WorldWideScience

Sample records for agent based models

  1. An Agent Based Classification Model

    CERN Document Server

    Gu, Feng; Greensmith, Julie

    2009-01-01

    The major function of this model is to access the UCI Wisconsin Breast Can- cer data-set[1] and classify the data items into two categories, which are normal and anomalous. This kind of classifi cation can be referred as anomaly detection, which discriminates anomalous behaviour from normal behaviour in computer systems. One popular solution for anomaly detection is Artifi cial Immune Sys- tems (AIS). AIS are adaptive systems inspired by theoretical immunology and observed immune functions, principles and models which are applied to prob- lem solving. The Dendritic Cell Algorithm (DCA)[2] is an AIS algorithm that is developed specifi cally for anomaly detection. It has been successfully applied to intrusion detection in computer security. It is believed that agent-based mod- elling is an ideal approach for implementing AIS, as intelligent agents could be the perfect representations of immune entities in AIS. This model evaluates the feasibility of re-implementing the DCA in an agent-based simulation environ- ...

  2. SAM : Semantic Agent Model for SWRL rule-based agents

    OpenAIRE

    Subercaze, Julien; Maret, Pierre

    2010-01-01

    International audience SemanticWeb technologies are part of multi-agent engineering, especially regarding knowledge base support. Recent advances in the field of logic for the semantic web enable a new range of applications. Among them, programming agents based on semantic rules is a promising field. In this paper we present a semantic agent model that allows SWRL programming of agents. Our approach, based on the extended finite state machine concept, results in a three layers architecture...

  3. Econophysics of agent-based models

    CERN Document Server

    Aoyama, Hideaki; Chakrabarti, Bikas; Chakraborti, Anirban; Ghosh, Asim

    2014-01-01

    The primary goal of this book is to present the research findings and conclusions of physicists, economists, mathematicians and financial engineers working in the field of "Econophysics" who have undertaken agent-based modelling, comparison with empirical studies and related investigations. Most standard economic models assume the existence of the representative agent, who is “perfectly rational” and applies the utility maximization principle when taking action. One reason for this is the desire to keep models mathematically tractable: no tools are available to economists for solving non-linear models of heterogeneous adaptive agents without explicit optimization. In contrast, multi-agent models, which originated from statistical physics considerations, allow us to go beyond the prototype theories of traditional economics involving the representative agent. This book is based on the Econophys-Kolkata VII Workshop, at which many such modelling efforts were presented. In the book, leading researchers in the...

  4. Agent-based modeling and network dynamics

    CERN Document Server

    Namatame, Akira

    2016-01-01

    The book integrates agent-based modeling and network science. It is divided into three parts, namely, foundations, primary dynamics on and of social networks, and applications. The book begins with the network origin of agent-based models, known as cellular automata, and introduce a number of classic models, such as Schelling’s segregation model and Axelrod’s spatial game. The essence of the foundation part is the network-based agent-based models in which agents follow network-based decision rules. Under the influence of the substantial progress in network science in late 1990s, these models have been extended from using lattices into using small-world networks, scale-free networks, etc. The book also shows that the modern network science mainly driven by game-theorists and sociophysicists has inspired agent-based social scientists to develop alternative formation algorithms, known as agent-based social networks. The book reviews a number of pioneering and representative models in this family. Upon the gi...

  5. Spatial interactions in agent-based modeling

    CERN Document Server

    Ausloos, Marcel; Merlone, Ugo

    2014-01-01

    Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution o...

  6. Agent-based pedestrian modelling

    OpenAIRE

    Batty, Michael

    2003-01-01

    When the focus of interest in geographical systems is at the very fine scale, at the level of streets and buildings for example, movement becomes central to simulations of how spatial activities are used and develop. Recent advances in computing power and the acquisition of fine scale digital data now mean that we are able to attempt to understand and predict such phenomena with the focus in spatial modelling changing to dynamic simulations of the individual and collective beha...

  7. An Agent Based Classification Model

    OpenAIRE

    Gu, Feng; Aickelin, Uwe; Greensmith, Julie

    2009-01-01

    The major function of this model is to access the UCI Wisconsin Breast Can- cer data-set[1] and classify the data items into two categories, which are normal and anomalous. This kind of classifi cation can be referred as anomaly detection, which discriminates anomalous behaviour from normal behaviour in computer systems. One popular solution for anomaly detection is Artifi cial Immune Sys- tems (AIS). AIS are adaptive systems inspired by theoretical immunology and observed immune functions, p...

  8. Agent-Based Modeling and Mapping of Manufacturing System

    Institute of Scientific and Technical Information of China (English)

    Z; Zhang

    2002-01-01

    Considering the agent-based modeling and mapping i n manufacturing system, some system models are described in this paper, which are included: Domain Based Hierarchical Structure (DBHS), Cascading Agent Structure (CAS), Proximity Relation Structure (PRS), and Bus-based Network Structure (BNS ). In DBHS, one sort of agents, called static agents, individually acts as Domai n Agents, Resources Agents, UserInterface Agents and Gateway Agents. And the oth ers, named mobile agents, are the brokers of task and ...

  9. Agent-Based Modeling in Systems Pharmacology.

    Science.gov (United States)

    Cosgrove, J; Butler, J; Alden, K; Read, M; Kumar, V; Cucurull-Sanchez, L; Timmis, J; Coles, M

    2015-11-01

    Modeling and simulation (M&S) techniques provide a platform for knowledge integration and hypothesis testing to gain insights into biological systems that would not be possible a priori. Agent-based modeling (ABM) is an M&S technique that focuses on describing individual components rather than homogenous populations. This tutorial introduces ABM to systems pharmacologists, using relevant case studies to highlight how ABM-specific strengths have yielded success in the area of preclinical mechanistic modeling. PMID:26783498

  10. Agent-based Models of Financial Markets

    OpenAIRE

    Samanidou, E.; E. Zschischang; Stauffer, D.; Lux, T.

    2007-01-01

    This review deals with several microscopic (``agent-based'') models of financial markets which have been studied by economists and physicists over the last decade: Kim-Markowitz, Levy-Levy-Solomon, Cont-Bouchaud, Solomon-Weisbuch, Lux-Marchesi, Donangelo-Sneppen and Solomon-Levy-Huang. After an overview of simulation approaches in financial economics, we first give a summary of the Donangelo-Sneppen model of monetary exchange and compare it with related models in economics literature. Our sel...

  11. Agent Based Modelling for Social Simulation

    NARCIS (Netherlands)

    Smit, S.K.; Ubink, E.M.; Vecht, B. van der; Langley, D.J.

    2013-01-01

    This document is the result of an exploratory project looking into the status of, and opportunities for Agent Based Modelling (ABM) at TNO. The project focussed on ABM applications containing social interactions and human factors, which we termed ABM for social simulation (ABM4SS). During the course

  12. Multiscale agent-based consumer market modeling.

    Energy Technology Data Exchange (ETDEWEB)

    North, M. J.; Macal, C. M.; St. Aubin, J.; Thimmapuram, P.; Bragen, M.; Hahn, J.; Karr, J.; Brigham, N.; Lacy, M. E.; Hampton, D.; Decision and Information Sciences; Procter & Gamble Co.

    2010-05-01

    Consumer markets have been studied in great depth, and many techniques have been used to represent them. These have included regression-based models, logit models, and theoretical market-level models, such as the NBD-Dirichlet approach. Although many important contributions and insights have resulted from studies that relied on these models, there is still a need for a model that could more holistically represent the interdependencies of the decisions made by consumers, retailers, and manufacturers. When the need is for a model that could be used repeatedly over time to support decisions in an industrial setting, it is particularly critical. Although some existing methods can, in principle, represent such complex interdependencies, their capabilities might be outstripped if they had to be used for industrial applications, because of the details this type of modeling requires. However, a complementary method - agent-based modeling - shows promise for addressing these issues. Agent-based models use business-driven rules for individuals (e.g., individual consumer rules for buying items, individual retailer rules for stocking items, or individual firm rules for advertizing items) to determine holistic, system-level outcomes (e.g., to determine if brand X's market share is increasing). We applied agent-based modeling to develop a multi-scale consumer market model. We then conducted calibration, verification, and validation tests of this model. The model was successfully applied by Procter & Gamble to several challenging business problems. In these situations, it directly influenced managerial decision making and produced substantial cost savings.

  13. Agent-based Modeling and Mapping of Manufacturing System

    Institute of Scientific and Technical Information of China (English)

    Z; Zhang

    2002-01-01

    Considering the gent-based modeling and mapping in m anufacturing system, in this paper, some system models are described, which are including: Domain Based Hierarchical Structure (DBHS), Cascading Agent Struc ture (CAS), Proximity Relation structure (PRS), and Bus-based network structure (BNS). In DBHS, one sort of agent individually delegates Domain Agents, Res ources Agents, UserInterface Agents and Gateway Agents and the other one is a br oker of tasks and process flow. Static agents representing...

  14. Enhancing the Combat ID Agent Based Model

    OpenAIRE

    Spaans, M.; Petiet, P.J.; Dean, D; Jackson, J.; Bradley, W.; Shan, L. Y.; Ka-Yoon, W.; Yongwei, D.W.; Kai, C.W.

    2007-01-01

    During previous Project Albert and International data Farming Workshops (IDFW) and during discussions between Dstl and TNO, the suitability and feasibility of Agent Based Models (ABMs) to support research on Combat Identification (Combat ID) was examined. The objective of this research is to: Investigate the effect of (a large number of) different variations in Situational Awareness, Situation Awareness (SA), Target Identification (Target ID), Human Factors, and Tactics, Techniques, and Proce...

  15. Agent Based Modeling in Public Administration

    Directory of Open Access Journals (Sweden)

    Osman SEYHAN

    2013-06-01

    Full Text Available This study aims to explore the role of agent based modeling (ABM as a simulation method in analyzing and formulating the policy making processes and modern public management that is under the pressure of information age and socio-politic demands of open societies. ABM is a simulative research method to understand complex adaptive systems (cas from the perspective of its constituent entities. In this study, by employing agent based computing and Netlogo language, twocase studies about organizational design and organizational riskanalyses have been examined. Results revealed that ABM is anefficient platform determining the optimum results from various scenarios in order to understand structures and processes about policy making in both organizational design and risk management. In the future, more researches are needed about understanding role of ABM on understanding and making decision on future of cas especially in conjunction with developments in computer technologies.

  16. Agent Based Model of Livestock Movements

    Science.gov (United States)

    Miron, D. J.; Emelyanova, I. V.; Donald, G. E.; Garner, G. M.

    The modelling of livestock movements within Australia is of national importance for the purposes of the management and control of exotic disease spread, infrastructure development and the economic forecasting of livestock markets. In this paper an agent based model for the forecasting of livestock movements is presented. This models livestock movements from farm to farm through a saleyard. The decision of farmers to sell or buy cattle is often complex and involves many factors such as climate forecast, commodity prices, the type of farm enterprise, the number of animals available and associated off-shore effects. In this model the farm agent's intelligence is implemented using a fuzzy decision tree that utilises two of these factors. These two factors are the livestock price fetched at the last sale and the number of stock on the farm. On each iteration of the model farms choose either to buy, sell or abstain from the market thus creating an artificial supply and demand. The buyers and sellers then congregate at the saleyard where livestock are auctioned using a second price sealed bid. The price time series output by the model exhibits properties similar to those found in real livestock markets.

  17. Agent Based Modeling as an Educational Tool

    Science.gov (United States)

    Fuller, J. H.; Johnson, R.; Castillo, V.

    2012-12-01

    Motivation is a key element in high school education. One way to improve motivation and provide content, while helping address critical thinking and problem solving skills, is to have students build and study agent based models in the classroom. This activity visually connects concepts with their applied mathematical representation. "Engaging students in constructing models may provide a bridge between frequently disconnected conceptual and mathematical forms of knowledge." (Levy and Wilensky, 2011) We wanted to discover the feasibility of implementing a model based curriculum in the classroom given current and anticipated core and content standards.; Simulation using California GIS data ; Simulation of high school student lunch popularity using aerial photograph on top of terrain value map.

  18. Agent-based modeling and simulation

    CERN Document Server

    Taylor, Simon

    2014-01-01

    Operational Research (OR) deals with the use of advanced analytical methods to support better decision-making. It is multidisciplinary with strong links to management science, decision science, computer science and many application areas such as engineering, manufacturing, commerce and healthcare. In the study of emergent behaviour in complex adaptive systems, Agent-based Modelling & Simulation (ABMS) is being used in many different domains such as healthcare, energy, evacuation, commerce, manufacturing and defense. This collection of articles presents a convenient introduction to ABMS with pa

  19. An Agent-Based Monetary Production Simulation Model

    DEFF Research Database (Denmark)

    Bruun, Charlotte

    2006-01-01

    An Agent-Based Simulation Model Programmed in Objective Borland Pascal. Program and source code is downloadable......An Agent-Based Simulation Model Programmed in Objective Borland Pascal. Program and source code is downloadable...

  20. Agent-based models of financial markets

    International Nuclear Information System (INIS)

    This review deals with several microscopic ('agent-based') models of financial markets which have been studied by economists and physicists over the last decade: Kim-Markowitz, Levy-Levy-Solomon, Cont-Bouchaud, Solomon-Weisbuch, Lux-Marchesi, Donangelo-Sneppen and Solomon-Levy-Huang. After an overview of simulation approaches in financial economics, we first give a summary of the Donangelo-Sneppen model of monetary exchange and compare it with related models in economics literature. Our selective review then outlines the main ingredients of some influential early models of multi-agent dynamics in financial markets (Kim-Markowitz, Levy-Levy-Solomon). As will be seen, these contributions draw their inspiration from the complex appearance of investors' interactions in real-life markets. Their main aim is to reproduce (and, thereby, provide possible explanations) for the spectacular bubbles and crashes seen in certain historical episodes, but they lack (like almost all the work before 1998 or so) a perspective in terms of the universal statistical features of financial time series. In fact, awareness of a set of such regularities (power-law tails of the distribution of returns, temporal scaling of volatility) only gradually appeared over the nineties. With the more precise description of the formerly relatively vague characteristics (e.g. moving from the notion of fat tails to the more concrete one of a power law with index around three), it became clear that financial market dynamics give rise to some kind of universal scaling law. Showing similarities with scaling laws for other systems with many interacting sub-units, an exploration of financial markets as multi-agent systems appeared to be a natural consequence. This topic has been pursued by quite a number of contributions appearing in both the physics and economics literature since the late nineties. From the wealth of different flavours of multi-agent models that have appeared up to now, we discuss the Cont

  1. Agent-based models of financial markets

    Science.gov (United States)

    Samanidou, E.; Zschischang, E.; Stauffer, D.; Lux, T.

    2007-03-01

    This review deals with several microscopic ('agent-based') models of financial markets which have been studied by economists and physicists over the last decade: Kim-Markowitz, Levy-Levy-Solomon, Cont-Bouchaud, Solomon-Weisbuch, Lux-Marchesi, Donangelo-Sneppen and Solomon-Levy-Huang. After an overview of simulation approaches in financial economics, we first give a summary of the Donangelo-Sneppen model of monetary exchange and compare it with related models in economics literature. Our selective review then outlines the main ingredients of some influential early models of multi-agent dynamics in financial markets (Kim-Markowitz, Levy-Levy-Solomon). As will be seen, these contributions draw their inspiration from the complex appearance of investors' interactions in real-life markets. Their main aim is to reproduce (and, thereby, provide possible explanations) for the spectacular bubbles and crashes seen in certain historical episodes, but they lack (like almost all the work before 1998 or so) a perspective in terms of the universal statistical features of financial time series. In fact, awareness of a set of such regularities (power-law tails of the distribution of returns, temporal scaling of volatility) only gradually appeared over the nineties. With the more precise description of the formerly relatively vague characteristics (e.g. moving from the notion of fat tails to the more concrete one of a power law with index around three), it became clear that financial market dynamics give rise to some kind of universal scaling law. Showing similarities with scaling laws for other systems with many interacting sub-units, an exploration of financial markets as multi-agent systems appeared to be a natural consequence. This topic has been pursued by quite a number of contributions appearing in both the physics and economics literature since the late nineties. From the wealth of different flavours of multi-agent models that have appeared up to now, we discuss the Cont

  2. Agent-based models of financial markets

    Energy Technology Data Exchange (ETDEWEB)

    Samanidou, E [Department of Economics, University of Kiel, Olshausenstrasse 40, D-24118 Kiel (Germany); Zschischang, E [HSH Nord Bank, Portfolio Mngmt. and Inv., Martensdamm 6, D-24103 Kiel (Germany); Stauffer, D [Institute for Theoretical Physics, Cologne University, D-50923 Koeln (Germany); Lux, T [Department of Economics, University of Kiel, Olshausenstrasse 40, D-24118 Kiel (Germany)

    2007-03-15

    This review deals with several microscopic ('agent-based') models of financial markets which have been studied by economists and physicists over the last decade: Kim-Markowitz, Levy-Levy-Solomon, Cont-Bouchaud, Solomon-Weisbuch, Lux-Marchesi, Donangelo-Sneppen and Solomon-Levy-Huang. After an overview of simulation approaches in financial economics, we first give a summary of the Donangelo-Sneppen model of monetary exchange and compare it with related models in economics literature. Our selective review then outlines the main ingredients of some influential early models of multi-agent dynamics in financial markets (Kim-Markowitz, Levy-Levy-Solomon). As will be seen, these contributions draw their inspiration from the complex appearance of investors' interactions in real-life markets. Their main aim is to reproduce (and, thereby, provide possible explanations) for the spectacular bubbles and crashes seen in certain historical episodes, but they lack (like almost all the work before 1998 or so) a perspective in terms of the universal statistical features of financial time series. In fact, awareness of a set of such regularities (power-law tails of the distribution of returns, temporal scaling of volatility) only gradually appeared over the nineties. With the more precise description of the formerly relatively vague characteristics (e.g. moving from the notion of fat tails to the more concrete one of a power law with index around three), it became clear that financial market dynamics give rise to some kind of universal scaling law. Showing similarities with scaling laws for other systems with many interacting sub-units, an exploration of financial markets as multi-agent systems appeared to be a natural consequence. This topic has been pursued by quite a number of contributions appearing in both the physics and economics literature since the late nineties. From the wealth of different flavours of multi-agent models that have appeared up to now, we

  3. Interaction Protocols in Multi-Agent Systems based on Agent Petri Nets Model

    Directory of Open Access Journals (Sweden)

    Kamel Barkaoui

    2013-08-01

    Full Text Available This paper deals with the modeling of interaction between agents in Multi Agents System (MAS based on Agent Petri Nets (APN. Our models are created based on communicating agents. Indeed, an agent initiating a conversation with other can specify the interaction protocol wishes to follow. The combination of APN and FIPA Protocols schemes leads to a set of deployment formal rules for points where model interaction can be successfully implemented. We introduce some models FIPA standard protocols.

  4. Validating agent based models through virtual worlds.

    Energy Technology Data Exchange (ETDEWEB)

    Lakkaraju, Kiran; Whetzel, Jonathan H.; Lee, Jina; Bier, Asmeret Brooke; Cardona-Rivera, Rogelio E.; Bernstein, Jeremy Ray Rhythm

    2014-01-01

    As the US continues its vigilance against distributed, embedded threats, understanding the political and social structure of these groups becomes paramount for predicting and dis- rupting their attacks. Agent-based models (ABMs) serve as a powerful tool to study these groups. While the popularity of social network tools (e.g., Facebook, Twitter) has provided extensive communication data, there is a lack of ne-grained behavioral data with which to inform and validate existing ABMs. Virtual worlds, in particular massively multiplayer online games (MMOG), where large numbers of people interact within a complex environ- ment for long periods of time provide an alternative source of data. These environments provide a rich social environment where players engage in a variety of activities observed between real-world groups: collaborating and/or competing with other groups, conducting battles for scarce resources, and trading in a market economy. Strategies employed by player groups surprisingly re ect those seen in present-day con icts, where players use diplomacy or espionage as their means for accomplishing their goals. In this project, we propose to address the need for ne-grained behavioral data by acquiring and analyzing game data a commercial MMOG, referred to within this report as Game X. The goals of this research were: (1) devising toolsets for analyzing virtual world data to better inform the rules that govern a social ABM and (2) exploring how virtual worlds could serve as a source of data to validate ABMs established for analogous real-world phenomena. During this research, we studied certain patterns of group behavior to compliment social modeling e orts where a signi cant lack of detailed examples of observed phenomena exists. This report outlines our work examining group behaviors that underly what we have termed the Expression-To-Action (E2A) problem: determining the changes in social contact that lead individuals/groups to engage in a particular behavior

  5. An Active Learning Exercise for Introducing Agent-Based Modeling

    Science.gov (United States)

    Pinder, Jonathan P.

    2013-01-01

    Recent developments in agent-based modeling as a method of systems analysis and optimization indicate that students in business analytics need an introduction to the terminology, concepts, and framework of agent-based modeling. This article presents an active learning exercise for MBA students in business analytics that demonstrates agent-based…

  6. Volatility clustering in agent based market models

    Science.gov (United States)

    Giardina, Irene; Bouchaud, Jean-Philippe

    2003-06-01

    We define and study a market model, where agents have different strategies among which they can choose, according to their relative profitability, with the possibility of not participating to the market. The price is updated according to the excess demand, and the wealth of the agents is properly accounted for. Only two parameters play a significant role: one describes the impact of trading on the price, and the other describes the propensity of agents to be trend following or contrarian. We observe three different regimes, depending on the value of these two parameters: an oscillating phase with bubbles and crashes, an intermittent phase and a stable ‘rational’ market phase. The statistics of price changes in the intermittent phase resembles that of real price changes, with small linear correlations, fat tails and long-range volatility clustering. We discuss how the time dependence of these two parameters spontaneously drives the system in the intermittent region.

  7. A generic testing framework for agent-based simulation models

    OpenAIRE

    Gürcan, Önder; Dikenelli, Oguz; Bernon, Carole

    2013-01-01

    International audience Agent-based modelling and simulation (ABMS) had an increasing attention during the last decade. However, the weak validation and verification of agent-based simulation models makes ABMS hard to trust. There is no comprehensive tool set for verification and validation of agent-based simulation models, which demonstrates that inaccuracies exist and/or reveals the existing errors in the model. Moreover, on the practical side, many ABMS frameworks are in use. In this sen...

  8. Agent Based Modelling and Simulation of Social Processes

    OpenAIRE

    Armano Srbljinovic; Ognjen Skunca

    2003-01-01

    The paper provides an introduction to agent-based modelling and simulation of social processes. Reader is introduced to the worldview underlying agent-based models, some basic terminology, basic properties of agent-based models, as well as to what one can and what cannot expect from such models, particularly when they are applied to social-scientific investigation. Special attention is given to the issues of validation. Classification-ACM-1998: J.4 [Computer Applications]; Social and behavior...

