Search results for " Complex System"

showing 10 items of 32 documents

Epidemic spreading and aging in temporal networks with memory

2018

Time-varying network topologies can deeply influence dynamical processes mediated by them. Memory effects in the pattern of interactions among individuals are also known to affect how diffusive and spreading phenomena take place. In this paper we analyze the combined effect of these two ingredients on epidemic dynamics on networks. We study the susceptible-infected-susceptible (SIS) and the susceptible-infected-removed (SIR) models on the recently introduced activity-driven networks with memory. By means of an activity-based mean-field approach we derive, in the long time limit, analytical predictions for the epidemic threshold as a function of the parameters describing the distribution of …

FOS: Computer and information sciencesPhysics - Physics and SocietyComputer scienceAnalytical predictionsEpidemic dynamicsFOS: Physical sciencesPhysics and Society (physics.soc-ph)Network topology01 natural sciences010305 fluids & plasmasNetworks and Complex Systems0103 physical sciencesQuantitative Biology::Populations and EvolutionStatistical physicsLimit (mathematics)010306 general physicsQuantitative Biology - Populations and EvolutionEpidemic controlSocial and Information Networks (cs.SI)Populations and Evolution (q-bio.PE)Computer Science - Social and Information NetworksFunction (mathematics)Computer Science::Social and Information NetworksArticlesDynamic modelsEpidemic thresholdEpidemic spreadingFOS: Biological sciencesMean field approachPhysical Review. E
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Asymptotic regime in N random interacting species

2005

The asymptotic regime of a complex ecosystem with \emph{N}random interacting species and in the presence of an external multiplicative noise is analyzed. We find the role of the external noise on the long time probability distribution of the i-th density species, the extinction of species and the local field acting on the i-th population. We analyze in detail the transient dynamics of this field and the cavity field, which is the field acting on the $i^{th}$ species when this is absent. We find that the presence or the absence of some population give different asymptotic distributions of these fields.

Fluctuation phenomena random processes noise and Brownian motionPhysicsPhysics - Physics and SocietyFluctuation phenomena random processes noise and Brownian motion; Nonlinear dynamics and nonlinear dynamical systems; Population dynamics and ecological pattern formation; Complex Systemseducation.field_of_studySettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciExtinctionField (physics)PopulationFOS: Physical sciencesComplex SystemsPhysics and Society (physics.soc-ph)External noiseCondensed Matter PhysicsComplex ecosystemMultiplicative noiseElectronic Optical and Magnetic MaterialsProbability distributionQuantitative Biology::Populations and EvolutionStatistical physicsNonlinear dynamics and nonlinear dynamical systemeducationLocal fieldComputer Science::Distributed Parallel and Cluster ComputingPopulation dynamics and ecological pattern formation
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The holonic approach for flexible production: a theoretical framework

2011

This paper discusses the body of knowledge about Holonic Approach to theoretically demonstrate how Holonic Production System (HPS) can be a convincing choice to overcome the problems of traditional production systems? architectures. Today, enterprises are trying to find ways to manage the growing environmental complexity that is well described by Complex Systems Theory (CST). After the focus on the main problem regarding environmental complexity, the Holonic system and the Holonic Production System will be analyzed. The paper will focus the potential of HPS to adapt and react to changes in the business environment whilst being able to maintain systemic synergies and coordination through the…

Holonic production systems Production agility Complex systems Systemic approachSettore SECS-P/08 - Economia E Gestione Delle Imprese
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Households and their Expenditures as an Evolving Complex Social System

2020

Household consumption Complex Systems Statistically Validated NetworksSettore SPS/07 - Sociologia Generale
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EVOLUTIONARY DYNAMICS OF INTERFIRM NETWORKS: A COMPLEX SYSTEM PERSPECTIVE

2008

Interfirm Networks Complex System Evolutionary DynamicsSettore SECS-P/08 - Economia E Gestione Delle Imprese
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Noise stabilization effects in models of interdisciplinary physics

