaupunkeja sekä esineiden internetiä (IoT), sensoreita, analytiikkaa, päälle puettavia laitteita ja teollista esineiden internetiä (IIoT). neljännessä raportin luvussa tarkastellaan rakennuksien ennakoivan kunnossapidon hyötyjä ja haittoja, kustannuksia ja säästöjä, prosessia …

research product

Postprocessing of a Finite Element Scheme with Linear Elements

In this contribution we first give a brief survey of postprocessing techniques for accelerating the convergence of finite element schemes for elliptic problems. We also generalize a local superconvergence technique recently analyzed by Křižek and Neittaanmaki ([20]) to a global technique. Finally, we show that it is possible to obtain O(h4) accuracy for the gradient in some cases when only linear elements are used. Numerical tests are presented.

research product

Guaranteed error bounds for a class of Picard-Lindelöf iteration methods

We present a new version of the Picard-Lindelof method for ordinary dif- ¨ ferential equations (ODEs) supplied with guaranteed and explicitly computable upper bounds of an approximation error. The upper bounds are based on the Ostrowski estimates and the Banach fixed point theorem for contractive operators. The estimates derived in the paper take into account interpolation and integration errors and, therefore, provide objective information on the accuracy of computed approximations. peerReviewed

research product

Jyväskylän yliopisto - ICT-alan innovatiivinen kehittäjä

research product

Älysopimusohjelmointi sosiaali- ja terveysalalla

research product

Tieto- ja viestintätekniikka Keski-Suomen peruskouluissa vuonna 2016

research product

On superconvergence techniques

A brief survey with a bibliography of superconvergence phenomena in finding a numerical solution of differential and integral equations is presented. A particular emphasis is laid on superconvergent schemes for elliptic problems in the plane employing the finite element method.

research product

Theoretical study on travelling web dynamics and instability under non-homogeneous tension

Problems of dynamics and stability of a moving web, travelling between two rollers at a constant velocity, are studied using analytical approaches. Transverse vibrations of the web are described by a partial differential equation that includes the centrifugal force, in-plane tension, elastic reaction and nonstationary inertial terms. The model of a thin elastic plate subjected to bending and non-homogeneous tension is used to describe the bending moment and the distribution of membrane forces. The stability of the plate is investigated with the help of studies of small out-of-plane vibrations. The influence of linearly distributed in-plane tension on the characteristics of the web vibration…

research product

Suomen terveysdata ja sen hyödyntäminen

research product

Non-Homogeneous Tension Profile

In this chapter, we will look at the influence of a skewed tension profile on the divergence instability of a travelling, thin elastic plate. The travelling plate is subjected to axial tension at the supports, but the tension distribution along the supports is not uniform. For the nonuniformity, we will use a linear distribution. First, we will perform a dynamic analysis of small time-harmonic vibrations, after which we will concentrate on the divergence instability problem. We will see that a small inhomogeneity in the applied tension may have a large effect on the divergence modes, and that inhomogeneity in the tension profile may significantly decrease the critical velocity of the plate.

research product

Discrete-Time Periodic Wavelet Packets

Direct and inverse wavelet and wavelet packet transforms of a spline are implemented by filtering the spline’s coordinates by two-channel critically sampled p-filter banks. In this chapter, those p-filter banks are utilized for processing discrete-time signals. The p-filter banks generate discrete-time wavelets and wavelet packets in the spaces of 1D and 2D periodic signals.

research product

Superconvergence phenomenon in the finite element method arising from averaging gradients

We study a superconvergence phenomenon which can be obtained when solving a 2nd order elliptic problem by the usual linear elements. The averaged gradient is a piecewise linear continuous vector field, the value of which at any nodal point is an average of gradients of linear elements on triangles incident with this nodal point. The convergence rate of the averaged gradient to an exact gradient in theL 2-norm can locally be higher even by one than that of the original piecewise constant discrete gradient.

research product

Learning platforms

research product

Fashion-driven Textiles as A Crystal of A New Stream for Stakeholder Capitalism – Amazon's Endeavor

Fashion reflects changes in socio-economic and cultural life which, in turn, changes fashion, and apparel boosts such change. Thus, in response to a shift in people’s preferences from economic functionality to supra-functionality beyond an economic value, the fashion industry has been gaining momentum worldwide. In the digital economy, the fashion industry is in the midst of global dynamic change stimulating volatility, velocity, variety and dynamism, which necessitate a digital solution. Digital business leader Amazon has succeeded in constructing an R&D-driven disruptive businesss model. This can be attributed to a virtuous cycle among user-driven innovation, advancement of the …

research product

Co-evolution between streaming and live music leads a way to the sustainable growth of music industry : Lessons from the US experiences

While digitization of music, particularly streaming services, has gained increasing popularity, it has also led to a steady decline in the revenues of recorded music industry. This is causing strong concern regarding a potential collapse of the music industry comparable to other print media industries such as newspaper and book publishing. However, recent changes in the music industry initiated by a resurgence of the live music industry are giving rise to some expectations for the survival and growth of the music industry. The parallel paths of increasing popularity of streaming services and a resurgence of live music suggest that these two dynamics are working together in a co-evolutionary…

research product

Nonlinear analysis of phase-locked loop

Abstract New method for the rigorous mathematical nonlinear analysis of PLL systems is suggested. This method allows to calculate the characteristics of phase detectors and carry out a rigorous mathematical analysis of transient process and stability of the system.

research product

Työttömyys IT-alalla koko Suomessa ja maakunnissa 2006-2015

research product

An analytical-numerical study of dynamic stability of an axially moving elastic web

This paper is devoted to a dynamic stability analysis of an axially moving elastic web, modelled as a panel (a plate undergoing cylindrical deformation). The results are directly applicable also to the travelling beam. In accordance with the dynamic approach of stability analysis, the problem of harmonic vi- brations is investigated via the study of the dependences of the system’s nat- ural frequencies on the problem parameters. Analytical implicit expressions for the solution curves, with respect to problem parameters, are derived for ranges of the parameter space where the natural frequencies are real-valued, corresponding to stable vibrations. Both axially tensioned and non-tensioned tra…

research product

Indirect Methods for Optimal Control Problems

This chapter is dedicated to the numerical approximation of Optimal Control Problems. The algorithms are based on the necessary conditions for optimality which allow us to use a descent method for the minimization of the cost functional.