  9. Tutorial on agent-based modeling and simulation. Part 2 : how to model with agents.

    Energy Technology Data Exchange (ETDEWEB)

    Macal, C. M.; North, M. J.; Decision and Information Sciences

    2006-01-01

    Agent-based modeling and simulation (ABMS) is a new approach to modeling systems comprised of interacting autonomous agents. ABMS promises to have far-reaching effects on the way that businesses use computers to support decision-making and researchers use electronic laboratories to do research. Some have gone so far as to contend that ABMS is a new way of doing science. Computational advances make possible a growing number of agent-based applications across many fields. Applications range from modeling agent behavior in the stock market and supply chains, to predicting the spread of epidemics and the threat of bio-warfare, from modeling the growth and decline of ancient civilizations to modeling the complexities of the human immune system, and many more. This tutorial describes the foundations of ABMS, identifies ABMS toolkits and development methods illustrated through a supply chain example, and provides thoughts on the appropriate contexts for ABMS versus conventional modeling techniques.

  10. The Gap of Current Agent Based Simulation Modeling Practices and Feasibility of a Generic Agent Based Simulation Model

    OpenAIRE

    Yim Ling Loo; Alicia Y.C. Tang; Azhana Ahmad

    2015-01-01

    Agent-based modeling had been revolving to be established approach in modeling simulation systems which are used to understand and predict certain real-life scenarios in specific domains. Past researches which are domain-specific caused repetitive building of new models from scratch and restrict replication and reuse because of limitation of models’ description. This paper presents a review of gaps between domain-specific agent-based simulation modeling and the recent practices of agent-based...

  11. Container Terminal Operations Modeling through Multi agent based Simulation

    OpenAIRE

    Ayub, Yasir; Faruki, Usman

    2009-01-01

    This thesis aims to propose a multi-agent based hierarchical model for the operations of container terminals. We have divided our model into four key agents that are involved in each sub processes. The proposed agent allocation policies are recommended for different situations that may occur at a container terminal. A software prototype is developed which implements the hierarchical model. This web based application is used in order to simulate the various processes involved in the following ...

  12. An Emotional Agent Model Based on Granular Computing

    Directory of Open Access Journals (Sweden)

    Jun Hu

    2012-01-01

    Full Text Available Affective computing has a very important significance for fulfilling intelligent information processing and harmonious communication between human being and computers. A new model for emotional agent is proposed in this paper to make agent have the ability of handling emotions, based on the granular computing theory and the traditional BDI agent model. Firstly, a new emotion knowledge base based on granular computing for emotion expression is presented in the model. Secondly, a new emotional reasoning algorithm based on granular computing is proposed. Thirdly, a new emotional agent model based on granular computing is presented. Finally, based on the model, an emotional agent for patient assistant in hospital is realized, experiment results show that it is efficient to handle simple emotions.

  13. Agent-Based Modeling of Growth Processes

    Science.gov (United States)

    Abraham, Ralph

    2014-01-01

    Growth processes abound in nature, and are frequently the target of modeling exercises in the sciences. In this article we illustrate an agent-based approach to modeling, in the case of a single example from the social sciences: bullying.

  14. Modeling collective emotions: a stochastic approach based on Brownian agents

    International Nuclear Information System (INIS)

    We develop a agent-based framework to model the emergence of collective emotions, which is applied to online communities. Agents individual emotions are described by their valence and arousal. Using the concept of Brownian agents, these variables change according to a stochastic dynamics, which also considers the feedback from online communication. Agents generate emotional information, which is stored and distributed in a field modeling the online medium. This field affects the emotional states of agents in a non-linear manner. We derive conditions for the emergence of collective emotions, observable in a bimodal valence distribution. Dependent on a saturated or a super linear feedback between the information field and the agent's arousal, we further identify scenarios where collective emotions only appear once or in a repeated manner. The analytical results are illustrated by agent-based computer simulations. Our framework provides testable hypotheses about the emergence of collective emotions, which can be verified by data from online communities. (author)

  15. The fractional volatility model: An agent-based interpretation

    Science.gov (United States)

    Vilela Mendes, R.

    2008-06-01

    Based on the criteria of mathematical simplicity and consistency with empirical market data, a model with volatility driven by fractional noise has been constructed which provides a fairly accurate mathematical parametrization of the data. Here, some features of the model are reviewed and extended to account for leverage effects. Using agent-based models, one tries to find which agent strategies and (or) properties of the financial institutions might be responsible for the features of the fractional volatility model.

  16. Social scientists, qualitative data, and agent-based modeling

    OpenAIRE

    Seidl, Roman

    2014-01-01

    Empirical data obtained with social science methods can be useful for informing agent-based models, for instance, to fix the profile of heterogeneous agents or to specify behavioral rules. For the latter in particular, qualitative methods that investigate the details of individual decision processes are an option. In this paper, I highlight the challenges for social scientists who investigate social/psychological phenomena but at the same time have to consider the properties of agent-based si...

  17. MODEL-BASED PERFORMANCE EVALUATION APPROACH FOR MOBILE AGENT SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Li Xin; Mi Zhengkun; Meng Xudong

    2004-01-01

    Claimed as the next generation programming paradigm, mobile agent technology has attracted extensive interests in recent years. However, up to now, limited research efforts have been devoted to the performance study of mobile agent system and most of these researches focus on agent behavior analysis resulting in that models are hard to apply to mobile agent systems. To bridge the gap, a new performance evaluation model derived from operation mechanisms of mobile agent platforms is proposed. Details are discussed for the design of companion simulation software, which can provide the system performance such as response time of platform to mobile agent. Further investigation is followed on the determination of model parameters. Finally comparison is made between the model-based simulation results and measurement-based real performance of mobile agent systems. The results show that the proposed model and designed software are effective in evaluating performance characteristics of mobile agent systems. The proposed approach can also be considered as the basis of performance analysis for large systems composed of multiple mobile agent platforms.

  18. An Agent-Based Modeling for Pandemic Influenza in Egypt

    CERN Document Server

    Khalil, Khaled M; Nazmy, Taymour T; Salem, Abdel-Badeeh M

    2010-01-01

    Pandemic influenza has great potential to cause large and rapid increases in deaths and serious illness. The objective of this paper is to develop an agent-based model to simulate the spread of pandemic influenza (novel H1N1) in Egypt. The proposed multi-agent model is based on the modeling of individuals' interactions in a space time context. The proposed model involves different types of parameters such as: social agent attributes, distribution of Egypt population, and patterns of agents' interactions. Analysis of modeling results leads to understanding the characteristics of the modeled pandemic, transmission patterns, and the conditions under which an outbreak might occur. In addition, the proposed model is used to measure the effectiveness of different control strategies to intervene the pandemic spread.

  19. Agent-based models and individualism: is the world agent-based?

    OpenAIRE

    O'Sullivan, D.; Haklay, M.

    2000-01-01

    Agent-based models (ABMs) are an increasingly popular tool in the social sciences. This trend seems likely to continue, so that they will become widely used in geography and in urban and regional planning. We present an overview of examples of these models in the life sciences, economics, planning, sociology, and archaeology. We conclude that ABMs strongly tend towards an individualist view of the social world. This point is reinforced by closer consideration of particular examples. This disc...

  20. Agent-Based Modeling: A Powerful Tool for Tourism Researchers

    NARCIS (Netherlands)

    Nicholls, Sarah; Amelung, B.; Student, Jillian

    2016-01-01

    Agent-based modeling (ABM) is a way of representing complex systems of autonomous agents or actors, and of simulating the multiple potential outcomes of these agents’ behaviors and interactions in the form of a range of alternatives or futures. Despite the complexity of the tourism system, and the p

  1. Tutorial on agent-based modeling and simulation.

    Energy Technology Data Exchange (ETDEWEB)

    Macal, C. M.; North, M. J.; Decision and Information Sciences

    2005-01-01

    Agent-based modeling and simulation (ABMS) is a new approach to modeling systems comprised of autonomous, interacting agents. ABMS promises to have far-reaching effects on the way that businesses use computers to support decision-making and researchers use electronic laboratories to support their research. Some have gone so far as to contend that ABMS is a third way of doing science besides deductive and inductive reasoning. Computational advances have made possible a growing number of agent-based applications in a variety of fields. Applications range from modeling agent behavior in the stock market and supply chains, to predicting the spread of epidemics and the threat of bio-warfare, from modeling consumer behavior to understanding the fall of ancient civilizations, to name a few. This tutorial describes the theoretical and practical foundations of ABMS, identifies toolkits and methods for developing ABMS models, and provides some thoughts on the relationship between ABMS and traditional modeling techniques.

  2. Agent-based Models for Economic Policy Design

    OpenAIRE

    Dawid, Herbert; Neugart, Michael

    2010-01-01

    Agent-based simulation models are used by an increasing number of scholars as a tool for providing evaluations of economic policy measures and policy recommendations in complex environments. On the basis of recent work in this area we discuss the advantages of agent-based modeling for economic policy design and identify further needs to be addressed for strengthening this methodological approach as a basis for sound policy advice.

  3. Agent-based Model Construction in Financial Economic System

    OpenAIRE

    Hokky Situngkir; Yohanes Surya

    2004-01-01

    The paper gives picture of enrichment to economic and financial system analysis using agent-based models as a form of advanced study for financial economic data post-statistical-data analysis and micro- simulation analysis. Theoretical exploration is carried out by using comparisons of some usual financial economy system models frequently and popularly used in econophysics and computational finance. Primitive model, which consists of agent microsimulation with fundamentalist strategy, chartis...

  4. Agent-Based Approaches for Behavioural Modelling in Military Simulations

    Directory of Open Access Journals (Sweden)

    Gaurav Chaudhary

    2015-12-01

    Full Text Available Behavioral modeling of combat entities in military simulations by creating synthetic agents in order to satisfy various battle scenarios is an important problem. The conventional modeling tools are not always sufficient to handle complex situations requiring adaptation. To deal with this Agent-Based Modeling (ABM is employed, as the agents exhibit autonomous behavior by adapting and varying their behavior during the course of the simulation whilst achieving the goals. Synthetic agents created by means of Computer Generated Force (CGF is a relatively recent approach to model behavior of combat entities for a more realistic training and effective military planning. CGFs, are also sometimes referred to as Semi- Automated Forces (SAF and enables to create high-fidelity simulations. Agents are used to control and augment the behavior of CGF entities, hence converting them into Intelligent CGF (ICGF. The intelligent agents can be modeled to exhibit cognitive abilities. For this review paper, extensive papers on stateof-the-art in agent-based modeling approaches and applications were surveyed. The paper assimilates issues involved in ABM with CGF as an important component of it. It reviews modeling aspects with respect to the interrelationship between ABM and CGF, which is required to carry out behavioral modeling. Important CGFs have been examined and a list with their significant features is given. Another issue that has been reviewed is that how the synthetic agents having different capabilities are implemented at different battle levels. Brief mention of state-of-the-art integrated cognitive architectures and a list of significant cognitive applications based on them with their features is given. At the same time, the maturity of ABM in agent-based applications has also been considered.

  5. Agent Based Reasoning in Multilevel Flow Modeling

    DEFF Research Database (Denmark)

    Lind, Morten; Zhang, Xinxin

    2012-01-01

    Multilevel Flow Modeling (MFM) is a modeling method used for modeling complex industrial plant. Currently, MFM is supported with a standalone software tool called MFM Workbench, which is equipped with causal-relation analysis and other functionalities. The aim of this paper is to offer a new design...

  6. An Agent Operationalization Approach for Context Specific Agent-Based Modeling

    OpenAIRE

    Christof Knoeri; Binder, Claudia R.; Hans-Joerg Althaus

    2011-01-01

    The potential of agent-based modeling (ABM) has been demonstrated in various research fields. However, three major concerns limit the full exploitation of ABM; (i) agents are too simple and behave unrealistically without any empirical basis, (ii) 'proof of concept' applications are too theoretical and (iii) too much value placed on operational validity instead of conceptual validity. This paper presents an operationalization approach to determine the key system agents, their interaction, deci...

  7. Agent-based modelling of socio-technical systems

    CERN Document Server

    van Dam, Koen H; Lukszo, Zofia

    2012-01-01

    Here is a practical introduction to agent-based modelling of socio-technical systems, based on methodology developed at TU Delft, which has been deployed in a number of case studies. Offers theory, methods and practical steps for creating real-world models.

  8. Agent-based modeling and simulation Part 3 : desktop ABMS.

    Energy Technology Data Exchange (ETDEWEB)

    Macal, C. M.; North, M. J.; Decision and Information Sciences

    2007-01-01

    Agent-based modeling and simulation (ABMS) is a new approach to modeling systems comprised of autonomous, interacting agents. ABMS promises to have far-reaching effects on the way that businesses use computers to support decision-making and researchers use electronic laboratories to support their research. Some have gone so far as to contend that ABMS 'is a third way of doing science,' in addition to traditional deductive and inductive reasoning (Axelrod 1997b). Computational advances have made possible a growing number of agent-based models across a variety of application domains. Applications range from modeling agent behavior in the stock market, supply chains, and consumer markets, to predicting the spread of epidemics, the threat of bio-warfare, and the factors responsible for the fall of ancient civilizations. This tutorial describes the theoretical and practical foundations of ABMS, identifies toolkits and methods for developing agent models, and illustrates the development of a simple agent-based model of shopper behavior using spreadsheets.

  9. A role based coordination model in agent systems

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ya-ying; YOU Jin-yuan

    2005-01-01

    Coordination technology addresses the construction of open, flexible systems from active and independent software agents in concurrent and distributed systems. In most open distributed applications, multiple agents need interaction and communication to achieve their overall goal. Coordination technologies for the Internet typically are concerned with enabling interaction among agents and helping them cooperate with each other.At the same time, access control should also be considered to constrain interaction to make it harmless. Access control should be regarded as the security counterpart of coordination. At present, the combination of coordination and access control remains an open problem. Thus, we propose a role based coordination model with policy enforcement in agent application systems. In this model, coordination is combined with access control so as to fully characterize the interactions in agent systems. A set of agents interacting with each other for a common global system task constitutes a coordination group. Role based access control is applied in this model to prevent unauthorized accesses. Coordination policy is enforced in a distributed manner so that the model can be applied to the open distributed systems such as Intemet. An Internet online auction system is presented as a case study to illustrate the proposed coordination model and finally the performance analysis of the model is introduced.

  10. Cognitive Modeling for Agent-Based Simulation of Child Maltreatment

    Science.gov (United States)

    Hu, Xiaolin; Puddy, Richard

    This paper extends previous work to develop cognitive modeling for agent-based simulation of child maltreatment (CM). The developed model is inspired from parental efficacy, parenting stress, and the theory of planned behavior. It provides an explanatory, process-oriented model of CM and incorporates causality relationship and feedback loops from different factors in the social ecology in order for simulating the dynamics of CM. We describe the model and present simulation results to demonstrate the features of this model.

  11. UML MODELING AND SYSTEM ARCHITECTURE FOR AGENT BASED INFORMATION RETRIEVAL

    Directory of Open Access Journals (Sweden)

    D. Muhammad Noorul Mubarak

    2015-12-01

    Full Text Available In this current technological era, there is an enormous increase in the information available on web and also in the online databases. This information abundance increases the complexity of finding relevant information. To solve such challenges, there is a need for improved and intelligent systems for efficient search and retrieval. Intelligent Agents can be used for better search and information retrieval in a document collection. The information required by a user is scattered in a large number of databases. In this paper, the object oriented modeling for agent based information retrieval system is presented. The paper also discusses the framework of agent architecture for obtaining the best combination terms that serve as an input query to the information retrieval system. The communication and cooperation among the agents are also explained. Each agent has a task to perform in information retrieval.

  12. Agent-based Modeling with MATSim for Hazards Evacuation Planning

    Science.gov (United States)

    Jones, J. M.; Ng, P.; Henry, K.; Peters, J.; Wood, N. J.

    2015-12-01

    Hazard evacuation planning requires robust modeling tools and techniques, such as least cost distance or agent-based modeling, to gain an understanding of a community's potential to reach safety before event (e.g. tsunami) arrival. Least cost distance modeling provides a static view of the evacuation landscape with an estimate of travel times to safety from each location in the hazard space. With this information, practitioners can assess a community's overall ability for timely evacuation. More information may be needed if evacuee congestion creates bottlenecks in the flow patterns. Dynamic movement patterns are best explored with agent-based models that simulate movement of and interaction between individual agents as evacuees through the hazard space, reacting to potential congestion areas along the evacuation route. The multi-agent transport simulation model MATSim is an agent-based modeling framework that can be applied to hazard evacuation planning. Developed jointly by universities in Switzerland and Germany, MATSim is open-source software written in Java and freely available for modification or enhancement. We successfully used MATSim to illustrate tsunami evacuation challenges in two island communities in California, USA, that are impacted by limited escape routes. However, working with MATSim's data preparation, simulation, and visualization modules in an integrated development environment requires a significant investment of time to develop the software expertise to link the modules and run a simulation. To facilitate our evacuation research, we packaged the MATSim modules into a single application tailored to the needs of the hazards community. By exposing the modeling parameters of interest to researchers in an intuitive user interface and hiding the software complexities, we bring agent-based modeling closer to practitioners and provide access to the powerful visual and analytic information that this modeling can provide.

  13. Model-Drive Architecture for Agent-Based Systems

    Science.gov (United States)

    Gradanin, Denis; Singh, H. Lally; Bohner, Shawn A.; Hinchey, Michael G.

    2004-01-01

    The Model Driven Architecture (MDA) approach uses a platform-independent model to define system functionality, or requirements, using some specification language. The requirements are then translated to a platform-specific model for implementation. An agent architecture based on the human cognitive model of planning, the Cognitive Agent Architecture (Cougaar) is selected for the implementation platform. The resulting Cougaar MDA prescribes certain kinds of models to be used, how those models may be prepared and the relationships of the different kinds of models. Using the existing Cougaar architecture, the level of application composition is elevated from individual components to domain level model specifications in order to generate software artifacts. The software artifacts generation is based on a metamodel. Each component maps to a UML structured component which is then converted into multiple artifacts: Cougaar/Java code, documentation, and test cases.

  14. Modeling and simulation of complex systems a framework for efficient agent-based modeling and simulation

    CERN Document Server

    Siegfried, Robert

    2014-01-01

    Robert Siegfried presents a framework for efficient agent-based modeling and simulation of complex systems. He compares different approaches for describing structure and dynamics of agent-based models in detail. Based on this evaluation the author introduces the "General Reference Model for Agent-based Modeling and Simulation" (GRAMS). Furthermore he presents parallel and distributed simulation approaches for execution of agent-based models -from small scale to very large scale. The author shows how agent-based models may be executed by different simulation engines that utilize underlying hard

  15. An Agent-Based Dialogical Model with Fuzzy Attitudes

    OpenAIRE

    Piter Dykstra; Wander Jager; Corinna Elsenbroich; Rineke Verbrugge; Gerard Renardel de Lavalette

    2015-01-01

    This paper presents an extension to an agent-based model of opinion dynamics built on dialogical logic DIAL. The extended model tackles a pervasive problem in argumentation logics: the difference between linguistic and logical inconsistency. Using fuzzy logic, the linear ordering of opinions, used in DIAL, is replaced by a set of partial orderings leading to a new, nonstandard notion of consistency as convexity of sets of statements. DIAL allows the modelling of the interplay of social struct...

  16. An Agent Based Model for Social Class Emergence

    Science.gov (United States)

    Yang, Xiaoxiang; Rodriguez Segura, Daniel; Lin, Fei; Mazilu, Irina

    We present an open system agent-based model to analyze the effects of education and the society-specific wealth transactions on the emergence of social classes. Building on previous studies, we use realistic functions to model how years of education affect the income level. Numerical simulations show that the fraction of an individual's total transactions that is invested rather than consumed can cause wealth gaps between different income brackets in the long run. In an attempt to incorporate the network effects, we also explore how the probability of interactions among agents depending on the spread of their income brackets affects wealth distribution.

  17. Multi-level agent-based modeling - Bibliography

    CERN Document Server

    Morvan, Gildas

    2012-01-01

    This very short article aims to bring together the available bibliography on multi-level (or multi-layer, multi-perspective, multi-view, multi-scale, multi-resolution) agent-based modeling so that it is accessible to interested researchers.

  18. Empirical agent-based modelling challenges and solutions

    CERN Document Server

    Barreteau, Olivier

    2014-01-01

    This instructional book showcases techniques to parameterise human agents in empirical agent-based models (ABM). In doing so, it provides a timely overview of key ABM methodologies and the most innovative approaches through a variety of empirical applications.  It features cutting-edge research from leading academics and practitioners, and will provide a guide for characterising and parameterising human agents in empirical ABM.  In order to facilitate learning, this text shares the valuable experiences of other modellers in particular modelling situations. Very little has been published in the area of empirical ABM, and this contributed volume will appeal to graduate-level students and researchers studying simulation modeling in economics, sociology, ecology, and trans-disciplinary studies, such as topics related to sustainability. In a similar vein to the instruction found in a cookbook, this text provides the empirical modeller with a set of 'recipes'  ready to be implemented. Agent-based modeling (AB...

  19. From agent-based models to artificial economies

    OpenAIRE

    Teglio, Andrea

    2011-01-01

    The aim of this thesis is to propose and illustrate an alternative approach to economic modeling and policy design that is grounded in the innovative field of agent-based computational economics (ACE). The recent crisis pointed out the fundamental role played by macroeconomic policy design in order to preserve social welfare, and the consequent necessity of understanding the effects of coordinated policy measures on the economic system. Classic approaches to macroeconomic modeling, mainly rep...

  20. Multispace Behavioral Model for Face-Based Affective Social Agents

    OpenAIRE

    Ali Arya; Steve DiPaola

    2007-01-01

    This paper describes a behavioral model for affective social agents based on three independent but interacting parameter spaces: knowledge, personality, and mood. These spaces control a lower-level geometry space that provides parameters at the facial feature level. Personality and mood use findings in behavioral psychology to relate the perception of personality types and emotional states to the facial actions and expressions through two-dimensional models for personality and emotion. Knowl...

  1. Online analysis and visualization of agent based models

    OpenAIRE

    Grignard, Arnaud; Drogoul, Alexis; Zucker, Jean-Daniel

    2013-01-01

    International audience Agent-based modeling is used to study many kind of complex systems in different fields such as biology, ecology, or sociology. Visualization of the execution of a such complex systems is crucial in the capacity to apprehend its dynamics. The ever increasing complexification of requirements asked by the modeller has highlighted the need for more powerful tools than the existing ones to represent, visualize and interact with a simulation and extract data online to disc...

