Search results for "discrete [space-time]"
showing 10 items of 2035 documents
Discrete exterior calculus for photonic crystal waveguides
2022
The discrete exterior calculus (DEC) is very promising, though not yet widely used, discretization method for photonic crystal (PC) waveguides. It can be seen as a generalization of the finite difference time domain (FDTD) method. The DEC enables efficient time evolution by construction and fits well for nonhomogeneous computational domains and obstacles of curved surfaces. These properties are typically present in applications of PC waveguides that are constructed as periodic structures of inhomogeneities in a computational domain. We present a two-dimensional DEC discretization for PC waveguides and demonstrate it with a selection of numerical experiments typical in the application area. …
A note on discrete sets
2009
We give several partial positive answers to a question of Juhasz and Szentmiklossy regarding the minimum number of discrete sets required to cover a compact space. We study the relationship between the size of discrete sets, free sequences and their closures with the cardinality of a Hausdorff space, improving known results in the literature.
Statistical properties of general Markov dynamical sources: applications to information theory
2004
In \textitDynamical sources in information theory: fundamental intervals and word prefixes, B. Vallée studies statistical properties of words generated by dynamical sources. This is done using generalized Ruelle operators. The aim of this article is to generalize sources for which the results hold. First, we avoid the use of Grotendieck theory and Fredholm determinants, this allows dynamical sources that cannot be extended to a complex disk or that are not analytic. Second, we consider Markov sources: the language generated by the source over an alphabet \textbfM is not necessarily \textbfM^*.
Discrete cortical representations and their stability in the presence of synaptic turnover
2015
Population imaging in mouse auditory cortex revealed clustering of neural responses to brief complex sounds: the activity of a local population typically falls close to one out of a small number of observed states [1]. These clusters appear to group sets of auditory stimuli into a discrete set of activity patterns and could thereby form the basis for representations of sound categories. However, to be useful for the brain, such representations should be robust against fluctuations in the underlying circuitry, which are significant even in the absences of any explicit learning paradigm [2]. Here we introduce a novel firing rate based circuit model of mouse auditory cortex to study the emerge…
Models of the population playing the Rock-Paper-Scissors game
2018
We consider discrete dynamical systems coming from the models of evolution of populations playing rock - paper - scissors game . Asymptotic behaviour of trajectories of these systems is described, occurrence of the Neimark-Sacker bifurcation and nonexistence of time averages are proved.
A Discrete-Time Hazard Model for Loans: Some Evidence from Italian Banking System
2012
Problem statement: The probability of default, PD, is a crucial probl em for banks. In the last years international accords (Basel, Basel 2 an d Basel 3) have incentived banks to adopt objective s systems to evaluating and monitoring risk of defaul t in order to predict PD for new loans based on borrower's characteristics. The aim of this study i s to introduce a discrete survival model to study t he risk of default and to propose the empirical eviden ce by the Italian banking system. Approach: Survival analysis is used if we are interested in w hether and when an event occurs. In this context th e event occurrence represents a borrower's transition from one state, loan in bonis that is not…
Algorithms and Logic as Programming Primers
2019
To adapt all-immersive digitalization, the Finnish National Curriculum 2014 (FNC-2014) ‘digi-jumps’ by integrating programming into elementary education. However, applying the change to mathematics teachers’ everyday praxis is hindered by a too high-level specification. To elaborate FNC-2014 into more concrete learning targets, we review the computer science syllabi of countries that are well ahead, as well as the education recommendations set by computer science organizations, such as ACM and IEEE. The whole mathematics syllabus should be critically viewed in the light of these recommendations and feedback collected from software professionals and educators. The feedback reveals an imbalan…
Convergence of dynamic programming principles for the $p$-Laplacian
2018
We provide a unified strategy to show that solutions of dynamic programming principles associated to the $p$-Laplacian converge to the solution of the corresponding Dirichlet problem. Our approach includes all previously known cases for continuous and discrete dynamic programming principles, provides new results, and gives a convergence proof free of probability arguments.
Varieties Generated by Certain Models of Reversible Finite Automata
2006
Reversible finite automata with halting states (RFA) were first considered by Ambainis and Freivalds to facilitate the research of Kondacs-Watrous quantum finite automata. In this paper we consider some of the algebraic properties of RFA, namely the varieties these automata generate. Consequently, we obtain a characterization of the boolean closure of the classes of languages recognized by these models.
Toward learning autonomous pallets by using fuzzy rules, applied in a Conwip system
2012
Published version of an article in the journal: The International Journal of Advanced Manufacturing Technology. Also available from the publisher at: http://dx.doi.org/10.1007/s00170-012-4057-8 Nowadays, material planning and control strategies are becoming continuously complex tasks spanning from individual plants to logistic networks. In fact, this is the consequence of increasing intricacy in product variants and their respective convolution in networks’ structures. Customers ask for specific products with individual characteristics that force companies for more clever performances by more flexibility. For doing so, the existing planning and control systems, which work based on central m…