research product

Tekoäly terveydenhuollossa

research product

An optimization approach for communal home meal delivery service

Abstract: This paper is the first to discuss the communal home meal delivery problem. The problem can be modelled as a multiple travelling salesman problem with time windows, that is closely related to the well-studied vehicle routing problem with time windows. Experimental results are reported for a real-life case study from Central Finland over several alternative scenarios using the SPIDER commercial solver. The comparison with current practice reveals that a significant savings potential can be obtained using off-the-shelf optimization tools. As such, the potential for supporting real-life communal routing problems can be considered to be important for VRP practitioners.

research product

Methods for optimal shape design of electrical devices

Often the primary problem facing designers of structural systems is determining the shape of the structure. In spite of graphical work stations and modern software for analyzing the structure, finding the best geometry for the structure by “trial and error” is still a very tedious and timeconsuming task. The goal in optimal shape design (structural optimization, or redesign) is to computerize the design process and therefore shorten the time it takes to design new products or improve the existing design. Structural optimization is already used in many applications in industry. In general, however, structural optimization is just beginning to penetrate the industrial community. Integrating F…

research product

Interventiot ja tekoäly terveydenhuollossa

research product

Transportation technologies

research product

Experiences and motivations of the young for participation in virtual worlds

Abstract The aim of this paper is to analyze the motivations and experiences of children to utilize virtual worlds. The paper identifies the activities that children perform in virtual worlds, features they use as well as the reasons for abandoning these virtual worlds. The paper presents results of a qualitative field study. The results indicate that features that are liked in the virtual worlds are similar to games. The main reasons to abandon virtual worlds were increased needs for social networking and better gaming experiences. Students showed interest in using games and virtual worlds at schools, but were generally rather skeptic about this possibility.

research product

A Control Problem for a Class of Epidemics

We consider a mathematical model corresponding to a class of epidemics. Controlling an epidemic is usually difficult. To implement the control policy suggested by a mathematical analysis in the real world is never easy. However, suggestions can be given to the public authorities about the effects of a particular control policy, and in this sense analysis and simulation by mathematical models becomes a powerful tool.

research product

Optimal shape design and unilateral boundary value problems: Part II

In the first part we give a general existence theorem and a regularization method for an optimal control problem where the control is a domain in R″ and where the system is governed by a state relation which includes differential equations as well as inequalities. In the second part applications for optimal shape design problems governed by the Dirichlet-Signorini boundary value problem are presented. Several numerical examples are included.

research product

Mixed Convolutions and Zak Transforms

In this chapter we introduce the mixed continuous–discrete and discrete–discrete convolutions. Important special cases of such convolutions are the polynomial and discrete splines, respectively. The Zak transforms, which are introduced in the chapter, provide integral representation of signals, which, in the following chapters, serves as a tool for the design of splines and spline-wavelets and operations over them. The exponential splines, which are the Zak transforms of polynomial and discrete B-splines are introduced. Explicit formulas for the characteristic functions of splines’ spaces are derived.

research product

Optimal Control for Plate Problems

The variational approach leading to indirect methods Optimal Control Problems is applied to the study of simply supported and clamped plates. A unified approach based on distributed optimal control problems governed by second order elliptic boundary value problems and their penalization is used.

research product

Fast Computation by Subdivision of Multidimensional Splines and Their Applications

We present theory and algorithms for fast explicit computations of uni- and multi-dimensional periodic splines of arbitrary order at triadic rational points and of splines of even order at diadic rational points. The algorithms use the forward and the inverse Fast Fourier transform (FFT). The implementation is as fast as FFT computation. The algorithms are based on binary and ternary subdivision of splines. Interpolating and smoothing splines are used for a sample rate convertor such as resolution upsampling of discrete-time signals and digital images and restoration of decimated images that were contaminated by noise. The performance of the rate conversion based spline is compared with the…

research product

On a global superconvergence of the gradient of linear triangular elements

Abstract We study a simple superconvergent scheme which recovers the gradient when solving a second-order elliptic problem in the plane by the usual linear elements. The recovered gradient globally approximates the true gradient even by one order of accuracy higher in the L 2 -norm than the piecewise constant gradient of the Ritz—Galerkin solution. A superconvergent approximation to the boundary flux is presented as well.

research product

Periodic Orthogonal Wavelets and Wavelet Packets

In this chapter, we discuss how to derive versatile families of periodic discrete-time orthogonal wavelets and wavelet packets from discrete and discrete-time splines outlined in Chap. 3. These wavelets and wavelet packets, although not having compact supports, are well localized in the time domain. They can have any number of discrete vanishing moments. Their DFT spectra tend to have a rectangular shape when the spline order grows and provide a collection of refined splits of the Nyquist frequency band. The wavelet and wavelet packet transforms are implemented in a fast way using the FFT.

research product

Calculation of Splines Values by Subdivision

Assume, the samples of a spline \(S(t)\in {}^{p}\fancyscript{S}\) on the grid \(\mathbf{g} =\{k\}_{k\in \mathbb {Z}}\) are available: \(S(k)=y[k]\). Subdivision schemes are proposed to calculate the spline’s values at dyadic and triadic rational points \(S(k/2^m)\) and \(S(k/3^m)\). The SHA technique provides fast and explicit implementation of the subdivision for one- and two-dimensional periodic splines.

research product

Internet of Things for Sustainable Smart Education: An Overview

In the realm of fourth-generation industrialization, there will be great demand for a skilled workforceTo produce a skilled workforce, we need sustainable education with quality and equity. Conventional ways of delivering and managing education would not fulfil the demands of the fourth industrial revolution (4IR). Disruptive technologies, such as Internet of Things (IoT), have great potential in revolutionizing the current educational setup. Therefore, this research work aims to present an overview of the capabilities of IoT applications in educational settings. Our research article digs into recent research carried out referring to IoT applications in education and provides a detailed ins…

research product

Fashion-driven Textiles as A Crystal of A New Stream for Stakeholder Capitalism : Amazon’s Endeavor