  2. Agent Based Model of Young Researchers in Higher Education Institutions

    OpenAIRE

    Josip Stepanic; Mirjana Pejic Bach; Josip Kasac

    2013-01-01

    Group of young researchers in higher education institutions in general perform demandable tasks with relatively high contribution to institutions’ and societies’ innovation production. In order to analyse in more details interaction among young researchers and diverse institutions in society, we aim toward developing the numerical simulation, agent-based model. This article presents foundations of the model, preliminary results of its simulation along with perspectives of its further deve...

  3. Agent-Based Deterministic Modeling of the Bone Marrow Homeostasis.

    Science.gov (United States)

    Kurhekar, Manish; Deshpande, Umesh

    2016-01-01

    Modeling of stem cells not only describes but also predicts how a stem cell's environment can control its fate. The first stem cell populations discovered were hematopoietic stem cells (HSCs). In this paper, we present a deterministic model of bone marrow (that hosts HSCs) that is consistent with several of the qualitative biological observations. This model incorporates stem cell death (apoptosis) after a certain number of cell divisions and also demonstrates that a single HSC can potentially populate the entire bone marrow. It also demonstrates that there is a production of sufficient number of differentiated cells (RBCs, WBCs, etc.). We prove that our model of bone marrow is biologically consistent and it overcomes the biological feasibility limitations of previously reported models. The major contribution of our model is the flexibility it allows in choosing model parameters which permits several different simulations to be carried out in silico without affecting the homeostatic properties of the model. We have also performed agent-based simulation of the model of bone marrow system proposed in this paper. We have also included parameter details and the results obtained from the simulation. The program of the agent-based simulation of the proposed model is made available on a publicly accessible website. PMID:27340402

  4. Markov chain aggregation for agent-based models

    CERN Document Server

    Banisch, Sven

    2016-01-01

    This self-contained text develops a Markov chain approach that makes the rigorous analysis of a class of microscopic models that specify the dynamics of complex systems at the individual level possible. It presents a general framework of aggregation in agent-based and related computational models, one which makes use of lumpability and information theory in order to link the micro and macro levels of observation. The starting point is a microscopic Markov chain description of the dynamical process in complete correspondence with the dynamical behavior of the agent-based model (ABM), which is obtained by considering the set of all possible agent configurations as the state space of a huge Markov chain. An explicit formal representation of a resulting “micro-chain” including microscopic transition rates is derived for a class of models by using the random mapping representation of a Markov process. The type of probability distribution used to implement the stochastic part of the model, which defines the upd...

  5. Agent-based modelling of shifting cultivation field patterns, Vietnam

    DEFF Research Database (Denmark)

    Jepsen, Martin Rudbeck; Leisz, S.; Rasmussen, K.;

    2006-01-01

    modelling, and relying on empirical data from fieldwork and observations for parameterization of variables, the level of clustering in agricultural fields observed around a study village is reproduced. Agents in the model act to maximize labour productivity, which is based on potential yield and labour......Shifting cultivation in the Nghe An Province of Vietnam's Northern Mountain Region produces a characteristic land-cover pattern of small and larger fields. The pattern is the result of farmers cultivating either individually or in spatially clustered groups. Using spatially explicit agent-based...... costs associated with fencing of fields, and are faced with physical constraints. The simulation results are compared with land-cover data obtained from remote sensing. Comparisons are made on patterns as detected visually and using the mean nearest-neighbour ratio. Baseline simulation outputs show high...

  6. Simulation of convoy of unmanned vehicles using agent based modeling

    Science.gov (United States)

    Sharma, Sharad; Singh, Harpreet; Gerhart, G. R.

    2007-10-01

    There has been an increasing interest of unmanned vehicles keeping the importance of defense and security. A few models for a convoy of unmanned vehicle exist in literature. The objective of this paper is to exploit agent based modeling technique for a convoy of unmanned vehicles where each vehicle is an agent. Using this approach, the convoy of vehicles reaches a specified goal from a starting point. Each agent is associated with number of sensors. The agents make intelligent decisions based on sensor inputs and at the same time maintaining their group capability and behavior. The simulation is done for a battlefield environment from a single starting point to a single goal. This approach can be extended for multiple starting points to reach multiple goals. The simulation gives the time taken by the convoy to reach a goal from its initial position. In the battlefield environment, commanders make various tactical decisions depending upon the location of an enemy outpost, minefields, number of soldiers in platoons, and barriers. The simulation can help the commander to make effective decisions depending on battlefield, convoy and obstacles to reach a particular goal. The paper describes the proposed approach and gives the simulation results. The paper also gives problems for future research in this area.

  7. Endogenizing geopolitical boundaries with agent-based modeling

    Science.gov (United States)

    Cederman, Lars-Erik

    2002-01-01

    Agent-based modeling promises to overcome the reification of actors. Whereas this common, but limiting, assumption makes a lot of sense during periods characterized by stable actor boundaries, other historical junctures, such as the end of the Cold War, exhibit far-reaching and swift transformations of actors' spatial and organizational existence. Moreover, because actors cannot be assumed to remain constant in the long run, analysis of macrohistorical processes virtually always requires “sociational” endogenization. This paper presents a series of computational models, implemented with the software package REPAST, which trace complex macrohistorical transformations of actors be they hierarchically organized as relational networks or as collections of symbolic categories. With respect to the former, dynamic networks featuring emergent compound actors with agent compartments represented in a spatial grid capture organizational domination of the territorial state. In addition, models of “tagged” social processes allows the analyst to show how democratic states predicate their behavior on categorical traits. Finally, categorical schemata that select out politically relevant cultural traits in ethnic landscapes formalize a constructivist notion of national identity in conformance with the qualitative literature on nationalism. This “finite-agent method”, representing both states and nations as higher-level structures superimposed on a lower-level grid of primitive agents or cultural traits, avoids reification of agency. Furthermore, it opens the door to explicit analysis of entity processes, such as the integration and disintegration of actors as well as boundary transformations. PMID:12011409

  8. Endogenizing geopolitical boundaries with agent-based modeling.

    Science.gov (United States)

    Cederman, Lars-Erik

    2002-05-14

    Agent-based modeling promises to overcome the reification of actors. Whereas this common, but limiting, assumption makes a lot of sense during periods characterized by stable actor boundaries, other historical junctures, such as the end of the Cold War, exhibit far-reaching and swift transformations of actors' spatial and organizational existence. Moreover, because actors cannot be assumed to remain constant in the long run, analysis of macrohistorical processes virtually always requires "sociational" endogenization. This paper presents a series of computational models, implemented with the software package REPAST, which trace complex macrohistorical transformations of actors be they hierarchically organized as relational networks or as collections of symbolic categories. With respect to the former, dynamic networks featuring emergent compound actors with agent compartments represented in a spatial grid capture organizational domination of the territorial state. In addition, models of "tagged" social processes allows the analyst to show how democratic states predicate their behavior on categorical traits. Finally, categorical schemata that select out politically relevant cultural traits in ethnic landscapes formalize a constructivist notion of national identity in conformance with the qualitative literature on nationalism. This "finite-agent method", representing both states and nations as higher-level structures superimposed on a lower-level grid of primitive agents or cultural traits, avoids reification of agency. Furthermore, it opens the door to explicit analysis of entity processes, such as the integration and disintegration of actors as well as boundary transformations. PMID:12011409

  9. Deep Learning in Agent-Based Models: A Prospectus

    OpenAIRE

    Hoog, Sander van der

    2016-01-01

    A very timely issue for economic agent-based models (ABMs) is their empirical estimation. This paper describes a line of research that could resolve the issue by using machine learning techniques, using multi-layer artificial neural networks (ANNs), or so called Deep Nets. The seminal contribution by Hinton et al. (2006) introduced a fast and efficient training algorithm called Deep Learning, and there have been major breakthroughs in machine learning ever since. Economics has not yet benefit...

  10. Statistical Agent Based Modelization of the Phenomenon of Drug Abuse

    Science.gov (United States)

    di Clemente, Riccardo; Pietronero, Luciano

    2012-07-01

    We introduce a statistical agent based model to describe the phenomenon of drug abuse and its dynamical evolution at the individual and global level. The agents are heterogeneous with respect to their intrinsic inclination to drugs, to their budget attitude and social environment. The various levels of drug use were inspired by the professional description of the phenomenon and this permits a direct comparison with all available data. We show that certain elements have a great importance to start the use of drugs, for example the rare events in the personal experiences which permit to overcame the barrier of drug use occasionally. The analysis of how the system reacts to perturbations is very important to understand its key elements and it provides strategies for effective policy making. The present model represents the first step of a realistic description of this phenomenon and can be easily generalized in various directions.

  11. Statistical Agent Based Modelization of the Phenomenon of Drug Abuse

    CERN Document Server

    Di Clemente, Riccardo; 10.1038/srep00532

    2012-01-01

    We introduce a statistical agent based model to describe the phenomenon of drug abuse and its dynamical evolution at the individual and global level. The agents are heterogeneous with respect to their intrinsic inclination to drugs, to their budget attitude and social environment. The various levels of drug use were inspired by the professional description of the phenomenon and this permits a direct comparison with all available data. We show that certain elements have a great importance to start the use of drugs, for example the rare events in the personal experiences which permit to overcame the barrier of drug use occasionally. The analysis of how the system reacts to perturbations is very important to understand its key elements and it provides strategies for effective policy making. The present model represents the first step of a realistic description of this phenomenon and can be easily generalized in various directions.

  12. On infrastructure network design with agent-based modelling

    OpenAIRE

    Chappin, E.J.L.; Heijnen, P.W.

    2014-01-01

    We have developed an agent-based model to optimize green-field network design in an industrial area. We aim to capture some of the deep uncertainties surrounding infrastructure design by modelling it developing specific ant colony optimizations. Hence, we propose a variety of extensions to our existing work, first ideas on how to realize them and three cases to explicate our ideas. One case is the design of a CO2 pipeline network in Rotterdam industrial area. First simulation results have sho...

  13. Agent-based multi-optional model of innovations diffusion

    CERN Document Server

    Laciana, Carlos E

    2013-01-01

    We propose a formalism that allows the study of the process of diffusion of several products competing in a common market. It is based on the generalization of the statistics Ising model (Potts model). For the implementation, agent based modeling is used, applied to a problem of three options; to adopt a product A, a product B, or non-adoption. A launching strategy is analyzed for one of the two products, which delays its launching with the objective of competing with improvements. The proportion reached by one and another product is calculated at market saturation. The simulations are produced varying the social network topology, the uncertainty in the decision, and the population's homogeneity.

  14. Using Agent Based Modeling (ABM) to Develop Cultural Interaction Simulations

    Science.gov (United States)

    Drucker, Nick; Jones, Phillip N.

    2012-01-01

    Today, most cultural training is based on or built around "cultural engagements" or discrete interactions between the individual learner and one or more cultural "others". Often, success in the engagement is the end or the objective. In reality, these interactions usually involve secondary and tertiary effects with potentially wide ranging consequences. The concern is that learning culture within a strict engagement context might lead to "checklist" cultural thinking that will not empower learners to understand the full consequence of their actions. We propose the use of agent based modeling (ABM) to collect, store, and, simulating the effects of social networks, promulgate engagement effects over time, distance, and consequence. The ABM development allows for rapid modification to re-create any number of population types, extending the applicability of the model to any requirement for social modeling.

  15. Complexity and agent-based modelling in urban research

    DEFF Research Database (Denmark)

    Fertner, Christian

    influence on the bigger system. Traditional scientific methods or theories often tried to simplify, not accounting complex relations of actors and decision-making. The introduction of computers in simulation made new approaches in modelling, as for example agent-based modelling (ABM), possible, dealing...... with issues of complexity. Also in urban research, computer simulation is becoming popular for more and more issues, aiming at a new understanding of urban systems. The essay is based on some recent articles as well as some relevant websites. Due to the use of ABM in many scientific fields and the relevance......Urbanisation processes are results of a broad variety of actors or actor groups and their behaviour and decisions based on different experiences, knowledge, resources, values etc. The decisions done are often on a micro/individual level but resulting in macro/collective behaviour. In urban research...

  16. Agent-based modelling of consumer energy choices

    Science.gov (United States)

    Rai, Varun; Henry, Adam Douglas

    2016-06-01

    Strategies to mitigate global climate change should be grounded in a rigorous understanding of energy systems, particularly the factors that drive energy demand. Agent-based modelling (ABM) is a powerful tool for representing the complexities of energy demand, such as social interactions and spatial constraints. Unlike other approaches for modelling energy demand, ABM is not limited to studying perfectly rational agents or to abstracting micro details into system-level equations. Instead, ABM provides the ability to represent behaviours of energy consumers -- such as individual households -- using a range of theories, and to examine how the interaction of heterogeneous agents at the micro-level produces macro outcomes of importance to the global climate, such as the adoption of low-carbon behaviours and technologies over space and time. We provide an overview of ABM work in the area of consumer energy choices, with a focus on identifying specific ways in which ABM can improve understanding of both fundamental scientific and applied aspects of the demand side of energy to aid the design of better policies and programmes. Future research needs for improving the practice of ABM to better understand energy demand are also discussed.

  17. Multi-agent Based Hierarchy Simulation Models of Carrier-based Aircraft Catapult Launch

    Institute of Scientific and Technical Information of China (English)

    Wang Weijun; Qu Xiangju; Guo Linliang

    2008-01-01

    With the aid of multi-agent based modeling approach to complex systems,the hierarchy simulation models of carrier-based aircraft catapult launch are developed.Ocean,carrier,aircraft,and atmosphere are treated as aggregation agents,the detailed components like catapult,landing gears,and disturbances are considered as meta-agents,which belong to their aggregation agent.Thus,the model with two layers is formed i.e.the aggregation agent layer and the meta-agent layer.The information communication among all agents is described.The meta-agents within one aggregation agent communicate with each other directly by information sharing,but the meta-agents,which belong to different aggregation agents exchange their information through the aggregation layer fast,and then perceive it from the sharing environment,that is the aggregation agent.Thus,not only the hierarchy model is built,but also the environment perceived by each agent is specified.Meanwhile,the problem of balancing the independency of agent and the resource consumption brought by real-time communication within multi-agent system (MAS) is resolved.Each agent involved in carrier-based aircraft catapult launch is depicted,with considering the interaction within disturbed atmospheric environment and multiple motion bodies including carrier,aircraft,and landing gears.The models of reactive agents among them are derived based on tensors,and the perceived messages and inner frameworks of each agent are characterized.Finally,some results of a simulation instance are given.The simulation and modeling of dynamic system based on multi-agent system is of benefit to express physical concepts and logical hierarchy clearly and precisely.The system model can easily draw in kinds of other agents to achieve a precise simulation of more complex system.This modeling technique makes the complex integral dynamic equations of multibodies decompose into parallel operations of single agent,and it is convenient to expand,maintain,and reuse

  18. A Multi Agent Based Model for Airport Service Planning

    Directory of Open Access Journals (Sweden)

    W.H. Ip

    2010-09-01

    Full Text Available Aviation industry is highly dynamic and demanding in nature that time and safety are the two most important factors while one of the major sources of delay is aircraft on ground because of it complexity, a lot of machinery like vehicles are involved and lots of communication are involved. As one of the aircraft ground services providers in Hong Kong International Airport, China Aircraft Services Limited (CASL aims to increase competitiveness by better its service provided while minimizing cost is also needed. One of the ways is to optimize the number of maintenance vehicles allocated in order to minimize chance of delay and also operating costs. In the paper, an agent-based model is proposed for support decision making in vehicle allocation. The overview of the aircrafts ground services procedures is firstly mentioned with different optimization methods suggested by researchers. Then, the agent-based approach is introduced and in the latter part of report and a multi-agent system is built and proposed which is decision supportive for CASL in optimizing the maintenance vehicles' allocation. The application provides flexibility for inputting number of different kinds of vehicles, simulation duration and aircraft arrival rate in order to simulation different scenarios which occurs in HKIA.

  19. Multispace Behavioral Model for Face-Based Affective Social Agents

    Directory of Open Access Journals (Sweden)

    DiPaola Steve

    2007-01-01

    Full Text Available This paper describes a behavioral model for affective social agents based on three independent but interacting parameter spaces: knowledge, personality, and mood. These spaces control a lower-level geometry space that provides parameters at the facial feature level. Personality and mood use findings in behavioral psychology to relate the perception of personality types and emotional states to the facial actions and expressions through two-dimensional models for personality and emotion. Knowledge encapsulates the tasks to be performed and the decision-making process using a specially designed XML-based language. While the geometry space provides an MPEG-4 compatible set of parameters for low-level control, the behavioral extensions available through the triple spaces provide flexible means of designing complicated personality types, facial expression, and dynamic interactive scenarios.

  20. Multispace Behavioral Model for Face-Based Affective Social Agents

    Directory of Open Access Journals (Sweden)

    Ali Arya

    2007-03-01

    Full Text Available This paper describes a behavioral model for affective social agents based on three independent but interacting parameter spaces: knowledge, personality, and mood. These spaces control a lower-level geometry space that provides parameters at the facial feature level. Personality and mood use findings in behavioral psychology to relate the perception of personality types and emotional states to the facial actions and expressions through two-dimensional models for personality and emotion. Knowledge encapsulates the tasks to be performed and the decision-making process using a specially designed XML-based language. While the geometry space provides an MPEG-4 compatible set of parameters for low-level control, the behavioral extensions available through the triple spaces provide flexible means of designing complicated personality types, facial expression, and dynamic interactive scenarios.

  1. Using the Agent-Based Modeling in Economic Field

    Directory of Open Access Journals (Sweden)

    Nora Mihail

    2006-12-01

    Full Text Available The last ten years of the XX century has been the witnesses of the apparition of a new scientific field, which is usually defined as the study of “Complex adaptive systems”. This field, generic named Complexity Sciences, shares its subject, the general proprieties of complex systems across traditional disciplinary boundaries, with cybernetics and general systems theory. But the development of Complexity Sciences approaches is determined by the extensive use of Agent-Based-Models (ABM as a research tool and an emphasis on systems, such as markets, populations or ecologies, which are less integrated or “organized” than the ones, such as companies and economies, intensively studied by the traditional disciplines. For ABM, a complex system is a system of individual agents who have the freedom to act in ways that are not always totally predictable, and whose actions are interconnected such that one agent’s actions changes the context (environment for other agents. These are many examples of such complex systems: the stock market, the human body immune system, a business organization, an institution, a work-team, a family etc.

  2. Agent-based Modelling, a new kind of research

    DEFF Research Database (Denmark)

    Held, Fabian P.; Wilkinson, Ian F.; Marks, Robert E.;

    2014-01-01

    We discuss the use of Agent-based Modelling for the development and testing of theories about emergent social phenomena in marketing and the social sciences in general. We address both theoretical aspects about the types of phenomena that are suitably addressed with this approach and practical gu...... development. The main goal of this paper was to make research on complex social systems more accessible and help anticipate and structure the research process. © 2014 Australian and New Zealand Marketing Academy.......We discuss the use of Agent-based Modelling for the development and testing of theories about emergent social phenomena in marketing and the social sciences in general. We address both theoretical aspects about the types of phenomena that are suitably addressed with this approach and practical...... guidelines to help plan and structure the development of a theory about the causes of such a phenomenon in conjunction with a matching ABM. We argue that research about complex social phenomena is still largely fundamental research and therefore an iterative and cyclical development process of both theory...

  3. From Agents to Continuous Change via Aesthetics: Learning Mechanics with Visual Agent-Based Computational Modeling

    Science.gov (United States)

    Sengupta, Pratim; Farris, Amy Voss; Wright, Mason

    2012-01-01

    Novice learners find motion as a continuous process of change challenging to understand. In this paper, we present a pedagogical approach based on agent-based, visual programming to address this issue. Integrating agent-based programming, in particular, Logo programming, with curricular science has been shown to be challenging in previous research…

  4. An Agent Based Modelling Approach for Multi-Stakeholder Analysis of City Logistics Solutions

    OpenAIRE

    Anand, N

    2015-01-01

    This thesis presents a comprehensive framework for multi-stakeholder analysis of city logistics solutions using agent based modeling. The framework describes different stages for the systematic development of an agent based model for the city logistics domain. The framework includes a multi-perspective city logistics ontology and its validation, the development of an agent base model using this ontology, and a validation approach for the agent based model using a participatory simulation game.

  5. Empirical agent-based land market: Integrating adaptive economic behavior in urban land-use models

    NARCIS (Netherlands)

    Filatova, Tatiana

    2015-01-01

    This paper introduces an economic agent-based model of an urban housing market. The RHEA (Risks and Hedonics in Empirical Agent-based land market) model captures natural hazard risks and environmental amenities through hedonic analysis, facilitating empirical agent-based land market modeling. RHEA i

  6. An agent-based model for energy service companies

    International Nuclear Information System (INIS)

    Highlights: • An agent-based model for household energy efficiency upgrades is considered. • Energy service companies provide an alternative to traditional utility providers. • Household self-financing is a limiting factor to widespread efficiency upgrading. • Longer term service contracts can lead to reduced household energy costs. • Future energy price increases enable service providers to retain their customer base. - Abstract: The residential housing sector is a major consumer of energy accounting for approximately one third of carbon emissions in the United Kingdom. Achieving a sustainable, low-carbon infrastructure necessitates a reduced and more efficient use of domestic energy supplies. Energy service companies offer an alternative to traditional providers, which supply a single utility product to satisfy the unconstrained demand of end users, and have been identified as a potentially important actor in sustainable future economies. An agent-based model is developed to examine the potential of energy service companies to contribute to the large scale upgrading of household energy efficiency, which would ultimately lead to a more sustainable and secure energy infrastructure. The migration of households towards energy service companies is described by an attractiveness array, through which potential customers can evaluate the future benefits, in terms of household energy costs, of changing provider. It is shown that self-financing is a limiting factor to the widespread upgrading of residential energy efficiency. Greater reductions in household energy costs could be achieved by committing to longer term contracts, allowing upgrade costs to be distributed over greater time intervals. A steadily increasing cost of future energy usage lends an element of stability to the market, with energy service companies displaying the ability to retain customers on contract expiration. The model highlights how a greater focus on the provision of energy services, as

  7. A Systematic Review of Agent-Based Modelling and Simulation Applications in the Higher Education Domain

    Science.gov (United States)

    Gu, X.; Blackmore, K. L.

    2015-01-01

    This paper presents the results of a systematic review of agent-based modelling and simulation (ABMS) applications in the higher education (HE) domain. Agent-based modelling is a "bottom-up" modelling paradigm in which system-level behaviour (macro) is modelled through the behaviour of individual local-level agent interactions (micro).…

  8. Propagation Modeling of Food Safety Crisis Information Update Based on the Multi-agent System

    OpenAIRE

    Meihong Wu; Jingfei Yang; Zhiling Hong

    2015-01-01

    This study propose a new multi-agent system frame based on epistemic default complex adaptive theory and use the agent based simulation and modeling the information updating process to study food safety crisis information dissemination. Then, we explore interaction effect between each agent in food safety crisis information dissemination at the current environment and mostly reveals how the government agent, food company agent and network media agent influence users confidence in food safety....

