Search results for "complexity"
showing 10 items of 1094 documents
Steady-state and tracking analysis of a robust adaptive filter with low computational cost
2007
This paper analyses a new adaptive algorithm that is robust to impulse noise and has a low computational load [E. Soria, J.D. Martin, A.J. Serrano, J. Calpe, and J. Chambers, A new robust adaptive algorithm with low computacional cost, Electron. Lett. 42 (1) (2006) 60-62]. The algorithm is based on two premises: the use of the cost function often used in independent component analysis and a fuzzy modelling of the hyperbolic tangent function. The steady-state error and tracking capability of the algorithm are analysed using conservation methods [A. Sayed, Fundamentals of Adaptive Filtering, Wiley, New York, 2003], thus verifying the correspondence between theory and experimental results.
String Attractors and Infinite Words
2022
The notion of string attractor has been introduced by Kempa and Prezza (STOC 2018) in the context of Data Compression and it represents a set of positions of a finite word in which all of its factors can be “attracted”. The smallest size γ∗ of a string attractor for a finite word is a lower bound for several repetitiveness measures associated with the most common compression schemes, including BWT-based and LZ-based compressors. The combinatorial properties of the measure γ∗ have been studied in [Mantaci et al., TCS 2021]. Very recently, a complexity measure, called string attractor profile function, has been introduced for infinite words, by evaluating γ∗ on each prefix. Such a measure has…
Analysis of Chromatin Structure and Composition
1989
Introduction Biochemistry, like many other sciences, is currently undergoing increasing specialization which is thought to be unavoidable because of the rapid progress within this field. Obviously education in Biochemistry and Molecular Biology is also affected. Consequently, the student may lose the ability to integrate his knowledge, which should be a requirement during the training of a scientist. The solution to this problem is quite easy in the case of theoretical courses because, here, the lecturer may include several 'integrative lessons' which give a global view of previously explained facts and place them within the general context of the course. However, in practical courses it is…
The Neural Basis of Idea Density During Natural Spoken Language
2019
Idea density (ID) evolved as a quantification of propositional base structure. Besides its function as a measure of linguistic complexity, ID has also been used as an index of general linguistic ability. In order to find the neural basis for the processing of high or low ID during spontaneous speech, a sample of healthy adults was assessed using the functional resonance imaging (fMRI) technique; participants described pictures presented to them while in the scanner. Differential patterns of activation were observed for the low- and high-ID conditions, providing new insights into the processing correlates of ID.
Hierarchical Self-Assembly of Supramolecular Spintronic Modules into 1D- and 2D-Architectures with Emergence of Magnetic Properties
2004
Hierarchical self-assembly of complex supramolecular architectures allows for the emergence of novel properties at each level of complexity. The reaction of the ligand components A and B with Fe II cations generates the (2 K 2) grid-type functional building modules 1 and 2, presenting spin-tran- sition properties and preorganizing an array of coordination sites that sets the stage for a second assembly step. Indeed, binding of La III ions to 1 and of Ag I ions to 2 leads to a 1D columnar superstructure 3 and to a wall-like 2D layer 4, respectively, with concomitant modulation of the magnetic properties of 1 and 2. Thus, to each of the two levels of structural complexity generat- ed by the t…
A sliding mode approach to robust stabilisation of Markovian jump linear time-delay systems with generally incomplete transition rates
2015
Abstract This paper is devoted to investigating the problem of robust sliding mode control for a class of uncertain Markovian jump linear time-delay systems with generally uncertain transition rates (GUTRs). In this GUTR model, each transition rate can be completely unknown or only its estimate value is known. By making use of linear matrix inequalities technique, sufficient conditions are presented to derive the linear switching surface and guarantee the stochastic stability of sliding mode dynamics. A sliding mode control law is developed to drive the state trajectory of the closed-loop system to the specified linear switching surface in a finite-time interval in spite of the existing unc…
On the arithmetic of a family of degree-two K3 surfaces
2018
Let $\mathbb{P}$ denote the weighted projective space with weights $(1,1,1,3)$ over the rationals, with coordinates $x,y,z,$ and $w$; let $\mathcal{X}$ be the generic element of the family of surfaces in $\mathbb{P}$ given by \begin{equation*} X\colon w^2=x^6+y^6+z^6+tx^2y^2z^2. \end{equation*} The surface $\mathcal{X}$ is a K3 surface over the function field $\mathbb{Q}(t)$. In this paper, we explicitly compute the geometric Picard lattice of $\mathcal{X}$, together with its Galois module structure, as well as derive more results on the arithmetic of $\mathcal{X}$ and other elements of the family $X$.
Surface Activity of Humic Substances Within Peat Profile
2012
Humic substances are able to reduce the surface tension of their solutions and thus can act as surface-active substances in natural environment and possibly also for industrial applications. The ability to influence the surface tension of humic substance solutions depends on their origin. The objective of this study is a comparison of the ability of humic substances from peat profile to influence the surface tension of their solutions and identification of the structural characteristics of peat humic acids, determining their surfactant properties. Humic acids isolated from peat demonstrated significant impact of the surface tension of their solutions – they act as weak surfactants. The surf…
A multi-methodology and sustainability-supporting framework for implementation and assessment of a holistic building renovation
La ristrutturazione degli edifici in futuro dovrà essere condotta secondo una prospettiva più olistica legata alla sostenibilità vista in una più ampia gamma di obiettivi/criteri e facilitata dagli scenari di ristrutturazione possibili. La ristrutturazione degli edifici dovrebbe servire a migliorarne le performance al fine di soddisfare le esigenze degli utenti, rendendo questi ultimi meno vulnerabili in relazione ai futuri costi energetici. Vi è un grande potenziale per ridurre il consumo di energia negli edifici esistenti. Tuttavia, ciò non deve comprometterè i valori architettonici e di qualità che rendono particolari. Pertanto, non possono essere semplicemente rinnovati, ma devono subir…
Complexity Theory for a New Managerial Paradigm: A Research Framework
2015
In this work, we supply a theoretical framework of how organizations can embed complexity management and sustainable development into their policies and actions. The proposed framework may lead to a new management paradigm, attempting to link the main concepts of complexity theory, change management, knowledge management, sustainable development, and cybernetics. We highlight how the processes of organizational change have occurred as a result of the move to adapt to the changes in the various global and international business environments and how this transformation has led to the shift toward the present innovation economy. We also point how organizational change needs to deal with sustai…