Fashion reflects changes in socio-economic and cultural life which, in turn, changes fashion, and apparel boosts such change. Thus, in response to a shift in people’s preferences from economic functionality to supra-functionality beyond an economic value, the fashion industry has been gaining momentum worldwide. In the digital economy, the fashion industry is in the midst of global dynamic change stimulating volatility, velocity, variety and dynamism, which necessitate a digital solution. Digital business leader Amazon has succeeded in constructing an R&D-driven disruptive businesss model. This can be attributed to a virtuous cycle among user-driven innovation, advancement of the Internet, …

research product

Memetic Variation Local Search vs. Life-Time Learning in Electrical Impedance Tomography

In this article, various metaheuristics for a numerical optimization problem with application to Electric Impedance Tomography are tested and compared. The experimental setup is composed of a real valued Genetic Algorithm, the Differential Evolution, a self adaptive Differential Evolution recently proposed in literature, and two novel Memetic Algorithms designed for the problem under study. The two proposed algorithms employ different algorithmic philosophies in the field of Memetic Computing. The first algorithm integrates a local search into the operations of the offspring generation, while the second algorithm applies a local search to individuals already generated in the spirit of life-…

research product

Co-Evolutionary Coupling via a Digital-bio Ecosystem : A Suggestion for a New R&D Model in the Digital Economy

A solution to the critical problem of a dilemma between R&D expansion and productivity decline that a majority of information and communication technology (ICT) leaders have been confronting in the digital economy is expected. It can be expected by a spinoff from economic functionality-seeking GDP-based coevolution cycle to supra-functionality beyond an economic value-seeking uncaptured GDP-driven coevolution cycle. However, the transformation dynamism remains a black box. By means of numerical simulations based on empirical analyses of the development trajectories of global ICT leaders, focusing on Amazon and Finland, together with an intensive review of preceding analyses, this paper atte…

research product

Tekoälyn hyödyntäminen lääkehuollossa

research product

Kansalaisten kulutuskäyttäytymisen muutokset digitalisoituvassa yhteiskunnassa

research product

Comparative Study of the a Posteriori Error Estimators for the Stokes Problem

The research presented is focused on a comparative study of a posteriori error estimation methods to various approximations of the Stokes problem. Mainly, we are interested in the performance of functional type a posterior error estimates and their comparison with other methods. We show that functional type a posteriori error estimators are applicable to various types of approximations (including non-Galerkin ones) and robust with respect to the mesh structure, type of the finite element and computational procedure used. This allows the construction of effective mesh adaptation procedures in all cases considered. Numerical tests justify the approach suggested.

research product

Fracture and Fatigue of Travelling Plates

In this chapter, problems of fracture and stability of a moving plate, travelling in a system of rollers at a constant velocity, are studied. It is known that in the manufacturing process, there may occur many kinds of defects in the paper web, such as edge cracks and blister and fiber cuts. Our aim is to tackle this problem and analyse theoretically how the defects change the behaviour. We will use the model of a thin elastic plate made of brittle material. A plate with initial cracks is studied, subjected to constant tension and cyclic tension. As a result, we will show how to find safe parameter ranges of transport velocities and in-plane tensions when fracture, stability and constraints…

research product

Non-periodic Discrete-Spline Wavelets

This chapter describes wavelet analysis in the spaces of discrete splines whose spans are powers of 2. This wavelet analysis is similar to wavelet analysis in the polynomial-spline spaces. The transforms are based on relations between exponential discrete splines from different resolution scales. Generators of discrete-spline wavelet spaces are described. The discrete-spline wavelet transforms generate wavelet transforms in signal space. Practically, wavelet transforms of signals are implemented by multirate filtering of signals by two-channel filter banks with the downsampling factor 2 (critically sampled filter banks). The filtering implementation is accelerated by switching to the polyph…

research product

Stationary semiconductor equations

The behaviour of a semiconductor device is usually modelled by three coupled nonlinear partial differential equations of elliptic type. Such a system for the transport of mobile charge carriers was first introduced by Van Roosbroeck [Van Roosbroeck] in 1950. Nowadays there are many models which differ in their choice of unknowns, scales, various types of nonlinearities etc. (see, e.g., [Brezzi], [Groger], [Markowich], [Markowich, Ringhofer, Schmeiser], [Mock, 1972], [Polak, den Heijer, Schilders, Markowich], [Pospisek], [Pospisek, Segeth, Silhan], [Selberherr], [Sze], [Zlamal, 1986]).

research product

A new paradox of the digital economy - Structural sources of the limitation of GDP statistics

The Internet has dramatically changed the way we conduct business and our daily lives by provided us with unprecedented services and conveniences. However, contrary to such accomplishments, productivity in industrialized countries is now experiences an apparent decline. This has raised the question of a possible productivity paradox in the digital economy. The limitation of GDP statistics in measuring the advancement of the digital economy has thus become an important subject. This paper analyzed the structural sources of this problem. Utilizing the results of empirical analyses of national, industrial, and individual behavior in the digital economy, solutions to these critical issues were …

research product

Harnessing soft innovation resources leads to neo open innovation

Advancement of the digital economy has transformed the concept of the growth crossover in nations and firms, both concerning input and output. Advanced economies have been confronting a dilemma between input increases and output decreases. Contrary to traditional expectations, excessive increase in input has resulted in a productivity decline in output. A solution to this dilemma can only be expected by harnessing the vigor of soft innovation resources that lead to neo open innovation in the digital economy. This paper attempts to demonstrate this hypothetical view. Based on an empirical analysis of the development trajectories of 140 countries and 500 global ICT firms, dynamism, resulting …

research product

On some bifurcation analysis techniques for continuous systems

This paper is devoted to techniques in bifurcation analysis for continuous mechanical systems, concentrating on polynomial equations and implicitly given functions. These are often encountered in problems of mechanics and especially in stability analysis. Taking a classical approach, we summarize the relevant features of the cubic polynomial equation, and present some new aspects for asymptotics and parametric representation of the solutions. This is followed by a brief look into the implicit function theorem as a tool for analyzing bifurcations. As an example from mechanics, we consider bifurcations in the transverse free vibration problem of an axially compressed beam. peerReviewed

research product

A Model for Carbon Macrosegregation

In this paper we present models for calculating temperature distribution and macrosegregations for solidification problem in continuous casting of steel. Numerical examples illustrate the importance of liquid flow as a cause for segregations.