  9. Agent-based and individual-based modeling a practical introduction

    CERN Document Server

    Railsback, Steven F

    2011-01-01

    Agent-based modeling is a new technique for understanding how the dynamics of biological, social, and other complex systems arise from the characteristics and behaviors of the agents making up these systems. This innovative textbook gives students and scientists the skills to design, implement, and analyze agent-based models. It starts with the fundamentals of modeling and provides an introduction to NetLogo, an easy-to-use, free, and powerful software platform. Nine chapters then each introduce an important modeling concept and show how to implement it using NetLogo. The book goes on to pres

  10. Disaggregation and Refinement of System Dynamics Models via Agent-based Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nutaro, James J [ORNL; Ozmen, Ozgur [ORNL; Schryver, Jack C [ORNL

    2014-01-01

    System dynamics models are usually used to investigate aggregate level behavior, but these models can be decomposed into agents that have more realistic individual behaviors. Here we develop a simple model of the STEM workforce to illuminate the impacts that arise from the disaggregation and refinement of system dynamics models via agent-based modeling. Particularly, alteration of Poisson assumptions, adding heterogeneity to decision-making processes of agents, and discrete-time formulation are investigated and their impacts are illustrated. The goal is to demonstrate both the promise and danger of agent-based modeling in the context of a relatively simple model and to delineate the importance of modeling decisions that are often overlooked.

  11. Agent-based model of information spread in social networks

    CERN Document Server

    Lande, D V; Berezin, B O

    2016-01-01

    We propose evolution rules of the multiagent network and determine statistical patterns in life cycle of agents - information messages. The main discussed statistical pattern is connected with the number of likes and reposts for a message. This distribution corresponds to Weibull distribution according to modeling results. We examine proposed model using the data from Twitter, an online social networking service.

  12. Modeling of Agile Manufacturing Execution Systems with an Agent-based Approach

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Agile manufacturing execution systems (AMES) are used to help manufacturers optimize shop floor production in an agile way. And the modeling of AMES is the key issue of realizing AMES. This paper presents an agent-based approach to AMES modeling. Firstly, the characteristics of AMES and its requirements on modeling are discussed. Secondly, a comparative analysis of modeling methods is carried out, and AMES modeling using an agent-based approach is put forward. Agent-based modeling method not only inherit ...

  13. Using FLAME Toolkit for Agent-Based Simulation: Case Study Sugarscape Model

    OpenAIRE

    Kiran, Mariam

    2014-01-01

    Social scientists have used agent-based models to understand how individuals interact and behave in various political, ecological and economic scenarios. Agent-based models are ideal for understanding such models involving interacting individuals producing emergent phenomenon. Sugarscape is one of the most famous examples of a social agent-based model which has been used to show how societies grow in the real world. This paper builds on the Sugarscape model, using the Flexible Large scale Age...

  14. E-laboratories : agent-based modeling of electricity markets

    International Nuclear Information System (INIS)

    Electricity markets are complex adaptive systems that operate under a wide range of rules that span a variety of time scales. These rules are imposed both from above by society and below by physics. Many electricity markets are undergoing or are about to undergo a transition from centrally regulated systems to decentralized markets. Furthermore, several electricity markets have recently undergone this transition with extremely unsatisfactory results, most notably in California. These high stakes transitions require the introduction of largely untested regulatory structures. Suitable laboratories that can be used to test regulatory structures before they are applied to real systems are needed. Agent-based models can provide such electronic laboratories or ''e-laboratories.'' To better understand the requirements of an electricity market e-laboratory, a live electricity market simulation was created. This experience helped to shape the development of the Electricity Market Complex Adaptive Systems (EMCAS) model. To explore EMCAS' potential as an e-laboratory, several variations of the live simulation were created. These variations probed the possible effects of changing power plant outages and price setting rules on electricity market prices

  15. Agent-based modeling to simulate the dengue spread

    Science.gov (United States)

    Deng, Chengbin; Tao, Haiyan; Ye, Zhiwei

    2008-10-01

    In this paper, we introduce a novel method ABM in simulating the unique process for the dengue spread. Dengue is an acute infectious disease with a long history of over 200 years. Unlike the diseases that can be transmitted directly from person to person, dengue spreads through a must vector of mosquitoes. There is still no any special effective medicine and vaccine for dengue up till now. The best way to prevent dengue spread is to take precautions beforehand. Thus, it is crucial to detect and study the dynamic process of dengue spread that closely relates to human-environment interactions where Agent-Based Modeling (ABM) effectively works. The model attempts to simulate the dengue spread in a more realistic way in the bottom-up way, and to overcome the limitation of ABM, namely overlooking the influence of geographic and environmental factors. Considering the influence of environment, Aedes aegypti ecology and other epidemiological characteristics of dengue spread, ABM can be regarded as a useful way to simulate the whole process so as to disclose the essence of the evolution of dengue spread.

  16. An Agent-Based Model of Institutional Life-Cycles

    Directory of Open Access Journals (Sweden)

    Manuel Wäckerle

    2014-08-01

    Full Text Available We use an agent-based model to investigate the interdependent dynamics between individual agency and emergent socioeconomic structure, leading to institutional change in a generic way. Our model simulates the emergence and exit of institutional units, understood as generic governed social structures. We show how endogenized trust and exogenously given leader authority influences institutional change, i.e., diversity in institutional life-cycles. It turns out that these governed institutions (destructure in cyclical patterns dependent on the overall evolution of trust in the artificial society, while at the same time, influencing this evolution by supporting social learning. Simulation results indicate three scenarios of institutional life-cycles. Institutions may, (1 build up very fast and freeze the artificial society in a stable but fearful pattern (ordered system; (2 exist only for a short time, leading to a very trusty society (highly fluctuating system; and (3 structure in cyclical patterns over time and support social learning due to cumulative causation of societal trust (complex system.

  17. Agent-based models for higher-order theory of mind

    NARCIS (Netherlands)

    de Weerd, Harmen; Verbrugge, Rineke; Verheij, Bart; Kamiński, Bogumił; Koloch, Grzegorz

    2014-01-01

    Agent-based models are a powerful tool for explaining the emergence of social phenomena in a society. In such models, individual agents typically have little cognitive ability. In this paper, we model agents with the cognitive ability to make use of theory of mind. People use this ability to reason

  18. Crisis response simulation combining discrete-event and agent-based modeling

    NARCIS (Netherlands)

    Gonzalez, R.A.

    2009-01-01

    This paper presents a crisis response simulation model architecture combining a discrete-event simulation (DES) environment for a crisis scenario with an agent-based model of the response organization. In multi-agent systems (MAS) as a computational organization, agents are modeled and implemented s

  19. An Introduction to Agent Based Modelling and Simulation of Social Processes

    OpenAIRE

    Ognjen Skunca; Armano Srbljinovic

    2003-01-01

    The paper provides an introduction to agent-based modelling and simulation of social processes. Reader is introduced to the worldview underlying agent-based models, some basic terminology, basic properties of agent-based models, as well as to what one can and what cannot expect from such models, particularly when they are applied to social-scientific investigation. Special attention is given to the issues of validation.

  20. Agent-Based Modelling: Tools for Linking NetLogo and r

    OpenAIRE

    Jan C Thiele; Winfried Kurth; Volker Grimm

    2012-01-01

    A seamless integration of software platforms for implementing agent-based models and for analysing their output would facilitate comprehensive model analyses and thereby make agent-based modelling more useful. Here we report on recently developed tools for linking two widely used software platforms: NetLogo for implementing agent-based models, and R for the statistical analysis and design of experiments. Embedding R into NetLogo allows the use of advanced statistical analyses, specific statis...

  1. A Transport Model of Mobile Agent Based on Secure Hybrid Encryption

    Institute of Scientific and Technical Information of China (English)

    SUNZhixin; CHENZhixian; WANGRuchuan

    2005-01-01

    The solution of security problems of mobile agents is a key issue, which will decide whether mobile agents can be widely used. The paper analyzes main security problems, which currently are confronted with mobile agent systems and existing protection solutions. And then the paper presents a Security Transport model of mobile agents based on a hybrid encryption algorithm (TMSHE).Meanwhile, it expatiates on implementation of the algorithm. The algorithm of TMSHE model mainly consists of two parts, i.e., employing a hybrid encryption algorithm to encrypt mobile agents and using Transport layer security (TLS) to encrypt communication channel. Mobile agents by hybrid encryption move through communication channels, which are encrypted by TLS. The simulation results indicate that the model can protect mobile agents' security effectively, and consequently the security and steadiness of the whole mobile agent system are also improved. The model has succeeded in getting application in a prototypesystem- Intrusion detection system based on mobile agents.

  2. Multi-level agent-based modeling with the Influence Reaction principle

    OpenAIRE

    Morvan, Gildas; Jolly, Daniel

    2012-01-01

    This paper deals with the specification and the implementation of multi-level agent-based models, using a formal model, IRM4MLS (an Influence Reaction Model for Multi-Level Simulation), based on the Influence Reaction principle. Proposed examples illustrate forms of top-down control in (multi-level) multi-agent based-simulations.

  3. Signal amplification in an agent-based herding model

    CERN Document Server

    Carro, Adrián; Miguel, Maxi San

    2013-01-01

    A growing part of the behavioral finance literature has addressed some of the stylized facts of financial time series as macroscopic patterns emerging from herding interactions among groups of agents with heterogeneous trading strategies and a limited rationality. We extend a stochastic herding formalism introduced for the modeling of decision making among financial agents, in order to take also into account an external influence. In particular, we study the amplification of an external signal imposed upon the agents by a mechanism of resonance. This signal can be interpreted as an advertising or a public perception in favor or against one of the two possible trading behaviors, thus periodically breaking the symmetry of the system and acting as a continuously varying exogenous shock. The conditions for the ensemble of agents to more accurately follow the periodicity of the signal are studied, finding a maximum in the response of the system for a given range of values of both the noise and the frequency of the...

  4. Opinion transmission in organizations: an agent-based modeling approach

    OpenAIRE

    Rouchier, Juliette; Tubaro, Paola; Emery, Cécile

    2014-01-01

    This paper builds a theoretical framework to detect the conditions under which social influence enables persistence of a shared opinion among members of an organization over time, despite membership turnover. It develops agent-based simulations of opinion evolution in an advice network, whereby opinion is defined in the broad sense of shared understandings on a matter that is relevant for an organization’s activities, and on which members have some degree of discretion. We combine a micro-lev...

  5. Pattern-Oriented Modeling of Agent-Based Complex Systems: Lessons from Ecology

    OpenAIRE

    Grimm, Volker; Revilla, Eloy; Berger, Uta; Jeltsch, Florian; Mooij, Wolf M.; Railsback, Steven F.; Thulke, Hans-Hermann; Weiner, Jacob; Wiegand, Thorsten; Donald L DeAngelis

    2005-01-01

    Agent-based complex systems are dynamic networks of many interacting agents; examples include ecosystems, financial markets, and cities. The search for general principles underlying the internal organization of such systems often uses bottom-up simulation models such as cellular automata and agent-based models. No general framework for designing, testing, and analyzing bottom-up models has yet been established, but recent advances in ecological modeling have come together in a genera...

  6. Multi-agent based modeling for electric vehicle integration in a distribution network operation

    DEFF Research Database (Denmark)

    Hu, Junjie; Morais, Hugo; Lind, Morten;

    2016-01-01

    The purpose of this paper is to present a multi-agent based modeling technology for simulating and operating a hierarchical energy management of a power distribution system with focus on EVs integration. The proposed multi-agent system consists of four types of agents: i) Distribution system...... of the proposed system, a multi-agent simulation platform is developed based on the co-simulation environment of JACK, Matlab and GAMS. The aim of the multi-agent system is to simulate the collaborative (all agents contribute to achieve an optimized global performance) but also competitive environment (each agent...... operator (DSO) technical agent and ii) DSO market agents that both belong to the top layer of the hierarchy and their roles are to manage the distribution network by avoiding grid congestions and using congestion prices to coordinate the energy scheduled; iii) Electric vehicle virtual power plant agents...

  7. Agent-Based Modeling of Consumer Decision making Process Based on Power Distance and Personality

    NARCIS (Netherlands)

    Roozmand, O.; Ghasem-Aghaee, N.; Hofstede, G.J.; Nematbakhsh, M.A.; Baraani, A.; Verwaart, T.

    2011-01-01

    Simulating consumer decision making processes involves different disciplines such as: sociology, social psychology, marketing, and computer science. In this paper, we propose an agent-based conceptual and computational model of consumer decision-making based on culture, personality and human needs.

  8. Macroeconomic Fluctuations and Propagation Mechanisms: An Agent-Based Simulation Model

    OpenAIRE

    Sella Lisa

    2009-01-01

    This paper proposes an agent-based simulation model exploring aggregate business fluctuations in an artificial market economy. It is inspired by the C++ agent-based simulation model in Howitt (2006), and proposes a modified NetLogo model, which provides new procedures and parameters aiming at analyzing the endogenous dynamics of market adjustment processes

  9. Mapping Cyclists’ Experiences and Agent-Based Modelling of Their Wayfinding Behaviour

    DEFF Research Database (Denmark)

    Snizek, Bernhard

    with spatial agents and model calibration data creation This paper has two objectives, which are to develop and present a method for simulating single GPS-based trajectories by applying an agent-based model and to acquire parameter values for CopenhagenABM, an agent-based model of cyclists’ behaviour. The core......This dissertation is about modelling cycling transport behaviour. It is partly about urban experiences seen by the cyclist and about modelling, more specifically the agent-based modelling of cyclists' wayfinding behaviour. The dissertation consists of three papers. The first deals...... into consideration. The resulting routes' overlap with routes taken from the real world was calculated and used as a qualifier for the capacity of the model to explain the real world phenomenon. The analyses and the conclusions from these model results are discussed at the end of the paper. CopenhagenABM: An Agent-based...

  10. Agent-based simulation of building evacuation using a grid graph-based model

    International Nuclear Information System (INIS)

    Shifting from macroscope models to microscope models, the agent-based approach has been widely used to model crowd evacuation as more attentions are paid on individualized behaviour. Since indoor evacuation behaviour is closely related to spatial features of the building, effective representation of indoor space is essential for the simulation of building evacuation. The traditional cell-based representation has limitations in reflecting spatial structure and is not suitable for topology analysis. Aiming at incorporating powerful topology analysis functions of GIS to facilitate agent-based simulation of building evacuation, we used a grid graph-based model in this study to represent the indoor space. Such model allows us to establish an evacuation network at a micro level. Potential escape routes from each node thus could be analysed through GIS functions of network analysis considering both the spatial structure and route capacity. This would better support agent-based modelling of evacuees' behaviour including route choice and local movements. As a case study, we conducted a simulation of emergency evacuation from the second floor of an official building using Agent Analyst as the simulation platform. The results demonstrate the feasibility of the proposed method, as well as the potential of GIS in visualizing and analysing simulation results

  11. Supply Chain Management System Model of Virtual Enterprises Based on Multi-Agent

    Institute of Scientific and Technical Information of China (English)

    LI Zhen; ZHANG Pei-pei

    2008-01-01

    Based on the analysis of a virtual enterprise and the development of supply chain management, their integration is proposed. Then, the difference between multi-agent system modeling method and the traditional modeling method is analyzed, and a method based on Java agent framework for multi-agent systems(JAFMAS) is proposed. By using this method the virtual enterprise's supply chain management system model is established.

  12. Between Complexity and Parsimony: Can Agent-Based Modelling Resolve the Trade-off

    DEFF Research Database (Denmark)

    Nielsen, Helle Ørsted; Malawska, Anna Katarzyna

    2013-01-01

    to BR- based policy studies would be to couple research on bounded ra-tionality with agent-based modeling. Agent-based models (ABMs) are computational models for simulating the behavior and interactions of any number of decision makers in a dynamic system. Agent-based models are better suited than...... with regards to behavioral rules. Bounded rationality research therefore could ensure realistic modeling while the ABM approach enhances the predictive value of behavioral modeling. This paper thus discusses the promise and limitations of using agent-based models to advance the use of the bounded rationality......While Herbert Simon espoused development of general models of behavior, he also strongly advo-cated that these models be based on realistic assumptions about humans and therefore reflect the complexity of human cognition and social systems (Simon 1997). Hence, the model of bounded rationality...

  13. Pattern-oriented modeling of agent-based complex systems: lessons from ecology

    NARCIS (Netherlands)

    Grimm, V.; Revilla, E.; Berger, U.; Jeltsch, F.; Mooij, W.M.; Railsback, S.F.; Thulke, H-H.; Weiner, J.; Wiegand, T.; DeAngelis, D.L.

    2005-01-01

    Agent-based complex systems are dynamic networks of many interacting agents; examples include ecosystems, financial markets, and cities. The search for general principles underlying the internal organization of such systems often uses bottom-up simulation models such as cellular automata and agent-b

  14. Stylized facts from a threshold-based heterogeneous agent model

    CERN Document Server

    Cross, R; Lamba, H; Seaman, T

    2006-01-01

    A class of heterogeneous agent models is investigated where investors switch trading position whenever their motivation to do so exceeds some critical threshold. These motivations can be psychological in nature or reflect behaviour suggested by the efficient market hypothesis (EMH). By introducing different propensities into a baseline model that displays EMH behaviour, one can attempt to isolate their effects upon the market dynamics. The simulation results indicate that the introduction of a herding propensity results in excess kurtosis and power-law decay consistent with those observed in actual return distributions, but not in significant long-term volatility correlations. Possible alternatives for introducing such long-term volatility correlations are then identified and discussed.

  15. Stylized facts from a threshold-based heterogeneous agent model

    Science.gov (United States)

    Cross, R.; Grinfeld, M.; Lamba, H.; Seaman, T.

    2007-05-01

    A class of heterogeneous agent models is investigated where investors switch trading position whenever their motivation to do so exceeds some critical threshold. These motivations can be psychological in nature or reflect behaviour suggested by the efficient market hypothesis (EMH). By introducing different propensities into a baseline model that displays EMH behaviour, one can attempt to isolate their effects upon the market dynamics. The simulation results indicate that the introduction of a herding propensity results in excess kurtosis and power-law decay consistent with those observed in actual return distributions, but not in significant long-term volatility correlations. Possible alternatives for introducing such long-term volatility correlations are then identified and discussed.

  16. Demeter, persephone, and the search for emergence in agent-based models.

    Energy Technology Data Exchange (ETDEWEB)

    North, M. J.; Howe, T. R.; Collier, N. T.; Vos, J. R.; Decision and Information Sciences; Univ. of Chicago; PantaRei Corp.; Univ. of Illinois

    2006-01-01

    In Greek mythology, the earth goddess Demeter was unable to find her daughter Persephone after Persephone was abducted by Hades, the god of the underworld. Demeter is said to have embarked on a long and frustrating, but ultimately successful, search to find her daughter. Unfortunately, long and frustrating searches are not confined to Greek mythology. In modern times, agent-based modelers often face similar troubles when searching for agents that are to be to be connected to one another and when seeking appropriate target agents while defining agent behaviors. The result is a 'search for emergence' in that many emergent or potentially emergent behaviors in agent-based models of complex adaptive systems either implicitly or explicitly require search functions. This paper considers a new nested querying approach to simplifying such agent-based modeling and multi-agent simulation search problems.

  17. Excellent approach to modeling urban expansion by fuzzy cellular automata: agent base model

    Science.gov (United States)

    Khajavigodellou, Yousef; Alesheikh, Ali A.; Mohammed, Abdulrazak A. S.; Chapi, Kamran

    2014-09-01

    Recently, the interaction between humans and their environment is the one of important challenges in the world. Landuse/ cover change (LUCC) is a complex process that includes actors and factors at different social and spatial levels. The complexity and dynamics of urban systems make the applicable practice of urban modeling very difficult. With the increased computational power and the greater availability of spatial data, micro-simulation such as the agent based and cellular automata simulation methods, has been developed by geographers, planners, and scholars, and it has shown great potential for representing and simulating the complexity of the dynamic processes involved in urban growth and land use change. This paper presents Fuzzy Cellular Automata in Geospatial Information System and remote Sensing to simulated and predicted urban expansion pattern. These FCA-based dynamic spatial urban models provide an improved ability to forecast and assess future urban growth and to create planning scenarios, allowing us to explore the potential impacts of simulations that correspond to urban planning and management policies. A fuzzy inference guided cellular automata approach. Semantic or linguistic knowledge on Land use change is expressed as fuzzy rules, based on which fuzzy inference is applied to determine the urban development potential for each pixel. The model integrates an ABM (agent-based model) and FCA (Fuzzy Cellular Automata) to investigate a complex decision-making process and future urban dynamic processes. Based on this model rapid development and green land protection under the influences of the behaviors and decision modes of regional authority agents, real estate developer agents, resident agents and non- resident agents and their interactions have been applied to predict the future development patterns of the Erbil metropolitan region.

  18. An Agent Based Modelling Approach for Multi-Stakeholder Analysis of City Logistics Solutions

    NARCIS (Netherlands)

    Anand, N.

    2015-01-01

    This thesis presents a comprehensive framework for multi-stakeholder analysis of city logistics solutions using agent based modeling. The framework describes different stages for the systematic development of an agent based model for the city logistics domain. The framework includes a multi-perspect

  19. Simulating tissue mechanics with agent-based models: concepts, perspectives and some novel results

    Science.gov (United States)

    Van Liedekerke, P.; Palm, M. M.; Jagiella, N.; Drasdo, D.

    2015-12-01

    In this paper we present an overview of agent-based models that are used to simulate mechanical and physiological phenomena in cells and tissues, and we discuss underlying concepts, limitations, and future perspectives of these models. As the interest in cell and tissue mechanics increase, agent-based models are becoming more common the modeling community. We overview the physical aspects, complexity, shortcomings, and capabilities of the major agent-based model categories: lattice-based models (cellular automata, lattice gas cellular automata, cellular Potts models), off-lattice models (center-based models, deformable cell models, vertex models), and hybrid discrete-continuum models. In this way, we hope to assist future researchers in choosing a model for the phenomenon they want to model and understand. The article also contains some novel results.

  20. The "Wedding-Ring": An agent-based marriage model based on social interaction

    Directory of Open Access Journals (Sweden)

    Alexia Prskawetz

    2007-08-01

    Full Text Available In this paper we develop an agent-based marriage model based on social interaction. We build an population of interacting agents whose chances of marrying depend on the availability of partners, and whose willingness to marry depends on the share of relevant others in their social network who are already married. We then let the typical aggregate age pattern of marriage emerge from the bottom-up. The results of our simulation show that micro-level hypotheses founded on existing theory and evidence on social interaction can reproduce age-at-marriage patterns with both realistic shape and realistic micro-level dynamics.