2009

Metastability is a generic feature of many nonlinear systems, and the problem of the lifetime of metastable states involves fundamental aspects of nonequilibrium statistical mechanics. The investigation of noise-induced phenomena in far from equilibrium systems is one of the approaches used to understand the behaviour of physical and biological complex systems. The enhancement of the lifetime of metastable states through the noise enhanced stability effect and the role played by the resonant activation phenomenon will be discussed in models of interdisciplinary physics: (i) polymer translocation dynamics; (ii) transient regime of FitzHugh-Nagumo model; (iii) market stability in a nonlinear …

Josephson effectPhysicsmetastability in quantum systemsHistorystatistical mechanics complex systems noiseSettore FIS/02 - Fisica Teorica Modelli E Metodi MatematiciComplex systemStatistical mechanicsNoise (electronics)noise-induced phenomena; out-of-equilibrium phenomena; metastability in quantum systemsComputer Science ApplicationsEducationHeston modelNonlinear systemMetastabilityStatistical physicsout-of-equilibrium phenomenaQuantumnoise-induced phenomena
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Introduction

2017

The book is devoted to three key questions concerning the relationship between complexity and natural language. Briefly, such questions are: (a) What kind of complexity for natural language? (b) Which theory of language in the perspective of complexity? (c) What sorts of methods and models in the analysis of the observed phenomena? All the essays in this volume show the reference to complexity as a constant element. However, the use of the singular may not be entirely appropriate.

Language Complex System limited recursion gestaltist compositionality semiogenesis.Settore M-FIL/05 - Filosofia E Teoria Dei Linguaggi
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Air Transport Network: a short review

2013

Networks complex systems transport air traffic management
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Role of noise in a market model with stochastic volatility

2006

We study a generalization of the Heston model, which consists of two coupled stochastic differential equations, one for the stock price and the other one for the volatility. We consider a cubic nonlinearity in the first equation and a correlation between the two Wiener processes, which model the two white noise sources. This model can be useful to describe the market dynamics characterized by different regimes corresponding to normal and extreme days. We analyze the effect of the noise on the statistical properties of the escape time with reference to the noise enhanced stability (NES) phenomenon, that is the noise induced enhancement of the lifetime of a metastable state. We observe NES ef…

Noise inducedProbability theory stochastic processes and statisticFOS: Physical sciencesEconomicFOS: Economics and businessStochastic differential equationStatistical physicsMarket modelCondensed Matter - Statistical MechanicsEconomics; econophysics financial markets business and management; Probability theory stochastic processes and statistics; Fluctuation phenomena random processes noise and Brownian motion; Complex SystemsMathematicsFluctuation phenomena random processes noise and Brownian motionStatistical Finance (q-fin.ST)Stochastic volatilityStatistical Mechanics (cond-mat.stat-mech)Cubic nonlinearityQuantitative Finance - Statistical FinanceComplex SystemsWhite noiseDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural NetworksCondensed Matter PhysicsSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Electronic Optical and Magnetic MaterialsHeston modelVolatility (finance)econophysics financial markets business and management
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On-chip quantum frequency combs for complex photon state generation (Conference Presentation)

2020

A key challenge in today’s quantum science is the realization of large-scale complex non-classical systems to enable e.g. ultra-secure communications, quantum-enhanced measurements, and computations faster than classical approaches. Optical frequency combs represent a powerful approach towards this, since they provide a very high number of temporal and frequency modes which can result in large-scale quantum systems. Here, we discuss the recent progress on the realization of integrated quantum frequency combs and reveal how their use in combination with on-chip and fiber-optic telecommunications components can enable quantum state control with new functionalities, yielding unprecedented capa…

PhotonQuantum stateComputer scienceComputationFrequency combs Quantum communications Quantum information Complex systems Control systems Four wave mixing ManufacturingElectronic engineeringKey (cryptography)Settore ING-INF/02 - Campi ElettromagneticiState (computer science)Quantum information scienceRealization (systems)QuantumLaser Resonators, Microresonators, and Beam Control XXII
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