research product

Non-periodic Polynomial Splines

In this chapter, we outline the essentials of the splines theory. By themselves, they are of interest for signal processing research. We use the Zak transform to derive an integral representation of polynomial splines on uniform grids. The integral representation facilitated design of different generators of spline spaces and their duals. It provides explicit expressions for interpolating and smoothing splines of any order. In forthcoming chapters, the integral representation of splines will be used for the constructions of efficient subdivision schemes and so also for the design spline-based wavelets and wavelet frames.

research product

Quasi-interpolating and Smoothing Local Splines

In this chapter, local quasi-interpolating and smoothing splines are described. Although approximation properties of local spline are similar to properties of the global interpolating and smoothing splines, their design does not require the IIR filtering of the whole data array. The computation of a local spline value at some point utilizes only a few adjacent grid samples. Therefore, local splines can be used for real-time processing of signals and for the design of FIR filter banks generating wavelets and wavelet frames (Chaps. 12 and 14). In the chapter, local splines of different orders are designed and their approximation properties are established which are compared with the propertie…

research product

Mechanics of Moving Materials

research product

Big datan tutkimus ja opetus Jyväskylän yliopistossa

research product

Waveguides. Radiation Principle. Scattering Matrices

Chapter 2 exposes a mathematical model of a waveguide with several cylindrical ends going to infinity, basic notions and mathematical results (with complete proofs) needed in successive chapters: waves, continuous spectrum eigenfunctions, intrinsic radiation principle, and scattering matrices.

research product

Drops moving in flow with chernical reaction

We propose a free boundary model described by coupled Navier-Stokes and chemical reaction equations with discontinuous coefRcients to simulate the chemical re- ¿ctions in viscous drops moving in a viscous incompressible ûuid. Approximation of the solution by a special ñnite element method (FEM) with a method of mapping is discussed. Several numerical resulùs åre presented.

research product

Scalable Deployment of Efficient Transportation Optimization for SMEs and Public Sector

Transportation planning is central activity in logistic network design. In this study, we examine the deployment of optimization methodology to transportation planning. More specifically, we examine the adoption of system solving the well-known combinatorial optimization problem, the vehicle routing problem (VRP). Its application has resulted in efficiency gains in transportation logistics, but they have not been very widespread, and especially small-scale operators have not yet benefited from these systems. In this paper, we present a prospective case study on the issues during deployment of optimization, especially in the context of small and medium enterprises (SMEs). We propose a novel …

research product

On the Control of the Secondary Cooling in the Continuous Casting Process

Continuous casting is today replacing ingot casting as the major process for the production of steel in the form of slabs, blooms, billets etc. The complexity of this process is such that until recently innovations to machine design could only be tested by full scale runs on the production machine. This is extremely costly and in many cases production cannot be delayed for such tests to occur. For offering alternative means of testing new designs, numerical simulation models of the continuous casting process have been developed, especially during the last decade. We refer to conference proceedings [3], [5], [6] [16]. Furthermore we mention articles [4], [9], [13], [23], [24] concerning heat…

research product

Detection of Incipient Bearing Fault in a Slowly Rotating Machine Using Spline Wavelet Packets

This chapter describes a successful application of spline-based wavelet packet transforms (WPTs) described in Chap. 4 to a complicated problem of detection of incipient defects in rolling element bearings by the analysis of recorded vibration signals. The methodology presented in this chapter is applied to the analysis of vibration data recorded from large bearings working in real unfavorable operation conditions in presence of strong noise and vibrations from multiple internal and external sources. It relies on properties of discrete spline-based wavelet packets such as orthogonality, near-rectangular spectra, transient oscillating shapes of testing waveforms and fast implementation of tra…

research product

Errata to “On the instability of an axially moving elastic plate” [Int. J. Solids Struct. 47 (2010) 91–99]

research product

Computation of the lock-in ranges of phase-locked loops with PI filter

In the present work the lock-in range of PLL-based circuits with proportionallyintegrating filter and sinusoidal phase-detector characteristics are studied. Considered circuits have sinusoidal phase detector characteristics. Analytical approach based on the methods of phase plane analysis is applied to estimate the lock-in ranges of the circuits under consideration. Obtained analytical results are compared with simulation results. peerReviewed

research product

Post‐processing of Gauss–Seidel iterations

research product

A variational inequality approach to constrained control problems for parabolic equations

A distributed optimal control problem for parabolic systems with constraints in state is considered. The problem is transformed to control problem without constraints but for systems governed by parabolic variational inequalities. The new formulation presented enables the efficient use of a standard gradient method for numerically solving the problem in question. Comparison with a standard penalty method as well as numerical examples are given.

research product

Institutional systems inducing R&D in Amazon- the role of an investor surplus toward stakeholder capitalization

Abstract Amazon demonstrated a conspicuous increase in R&D and became the world's top R&D firm in 2017 with a skyrocketing increase in market capitalization, making it close to being the world's biggest company. Such a remarkable accomplishment can be attributed to Amazon's institutional systems, which orchestrate techno-financing systems that fuse a unique R&D transformation system and a sophisticated financing system centered on the cash conversion cycle (CCC). These institutional systems support and endorse aggressive investment in R&D that incorporates the characteristics of uncertainty, a long lead time, and successive inflows of very large amounts of funding without interruption. Whil…

research product

On the convergence of the finite element approximation of eigenfrequencies and eigenvectors to Maxwell's boundary value problem

research product

A New Concept of R&D in NEO Open Innovation : Transformation of R&D Triggered By Amazon

Amazon was the world’s top R&D firm in 2017. Its R&D investment was double that of 2015, quintuple that of 2012, and tenfold that of 2011. It deploys a unique R&D model as conducting “routine or periodic alternations” and “significant improvement” simultaneously. Since traditionally the former is classified as non-R&D, Amazon’s rapid and notable increase has raised the question of a new R&D definition in the digital economy. By means of an empirical analysis of the Amazon’s R&D model, this paper attempted to provide a convincing answer to this question. Amazon has invested considerable resources in extremely innovative business areas, which has developed its assimilation capacity. In parall…

research product

Calculation of nonlinear stationary magnetic field

Currently, linear models of various physical fields can successfully be implemented numerically. Efficient numerical methods have been developed during last two or three decades and sufficiently capable computers are available. The situation is different with nonlinear models. There is no general numerical method for solving all nonlinear problems, and consequently every class of problems has to be investigated individually. The specific features of the class are taken into account in this process [Berger].