  1. Using Hybrid Agent-Based Systems to Model Spatially-Influenced Retail Markets

    OpenAIRE

    Alison Heppenstall; Andrew Evans; Mark Birkin

    2006-01-01

    One emerging area of agent-based modelling is retail markets; however, there are problems with modelling such systems. The vast size of such markets makes individual-level modelling, for example of customers, difficult and this is particularly true where the markets are spatially complex. There is an emerging recognition that the power of agent-based systems is enhanced when integrated with other AI-based and conventional approaches. The resulting hybrid models are powerful tools that combine...

  2. Brief introductory guide to agent-based modeling and an illustration from urban health research.

    Science.gov (United States)

    Auchincloss, Amy H; Garcia, Leandro Martin Totaro

    2015-11-01

    There is growing interest among urban health researchers in addressing complex problems using conceptual and computation models from the field of complex systems. Agent-based modeling (ABM) is one computational modeling tool that has received a lot of interest. However, many researchers remain unfamiliar with developing and carrying out an ABM, hindering the understanding and application of it. This paper first presents a brief introductory guide to carrying out a simple agent-based model. Then, the method is illustrated by discussing a previously developed agent-based model, which explored inequalities in diet in the context of urban residential segregation. PMID:26648364

  3. Brief introductory guide to agent-based modeling and an illustration from urban health research

    Directory of Open Access Journals (Sweden)

    Amy H. Auchincloss

    2015-11-01

    Full Text Available Abstract There is growing interest among urban health researchers in addressing complex problems using conceptual and computation models from the field of complex systems. Agent-based modeling (ABM is one computational modeling tool that has received a lot of interest. However, many researchers remain unfamiliar with developing and carrying out an ABM, hindering the understanding and application of it. This paper first presents a brief introductory guide to carrying out a simple agent-based model. Then, the method is illustrated by discussing a previously developed agent-based model, which explored inequalities in diet in the context of urban residential segregation.

  4. An artificial economy based on reinforcement learning and agent based modeling

    OpenAIRE

    Fernando Lozano; Jaime Lozano; Mario García

    2007-01-01

    In this paper we employ techniques from artificial intelligence such as reinforcement learning and agent based modeling as building blocks of a computational model for an economy based on convention. First we model the interaction among firms in the private sector. These firms behave in an information environment based on conventions meaning that a firm is likely to behave as it neighbors if it observes that their actions lead to a good pay-off. On the other hand, we propose the use of reinfo...

  5. Practicality of Agent-Based Modeling of Civil Violence: an Assessment

    CERN Document Server

    Thron, Christopher

    2015-01-01

    Joshua Epstein (2002) proposed a simple agent-based model to describe the formation and evolution of spontaneous civil violence (such as riots or violent demonstrations). In this paper we study the practical applicability of Epstein's model.

  6. Model reduction for agent-based social simulation: Coarse-graining a civil violence model

    Science.gov (United States)

    Zou, Yu; Fonoberov, Vladimir A.; Fonoberova, Maria; Mezic, Igor; Kevrekidis, Ioannis G.

    2012-06-01

    Agent-based modeling (ABM) constitutes a powerful computational tool for the exploration of phenomena involving emergent dynamic behavior in the social sciences. This paper demonstrates a computer-assisted approach that bridges the significant gap between the single-agent microscopic level and the macroscopic (coarse-grained population) level, where fundamental questions must be rationally answered and policies guiding the emergent dynamics devised. Our approach will be illustrated through an agent-based model of civil violence. This spatiotemporally varying ABM incorporates interactions between a heterogeneous population of citizens [active (insurgent), inactive, or jailed] and a population of police officers. Detailed simulations exhibit an equilibrium punctuated by periods of social upheavals. We show how to effectively reduce the agent-based dynamics to a stochastic model with only two coarse-grained degrees of freedom: the number of jailed citizens and the number of active ones. The coarse-grained model captures the ABM dynamics while drastically reducing the computation time (by a factor of approximately 20).

  7. An Agent-Based Model of Collective Emotions in Online Communities

    CERN Document Server

    Schweitzer, Frank

    2010-01-01

    We develop a agent-based framework to model the emergence of collective emotions, which is applied to online communities. Agents individual emotions are described by their valence and arousal. Using the concept of Brownian agents, these variables change according to a stochastic dynamics, which also considers the feedback from online communication. Agents generate emotional information, which is stored and distributed in a field modeling the online medium. This field affects the emotional states of agents in a non-linear manner. We derive conditions for the emergence of collective emotions, observable in a bimodal valence distribution. Dependent on a saturated or a superlinear feedback between the information field and the agent's arousal, we further identify scenarios where collective emotions only appear once or in a repeated manner. The analytical results are illustrated by agent-based computer simulations. Our framework provides testable hypotheses about the emergence of collective emotions, which can be ...

  8. Agent-based land-use models: a review of applications

    OpenAIRE

    Matthews, RB; Gilbert, NG; Roach, A.; Polhill, JG; Gotts, NM

    2007-01-01

    Agent-based modelling is an approach that has been receiving attention by the land use modelling community in recent years, mainly because it offers a way of incorporating the influence of human decision-making on land use in a mechanistic, formal, and spatially explicit way, taking into account social interaction, adaptation, and decision-making at different levels. Specific advantages of agent-based models include their ability to model individual decision-making entities and their interact...

  9. Predictability of Shanghai Stock Market by Agent-based Mix-game Model

    CERN Document Server

    Gou, C

    2005-01-01

    This paper reports the effort of using agent-based mix-game model to predict financial time series. It introduces the prediction methodology by means of mix-game model and gives an example of its application to forecasting Shanghai Index. The results show that this prediction methodology is effective and agent-based mix-game model is a potential good model to predict time series of financial markets.

  10. Lapse of time effects on tax evasion in an agent-based econophysics model

    Science.gov (United States)

    Seibold, Götz; Pickhardt, Michael

    2013-05-01

    We investigate an inhomogeneous Ising model in the context of tax evasion dynamics where different types of agents are parameterized via local temperatures and magnetic fields. In particular, we analyze the impact of lapse of time effects (i.e. backauditing) and endogenously determined penalty rates on tax compliance. Both features contribute to a microfoundation of agent-based econophysics models of tax evasion.

  11. On the role of backauditing for tax evasion in an agent-based Econophysics model

    CERN Document Server

    Seibold, G

    2012-01-01

    We investigate an inhomogeneous Ising model in the context of tax evasion dynamics where different types of agents are parametrized via local temperatures and magnetic fields. In particular, we analyse the impact of backauditing and endogenously determined penalty rates on tax compliance. Both features contribute to a microfoundation of agent-based econophysics models of tax evasion.

  12. Agent-Based Model for Pedestrians’ Evacuation after a Blast Integrated with a Human Behavior Model

    OpenAIRE

    PLUCHINO Salvatore; TRIBOLATO Chiara; CAVERZAN ALESSIO; MC QUILLAN Alexandro; Cimellaro, Gian Paolo; MAHIN Stephen A.

    2015-01-01

    Agent-based modeling (ABM) is a powerful tool for model complex and heterogeneous systems as pedestrian evacuation after extreme events. Several studies on Emergency Management exist in literature, but the majority of them do not consider how human behavior impacts the evacuation plan. Indeed, these can change drastically a critical scenario because are driven by emotions, knowledge and perception which are unpredictable. The aim of this study is to develop an ABM of an evacuation scenario du...

  13. Agent-Based Modeling and Genetic Algorithm Simulation for the Climate Game Problem

    OpenAIRE

    Zheng Wang; Jingling Zhang

    2012-01-01

    The cooperative game of global temperature lacks automaticity and emotional jamming. To solve this issue, an agent-based modelling method is developed based on Milinski’s noncooperative game experiments. In addition, genetic algorithm is used to improve the investment strategy of each agent. Simulations are carried out by designing different coding schemes, mutation schemes, and fitness functions. It is demonstrated that the method can achieve maximum benefits under the premise of the agent n...

  14. Minority persistence in agent based model using information and emotional arousal as control variables

    Science.gov (United States)

    Sobkowicz, Pawel

    2013-07-01

    We present detailed analysis of the behavior of an agent based model of opinion formation, using a discrete variant of cusp catastrophe behavior of single agents. The agent opinion about a particular issue is determined by its information about the issue and its emotional arousal. It is possible that for agitated agents the same information would lead to different opinions. This results in a nontrivial individual opinion dynamics. The agents communicate via messages, which allows direct application of the model to ICT based communities. We study the dependence of the composition of an agent society on the range of interactions and the rate of emotional arousal. Despite the minimal number of adjustable parameters, the model reproduces several phenomena observed in real societies, for example nearly perfectly balanced results of some highly contested elections or the fact that minorities seldom perceive themselves to be a minority.

  15. New E-Commerce Model Based on Multi-Agent Automated Negotiation

    Institute of Scientific and Technical Information of China (English)

    向传杰; 贾云得

    2003-01-01

    A new multi-agent automated negotiation model is developed and evaluated, in which two competitive agents, such as the buyer and seller, have firm deadlines and incomplete information about each other. The negotiation is multi-dimensional in different cases. The model is discussed in 6 kinds of cases with different price strategies, warrantee strategies and time strategies. The model improves the model of Wooldridge and that of Sycara to a certain extent. In all possible situations, the optimal negotiation strategy is analyzed and presented, and an e-commerce model based on multi-agent automated negotiation model is also illustrated for the e-commerce application in the future.

  16. Empirically Grounded Agent-Based Models of Innovation Diffusion: A Critical Review

    CERN Document Server

    Zhang, Haifeng

    2016-01-01

    Innovation diffusion has been studied extensively in a variety of disciplines, including sociology, economics, marketing, ecology, and computer science. Traditional literature on innovation diffusion has been dominated by models of aggregate behavior and trends. However, the agent-based modeling (ABM) paradigm is gaining popularity as it captures agent heterogeneity and enables fine-grained modeling of interactions mediated by social and geographic networks. While most ABM work on innovation diffusion is theoretical, empirically grounded models are increasingly important, particularly in guiding policy decisions. We present a critical review of empirically grounded agent-based models of innovation diffusion, developing a categorization of this research based on types of agent models as well as applications. By connecting the modeling methodologies in the fields of information and innovation diffusion, we suggest that the maximum likelihood estimation framework widely used in the former is a promising paradigm...

  17. Using the Agent-Based Modeling in Economic Field

    Directory of Open Access Journals (Sweden)

    Nora Mihail

    2006-10-01

    For ABM, a complex system is a system of individual agents who have the freedom to act in ways that are not always totally predictable, and whose actions are interconnected such that one agent’s actions changes the context (environment for other agents. These are many examples of such complex systems: the stock market, the human body immune system, a business organization, an institution, a work-team, a family etc.

  18. A Dynamic Cordon Pricing Scheme combining a Macroscopic and an Agent-based traffic Models

    OpenAIRE

    Zheng, Nan; Waraich, Rashid A.; Axhausen, Kay W.; Geroliminis, Nikolaos

    2012-01-01

    Pricing is considered an effective management policy to reduce traffic congestion in transportation networks. In this paper we combine a macroscopic model of traffic congestion in urban networks with an agent-based simulator to study congestion pricing schemes. The macroscopic model, which has been tested with real data in previous studies, represents an accurate and robust approach to model the dynamics of congestion. The agent-based simulator can reproduce the complexity of travel behavior ...

  19. Comparing Stochastic Differential Equations and Agent-Based Modelling and Simulation for Early-Stage Cancer

    OpenAIRE

    Figueredo, Grazziela P.; Peer-Olaf Siebers; Owen, Markus R.; Jenna Reps; Uwe Aickelin

    2014-01-01

    There is great potential to be explored regarding the use of agent-based modelling and simulation as an alternative paradigm to investigate early-stage cancer interactions with the immune system. It does not suffer from some limitations of ordinary differential equation models, such as the lack of stochasticity, representation of individual behaviours rather than aggregates and individual memory. In this paper we investigate the potential contribution of agent-based modelling and simulation w...

  20. Agent-based model for rural-urban migration: A dynamic consideration

    Science.gov (United States)

    Cai, Ning; Ma, Hai-Ying; Khan, M. Junaid

    2015-10-01

    This paper develops a dynamic agent-based model for rural-urban migration, based on the previous relevant works. The model conforms to the typical dynamic linear multi-agent systems model concerned extensively in systems science, in which the communication network is formulated as a digraph. Simulations reveal that consensus of certain variable could be harmful to the overall stability and should be avoided.

  1. Exploring the World of Agent-Based Simulations: Simple Models, Complex Analyses

    OpenAIRE

    Sanchez, Susan M.; Lucas, Thomas W.

    2002-01-01

    Proceedings of the 2002 Winter Simulation Conference E. Yücesan, C.-H. Chen, J. L. Snowdon, and J. M. Charnes, eds. Agent-based simulations are models where multiple entities sense and stochastically respond to conditions in their local environments, mimicking complex large-scale system behavior. We provide an overview of some important issues in the modeling and analysis of agent-based systems. Examples are drawn from a range of fields: biological modeling, sociologic...

  2. Getting away from numbers: Using qualitative observation for agent-based modeling

    OpenAIRE

    Yang, L; Gilbert, N.

    2008-01-01

    Although in many social sciences there is a radical division between studies based on quantitative (e.g. statistical) and qualitative (e.g. ethnographic) methodologies and their associated epistemological commitments, agent-based simulation fits into neither camp, and should be capable of modelling both quantitative and qualitative data. Nevertheless, most agent-based models (ABMs) are founded on quantitative data. This paper explores some of the methodological and practical problems involved...

  3. Consentaneous agent-based and stochastic model of the financial markets.

    Directory of Open Access Journals (Sweden)

    Vygintas Gontis

    Full Text Available We are looking for the agent-based treatment of the financial markets considering necessity to build bridges between microscopic, agent based, and macroscopic, phenomenological modeling. The acknowledgment that agent-based modeling framework, which may provide qualitative and quantitative understanding of the financial markets, is very ambiguous emphasizes the exceptional value of well defined analytically tractable agent systems. Herding as one of the behavior peculiarities considered in the behavioral finance is the main property of the agent interactions we deal with in this contribution. Looking for the consentaneous agent-based and macroscopic approach we combine two origins of the noise: exogenous one, related to the information flow, and endogenous one, arising form the complex stochastic dynamics of agents. As a result we propose a three state agent-based herding model of the financial markets. From this agent-based model we derive a set of stochastic differential equations, which describes underlying macroscopic dynamics of agent population and log price in the financial markets. The obtained solution is then subjected to the exogenous noise, which shapes instantaneous return fluctuations. We test both Gaussian and q-Gaussian noise as a source of the short term fluctuations. The resulting model of the return in the financial markets with the same set of parameters reproduces empirical probability and spectral densities of absolute return observed in New York, Warsaw and NASDAQ OMX Vilnius Stock Exchanges. Our result confirms the prevalent idea in behavioral finance that herding interactions may be dominant over agent rationality and contribute towards bubble formation.

  4. Innovation, demand, and finance in an agent based-stock flow consistent model

    OpenAIRE

    Caiani, Alessandro; Caverzas, Eugenio; Godin, Antoine,; Riccetti, Luca; Russo, Alberto; Gallegati, Mauro; Kinsella, Stephen; Stiglitz, Joseph

    2014-01-01

    We present an agent based stock flow consistent macroeconomic model with heterogeneous agents interacting through a decentralized matching process across multiple markets with multiple assets. The model is consistent across both the micro and macroeconomic levels, by providing a detailed, comprehensive, and rigorous accounting of real and financial flows and stocks. We implement the model using a brand new Java programming platform, explicitly designed for AB-SFC models.

  5. Agent-Based Modeling and Simulation of Child Maltreatment and Child Maltreatment Prevention

    OpenAIRE

    Xiaolin Hu; Nicholas Keller

    2015-01-01

    This paper presents an agent-based model that simulates the dynamics of child maltreatment and child maltreatment prevention. The developed model follows the principles of complex systems science and explicitly models a community and its families with multi-level factors across the social ecology. Each agent includes behavioral/cognitive modeling to account for the behavioral/cognitive process of child maltreatment. Simulation of child maltreatment prevention is also supported to evaluate the...

  6. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  7. A Guide for Newcomers to Agent-Based Modeling in the Social Sciences

    OpenAIRE

    Axelrod, Robert; Tesfatsion, Leigh

    2006-01-01

    This guide provides pointers to introductory readings, software, and other materials to help newcomers become acquainted with agent-based modeling in the social sciences. Related work can be accessed at: http://www.econ.iastate.edu/tesfatsi/ace.htm

  8. Learning Natural Selection in 4th Grade with Multi-Agent-Based Computational Models

    Science.gov (United States)

    Dickes, Amanda Catherine; Sengupta, Pratim

    2013-01-01

    In this paper, we investigate how elementary school students develop multi-level explanations of population dynamics in a simple predator-prey ecosystem, through scaffolded interactions with a multi-agent-based computational model (MABM). The term "agent" in an MABM indicates individual computational objects or actors (e.g., cars), and these…

  9. Communication Model for a Process Planning System Based on a Multi-agent

    Institute of Scientific and Technical Information of China (English)

    WANG Tao; DU Juan; WANG Chun-yan; LI Yun-xia

    2012-01-01

    This paper introduces a process planning system communication model based on a Multi-agent and all levels of the communication process are in described in detail. The KQML( Knowledge Query and Manipulation Language) language communication is introduced emphatically using the communication performatives of the KQML language to achieve communication between the agents among the process planning.

  10. Agent-based modeling: Methods and techniques for simulating human systems

    OpenAIRE

    Bonabeau, Eric

    2002-01-01

    Agent-based modeling is a powerful simulation modeling technique that has seen a number of applications in the last few years, including applications to real-world business problems. After the basic principles of agent-based simulation are briefly introduced, its four areas of application are discussed by using real-world applications: flow simulation, organizational simulation, market simulation, and diffusion simulation. For each category, one or several business applications are described ...

  11. Using an agent-based model to simulate children’s active travel to school

    OpenAIRE

    Yang, Yong; Diez-Roux, Ana V.

    2013-01-01

    Background Despite the multiple advantages of active travel to school, only a small percentage of US children and adolescents walk or bicycle to school. Intervention studies are in a relatively early stage and evidence of their effectiveness over long periods is limited. The purpose of this study was to illustrate the utility of agent-based models in exploring how various policies may influence children’s active travel to school. Methods An agent-based model was developed to simulate children...

  12. A standard protocol for describing individual-based and agent-based models

    Science.gov (United States)

    Grimm, Volker; Berger, Uta; Bastiansen, Finn; Eliassen, Sigrunn; Ginot, Vincent; Giske, Jarl; Goss-Custard, John; Grand, Tamara; Heinz, Simone K.; Huse, Geir; Huth, Andreas; Jepsen, Jane U.; Jorgensen, Christian; Mooij, Wolf M.; Muller, Birgit; Pe'er, Guy; Piou, Cyril; Railsback, Steven F.; Robbins, Andrew M.; Robbins, Martha M.; Rossmanith, Eva; Ruger, Nadja; Strand, Espen; Souissi, Sami; Stillman, Richard A.; Vabo, Rune; Visser, Ute; DeAngelis, Donald L.

    2006-01-01

    Simulation models that describe autonomous individual organisms (individual based models, IBM) or agents (agent-based models, ABM) have become a widely used tool, not only in ecology, but also in many other disciplines dealing with complex systems made up of autonomous entities. However, there is no standard protocol for describing such simulation models, which can make them difficult to understand and to duplicate. This paper presents a proposed standard protocol, ODD, for describing IBMs and ABMs, developed and tested by 28 modellers who cover a wide range of fields within ecology. This protocol consists of three blocks (Overview, Design concepts, and Details), which are subdivided into seven elements: Purpose, State variables and scales, Process overview and scheduling, Design concepts, Initialization, Input, and Submodels. We explain which aspects of a model should be described in each element, and we present an example to illustrate the protocol in use. In addition, 19 examples are available in an Online Appendix. We consider ODD as a first step for establishing a more detailed common format of the description of IBMs and ABMs. Once initiated, the protocol will hopefully evolve as it becomes used by a sufficiently large proportion of modellers.

  13. High performance computing for three-dimensional agent-based molecular models.

    Science.gov (United States)

    Pérez-Rodríguez, G; Pérez-Pérez, M; Fdez-Riverola, F; Lourenço, A

    2016-07-01

    Agent-based simulations are increasingly popular in exploring and understanding cellular systems, but the natural complexity of these systems and the desire to grasp different modelling levels demand cost-effective simulation strategies and tools. In this context, the present paper introduces novel sequential and distributed approaches for the three-dimensional agent-based simulation of individual molecules in cellular events. These approaches are able to describe the dimensions and position of the molecules with high accuracy and thus, study the critical effect of spatial distribution on cellular events. Moreover, two of the approaches allow multi-thread high performance simulations, distributing the three-dimensional model in a platform independent and computationally efficient way. Evaluation addressed the reproduction of molecular scenarios and different scalability aspects of agent creation and agent interaction. The three approaches simulate common biophysical and biochemical laws faithfully. The distributed approaches show improved performance when dealing with large agent populations while the sequential approach is better suited for small to medium size agent populations. Overall, the main new contribution of the approaches is the ability to simulate three-dimensional agent-based models at the molecular level with reduced implementation effort and moderate-level computational capacity. Since these approaches have a generic design, they have the major potential of being used in any event-driven agent-based tool. PMID:27372059

  14. Bounded Rational Managers Struggle with Talent Management - An Agent-based Modelling Approach

    DEFF Research Database (Denmark)

    Adamsen, Billy; Thomsen, Svend Erik

    This study applies an agent-based modeling approach to explore some aspects of an important managerial task: finding and cultivating talented individuals capable of creating value for their organization at some future state. Given that the term talent in talent management is an empty signifier...... of past success will provide failure rather than success in the future (Capelli.2008). Finally, we model the talent selection process either as a collective decision making process made by a group of managers or a decision process made by a single manager.It is argued that agent-based modeling is a useful...... method for studying this type of problems. The approach is particularly suitable to topics where understanding processes and their consequences is important. Agent-based models can include agents that are heterogeneous in their features and abilities, and can deal directly with the consequences...

  15. Software Cost Estimation Model Based on Integration of Multi-agent and Case-Based Reasoning

    Directory of Open Access Journals (Sweden)

    Hasan Al-Sakran

    2006-01-01

    Full Text Available Accurate software cost estimation is a vital task that affects the firm's software investment decisions before committing required resources to that project or bidding for a contract. This study proposes an improved Case-Based Reasoning (CBR approach integrated with multi-agent technology to retrieve similar projects from multi-organizational distributed datasets. The study explores the possibility of building a software cost estimation model by collecting software cost data from distributed predefined project cost databases. The model applying CBR method to find similar projects in historical data derived from measured software projects developed by different organizations.

