Search results for "Complex system"

showing 10 items of 226 documents

FAST OSCILLATING MIGRATIONS IN A PREDATOR-PREY MODEL

1996

The aim of this paper is to give a method which permits us to describe how individual properties can emerge at the population level, in population dynamics. We consider interacting populations. In order to take into account the spatial or behavioral heterogeneity, we subdivide each population into subpopulations. A given subpopulation corresponds to those individuals having the same behavior and who are in a homogeneous environment. Furthermore, we assume that the migration process is faster than the growth and interaction processes. Therefore, we must study models with many variables coupled together into large scaled differential systems. Firstly, our method permits us to reduce these co…

education.field_of_studyPopulation levelProcess (engineering)Computer scienceApplied MathematicsPopulationComplex systemPredationSocial dynamicsOrder (biology)Modeling and SimulationBehavioral heterogeneityStatistical physicseducationMathematical Models and Methods in Applied Sciences
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On the qualitative analysis of the solutions of a mathematical model of social dynamics

2006

Abstract This work deals with a family of dynamical systems which were introduced in [M.L. Bertotti, M. Delitala, From discrete kinetic and stochastic game theory to modelling complex systems in applied sciences, Math. Models Methods Appl. Sci. 7 (2004) 1061–1084], modelling the evolution of a population of interacting individuals, distinguished by their social state. The existence of certain uniform distribution equilibria is proved and the asymptotic trend is investigated.

education.field_of_studyPopulation modelsDynamical systems theoryDiscretizationAsymptotic stabilityApplied MathematicsStochastic gamePopulationComplex systemBoltzmann modelsDynamical systemSocial dynamicsExponential stabilityApplied mathematicseducationKinetic theoryMathematical economicsNonlinearityMathematicsDiscretizationApplied Mathematics Letters
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Evolutionary Dynamics of Inter-firm Networks: A Complex Systems Perspective

2008

This chapter aims to identify the main determinants that define the architectural properties of network emergence and significantly influence the dynamics underlying network evolution in time. The identification and analysis of these determinants, as well as the dynamic processes tied to them, allows to appreciate the competitive bases and consequences of network morphology. To this purpose, using a complex systems perspective as an integrative conceptual approach, we represent networks as complex dynamic systems of knowledge and capabilities. We perform a comparative in-depth analysis of the processes underlying the emergence and evolution of STMicroelectronic's global network and of Toyot…

evolution of interfirm networks complex systems
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Persistence in complex systems

2022

Persistence is an important characteristic of many complex systems in nature, related to how long the system remains at a certain state before changing to a different one. The study of complex systems' persistence involves different definitions and uses different techniques, depending on whether short-term or long-term persistence is considered. In this paper we discuss the most important definitions, concepts, methods, literature and latest results on persistence in complex systems. Firstly, the most used definitions of persistence in short-term and long-term cases are presented. The most relevant methods to characterize persistence are then discussed in both cases. A complete literature r…

fractal dimensionFOS: Computer and information sciencesComplex systemsRenewable energyglobal solar-radiationsystems' statesComplex networksGeneral Physics and AstronomyFOS: Physical scienceslong-term and short-term methodsadaptationzero-temperature dynamicsDynamical Systems (math.DS)Physics - GeophysicsneurosciencememoryMethodology (stat.ME)PersistenceOptimization and planningMemoryMachine learningearthquake magnitude seriesFOS: MathematicsAtmosphere and climateMathematics - Dynamical SystemsAdaptationcomplex systemslow-visibility eventstime-seriesStatistics - Methodologyinflation persistenceLong-term and short-term methodsdetrended fluctuation analysislong-range correlationspersistencecomplex networksSystems’ statesEconomyneural networksrenewable energyGeophysics (physics.geo-ph)atmosphere and climateeconomymachine learningoptimization and planningNeural networkswind-speedNeuroscience
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Defining Complexity Factors for Architecture Evaluation Framework

2006

The design and implementation of telecommunication systems is an incremental and iterative process, and system architectures may need to be revised and refined several times during their lifetime. Formal evaluation facilitates the identification of the weak points, where improvements are due in these architectures. In the domain of telecommunications, such evaluation can be based on the Architecture Evaluation Framework (AEF). During the evaluation, a deep understanding of the processes within a system is needed. Meanwhile, the systems being designed are usually complex systems encompassing a large number of components with an intricate pattern of interaction between them. As a result, it i…

järjestelmäarkkitehtuurijärjestelmäsuunnitteluarviointimenetelmättietoliikennejärjestelmätarchitecture evaluationelinkaaricomplex systems
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All-Possible-Couplings Approach to Measuring Probabilistic Context.