research product

Spline Algorithms for Deconvolution and Inversion of Heat Equation

In this chapter, we present algorithms based on Tikhonov regularization for solving two related problems: deconvolution and inversion of heat equation. The algorithms, which utilize the SHA technique, provide explicit solutions to the problems in one and two dimensions.

research product

Snapshot Spectral Imaging

This chapter describes an application of the spline-based wavelet frames to the spectral imaging. It presents a method that enables to convert a regular digital camera into a snapshot spectral imager by equipping the camera with a dispersive diffuser and with a compressed sensing-based algorithm for digital processing. The method relies on the assumption that typical images can be sparsely represented in the frame domain. The solution is found from the constrained \(l_{1}\) minimization of a functional by Bregman iterations. Results of optical experiments are reported. The chapter is based on the paper (Golub et al., Appl. Opt. 55, 432–443, (2016), [11]).

research product

Co-Evolutionary Coupling Between Captured and Uncaptured GDP Cycles : Cross Learning from Amazon and Finland Models for Sustainability

A solution to the critical problem of a dilemma between R&D expansion and productivity decline that a majority of information and communication technology (ICT) leaders have been confronting in the digital economy is expected. It can be expected by a spinoff from economic functionality-seeking GDP-based coevolution cycle to supra-functionality beyond an economic value-seeking uncaptured GDP-driven coevolution cycle. However, the transformation dynamism remains a black box. By means of numerical simulations based on empirical analyses of the development trajectories of global ICT leaders, focusing on Amazon and Finland, together with an intensive review of preceding analyses, this paper atte…

research product

Platform economy & digital platforms

research product

Digital healthcare platform

research product

Regularization and finite element approximation of the wave equation with Dirichlet boundary data

research product

Minustako maisteri? : maisteriklinikka tietotekniikan opiskelijoiden ohjauksen tehostamisessa

research product

Industrial and service robots

research product

Optimization of the domain in elliptic variational inequalities

research product

Tekoälyä hyödyntävät ratkaisut ja mahdollisuudet mielenterveyden häiriöissä

research product

Resonant Tunneling in 2D-Waveguides with Several Resonators

In this chapter, we consider a two-dimensional waveguide that coincides with a strip having \(n+1\) narrows of small diameter \(\varepsilon \). All narrows are of the same shape and are spaced from each other by equal distances. Parts of the waveguide between two neighboring narrows play the role of resonators. The wave function of a free electron satisfies the Dirichlet boundary value problem for the Helmholtz equation in the waveguide. Near a simple eigenvalue of the closed resonator there are n resonant peaks of height close to 1. We let \(\varepsilon \rightarrow 0\) and obtain asymptotic formulas for the resonant energies and for the widths of the resonant peaks at their half-height. Th…

research product

On the finite element approximation for maxwell’s problem in polynomial domains of the plane

The time-harmonic Maxwell boundary value problem in polygonal domains of R2 is considered. The behaviour of the solution in the neighbourhood of nonregular boundary points is given and asymptotic error estimates in L2- and in curl-div-norm for a finite element approximation of the solution are derived

research product

Prospectives to tractor cabin design with computational acoustics tools

Computational acoustical models allow automated optimization of tractor design with respect to acoustic properties, which could speed up significantly the design process of tractor cabin prototypes. This article gives insightful prospectives to the tractor design process by considering modern computational acoustics technology. Mathematical formulation for a system consisting of vibrating elastic tractor structure and airfilled acoustic enclosure are given and a related numerical solution technique with finite element method (FEM) is presented. Simulation results produced with commercially available software are reviewed. nonPeerReviewed

research product

Data Compression Using Wavelet and Local Cosine Transforms

The chapter describes an algorithm that compresses two-dimensional data arrays, which are piece-wise smooth in one direction and have oscillating events in the other direction. Seismic, hyper-spectral and fingerprints data, for example, have such a mixed structure. The transform part of the compression process is an algorithm that combines wavelet and local cosine transform (LCT). The quantization and the entropy coding parts of the compression are taken from the SPIHT codec. To efficiently apply the SPIHT codec to a mixed coefficients array, reordering of the LCT coefficients takes place. On the data arrays, which have the mixed structure, this algorithm outperforms other algorithms that a…

research product

Method for Computing Scattering Matrices

Chapter 4 presents statement and justification of a method for approximate computing a waveguide scattering matrix. As an approximation to a row of such a matrix, a minimizer of a quadratic functional is suggested. To construct the functional, one has to solve a boundary value problem in a bounded domain obtained by cutting off the cylindrical ends of the waveguide at distance R. The minimizer tends to the scattering matrix row at exponential rate as R increases to infinity.

research product

Polynomial Spline-Wavelets

This chapter presents wavelets in the spaces of polynomial splines. The wavelets’ design is based on the Zak transform, which provides an integral representation of spline-wavelets. The exponential wavelets which participate in the integral representation are counterparts of the exponential splines that were introduced in Chap. 4. Fast algorithms for the wavelet transforms of splines are presented. Generators of spline-wavelet spaces are described, such as the B-wavelets and their duals and the Battle-Lemarie wavelets whose shifts form orthonormal bases of the spline-wavelet spaces.

research product

finite element methods

Two robot patch recovery methods with built-in field equations and boundary conditions superconvergence similarities in standard and mixed finite element methods on the FEM for the Navier-Stokes equations in the domains with corner singularities projections in finite element analysis and application element analysis method and superconvergence quadratic interpolation polynomials in vertices of strongly regular triangulations explicit error bounds for a nonconforming finite element method analysis of the average efficiency of an error estimator on the mesh for difference schemes of higher accuracy for the heat-conduction equation shape design sensitivity formulae approximated by means of a r…

research product

Анализ и оптимизация устойчивости балок на сплошном упругом основании часть II (бесконечные балки) [Analysis and optimization of a beam on elastic foundation. Part II (Infinite beams)]