  16. Agent-based conceptual model representation using BPMN

    OpenAIRE

    Onggo, Stephan; Karpat, Onder

    2011-01-01

    In a simulation project, a good conceptual model representation is critical for communicating conceptual models between stakeholders. A conceptual model describes the problem domain and model specifications. The description of the problem domain includes the objectives, inputs, outputs, content, assumptions and simplifications made in the model. The model specifications are used to specify the model’s behavior. This article focuses on the representation of the model content (structure, bounda...

  17. Techniques, Advantages and Problems of Agent Based Modeling for Traffic Simulation

    Directory of Open Access Journals (Sweden)

    Ali Bazghandi

    2012-01-01

    Full Text Available Agent-based modeling (ABM is a powerful simulation modeling technique in the last few years. ABM, as an approach to simulating the behavior of a complex system in which agents interact with each other and with their environment using simple local rules, is gaining popularity and widespread use in many areas. Successes of this approach in predicting traffic flow in metropolitan areas, the spread of infectious diseases, and the behavior of economic systems have generated further interest in this powerful technology. In this paper we focus on agent-based approach to traffic simulation, and investigate its benefits, difficulties and (microscopic-macroscopic techniques.

  18. An agent-based model of collective emotions in online communities

    Science.gov (United States)

    Schweitzer, F.; Garcia, D.

    2010-10-01

    We develop an agent-based framework to model the emergence of collective emotions, which is applied to online communities. Agent’s individual emotions are described by their valence and arousal. Using the concept of Brownian agents, these variables change according to a stochastic dynamics, which also considers the feedback from online communication. Agents generate emotional information, which is stored and distributed in a field modeling the online medium. This field affects the emotional states of agents in a non-linear manner. We derive conditions for the emergence of collective emotions, observable in a bimodal valence distribution. Dependent on a saturated or a superlinear feedback between the information field and the agent’s arousal, we further identify scenarios where collective emotions only appear once or in a repeated manner. The analytical results are illustrated by agent-based computer simulations. Our framework provides testable hypotheses about the emergence of collective emotions, which can be verified by data from online communities.

  19. An agent-based computational model for tuberculosis spreading on age-structured populations

    Science.gov (United States)

    Graciani Rodrigues, C. C.; Espíndola, Aquino L.; Penna, T. J. P.

    2015-06-01

    In this work we present an agent-based computational model to study the spreading of the tuberculosis (TB) disease on age-structured populations. The model proposed is a merge of two previous models: an agent-based computational model for the spreading of tuberculosis and a bit-string model for biological aging. The combination of TB with the population aging, reproduces the coexistence of health states, as seen in real populations. In addition, the universal exponential behavior of mortalities curves is still preserved. Finally, the population distribution as function of age shows the prevalence of TB mostly in elders, for high efficacy treatments.

  20. Income Tax Evasion Dynamics: Evidence from an Agent-based Econophysics Model

    CERN Document Server

    Pickhardt, Michael

    2011-01-01

    We analyze income tax evasion dynamics in a standard model of statistical mechanics, the Ising model of ferromagnetism. However, in contrast to previous research, we use an inhomogeneous multi-dimensional Ising model where the local degrees of freedom (agents) are subject to a specific social temperature and coupled to external fields which govern their social behavior. This new modeling frame allows for analyzing large societies of four different and interacting agent types. As a second novelty, our model may reproduce results from agent-based models that incorporate standard Allingham and Sandmo tax evasion features as well as results from existing two-dimensional Ising based tax evasion models. We then use our model for analyzing income tax evasion dynamics under different enforcement scenarios and point to some policy implications.

  1. Research on monocentric model of urbanization by agent-based simulation

    Science.gov (United States)

    Xue, Ling; Yang, Kaizhong

    2008-10-01

    Over the past years, GIS have been widely used for modeling urbanization from a variety of perspectives such as digital terrain representation and overlay analysis using cell-based data platform. Similarly, simulation of urban dynamics has been achieved with the use of Cellular Automata. In contrast to these approaches, agent-based simulation provides a much more powerful set of tools. This allows researchers to set up a counterpart for real environmental and urban systems in computer for experimentation and scenario analysis. This Paper basically reviews the research on the economic mechanism of urbanization and an agent-based monocentric model is setup for further understanding the urbanization process and mechanism in China. We build an endogenous growth model with dynamic interactions between spatial agglomeration and urban development by using agent-based simulation. It simulates the migration decisions of two main types of agents, namely rural and urban households between rural and urban area. The model contains multiple economic interactions that are crucial in understanding urbanization and industrial process in China. These adaptive agents can adjust their supply and demand according to the market situation by a learning algorithm. The simulation result shows this agent-based urban model is able to perform the regeneration and to produce likely-to-occur projections of reality.

  2. A Conceptual Generalized Nets Immunological Model for Agent based Exploration of Unknown Environment

    Directory of Open Access Journals (Sweden)

    Zlatogor Minchev

    2010-04-01

    Full Text Available Exploration of unknown environment in general is a very broad area, which in the current paper is addressed more to the agent based idea and robotics. As far as the agent and its further development - multiagent modus resembles real social systems the interaction between agents could benefit from the natural mechanisms like immune system. The paper presents a conceptual model for exploration of unknown environment, which extends the immune networks' idea with some self-immunization by means of dynamic anti-body generation with application both in mobile and i-mobile robotics (Smart Homes modeling and control, maintaining practical benefits like energy saving. The model is described in terms of the Generalized Nets Theory, thus providing a convenient and natural environment for agent-based modeling.

  3. Modelling and simulation of complex systems: an approach based on multi-level agents

    CERN Document Server

    Fougères, Alain-Jérôme

    2012-01-01

    A complex system is made up of many components with many interactions. So the design of systems such as simulation systems, cooperative systems or assistance systems includes a very accurate modelling of interactional and communicational levels. The agent-based approach provides an adapted abstraction level for this problem. After having studied the organizational context and communicative capacities of agentbased systems, to simulate the reorganization of a flexible manufacturing, to regulate an urban transport system, and to simulate an epidemic detection system, our thoughts on the interactional level were inspired by human-machine interface models, especially those in "cognitive engineering". To provide a general framework for agent-based complex systems modelling, we then proposed a scale of four behaviours that agents may adopt in their complex systems (reactive, routine, cognitive, and collective). To complete the description of multi-level agent models, which is the focus of this paper, we illustrate ...

  4. Reference model based consensus control of second-order multi-agent systems

    International Nuclear Information System (INIS)

    This paper deals with the consensus problem of multi-agent systems with second-order dynamics. The objective is to design algorithms such that all agents will have same positions and velocities. First, a reference model based consensus algorithm is proposed. It is proved that the consensus can be achieved if the communication graph has a spanning tree. Different from most of the consensus algorithms proposed in the literature, the parameters of the control laws are different among agents. Therefore, each agent can design its control law independently. Secondly, it gives a consensus algorithm for the case that the velocities of the agents are not available. Thirdly, the effectiveness of the input delay and the communication delay is considered. It shows that consensus can be achieved if the input delay of every agent is smaller than a bound related to parameters in its control law. Finally, some numerical examples are given to illustrate the proposed results. (general)

  5. An Agent-Based Model of Behavior in “Beauty Contest” Games

    OpenAIRE

    Nichols, Mark W.; Michael J. Radzicki

    2007-01-01

    Recently, computer simulation, particularly agent-based modeling, has grown in popularity as a method to uncover macro patterns and developments that emerge from simple micro behavior. The present paper combines both techniques by using protocol analysis to uncover player strategies in an experiment and encoding those strategies in an agent-based computer simulation. In particular, Keynes’ (1936) beauty contest analogy is simulated in a number-guessing context. Several researchers have conduc...

  6. Agent Based Modeling on Organizational Dynamics of Terrorist Network

    OpenAIRE

    Bo Li; Duoyong Sun; Renqi Zhu; Ze Li

    2015-01-01

    Modeling organizational dynamics of terrorist network is a critical issue in computational analysis of terrorism research. The first step for effective counterterrorism and strategic intervention is to investigate how the terrorists operate with the relational network and what affects the performance. In this paper, we investigate the organizational dynamics by employing a computational experimentation methodology. The hierarchical cellular network model and the organizational dynamics model ...

  7. Biomimetic agent based modelling using male Frog calling behaviour as a case study

    DEFF Research Database (Denmark)

    Jørgensen, Søren V.; Demazeau, Yves; Christensen-Dalsgaard, Jakob;

    2014-01-01

    A new agent-based modelling tool has been developed to allow the modelling of populations of individuals whose interactions are characterised by tightly timed dynamics. The tool was developed to model male frog calling dynamics, to facilitate research into what local rules may be employed by indi...

  8. Using Agent Base Models to Optimize Large Scale Network for Large System Inventories

    Science.gov (United States)

    Shameldin, Ramez Ahmed; Bowling, Shannon R.

    2010-01-01

    The aim of this paper is to use Agent Base Models (ABM) to optimize large scale network handling capabilities for large system inventories and to implement strategies for the purpose of reducing capital expenses. The models used in this paper either use computational algorithms or procedure implementations developed by Matlab to simulate agent based models in a principal programming language and mathematical theory using clusters, these clusters work as a high performance computational performance to run the program in parallel computational. In both cases, a model is defined as compilation of a set of structures and processes assumed to underlie the behavior of a network system.

  9. Artificial Immune Systems Metaphor for Agent Based Modeling of Crisis Response Operations

    CERN Document Server

    Khalil, Khaled M; Nazmy, Taymour T; Salem, Abdel-Badeeh M

    2010-01-01

    Crisis response requires information intensive efforts utilized for reducing uncertainty, calculating and comparing costs and benefits, and managing resources in a fashion beyond those regularly available to handle routine problems. This paper presents an Artificial Immune Systems (AIS) metaphor for agent based modeling of crisis response operations. The presented model proposes integration of hybrid set of aspects (multi-agent systems, built-in defensive model of AIS, situation management, and intensity-based learning) for crisis response operations. In addition, the proposed response model is applied on the spread of pandemic influenza in Egypt as a case study.

  10. An Agent-Based Model for Studying Child Maltreatment and Child Maltreatment Prevention

    Science.gov (United States)

    Hu, Xiaolin; Puddy, Richard W.

    This paper presents an agent-based model that simulates the dynamics of child maltreatment and child maltreatment prevention. The developed model follows the principles of complex systems science and explicitly models a community and its families with multi-level factors and interconnections across the social ecology. This makes it possible to experiment how different factors and prevention strategies can affect the rate of child maltreatment. We present the background of this work and give an overview of the agent-based model and show some simulation results.

  11. CACM: A New Coordination Model in Mobile Agent-Based Information Retrieval Applications

    Institute of Scientific and Technical Information of China (English)

    TANGXinhuai; ZHANGYaying; YAOYinxiong; YOUJinyuan

    2005-01-01

    In mobile agent systems, an application may be composed of several mobile agents that cooperatively perform a task. Multiple mobile agents need to communicate and interact with each other to accomplish their cooperative goal. Coordination model aims to provide solutions to interactions between concurrent activities, hiding the computing details and focusing on interaction between activities. A Context-aware coordination model (CACM), which combines mobility and coordination, is proposed for mobile agent applications, i.e. in mobile agent based information retrieval applications. The context-aware coordination model transfers interactions between agents from globally coupling interactions to locally uncoupling tuple space interactions. In addition, programmable tuple space is adopted to solve the problems of context-aware coordination introduced by mobility and data heterogeneity in mobile agent systems. Furthermore, environment specific and application specific coordination policy can be integrated into the programmable tuple space for customized requirements. Finally an application sample system-information retrieval in mobile agent applications is carried out to test the performance of the proposed model.

  12. Landscape Epidemiology Modeling Using an Agent-Based Model and a Geographic Information System

    Directory of Open Access Journals (Sweden)

    S. M. Niaz Arifin

    2015-05-01

    Full Text Available A landscape epidemiology modeling framework is presented which integrates the simulation outputs from an established spatial agent-based model (ABM of malaria with a geographic information system (GIS. For a study area in Kenya, five landscape scenarios are constructed with varying coverage levels of two mosquito-control interventions. For each scenario, maps are presented to show the average distributions of three output indices obtained from the results of 750 simulation runs. Hot spot analysis is performed to detect statistically significant hot spots and cold spots. Additional spatial analysis is conducted using ordinary kriging with circular semivariograms for all scenarios. The integration of epidemiological simulation-based results with spatial analyses techniques within a single modeling framework can be a valuable tool for conducting a variety of disease control activities such as exploring new biological insights, monitoring epidemiological landscape changes, and guiding resource allocation for further investigation.

  13. Modeling the Information Age Combat Model: An Agent-Based Simulation of Network Centric Operations

    Science.gov (United States)

    Deller, Sean; Rabadi, Ghaith A.; Bell, Michael I.; Bowling, Shannon R.; Tolk, Andreas

    2010-01-01

    The Information Age Combat Model (IACM) was introduced by Cares in 2005 to contribute to the development of an understanding of the influence of connectivity on force effectiveness that can eventually lead to quantitative prediction and guidelines for design and employment. The structure of the IACM makes it clear that the Perron-Frobenius Eigenvalue is a quantifiable metric with which to measure the organization of a networked force. The results of recent experiments presented in Deller, et aI., (2009) indicate that the value of the Perron-Frobenius Eigenvalue is a significant measurement of the performance of an Information Age combat force. This was accomplished through the innovative use of an agent-based simulation to model the IACM and represents an initial contribution towards a new generation of combat models that are net-centric instead of using the current platform-centric approach. This paper describes the intent, challenges, design, and initial results of this agent-based simulation model.

  14. Agent-based Models in Synthetic Biology: Tools for Simulation and Prospects

    Directory of Open Access Journals (Sweden)

    E.V.Krishnamurthy

    2012-03-01

    Full Text Available We describe a multiset of agents based modeling and simulation paradigm for synthetic biology. The multiset of agentsbased programming paradigm, can be interpreted as the outcome arising out of deterministic, nondeterministic or stochastic interaction among elements in a multiset object space, that includes the environment. These interactions are like chemical reactions and the evolution of the multiset can emulate the system biological functions. Since the reaction rules are inherently parallel, any number of actions can be performed cooperatively or competitively among the subsets of elements, so that the elements evolve toward equilibrium or emergent state. Practical realization of this paradigm for system biological simulation is achieved through the concept of transactional style programming with agents, as well as soft computing (neural- network principles. Also we briefly describe currently available tools for agent-based-modeling, simulation and animation.

  15. An Agent-Based Model of Endogenous Technological Change -- An Extension to the Grubler-Gritsevskyi Model

    OpenAIRE

    T. Ma

    2006-01-01

    Based on earlier, pioneering work done at IIASA, this paper presents a model of endogenous technological change under the three potential most important "stylized facts": increasing returns to adoption, uncertainty, and heterogeneous agents following diverse technology development and adoption strategies. As an intermediary step towards the final, long-term research objective of developing a multi-agent model, this paper deals with two heterogeneous agents, a risk-taking one and a risk-aversi...

  16. Simulation of multi-agent manufacturing systems using agent-based modelling platforms

    OpenAIRE

    Barbosa, José; Leitão, Paulo

    2011-01-01

    Multi-agent systems (MAS) are driving the way to design and engineer control solutions that exhibit flexibility, adaptation and reconfigurability, which are important advantages over traditional centralized systems. The understanding, design and testing of such distributed agentbased approaches, and particularly those exhibiting self-* properties, are usually a hard task. Simulation assumes a crucial role to analyse the behaviour of MAS solutions during the design phase and before its deploym...

  17. Understanding Group/Party Affiliation Using Social Networks and Agent-Based Modeling

    Science.gov (United States)

    Campbell, Kenyth

    2012-01-01

    The dynamics of group affiliation and group dispersion is a concept that is most often studied in order for political candidates to better understand the most efficient way to conduct their campaigns. While political campaigning in the United States is a very hot topic that most politicians analyze and study, the concept of group/party affiliation presents its own area of study that producers very interesting results. One tool for examining party affiliation on a large scale is agent-based modeling (ABM), a paradigm in the modeling and simulation (M&S) field perfectly suited for aggregating individual behaviors to observe large swaths of a population. For this study agent based modeling was used in order to look at a community of agents and determine what factors can affect the group/party affiliation patterns that are present. In the agent-based model that was used for this experiment many factors were present but two main factors were used to determine the results. The results of this study show that it is possible to use agent-based modeling to explore group/party affiliation and construct a model that can mimic real world events. More importantly, the model in the study allows for the results found in a smaller community to be translated into larger experiments to determine if the results will remain present on a much larger scale.

  18. Pain expressiveness and altruistic behavior: an exploration using agent-based modeling.

    Science.gov (United States)

    de C Williams, Amanda C; Gallagher, Elizabeth; Fidalgo, Antonio R; Bentley, Peter J

    2016-03-01

    Predictions which invoke evolutionary mechanisms are hard to test. Agent-based modeling in artificial life offers a way to simulate behaviors and interactions in specific physical or social environments over many generations. The outcomes have implications for understanding adaptive value of behaviors in context. Pain-related behavior in animals is communicated to other animals that might protect or help, or might exploit or predate. An agent-based model simulated the effects of displaying or not displaying pain (expresser/nonexpresser strategies) when injured and of helping, ignoring, or exploiting another in pain (altruistic/nonaltruistic/selfish strategies). Agents modeled in MATLAB interacted at random while foraging (gaining energy); random injury interrupted foraging for a fixed time unless help from an altruistic agent, who paid an energy cost, speeded recovery. Environmental and social conditions also varied, and each model ran for 10,000 iterations. Findings were meaningful in that, in general, contingencies that evident from experimental work with a variety of mammals, over a few interactions, were replicated in the agent-based model after selection pressure over many generations. More energy-demanding expression of pain reduced its frequency in successive generations, and increasing injury frequency resulted in fewer expressers and altruists. Allowing exploitation of injured agents decreased expression of pain to near zero, but altruists remained. Decreasing costs or increasing benefits of helping hardly changed its frequency, whereas increasing interaction rate between injured agents and helpers diminished the benefits to both. Agent-based modeling allows simulation of complex behaviors and environmental pressures over evolutionary time. PMID:26655734

  19. Combining Bayesian Networks and Agent Based Modeling to develop a decision-support model in Vietnam

    Science.gov (United States)

    Nong, Bao Anh; Ertsen, Maurits; Schoups, Gerrit

    2016-04-01

    Complexity and uncertainty in natural resources management have been focus themes in recent years. Within these debates, with the aim to define an approach feasible for water management practice, we are developing an integrated conceptual modeling framework for simulating decision-making processes of citizens, in our case in the Day river area, Vietnam. The model combines Bayesian Networks (BNs) and Agent-Based Modeling (ABM). BNs are able to combine both qualitative data from consultants / experts / stakeholders, and quantitative data from observations on different phenomena or outcomes from other models. Further strengths of BNs are that the relationship between variables in the system is presented in a graphical interface, and that components of uncertainty are explicitly related to their probabilistic dependencies. A disadvantage is that BNs cannot easily identify the feedback of agents in the system once changes appear. Hence, ABM was adopted to represent the reaction among stakeholders under changes. The modeling framework is developed as an attempt to gain better understanding about citizen's behavior and factors influencing their decisions in order to reduce uncertainty in the implementation of water management policy.

  20. Modeling and analysis of an agent-based model for Chinese stock market

    Science.gov (United States)

    Yang, Chun-Xia; Wang, Rui; Hu, Sen

    2013-11-01

    We constructed an agent-based stock market model which concisely describe investors' heterogeneity and adaptability by introducing price sensitivity and feedback time. Under different parameters, the peak and fat-tail property of return distribution is produced and the obtained statistic values coincide with empirical results: the center peak exponents range from -0.787 to -0.661, and the tail exponents range from -4.29 to -2.37. Besides, long-term correlation in volatility is examined by DFA1 method, and the obtained exponent α is 0.803, which also coincides with the exponent of 0.78 found in real market.

  1. A Novel Application of Agent-based Modeling: Projecting Water Access and Availability Using a Coupled Hydrologic Agent-based Model in the Nzoia Basin, Kenya

    Science.gov (United States)

    Le, A.; Pricope, N. G.

    2015-12-01

    Projections indicate that increasing population density, food production, and urbanization in conjunction with changing climate conditions will place stress on water resource availability. As a result, a holistic understanding of current and future water resource distribution is necessary for creating strategies to identify the most sustainable means of accessing this resource. Currently, most water resource management strategies rely on the application of global climate predictions to physically based hydrologic models to understand potential changes in water availability. However, the need to focus on understanding community-level social behaviors that determine individual water usage is becoming increasingly evident, as predictions derived only from hydrologic models cannot accurately represent the coevolution of basin hydrology and human water and land usage. Models that are better equipped to represent the complexity and heterogeneity of human systems and satellite-derived products in place of or in conjunction with historic data significantly improve preexisting hydrologic model accuracy and application outcomes. We used a novel agent-based sociotechnical model that combines the Soil and Water Assessment Tool (SWAT) and Agent Analyst and applied it in the Nzoia Basin, an area in western Kenya that is becoming rapidly urbanized and industrialized. Informed by a combination of satellite-derived products and over 150 household surveys, the combined sociotechnical model provided unique insight into how populations self-organize and make decisions based on water availability. In addition, the model depicted how population organization and current management alter water availability currently and in the future.

  2. Econophysics: Empirical facts and agent-based models

    OpenAIRE

    Anirban Chakraborti; Ioane Muni Toke; Marco Patriarca; Frederic Abergel

    2009-01-01

    This article aims at reviewing recent empirical and theoretical developments usually grouped under the term Econophysics. Since its name was coined in 1995 by merging the words Economics and Physics, this new interdisciplinary field has grown in various directions: theoretical macroeconomics (wealth distributions), microstructure of financial markets (order book modelling), econometrics of financial bubbles and crashes, etc. In the first part of the review, we discuss on the emergence of Econ...

  3. Architectural considerations for agent-based national scale policy models : LDRD final report.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Strip, David R.

    2007-09-01

    The need to anticipate the consequences of policy decisions becomes ever more important as the magnitude of the potential consequences grows. The multiplicity of connections between the components of society and the economy makes intuitive assessments extremely unreliable. Agent-based modeling has the potential to be a powerful tool in modeling policy impacts. The direct mapping between agents and elements of society and the economy simplify the mapping of real world functions into the world of computation assessment. Our modeling initiative is motivated by the desire to facilitate informed public debate on alternative policies for how we, as a nation, provide healthcare to our population. We explore the implications of this motivation on the design and implementation of a model. We discuss the choice of an agent-based modeling approach and contrast it to micro-simulation and systems dynamics approaches.