2013

From behavioral sciences to biology to quantum mechanics, one encounters situations where (i) a system outputs several random variables in response to several inputs, (ii) for each of these responses only some of the inputs may "directly" influence them, but (iii) other inputs provide a "context" for this response by influencing its probabilistic relations to other responses. These contextual influences are very different, say, in classical kinetic theory and in the entanglement paradigm of quantum mechanics, which are traditionally interpreted as representing different forms of physical determinism. One can mathematically construct systems with other types of contextuality, whether or not …

lcsh:MedicineQuantum entanglementSocial and Behavioral Sciences01 natural sciencesQuantitative Biology - Quantitative MethodsJoint probability distributionPsychologyStatistical physicslcsh:ScienceQuantumQuantitative Methods (q-bio.QM)60B99 (Primary) 81Q99 91E45 (Secondary)PhysicsQuantum PhysicsMultidisciplinaryApplied MathematicsPhysics05 social sciencesComplex SystemsMental HealthMedicineMathematics - ProbabilityAlgorithmsResearch ArticleFOS: Physical sciencesContext (language use)Physical determinism050105 experimental psychologyProbability theory0103 physical sciencesFOS: Mathematics0501 psychology and cognitive sciences010306 general physicsQuantum MechanicsProbabilityta113BehaviorModels Statisticallcsh:RProbability (math.PR)Probabilistic logicRandom VariablesProbability TheoryKochen–Specker theoremFOS: Biological sciencesQuantum Theorylcsh:QQuantum EntanglementQuantum Physics (quant-ph)Mathematics
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Creating a Framework for Improving the Learnability of a Complex System

2006

When designing complex systems, it is crucial but challenging to make them easy to learn. In this paper, a framework for improving the learnability of a complex system is presented. A classification of factors affecting the learnability of a building modeling system as well as guidelines that refine the factors into practical ways of action are introduced. The factors and guidelines include issues related to the user interface, conformity of the system to user’s expectations, and training. The classification is based on empirical research during which learnability was assessed with several methods. The methodology and the classification of learnability factors can be used as references when…

learnabilityease-of-learningguidelinescomplex systemsgrounded theory
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The balanced digitalization and digital security : Case of regional authorities

2019

The emerging digital infrastructure enables the public authorities to shape their processes and to create attractive digital services for the citizens and the business actors. The public processes, services and infrastructure, however, engage with global and local public and private digital infrastructure and service providers. The complex comprehensiveness of the digital infrastructure and the services challenges the public authorities and create new types of security risks. The achieving of the benefits of the digitalization of public processes and services without increasing security risks requires the adopting of novel approaches to digital security. The paper refers to a framework that…

mallintaminendigital servicescyber securitymodelling of digital securityregionscomplex systemsdigitalisaatiokyberturvallisuussystem modellingjulkiset palvelutaluehallintoverkkopalvelut
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Measuring Functional Connectivity of Human Intra-Cortex Regions with Total Correlation

2021

The economy of brain organization makes the primate brain consume less energy but efficiency. The neurons densely wired each other dependent on both anatomy structure connectivity and functional connectivity. Here, I only describe functional connectivity with Functional Magnetic Resonance Imaging (fMRI) data. Most importantly, how to quantitative measure information share or separate among functional brain regions, what’s worse, fMRI data exist large dimensional problems or “curse dimensionality” [1]. However, the multivariate total correlation method can perfectly address the above problems. In this paper, two things measured with the information-theoretic technique - total correlation [2,…

medicine.diagnostic_testSeries (mathematics)Computer sciencebusiness.industrymedia_common.quotation_subjectComplex systemPattern recognitionPerceptionmedicineTotal correlationArtificial intelligenceEntropy (energy dispersal)Functional magnetic resonance imagingbusinessEnergy (signal processing)Curse of dimensionalitymedia_commonProceedings of Entropy 2021: The Scientific Tool of the 21st Century
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Numerical construction of the density-potential mapping

2018

We demonstrate how a recently developed method Nielsen et al. [Nielsen et al., EPL 101, 33001 (2013)] allows for a comprehensive investigation of time-dependent density functionals in general, and of the exact time-dependent exchange-correlation potential in particular, by presenting the first exact results for two- and three-dimensional multi-electron systems. This method is an explicit realization of the Runge–Gross correspondence, which maps time-dependent densities to their respective potentials, and allows for the exact construction of desired density functionals. We present in detail the numerical requirements that makes this method efficient, stable and precise even for large and rap…

numeeriset menetelmätSolid-state physicstiheysfunktionaaliteoriadensity-potential mappingZero (complex analysis)Complex systemBoundary (topology)02 engineering and technologyState (functional analysis)021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciencesElectronic Optical and Magnetic Materials0103 physical sciencesStatistical physicsBoundary value problem010306 general physics0210 nano-technologyCurrent densityRealization (systems)numerical constructionMathematicsThe European Physical Journal B
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