Problems of defining of optimal (against buckling) cross section area distribution for beams interacting with elastic foundation are considered. The stability of limited pinned beams and infinite continuous beams is analyzed. For all beams under consideration, the stability analysis is performed as for constant as for variable distributions of strength beam characteristics. The critical length is determined and the variational statement of beam stability problems is presented for this beam type. For infinite continuous beams, the stability problems are investigated as for constant as for periodic distribution of strength characteristics. In the second case, the analysis of infinite beam can…

research product

Introduction: Digital Filters and Filter Banks

A basic operation of spectr is filterin. In this introductory chapter, processing of one- and two-dimensional signals by digital filters and filter banks is outlined. A polyphase implementation of multirate filtering is described. The application of filtering with IIR filters, whose transfer functions are rational, is described. Bases and frames in the signals’ space that are generated by perfect reconstruction filter banks are discussed. The Butterworth filters, which are used in further constructions, are introduced.

research product

Approximation of the Maxwell equations in anisotropic inhomogeneous media

Let Ω ∈ L be in ℝ 2. We consider the initial-boundary value problem $$ \begin{array}{l}rot\,E\left( {x,t} \right) + \mu \left( x \right)\frac{\partial }{{\partial t}}H\left( {x,t} \right) = J\left( {x,t} \right), \\\left( {x,t} \right) \in \Omega \, \times \,(0,T], \\curl\,H\left( {x,t} \right) - \varepsilon \left( {\frac{\partial }{{\partial t}}} \right)E\left( {x,t} \right) = k\left( {x,t} \right), \\n \wedge E\left( {x,t} \right) = 0, \\\left( {x,t} \right) \in \partial \Omega \, \times \,(0,T], \\\left( {E\left( {x,0} \right),H\left( {x,0} \right)} \right) = \left( {{E_0}\left( x \right),\,{H_0}\left( x \right)} \right), \\x \in \bar \Omega \\\end{array} $$ (13.1) .

research product

Huippunopea kiinteä laajakaistaverkko : informaatioteknologian strateginen infrastruktuuri-investointi

research product

IT-alan merkitys yhteiskunnassa ja tutkimus-ja innovaatiotoiminnan kehittäminen

research product

Wavelet Frames Generated by Perfect Reconstruction Filter Banks

It was indicated in Sect. 2.2 that oversampled perfect reconstruction (PR) filter banks generate specific types of frames in the signal space. In this chapter, a family of tight and semi-tight frames is presented. The three- and four-channel filter banks that generate the framed originate from polynomial and discrete splines. Those frames have properties, which are attractive for signal processing, such as symmetry, interpolation, flat spectra. These properties are combined with fine time-domain localization and efficient implementation. This family includes framelets, that have any number of discrete vanishing moments. Non-compactness of their supports is compensated by exponential decay o…

research product

Cyber security of vehicle CAN bus

There are currently many research projects underway concerning the intelligent transport system (ITS), with the intent to develop a variety of communication solutions between vehicles, roadside stations and services. In the near future, the roll-out of 5G networks will improve short-range vehicle-to-vehicle traffic and vehicle-to-infrastructure communications. More extensive services can be introduced due to almost non-delayed response time. Cyber security is central for the usability of the services and, most importantly, for car safety. The Controller Area Network (CAN) is an automation bus that was originally designed for real-time data transfer of distributed control systems to cars. La…

research product

Local Splines on Non-uniform Grid

In this Chapter and in the next Chap. 7, we deal with continuous rather than discrete and discrete-time splines. In these and only these chapters, we abandon the assumption that the grid, on which the splines are constructed, is uniform and consider splines on arbitrary grids. Two types of local cubic and quadratic splines on non-uniform grids are described: 1. The simplest variation-diminishing splines and 2. The quasi-interpolating splines. The splines are computed by simple fast computational algorithms that utilize relations between the splines and interpolation polynomials. In addition, these relations provide sharp estimations of splines’ approximation accuracy. These splines can serv…

research product

Existence for shape optimization problems in arbitrary dimension

We discuss some existence results for optimal design problems governed by second order elliptic equations with the homogeneous Neumann boundary conditions or with the interior transmission conditions. We show that our continuity hypotheses for the unknown boundaries yield the compactness of the associated characteristic functions, which, in turn, guarantees convergence of any minimizing sequences for the first problem. In the second case, weaker assumptions of measurability type are shown to be sufficient for the existence of the optimal material distribution. We impose no restriction on the dimension of the underlying Euclidean space.

research product

Introduction: Periodic Signals and Filters

In this chapter we briefly outline some well-known facts about Discrete-time periodic signals, their transforms and periodic digital filters and filter banks. For details we refer to the classical textbook A. V. Oppenheim and R. W. Schafer (Discrete-Time Signal Processing, Prentice Hall, New York, 2010, [3]) and Volume I of our book (Averbuch, Neittaanmaki and Zheludev, Spline and Spline Wavelet Methods with Applications to Signal and Image Processing, Periodic Splines, vol. 1 (Springer, Berlin, 2014)) [1] Throughout the volume, unless other indicated, \(N=2^{j}, \;j\in \mathbb {N}\).

research product

Drilling Systems: Stability and Hidden Oscillations

There are many mathematical models of drilling systems Despite, huge efforts in constructing models that would allow for precise analysis, drilling systems, still experience breakdowns. Due to complexity of systems, engineers mostly use numerical analysis, which may lead to unreliable results. Nowadays, advances in computer engineering allow for simulations of complex dynamical systems in order to obtain information on the behavior of their trajectories. However, this simple approach based on construction of trajectories using numerical integration of differential equations describing dynamical systems turned out to be quite limited for investigation of stability and oscillations of these s…

research product

Parallel Genetic Solution for Multiobjective MDO

Publisher Summary This chapter reviews a multiobjective, multidisciplinary design optimization of two-dimensional airfoil designs. The control points on leading and trailing edges remain fixed, and the y-coordinates of the other control points are allowed to change during the optimization process. The grid for the Euler solver depends continuously and smoothly on the design parameters. The number of nodes and elements in the mesh might vary according to design because the meshes for the Helmholtz solver are done using the local fitting. The computations are made on an IBM SP2 parallel computer using high-performance switch and the MPICH message-passing library. As gradients are not required…