  4. An Agent-Based Model of New Venture Creation: Conceptual Design for Simulating Entrepreneurship

    Science.gov (United States)

    Provance, Mike; Collins, Andrew; Carayannis, Elias

    2012-01-01

    There is a growing debate over the means by which regions can foster the growth of entrepreneurial activity in order to stimulate recovery and growth of their economies. On one side, agglomeration theory suggests the regions grow because of strong clusters that foster knowledge spillover locally; on the other side, the entrepreneurial action camp argues that innovative business models are generated by entrepreneurs with unique market perspectives who draw on knowledge from more distant domains. We will show you the design for a novel agent-based model of new venture creation that will demonstrate the relationship between agglomeration and action. The primary focus of this model is information exchange as the medium for these agent interactions. Our modeling and simulation study proposes to reveal interesting relationships in these perspectives, offer a foundation on which these disparate theories from economics and sociology can find common ground, and expand the use of agent-based modeling into entrepreneurship research.

  5. A SIMULATION OF AGENT-BASED MODELS FOR HIGH FREQUENCY TRADING ON THE STOCK EXCHANGE MARKET

    OpenAIRE

    Diana Dezsi

    2013-01-01

    High frequency computer-based trading (HFT) represents a challenging topic nowadays, mainly due to the controversy it creates among investors on the financial market. The hereto paper uses two types of agent-based models, one with zero-intelligence traders and the other with intelligent traders in order to simulate the tick-by-tick high frequency trading market for ten US stocks. The results show that in almost all the cases the intelligent agent-based model performed better when compared to ...

  6. A Framework for Model-Based Inquiry Through Agent-Based Programming

    Science.gov (United States)

    Xiang, Lin; Passmore, Cynthia

    2015-04-01

    There has been increased recognition in the past decades that model-based inquiry (MBI) is a promising approach for cultivating deep understandings by helping students unite phenomena and underlying mechanisms. Although multiple technology tools have been used to improve the effectiveness of MBI, there are not enough detailed examinations of how agent-based programmable modeling (ABPM) tools influence students' MBI learning. The present collective case study sought to contribute by closely investigating ABPM-supported MBI processes for 8th grade students learning about natural selection and adaptation. Eight 8th grade students in groups of 2-3 spent 15 h during a span of 4 weeks collaboratively programming simulations of adaptation based on the natural selection model, using an ABPM tool named NetLogo. The entire programming processes of these learning groups, up to 50 h, were videotaped and then analyzed using mixed methods. Our analysis revealed that the programming task created a context that calls for nine types of MBI actions. These MBI actions were related to both phenomena and the underlying model. Results also showed that students' programming processes took place in consecutive programming cycles and aligned with iterative MBI cycles. A framework for ABPM-supported MBI learning is proposed based upon the findings. Implications in developing MBI instruction involving ABPM tools are discussed.

  7. Agent-Based Game Theory Modeling for Driverless Vehicles at Intersections

    OpenAIRE

    Rakha, Hesham A.; Zohdy, Ismail; Kamalanathsharma, Raj K.

    2013-01-01

    This report presents three research efforts that were published in various journals. The first research effort presents a reactive-driving agent based algorithm for modeling driver left turn gap acceptance behavior at signalized intersections. This model considers the interaction between driver characteristics and vehicle physical capabilities. The model explicitly captures the vehicle constraints on driving behavior using a vehicle dynamics model. In addition, the model uses the driver's inp...

  8. Modeling Multi-Mobile Agents System Based on Coalition Signature Mechanism Using UML

    Institute of Scientific and Technical Information of China (English)

    SUNZhixin; HUANGHaiping; WANGRuchuan

    2004-01-01

    With the development of electronic commerce and agent techniques, multi-mobile agents cooperation can not only improve the efficiency of electronic business trade, but more importantly, it has a comprehensive applicative value in solving the security issues of mobile agent system. This paper firstly describes the mechanism of multi-mobile agents coalition signature aiming at the system security. Subsequently it brings forward a basic architecture of Multi-mobile agents system (MMAS) based on the design pattern of multi-mobile agents. The paper uses the diagrs_rn of UML, such as use case diagram, class diagram and sequence diagram to build the detailed model of the coalition signature and multi-mobile agents cooperation results. Through security analysis, we find that multimobile agents cooperation and interaction can solve some security problems of mobile agents in transfer, and also it can improve the efficiency of business trade. These results indicate that MMAS has a high security performance and can be widely used in E-commerce trade.

  9. Testing an agent-based model of bacterial cell motility: How nutrient concentration affects speed distribution

    OpenAIRE

    Garcia, Victor; Birbaumer, Mirko; Schweitzer, Frank

    2011-01-01

    We revisit a recently proposed agent-based model of active biological motion and compare its predictions with own experimental findings for the speed distribution of bacterial cells, \\emph{Salmonella typhimurium}. Agents move according to a stochastic dynamics and use energy stored in an internal depot for metabolism and active motion. We discuss different assumptions of how the conversion from internal to kinetic energy $d(v)$ may depend on the actual speed, to conclude that $d_{2}v^{\\xi}$ w...

  10. Modeling of the Cloud Interconnected Human Friendly Multi-Agent Based Sustainable Power Controller

    OpenAIRE

    Gricius, G.; Drungilas, D.; Guseinovaitė, J.; Grigaitis, K.; Bielskis, A. A.

    2013-01-01

    The paper presents model of the cloud interconnected multi-agent human friendly sustainable power controller (Controller). The Controller is based on the human ambient comfort affect reward index (ACAR index). The ACAR index depends on human physiological parameters: the temperature, the ECG- electrocardiogram and the EDA-electro-dermal activity. These physiological parameters are used for sustainable power control by multi-agent system developed as the cloud interconnected, instrumented, and...

  11. Multi-agents modelling of EV purchase willingness based on questionaires

    DEFF Research Database (Denmark)

    Xue, Yusheng; Wu, Juai; Xie, Dongliang;

    2015-01-01

    and the algorithm is validated by comparing the agent-based Monte Carlo simulation results with the questionnaire-based deduction results. With the aid of agent models, the effects of minority agents with specific preferences on the results are also discussed.......Traditional experimental economics methods often consume enormous resources of qualified human participants,and the inconsistence of a participant’s decisions among repeated trials prevents investigation from sensitivity analyses. The problem can be solved if computer agents are capable...... of generating similar behaviors as the given participants in experiments. An experimental economics based analysis method is presented to extract deep information from questionnaire data and emulate any number of participants.Taking the customers’ willingness to purchase electric vehicles(EVs) as an example...

  12. A new distributed computing model of mobile spatial information service grid based on mobile agent

    Science.gov (United States)

    Tian, Gen; Liu, Miao-long

    2009-10-01

    A new distributed computing model of mobile spatial information service is studied based on grid computing environment. Key technologies are presented in the model, including mobile agent (MA) distributed computing, grid computing, spatial data model, location based service (LBS), global positioning system (GPS), code division multiple access (CDMA), transfer control protocol/internet protocol (TCP/IP), and user datagram protocol (UDP). In order to deal with the narrow bandwidth and instability of the wireless internet, distributed organization of tremendous spatial data, limited processing speed and low memory of mobile devices, a new mobile agent based mobile spatial information service grid (MSISG) architecture is further proposed that has good load balance, high processing efficiency, less network communication and thus suitable for mobile distributed computing environment. It can provide applications of spatial information distributed computing and mobile service. The theories and technologies architecture of MSISG are built originally from the base, including spatial information mobile agent model, distributed grid geographic information system (GIS) server model, mobile agent server model and mobile GIS client model. An application system for MSISG is therefore developed authorship by visual c++ and embedded visual c++. A field test is carried out through this system in Shanghai, and the results show that the proposed model and methods are feasible and adaptable for mobile spatial information service.

  13. The Agent-based Model on Real-time Data Warehousing

    Institute of Scientific and Technical Information of China (English)

    YouzhiXu; JieShen

    2004-01-01

    The conventional data warehouse can only analyze historical data. This paper proposes a concept of agent-based real-time data warehouse in BI system, With this model we can improve the real-time performance of data warehouse. On the other hand, the BI system flexibility is enhanced in this model, which makes it much more efficient to manage the distributed environment.

  14. Decision-Making in Agent-Based Models of Migration: State of the Art and Challenges

    NARCIS (Netherlands)

    Klabunde, A.; Willekens, F.J.

    2016-01-01

    We review agent-based models (ABM) of human migration with respect to their decision-making rules. The most prominent behavioural theories used as decision rules are the random utility theory, as implemented in the discrete choice model, and the theory of planned behaviour. We identify the critical

  15. Research on Application of Power System Reliability Model Based on Principal-agent Mechanism

    Directory of Open Access Journals (Sweden)

    Shaomei Yang

    2012-02-01

    Full Text Available Power system reliability has been a widespread concern. With the continuous development of the electricity market, there has been a serious conflict, which between social obligations and necessary requirement. The so-called social obligation is that the power industry must ensure the power system operation reliability; the so-called necessary requirement is that the power industry must solve the power market operation economics. The power system operation reliability is serious challenge, so we must establish a new mechanism adapting to the electricity market, and ensure the power system operation reliability. In this paper, we have researched the model and method based on the principal-agent mechanism from three aspects, which are the reliability principal-agent model starting point, principal-agent model analysis and design, and information transparency level impact analysis. On this basis, we proposed the reliability management model based on the principal-agent mechanism, and carried out example analysis. The example analysis shows that through establishing the principal-agent relationship between power enterprises and the user, the entire power system reliability resources would be more efficient configuration to further enhance the entire society electricity reliability benefits. Further evidence that the principal-agent mechanism is scientific and applicability in the power system reliability study.

  16. Personalised learning object based on multi-agent model and learners’ learning styles

    OpenAIRE

    Noppamas Pukkhem

    2011-01-01

    A multi-agent model is proposed in which learning styles and a word analysis technique to create a learning object recommendation system are used. On the basis of a learning style-based design, a concept map combination model is proposed to filter out unsuitable learning concepts from a given course. Our learner model classifies learners into eight styles and implements compatible computational methods consisting of three recommendations: i) non-personalised, ii) preferred feature-based, and ...

  17. Modelling and simulation of complex systems: an approach based on multi-level agents

    Directory of Open Access Journals (Sweden)

    Alain-Jerome Fougeres

    2011-11-01

    Full Text Available A complex system is made up of many components with many interactions. So the design of systems such as simulation systems, cooperative systems or assistance systems includes a very accurate modelling of interactional and communicational levels. The agent-based approach provides an adapted abstraction level for this problem. After having studied the organizational context and communicative capacities of agent-based systems, to simulate the reorganization of a flexible manufacturing, to regulate an urban transport system, and to simulate an epidemic detection system, our thoughts on the interactional level were inspired by human-machine interface models, especially those in cognitive engineering To provide a general framework for agent-based complex systems modelling, we then proposed a scale of four behaviours that agents may adopt in their complex systems (reactive, routine, cognitive, and collective. To complete the description of multi-level agent models, which is the focus of this paper, we illustrate our modelling and discuss our ongoing work on each level.

  18. Emergence of a Snake-Like Structure in Mobile Distributed Agents: An Exploratory Agent-Based Modeling Approach

    Directory of Open Access Journals (Sweden)

    Muaz A. Niazi

    2014-01-01

    Full Text Available The body structure of snakes is composed of numerous natural components thereby making it resilient, flexible, adaptive, and dynamic. In contrast, current computer animations as well as physical implementations of snake-like autonomous structures are typically designed to use either a single or a relatively smaller number of components. As a result, not only these artificial structures are constrained by the dimensions of the constituent components but often also require relatively more computationally intensive algorithms to model and animate. Still, these animations often lack life-like resilience and adaptation. This paper presents a solution to the problem of modeling snake-like structures by proposing an agent-based, self-organizing algorithm resulting in an emergent and surprisingly resilient dynamic structure involving a minimal of interagent communication. Extensive simulation experiments demonstrate the effectiveness as well as resilience of the proposed approach. The ideas originating from the proposed algorithm can not only be used for developing self-organizing animations but can also have practical applications such as in the form of complex, autonomous, evolvable robots with self-organizing, mobile components with minimal individual computational capabilities. The work also demonstrates the utility of exploratory agent-based modeling (EABM in the engineering of artificial life-like complex adaptive systems.

  19. Reverse engineering a social agent-based hidden markov model--visage.

    Science.gov (United States)

    Chen, Hung-Ching Justin; Goldberg, Mark; Magdon-Ismail, Malik; Wallace, William A

    2008-12-01

    We present a machine learning approach to discover the agent dynamics that drives the evolution of the social groups in a community. We set up the problem by introducing an agent-based hidden Markov model for the agent dynamics: an agent's actions are determined by micro-laws. Nonetheless, We learn the agent dynamics from the observed communications without knowing state transitions. Our approach is to identify the appropriate micro-laws corresponding to an identification of the appropriate parameters in the model. The model identification problem is then formulated as a mixed optimization problem. To solve the problem, we develop a multistage learning process for determining the group structure, the group evolution, and the micro-laws of a community based on the observed set of communications among actors, without knowing the semantic contents. Finally, to test the quality of our approximations and the feasibility of the approach, we present the results of extensive experiments on synthetic data as well as the results on real communities, such as Enron email and Movie newsgroups. Insight into agent dynamics helps us understand the driving forces behind social evolution. PMID:19145665

  20. Agent-based modelling as scientific method: a case study analysing primate social behaviour.

    Science.gov (United States)

    Bryson, Joanna J; Ando, Yasushi; Lehmann, Hagen

    2007-09-29

    A scientific methodology in general should provide two things: first, a means of explanation and, second, a mechanism for improving that explanation. Agent-based modelling (ABM) is a method that facilitates exploring the collective effects of individual action selection. The explanatory force of the model is the extent to which an observed meta-level phenomenon can be accounted for by the behaviour of its micro-level actors. This article demonstrates that this methodology can be applied to the biological sciences; agent-based models, like any other scientific hypotheses, can be tested, critiqued, generalized or specified. We review the state of the art for ABM as a methodology for biology and then present a case study based on the most widely published agent-based model in the biological sciences: Hemelrijk's DomWorld, a model of primate social behaviour. Our analysis shows some significant discrepancies between this model and the behaviour of the macaques, the genus used for our analysis. We also demonstrate that the model is not fragile: its other results are still valid and can be extended to compensate for these problems. This robustness is a standard advantage of experiment-based artificial intelligence modelling techniques over analytic modelling. PMID:17434852

  1. Agent-Based Modeling of Harvest Decisions by Small Scale Forest Landowners in Maine, USA

    Directory of Open Access Journals (Sweden)

    Jessica E. Leahy

    2013-01-01

    Full Text Available Small-scale forests are an excellent example of coupled social-ecological systems, which involve human and biophysical subsystems with complex two-way feedback interactions. The multifaceted nature of landowner decisions drives a significant need to better understand decision-making processes, reactions to policy, and combined impacts on ecosystems in a comprehensive manner. Small-scale forests require an integrated approach to modeling the social and biophysical components comprehensively. Agent-based modeling involves modeling individualistic behavior and interpreting patterns that emerge. The interaction between agents and their environments makes this a valuable tool to assess repeated decisions of individual landowners responding to changing environmental conditions. Agent-based models can be used to determine potential ecological, economic, and social outcomes of landowner decisions and reactions to changing conditions. A forest landowner agent-based model experiment was developed to model timber harvesting in Maine, USA. We present baseline simulation results and compare the effect of a social change (an increased tax rate and a biophysical change (a pest outbreak resulting in increased tree mortality on the system. These three scenarios were analyzed using ANOVA and MANOVA tests on harvested hectares and landowner goal scores to assess landowner behavior and priorities by action. We conclude by reviewing implications for future modeling efforts.

  2. Platform-level Distributed Warfare Model-based on Multi-Agent System Framework

    Directory of Open Access Journals (Sweden)

    Xiong Li

    2012-05-01

    Full Text Available The multi-agent paradigm has become a useful tool in solving military problems. However, one of key challenges in multi-agent model for distributed warfare could be how to describe the microcosmic  tactical warfare platforms actions. In this paper, a platform-level distributed warfare model based on multi-agent system framework is designed to tackle this challenge. The basic ideas include:  Establishing multi-agent model by mapping from tactical warfare system’s members, i.e., warfare platforms, to respective agents; performing task decomposition and task allocation by using task-tree decomposition method and improved contract net protocol model technique; and implementing simulation by presenting battlefield terrain environment analysis algorithm based on grid approach. The  simulation demonstration results show that our model provides a feasible and effective approach to supporting the abstraction and representation of microcosmic tactical actions for complex warfare system.Defence Science Journal, 2012, 62(1, pp.180-186, DOI:http://dx.doi.org/10.14429/dsj.62.964

  3. An information theory based behavioral model for agent-based crowd simulations

    OpenAIRE

    Turkay, Çağatay; Turkay, Cagatay; Koç, Emre; Koc, Emre; Balcısoy, Selim; Balcisoy, Selim

    2010-01-01

    Crowds must be simulated believable in terms of their appearance and behavior to improve a virtual environment’s realism. Due to the complex nature of human behavior, realistic behavior of agents in crowd simulations is still a challenging problem. In this paper, we propose a novel behavioral model which builds analytical maps to control agents’ behavior adaptively with agent-crowd interaction formulations. We introduce information theoretical concepts to construct analytical maps automatical...

  4. PERFORMANCE EVALUATION FOR DAMPING CONTROLLERS OF POWER SYSTEMS BASED ON MULTI-AGENT MODELS

    Institute of Scientific and Technical Information of China (English)

    Ancheng XUE; Yiguang HONG

    2009-01-01

    This paper proposes a multi-layer multi-agent model for the performance evaluation of power systems, which is different from the existing multi-agent ones. To describe the impact of the structure of the networked power system, .the proposed model consists of three kinds of agents that form three layers: control agents such as the generators and associated controllers, information agents to exchange the information based on the wide area measurement system (WAMS) or transmit control signals to the power system stabilizers (PSSs), and network-node agents such as the generation nodes and load nodes connected with transmission lines. An optimal index is presented to evaluate the performance of damping controllers to the system's inter-area oscillation with respect to the information-layer topology.Then, the authors show that the inter-area information exchange is more powerful than the exchange within a given area to control the inter-area low frequency oscillation based on simulation analysis.

  5. Study on Agent Collaborative Work Model of Aircraft Spares Support Based on CSCW Environment

    Directory of Open Access Journals (Sweden)

    Hongfu Zuo

    2013-01-01

    Full Text Available The aircraft spares support activities involve several support units which are located in different places. For this reason, it is necessary to establish an information network of spares support to coordinate the activity of each support unit. This study focuses its research on creating an Agent collaborative work model of aircraft spares support based on CSCW environment to raise support level and reduce its costs. The author approaches and solves the problem first by designing three-level B/S structure mode for Agent after analyzing the design requirements of it based on CSCW environment and then by exploring the communication mode and collaborative work mechanism between Agent units and probing into the processes of cooperative work group, work flow and formation of support scheme. On the basis of the Agent collaborative work model, the author advances one collaborative control mathematical model under restriction of support level as well and conducts simulating test for the two models by relevant simulation software. The test result is that after collaborative work the support level rises from 93.87 to 97.01% and the total cost per unit time for support costs falls from 903 RMB to 877 RMB. Thus, the optimization of Agent parameters for aircraft spares comes true and relevance of total support cost and support level is determined.

  6. Agent-based modeling of malaria vectors: the importance of spatial simulation

    OpenAIRE

    Bomblies, Arne

    2014-01-01

    Background The modeling of malaria vector mosquito populations yields great insight into drivers of malaria transmission at the village scale. Simulation of individual mosquitoes as “agents” in a distributed, dynamic model domain may be greatly beneficial for simulation of spatial relationships of vectors and hosts. Methods In this study, an agent-based model is used to simulate the life cycle and movement of individual malaria vector mosquitoes in a Niger Sahel village, with individual simul...

  7. Investigating Immune System Aging: System Dynamics and Agent-Based Modeling

    OpenAIRE

    Figueredo, Grazziela; Aickelin, Uwe

    2013-01-01

    System dynamics and agent based simulation models can both be used to model and understand interactions of entities within a population. Our modeling work presented here is concerned with understanding the suitability of the different types of simulation for the immune system aging problems and comparing their results. We are trying to answer questions such as: How fit is the immune system given a certain age? Would an immune boost be of therapeutic value, e.g. to improve the effectiveness...

  8. Social circles: a simple structure for agent-based social network models

    OpenAIRE

    Gilbert, GN; Hamill, L

    2009-01-01

    None of the standard network models fit well with sociological observations of real social networks. This paper presents a simple structure for use in agent-based models of large social networks. Taking the idea of social circles, it incorporates key aspects of large social networks such as low density, high clustering and assortativity of degree of connectivity. The model is very flexible and can be used to create a wide variety of artificial social worlds.

  9. A Collective Case Study of Secondary Students' Model-Based Inquiry on Natural Selection through Programming in an Agent-Based Modeling Environment

    Science.gov (United States)

    Xiang, Lin

    2011-01-01

    This is a collective case study seeking to develop detailed descriptions of how programming an agent-based simulation influences a group of 8th grade students' model-based inquiry (MBI) by examining students' agent-based programmable modeling (ABPM) processes and the learning outcomes. The context of the present study was a biology unit on…

  10. Genetic Algorithms for Agent-Based Infrastructure Interdependency Modeling and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    May Permann

    2007-03-01

    Today’s society relies greatly upon an array of complex national and international infrastructure networks such as transportation, electric power, telecommunication, and financial networks. This paper describes initial research combining agent-based infrastructure modeling software and genetic algorithms (GAs) to help optimize infrastructure protection and restoration decisions. This research proposes to apply GAs to the problem of infrastructure modeling and analysis in order to determine the optimum assets to restore or protect from attack or other disaster. This research is just commencing and therefore the focus of this paper is the integration of a GA optimization method with a simulation through the simulation’s agents.

  11. The knowledge management arena: agent-based modelling of the pig sector

    NARCIS (Netherlands)

    Osinga, S.A.

    2015-01-01

    Abstract belonging to PhD thesis:
    The knowledge management arena: agent-based modelling of the pig sector
    Sjoukje A. Osinga
    Wageningen University, Information technology group To be defended on 22nd of April, 2015
    Promotor: Em. Prof. ir AJM (Adrie) Beulens, I

  12. Targeting and timing promotional activities : An agent-based model for the takeoff of new products

    NARCIS (Netherlands)

    Delre, S. A.; Jager, W.; Bijmolt, T. H. A.; Janssen, M. A.