research product

On the instability of an axially moving elastic plate

Problems of stability of an axially moving elastic band travelling at constant velocity between two supports and experiencing small transverse vibrations are considered in a 2D formulation. The model of a thin elastic plate subjected to bending and tension is used to describe the bending moment and the distribution of membrane forces. The stability of the plate is investigated with the help of an analytical approach. In the frame of a general dynamic analysis, it is shown that the onset of instability takes place in the form of divergence (buckling). Then the static forms of instability are investigated, and critical regimes are studied as functions of geometric and mechanical problem param…

research product

Numerical Approximation of Elliptic Variational Problems

This chapter is dedicated to the study of Elliptic Variational Inequalities (EVI). Different forms of such an EVI are considered. The Ritz—Galerkin discretization method is introduced, and methods to approximate the solution of an EVI are presented. The finite dimensional subspaces are built by use of the Finite Element Method. The discretized problems are solved using variants of the Successive OverRelaxation (SOR) method. The algorithms are tested on a typical example. The way to develop computer programs is carefully analysed.

research product

Fusion of technology management and financing management - Amazon's transformative endeavor by orchestrating techno-financing systems

Amazon became the world R&D leader in 2017 by rapidly increasing R&D investment. Its R&D investment in 2017 was double that of 2015, 5 times that of 2012, and 10 times that of 2011. This rapid increase continued in 2018, and Amazon accomplished a skyrocketing increase in its market capitalization, closing to being the world's biggest company. Such a rapid increase in R&D and subsequent market value has raised questions about how to conduct R&D and secure a large amount of funds needed for high-risk investments. Amazon has provided hypothetical answers to both of these questions. Amazon has been conducting innovative R&D to transform routine or periodic alterations into significant improveme…

research product

Overview of Other Results and Open Problems

This chapter presents an overview of results related to error control methods, which were not considered in previous chapters. In the first part, we discuss possible extensions of the theory exposed in Chaps. 3 and 4 to nonconforming approximations and certain classes of nonlinear problems. Also, we shortly discuss some results related to explicit evaluation of modeling errors. The remaining part of the chapter is devoted to a posteriori estimates of errors in iteration methods. Certainly, the overview is not complete. A posteriori error estimation methods are far from having been fully explored and this subject contains many unsolved problems and open questions, some of which we formulate …

research product

Involving the elderly in the content development of a health enhancing tablet-based service

The aim of the present study was to specify the needs of elderly for a health-enhancing tablet-based service. An interview study was performed with voluntary elderly (N=19, female 15, male 4, aged 76.2 years (SD 8.3)). The attitudes towards improving health behaviours and technology utilisation were explored. The content illustrations were developed for the interviews, and evaluated by participants using a numerical scale (1 very poor − 5 very good) and verbal feedback. Content analysis was used in the analysis of qualitative data. Taking care of one's own well-being comprehensively was the most important incentive to maintain one's activity. Content illustrations were evaluated as high (av…

research product

Periodic Discrete Splines

Periodic discrete splines with different periods and spans were introduced in Sect. 3.4. In this chapter, we discuss families of periodic discrete splines, whose periods and spans are powers of 2. As in the polynomial splines case, the Zak transform is extensively employed. It results in the Discrete Spline Harmonic Analysis (DSHA). Utilization of the Fast Fourier transform (FFT) enables us to implement all the computations in a fast explicit way.

research product

Properties of Scattering Matrices in a Vicinity of Thresholds

Chapter 3 is devoted to various properties of a waveguide scattering matrix, which is a matrix function on the waveguide continuous spectrum. There is a sequence of threshold values of the spectral parameter where the scattering matrix changes its size; the thresholds accumulate at infinity. In particular, both two-sided limits of the scattering matrix are calculated at every threshold.

research product

On superconvergence techniques

research product

Yliopistojen tutkintokoulutuksen ja tutkimuksen rahoitus ja tulokset vuosina 2000-2004 ja 2005-2009

research product

Splines Computation by Subdivision

In this chapter, fast stable algorithms are presented, which compute splines’ values at dyadic and triadic rational points starting from their samples at integer grid points. The algorithms are implemented by the causal-anticausal recursive filtering of initial data samples, which is followed by iterated application of FIR filters. Extension of the algorithms to the multidimensional case is straightforward. A natural application of the presented subdivision algorithms is for upsampling of signals and images. A few upsampling examples are provided.

research product

Optimal control for state constrained two-phase Stefan problems

We give a new approach to state constrained control problems associated to non-degenerate nonlinear parabolic equations of Stefan type. We obtain uniform estimates for the violation of the constraints.

research product

Acoustic detection and classification of river boats

We present a robust algorithm to detect the arrival of a boat of a certain type when other background noises are present. It is done via the analysis of its acoustic signature against an existing database of recorded and processed acoustic signals. We characterize the signals by the distribution of their energies among blocks of wavelet packet coefficients. To derive the acoustic signature of the boat of interest, we use the Best Discriminant Basis method. The decision is made by combining the answers from the Linear Discriminant Analysis (LDA) classifier and from the Classification and Regression Trees (CART) that is also accompanied with an additional unit, called Aisles, that reduces fal…

research product

On the Real-Time Simulation and Control of the Continuous Casting Process

Ll this paper we present a method for controlling in real-time the secondary cooling of the continuous casting machine. The method is based on the heat transfer model, which simulates the temperature distribution of the cast, and on the use of direct digital control (DDC). Off-line simulation results considering the control method is presented.

research product

ICT-driven disruptive innovation nurtures un-captured GDP : Harnessing women's potential as untapped resources

The harnessing of untapped resources has become essential for inclusive growth in digital economies particularly as developed economies continue to age demographically. The harnessing of women's potential is an urgent subject in this context, and successive initiatives have been flourishing in many countries. However, given the institutional complexity of the issue, as well as considerable variety across nations, uniformed non-systematic approaches are hardly satisfactory in achieving a timely solution. Against this back drop, this paper analyzed a new information communication technology (ICT)-driven disruptive innovation that may nurture un-captured GDP by harnessing untapped resources su…

research product

Local cubic splines on non-uniform grids and real-time computation of wavelet transform

In this paper, local cubic quasi-interpolating splines on non-uniform grids are described. The splines are designed by fast computational algorithms that utilize the relation between splines and cubic interpolation polynomials. These splines provide an efficient tool for real-time signal processing. As an input, the splines use either clean or noised arbitrarily-spaced samples. Formulas for the spline’s extrapolation beyond the sampling interval are established. Sharp estimations of the approximation errors are presented. The capability to adapt the grid to the structure of an object and to have minimal requirements to the operating memory are of great advantages for offline processing of s…

research product

Semi-discrete Galerkin approximation method applied to initial boundary value problems for Maxwell's equations in anisotropic, inhomogeneous media

SynopsisIn this paper the semi-discrete Galerkin approximation of initial boundary value problems for Maxwell's equations is analysed. For the electric field a hyperbolic system of equations is first derived. The standard Galerkin method is applied to this system and a priori error estimates are established for the approximation.

research product

Social gaming platforms and the gamification of education and learning

research product

Block-Based Inversion of the Heat Equations

This chapter presents robust methods, which refine the algorithms, in Sect. 7.2, for inversion of the heat equations. The idea behind the algorithms is to solve the inversion problem separately in different frequency bands. This is achieved by using spline wavelet packets. The solutions that minimize some parameterized quadratic functionals, are derived as linear combinations of the wavelet packets. Choice of parameters, which is performed automatically, determines the trade-off between the solution regularity and the initial data approximation. The Spline Harmonic Analysis (SHA) technique provides a unified computational scheme for the fast implementation of the algorithm and an explicit r…

research product

Kohti laskennallisen ajattelun osaamista : oppilaiden laaja-alaisen osaamisen edistäminen ja tieto- ja viestintätekniikan opetuskäytön vahvistaminen

research product

Terveys- ja hyvinvointiteknologian sovelluksia ikääntyneiden terveyden edistämisessä ja kustannusvaikuttavien palvelujen kehittämisessä

research product

Real-time simulation and control system for the continuous casting process

In this paper we present a real-time system which is used to simulate the unsteady-state continuous casting process and to control the secondary cooling water sprays. The aim of the control system is to keep the surface temperature of the slab constant with respect to time in spite of casting speed variations, and in this way minimize the formation of cracks in the final product. The simulator calculates the temperature distribution using a mathematical model based on a heat conduction formula with phase changes. The optimal spray water flow rates for each spray cooling zone will be calculated by minimizing the deviation between the target surface temperature and the calculated actual surfa…

research product

GLOBAL DELAY TIME FOR GENERAL DISTRIBUTED NETWORKS WITH APPLICATIONS TO TIMING ANALYSIS OF DIGITAL MOS INTEGRATED CIRCUITS

We consider here a general nerwork composed by n‐distributed parameters lines (with telegraph‐equations models) and m‐capacitors, all connected by a resistive multiport. An asymptotic stability property drives us to define and evaluate a global parameter (“λ‐delay time”) which describes the speed of signals propagation through the network. Because of its simplicity of calculation and its tightness, the given upper bound of the λ‐delay time is useful in timing analysis of MOS integrated chips.

research product

Co-Evolutionary Coupling via a Digital-bio Ecosystem – A Suggestion for a New R&D Model in the Digital Economy

A solution to the critical problem of a dilemma between R&D expansion and productivity decline that a majority of information and communication technology (ICT) leaders have been confronting in the digital economy is expected. It can be expected by a spinoff from economic functionality-seeking GDP-based coevolution cycle to supra-functionality beyond an economic value-seeking uncaptured GDP-driven coevolution cycle. However, the transformation dynamism remains a black box. By means of numerical simulations based on empirical analyses of the development trajectories of global ICT leaders, focusing on Amazon and Finland, together with an intensive review of preceding analyses, this paper atte…

research product

Discretization estimates for an elliptic control problem

An optimal control problem governed by an elliptic equation written in variational form in an abstract functional framework is considered. The control is subject to restrictions. The optimality conditions are established and the Ritz-Galerkin discretization is introduced. If the error estimate corresponding to the elliptic equation is given as a function like where h is the discretization parameter and is an integer, then the error estimates for the optimal control, for the optimal state and for the optimal value are obtained. These results are applied first for a Two-Point BVP and next for a 2D/3D elliptic problem as state equation. Next a spectral method is used in the discretization proc…

research product

Kohti tulevaisuuden tietoyhteiskuntaa : Pääkirjoitus

research product

Participation of the young ones in virtual worlds : A look at experiences and motivations

Virtual worlds have become very popular and there have been some attempts to find the motivations and experiences of using them. The aim of this paper is to analyze the motivations and experiences of young ones to utilize virtual worlds. The paper identifies the activities that children perform in virtual worlds, features they use as well as the reasons for abandoning these virtual worlds. The paper presents results of a qualitative field study. The results indicate that features that are liked in the virtual worlds are similar to games. The most liked features for virtual worlds were developing characters and doing things in groups. The activities that were liked the most in virtual worlds…

research product

Shape optimization in contact problems : Approximation and numerical realization

The optímal shape design of a two-dimensíonal elastic body on rigid foundatíon is analyzed. The relation between the continuous problem and the díscrete problem achieved by FEM is presented. A numerícal realization together wíth the sensítivity analysís is given. Several numerical examples to illustrate the practícal use of the methods are presented. peerReviewed

research product

Identification of critical curves. Part II. Discretization and numerical realization

We consider the finite element approximation of the identification problem, where one wishes to identify a curve along which a given solution of the boundary value problem possesses some specific property. We prove the convergence of FE-approximation and give some results of numerical tests. peerReviewed

research product

A Steepest Descent Method for the Approximation of the Boundary Control in Two-Phase Stefan Problem

research product

On the approximation of the boundary control in two-phase Stefan-type problems

The paper is concerned with boundary control of two-phase Stefan problems. A construction of optimal solutions, based on exploiting regularization techniques, is presented. Results of some numerical experiments are discussed. peerReviewed

research product

Shape optimization in contact problems based on penalization of the state inequality

The paper deals with the approximation of optimal shape of elastic bodies, uni­laterally supported by a rigid, frictionless foundation. Original state inequality, describing the behaviour of such a body is replaced by a family of penalized state problems. The relation between optimal shapes for the original state inequality and those for penalized state equations is established. peerReviewed

research product