    2007-01-01

    Many marketing efforts focus on promotional activities that support the launch of new products. Promotional strategies may play a crucial role in the early stages of the product life cycle, and determine to a large extent the diffusion of a new product. This paper proposes an agent-based model to si

  13. A study of the diffusion of alternative fuel vehicles : An agent-based modeling approach

    NARCIS (Netherlands)

    Zhang, Ting; Gensler, Sonja; Garcia, Rosanna

    2011-01-01

    This paper demonstrates the use of an agent-based model (ABM) to investigate factors that can speed the diffusion of eco-innovations, namely alternative fuel vehicles (AFVs). The ABM provides the opportunity to consider the interdependencies inherent between key participants in the automotive indust

  14. An agent-based interaction model for Chinese personal income distribution

    Science.gov (United States)

    Zou, Yijiang; Deng, Weibing; Li, Wei; Cai, Xu

    2015-10-01

    The personal income distribution in China was studied by employing the data from China Household Income Projects (CHIP) between 1990 and 2002. It was observed that the low and middle income regions could be described by the log-normal law, while the large income region could be well fitted by the power law. To characterize these empirical findings, a stochastic interactive model with mean-field approach was discussed, and the analytic result shows that the wealth distribution is of the Pareto type. Then we explored the agent-based model on networks, in which the exchange of wealth among agents depends on their connectivity. Numerical results suggest that the wealth of agents would largely rely on their connectivity, and the Pareto index of the simulated wealth distributions is comparable to those of the empirical data. The Pareto behavior of the tails of the empirical wealth distributions is consistent with that of the 'mean-field' model, as well as numerical simulations.

  15. A Computational Agent-Based Modeling Approach for Competitive Wireless Service Market

    KAUST Repository

    Douglas, C C

    2011-04-01

    Using an agent-based modeling method, we study market dynamism with regard to wireless cellular services that are in competition for a greater market share and profit. In the proposed model, service providers and consumers are described as agents who interact with each other and actively participate in an economically well-defined marketplace. Parameters of the model are optimized using the Levenberg-Marquardt method. The quantitative prediction capabilities of the proposed model are examined through data reproducibility using past data from the U.S. and Korean wireless service markets. Finally, we investigate a disruptive market event, namely the introduction of the iPhone into the U.S. in 2007 and the resulting changes in the modeling parameters. We predict and analyze the impacts of the introduction of the iPhone into the Korean wireless service market assuming a release date of 2Q09 based on earlier data. © 2011 IEEE.

  16. Simulation of Land-Use Development, Using a Risk-Regarding Agent-Based Model

    Directory of Open Access Journals (Sweden)

    F. Hosseinali

    2012-01-01

    Full Text Available The aim of this paper is to study the spatial consequences of applying different Attitude Utility Functions (AUFs, which reflect peoples’ simplified psychological frames, to investment plans in land-use decision making. For this purpose, we considered and implemented an agent-based model with new methods for searching landscapes, for selecting parcels to develop, and for allowing competitions among agents. Besides this, GIS (Geographic Information Systems as a versatile and powerful medium of analyzing and representing spatial data is used. Our model is implemented on an artificial landscape in which land is being developed by agents. The agents are assumed to be mobile developers that are equipped with several land-related objectives. In this paper, agents mimic various risk-bearing attitudes and sometimes compete for developing the same parcel. The results reveal that patterns of land-use development are different in the two cases of regarding and disregarding AUFs. Therefore, it is considered here that using the attitudes of people towards risk helps the model to better simulate the decision making of land-use developers. The different attitudes toward risk used in this study can be attributed to different categories of developers based on sets of characteristics such as income, age, or education.

  17. Simulating GenCo bidding strategies in electricity markets with an agent-based model

    International Nuclear Information System (INIS)

    In this paper we use an agent-based simulation model, EMCAS, to analyze market power in electricity markets. We focus on the effect of congestion management on the ability of generating companies (GenCos) to raise prices beyond competitive levels. An 11-node test power system is used to compare a market design based on locational marginal pricing with a market design that uses system marginal pricing and congestion management by counter trading. Bidding strategies based on both physical and economic withholding are compared to a base case with production cost bidding. The results show that unilateral market power is exercised under both pricing mechanisms. However, the largest changes in consumer costs and GenCo profits due to strategic bidding occur under the locational marginal pricing scheme. The analysis also illustrates that agent-based modeling can contribute important insights into the complex interactions between the participants in transmission-constrained electricity markets. (Author)

  18. Developing an Agent-Based Model to Simulate Urban Land-Use Expansion (Case Study: Qazvin

    Directory of Open Access Journals (Sweden)

    F. Nourian

    2012-01-01

    Full Text Available Extended abstract1-IntroductionUrban land-use expansion is a challenging issue in developing countries. Increases in population as well as the immigration from the villages to the cities are the two major factors for that phenomenon. Those factors have reduced the influence of efforts that try to limit the cities’ boundaries. Thus, spatial planners always look for the models that simulate the expansion of urban land-uses and enable them to prevent unbalanced expansions of cities and guide the developments to the desired areas. Several models have been developed and evaluated for simulating urban land-use expansions. Despite the variety of the models, most of them have focused on simulating urban land-use expansions just around a city. Thus, the regional models that consider wider area are of primary importance.2- Theoretical basesIn this study a new agent-based model has been developed and implemented to simulate urban land-use expansion in Qazvin and Alborz regions of Qazvin state which have an area of 1620 square kilometers. In this model, land-use developers have been treated as agents that move in the landscape explicitly and assess the state of parcels for development. So, the environment of the model is raster. The agents are developed into five groups which have different aims. The agents may fall in competition to develop the same parcels. Moreover, due to the spatial essence of the problem, GIS were used to prepare the environment of agents’ movement and search and to aggregate and analyze the results.Two main steps can be recognized in this model: the Searching step and the Development step:Searching step: The agents are created and distributed in the districts. The selection of districts is probabilistic and is based on the primary probability of selection, assumed for districts. When agents go to the districts, at first they move randomly to the neighborhood of pre-developed areas. Wherever the agent starts its activities, it

  19. Exploring the cooperative regimes in an agent-based model: indirect reciprocity vs. selfish incentives

    Science.gov (United States)

    Fort, H.

    2003-08-01

    The self-organization in cooperative regimes in a simple mean-field version of a model based on “selfish” agents which play the Prisoner's Dilemma (PD) game is studied. The agents have no memory and use strategies not based on direct reciprocity nor “tags”. Two variables are assigned to each agent k at time t, measuring its capital C( k; t) and its probability of cooperation p( k; t). At each time step t a pair of agents interact by playing the PD game. These two agents update their probability of cooperation p( k; t) as follows: they compare the profits they made in this interaction δC( k; t) with an estimator ε( k; t) and, if δC( k; t)⩾ ε( k; t), agent i increases its p( k; t) while if δC( k; t)punishment)-are analyzed. It turns out that for all these 24 possibilities, after a transient, the system self-organizes into a stationary state with average equilibrium probability of cooperation p¯∞= constant>0 . Depending on the payoff matrix, there are different equilibrium states characterized by their average probability of cooperation and average equilibrium per capita income ( p¯∞, δC¯∞) .

  20. An Agent Based Intrusion Detection Model for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    B. M. Reshmi

    2006-01-01

    Full Text Available Intrusion detection has over the last few years, assumed paramount importance within the broad realm of network security, more so in case of wireless mobile ad hoc networks. The inherently vulnerable characteristics of wireless mobile ad hoc networks make them susceptible to attacks in-spite of some security measures, and it may be too late before any counter action can take effect. As such, there is a need to complement traditional security mechanisms with efficient intrusion detection and response systems. This paper proposes an agent-based model to address the aspect of intrusion detection in cluster based mobile wireless ad hoc network environment. The model comprises of a set of static and mobile agents, which are used to detect intrusions, respond to intrusions, and distribute selected and aggregated intrusion information to all other nodes in the network in an intelligent manner. The model is simulated to test its operation effectiveness by considering the performance parameters such as, detection rate, false positives, agent overheads, and intrusion information distribution time. Agent based approach facilitates flexible and adaptable security services. Also, it supports component based software engineering components such as maintainability, reachability, reusability, adaptability, flexibility, and customization.

  1. Evaluation Model for Capability of Enterprise Agent Coalition Based on Information Fusion and Attribute Reduction

    Institute of Scientific and Technical Information of China (English)

    Dongjun Liu; Li Li; and Jiayang Wang

    2016-01-01

    For the issue of evaluation of capability of enterprise agent coalition, an evaluation model based on information fusion and entropy weighting method is presented. The attribute reduction method is utilized to reduce indicators of the capability according to the theory of rough set. The new indicator system can be determined. Attribute reduction can also reduce the workload and remove the redundant information, when there are too many indicators or the indicators have strong correlation. The research complexity can be reduced and the efficiency can be improved. Entropy weighting method is used to determine the weights of the remaining indicators, and the importance of indicators is analyzed. The information fusion model based on nearest neighbor method is developed and utilized to evaluate the capability of multiple agent coalitions, compared to cloud evaluation model and D-S evidence method. Simulation results are reasonable and with obvious distinction. Thus they verify the effectiveness and feasibility of the model. The information fusion model can provide more scientific, rational decision support for choosing the best agent coalition, and provide innovative steps for the evaluation process of capability of agent coalitions.

  2. 面向软件Agent的“数字城市”组织模型研究%Research on Building Models of "Digital City" Based on Agent

    Institute of Scientific and Technical Information of China (English)

    王映辉; 周明全; 耿国华

    2001-01-01

    According to the distribution of "digital city",discuss it's data organization model. Classify the basic software-Agent of "digital city" for three kinds: data-Agent, medi-Agent and function-Agent.Describe inner structure of these three Agent, propose a organization model of "digital city" based on these three Agent, and give description of this model.

  3. Quantitative agent based model of user behavior in an Internet discussion forum.

    Directory of Open Access Journals (Sweden)

    Pawel Sobkowicz

    Full Text Available The paper presents an agent based simulation of opinion evolution, based on a nonlinear emotion/information/opinion (E/I/O individual dynamics, to an actual Internet discussion forum. The goal is to reproduce the results of two-year long observations and analyses of the user communication behavior and of the expressed opinions and emotions, via simulations using an agent based model. The model allowed to derive various characteristics of the forum, including the distribution of user activity and popularity (outdegree and indegree, the distribution of length of dialogs between the participants, their political sympathies and the emotional content and purpose of the comments. The parameters used in the model have intuitive meanings, and can be translated into psychological observables.

  4. Agent-Based Evacuation Model Incorporating Fire Scene and Building Geometry

    Institute of Scientific and Technical Information of China (English)

    TANG Fangqin; REN Aizhu

    2008-01-01

    A comprehensive description of the key factors affecting evacuations at fire scones is necessary for accurate simulations.An agent-based simulation model which incorporates the fire scene and the building geometry is developed using a fire dynamics simulator (FDS) based on the computational fluid dynamics and geographic information system (GIS) data to model the occupant response.The building entities are generated for FDS simulation while the spatial analysis on GIS data represents the occupant's knowledge of the building.The influence of the fire is based on a hazard assessment of the combustion products.The agent behavior and decisions are affected by environmental features and the fire field.A case study demonstrates that the evacuation model effectively simulates the coexistence and interactions of the major factors including occupants,building geometry,and fire disaster during the evacuation.The results can be used for the assessments of building designs regarding fire safety.

  5. Study of the attractor structure of an agent-based sociological model

    International Nuclear Information System (INIS)

    The Sznajd model is a sociophysics model that is based in the Potts model, and used for describing opinion propagation in a society. It employs an agent-based approach and interaction rules favouring pairs of agreeing agents. It has been successfully employed in modeling some properties and scale features of both proportional and majority elections (see for instance the works of A. T. Bernardes and R. N. Costa Filho), but its stationary states are always consensus states. In order to explain more complicated behaviours, we have modified the bounded confidence idea (introduced before in other opinion models, like the Deffuant model), with the introduction of prejudices and biases (we called this modification confidence rules), and have adapted it to the discrete Sznajd model. This generalized Sznajd model is able to reproduce almost all of the previous versions of the Sznajd model, by using appropriate choices of parameters. We solved the attractor structure of the resulting model in a mean-field approach and made Monte Carlo simulations in a Barabasi-Albert network. These simulations show great similarities with the mean-field, for the tested cases of 3 and 4 opinions. The dynamical systems approach that we devised allows for a deeper understanding of the potential of the Sznajd model as an opinion propagation model and can be easily extended to other models, like the voter model. Our modification of the bounded confidence rule can also be readily applied to other opinion propagation models.

  6. Study of the attractor structure of an agent-based sociological model

    Energy Technology Data Exchange (ETDEWEB)

    Timpanaro, Andre M; Prado, Carmen P C, E-mail: timpa@if.usp.br, E-mail: prado@if.usp.br [Instituto de Fisica da Universidade de Sao Paulo, Sao Paulo (Brazil)

    2011-03-01

    The Sznajd model is a sociophysics model that is based in the Potts model, and used for describing opinion propagation in a society. It employs an agent-based approach and interaction rules favouring pairs of agreeing agents. It has been successfully employed in modeling some properties and scale features of both proportional and majority elections (see for instance the works of A. T. Bernardes and R. N. Costa Filho), but its stationary states are always consensus states. In order to explain more complicated behaviours, we have modified the bounded confidence idea (introduced before in other opinion models, like the Deffuant model), with the introduction of prejudices and biases (we called this modification confidence rules), and have adapted it to the discrete Sznajd model. This generalized Sznajd model is able to reproduce almost all of the previous versions of the Sznajd model, by using appropriate choices of parameters. We solved the attractor structure of the resulting model in a mean-field approach and made Monte Carlo simulations in a Barabasi-Albert network. These simulations show great similarities with the mean-field, for the tested cases of 3 and 4 opinions. The dynamical systems approach that we devised allows for a deeper understanding of the potential of the Sznajd model as an opinion propagation model and can be easily extended to other models, like the voter model. Our modification of the bounded confidence rule can also be readily applied to other opinion propagation models.

  7. Agent-based modeling: a new approach for theory building in social psychology.

    Science.gov (United States)

    Smith, Eliot R; Conrey, Frederica R

    2007-02-01

    Most social and psychological phenomena occur not as the result of isolated decisions by individuals but rather as the result of repeated interactions between multiple individuals over time. Yet the theory-building and modeling techniques most commonly used in social psychology are less than ideal for understanding such dynamic and interactive processes. This article describes an alternative approach to theory building, agent-based modeling (ABM), which involves simulation of large numbers of autonomous agents that interact with each other and with a simulated environment and the observation of emergent patterns from their interactions. The authors believe that the ABM approach is better able than prevailing approaches in the field, variable-based modeling (VBM) techniques such as causal modeling, to capture types of complex, dynamic, interactive processes so important in the social world. The article elaborates several important contrasts between ABM and VBM and offers specific recommendations for learning more and applying the ABM approach. PMID:18453457

  8. Agent Based Trust Management Model Based on Weight Value Model for Online Auctions

    Directory of Open Access Journals (Sweden)

    E.Sathiyamoorthy

    2009-10-01

    Full Text Available This paper is aimed at the stipulations which arise in the traditional online auctions as a result of various anomalies in the reputation and trust calculation mechanism. We try to improve the scalability andefficiency of the online auctions by providing efficient trust management methodology considering several factors into consideration. A comparison between the performance of the auctions system with and without the agent methodology is done with good results.

  9. Variance in system dynamics and agent based modelling using the SIR model of infectious diseases

    OpenAIRE

    Ahmed, Aslam; Greensmith, Julie; Aickelin, Uwe

    2012-01-01

    Classical deterministic simulations of epidemiological processes, such as those based on System Dynamics, produce a single result based on a fixed set of input parameters with no variance between simulations. Input parameters are subsequently modified on these simulations using Monte-Carlo methods, to understand how changes in the input parameters affect the spread of results for the simulation. Agent Based simulations are able to produce different output results on each run based on knowledg...

  10. Electricity Market Games: How Agent-Based Modeling Can Help under High Penetrations of Variable Generation

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, Giulia

    2016-03-01

    Integrating increasingly high levels of variable generation in U.S. electricity markets requires addressing not only power system and grid modeling challenges but also an understanding of how market participants react and adapt to them. Key elements of current and future wholesale power markets can be modeled using an agent-based approach, which may prove to be a useful paradigm for researchers studying and planning for power systems of the future.

  11. An Evolutionary Agent-based simulation model for the industry life cycle

    OpenAIRE

    Lehmann-Waffenschmidt, B. Cornelia

    2008-01-01

    In contrast to the usual approach taken in the literature, in which an Industry Life Cycle (ILC) is reproduced by aggregate functions, the model of this paper generates a self-organizing ILC. A general evolutionary agent-based simulation model is developed that can be adapted for specific branches of industry. The results enable conclusions to be drawn for competition policy with regard to the workability of competition in the various phases of the ILC.

  12. Asking the Oracle: Introducing Forecasting Principles into Agent-Based Modelling

    OpenAIRE

    Hassan, Samer; Arroyo, Javier; Galán Ordax, José Manuel; Antunes, Luis; Pavón Mestras, Juan

    2013-01-01

    This paper presents a set of guidelines, imported from the field of forecasting, that can help social simulation and, more specifically, agent-based modelling practitioners to improve the predictive performance and the robustness of their models. The presentation starts with a discussion on the current debate on prediction in social processes, followed by an overview of the recent experience and lessons learnt from the field of forecasting. This is the basis to define standard practices when ...

  13. Citizenship and Power in an Agent-based Model of Tax Compliance with Public Expenditure

    OpenAIRE

    Paolo Pellizzari; Dino Rizzi

    2012-01-01

    In this paper we present a model of tax compliance with heterogeneous agents who maximize their individual utility based on income and the conjectured level of per capita public expenditure. We formally include psychological drivers in this model. These drivers affect individual behavior, such as risk aversion, together with appreciation of public expenditure, expectations about peers� compliance and a natural inclination to comply, all of which we summarize in a quality termed �citizenship�....

  14. Agent-based modelling as scientific method: a case study analysing primate social behaviour

    OpenAIRE

    Bryson, Joanna J.; Ando, Yasushi; Lehmann, Hagen

    2007-01-01

    A scientific methodology in general should provide two things: first, a means of explanation and, second, a mechanism for improving that explanation. Agent-based modelling (ABM) is a method that facilitates exploring the collective effects of individual action selection. The explanatory force of the model is the extent to which an observed meta-level phenomenon can be accounted for by the behaviour of its micro-level actors. This article demonstrates that this methodology can be applied to th...

  15. An agent-based approach for modeling dynamics of contagious disease spread

    OpenAIRE

    Dragicevic Suzana; Perez Liliana

    2009-01-01

    Abstract Background The propagation of communicable diseases through a population is an inherent spatial and temporal process of great importance for modern society. For this reason a spatially explicit epidemiologic model of infectious disease is proposed for a greater understanding of the disease's spatial diffusion through a network of human contacts. Objective The objective of this study is to develop an agent-based modelling approach the integrates geographic information systems (GIS) to...

  16. Agent-based model of laser hair removal: A treatment optimization and patient education tool

    Directory of Open Access Journals (Sweden)

    Eapen Bell

    2009-01-01

    Full Text Available Background: Tracking of various parameters associated with laser hair removal is tedious and time consuming. The currently available mathematical models are not simple enough for physicians to be used as a treatment optimization and patient education tool. Aim: The aim of the study was to develop a mathematical model for laser hair removal using agent-based modeling and to make a user-friendly simulation environment. Methods: The model was created using NetLogo. The hairs were modeled as agents oscillating between anagen and telogen. The variables were assigned based on published data whenever possible and the various paths the agent could take were coded as conditional statements. The improvement was assessed using an arbitrary index which takes into account the mean diameter and pigmentation along with the number and length of hairs visible above the surface. Few of the commonly encountered scenarios were simulated using the model. Results: The model is made freely available online (http://www.gulfdoctor.net/model/lhr.htm. Limited number of simulations performed indicated that an eight-week gap between laser sessions may be more effective than a four-week gap. Conclusions: The simulation provides a reliable tool for treatment optimization and patient education as obtaining relevant clinical data is slow and labor-intensive. Its visual interface and online availability makes it useful for everyday use.

  17. Re-Examining of Moffitt's Theory of Delinquency through Agent Based Modeling.

    Directory of Open Access Journals (Sweden)

    Jia Ning Leaw

    Full Text Available Moffitt's theory of delinquency suggests that at-risk youths can be divided into two groups, the adolescence- limited group and the life-course-persistent group, predetermined at a young age, and social interactions between these two groups become important during the adolescent years. We built an agent-based model based on the microscopic interactions Moffitt described: (i a maturity gap that dictates (ii the cost and reward of antisocial behavior, and (iii agents imitating the antisocial behaviors of others more successful than themselves, to find indeed the two groups emerging in our simulations. Moreover, through an intervention simulation where we moved selected agents from one social network to another, we also found that the social network plays an important role in shaping the life course outcome.

  18. Intelligent Agent Based Model for Auction Service Discovery in Mobile E-Commerce

    OpenAIRE

    Nandini S Sidnal; Manvi, Sunilkumar S

    2012-01-01

    Internet enabled auctions are one of the popular application which basically require a web service discovery mechanism that is efficient in all perspectives. This paper focuses on auction service discovery and building repository of services for the use of E-customers. The auction service directory (repository) is developed based on the customer’s desires. Agent based Belief Desire Intention (BDI) architecture is used in this model, not only to support the service discovery process in spott...

  19. Learning models of intelligent agents

    Energy Technology Data Exchange (ETDEWEB)

    Carmel, D.; Markovitch, S. [Computer Science Dept., Haifa (Israel)

    1996-12-31

    Agents that operate in a multi-agent system need an efficient strategy to handle their encounters with other agents involved. Searching for an optimal interactive strategy is a hard problem because it depends mostly on the behavior of the others. In this work, interaction among agents is represented as a repeated two-player game, where the agents` objective is to look for a strategy that maximizes their expected sum of rewards in the game. We assume that agents` strategies can be modeled as finite automata. A model-based approach is presented as a possible method for learning an effective interactive strategy. First, we describe how an agent should find an optimal strategy against a given model. Second, we present an unsupervised algorithm that infers a model of the opponent`s automaton from its input/output behavior. A set of experiments that show the potential merit of the algorithm is reported as well.

  20. On Mechanism, Process and Polity: An Agent-Based Modeling and Simulation Approach

    Directory of Open Access Journals (Sweden)

    Camelia Florela Voinea

    2014-07-01

    Full Text Available The present approach provides a theoretical account of political culture-based modeling of political change phenomena. Our approach is an agent-based simulation model inspired by a social-psychological account of the relation between the individual agents (citizens and the polity. It includes political culture as a fundamental modeling dimension. On this background, we reconsider the operational definitions of agent, mechanism, process, and polity so as to specify the role they play in the modeling of political change phenomena. We evaluate our previous experimental simulation experience in corruption emergence and political attitude change. The paper approaches the artificial polity as a political culture-based model of a body politic. It involves political culture concepts to account for the complexity of domestic political phenomena, going from political attitude change at the individual level up to major political change at the societal level. Architecture, structure, unit of interaction, generative mechanisms and processes are described. Both conceptual and experimental issues are described so as to highlight the differences between the simulation models of society and polity.

  1. An Agent-Based Modeling Template for a Cohort of Veterans with Diabetic Retinopathy.

    Directory of Open Access Journals (Sweden)

    Theodore Eugene Day

    Full Text Available Agent-based models are valuable for examining systems where large numbers of discrete individuals interact with each other, or with some environment. Diabetic Veterans seeking eye care at a Veterans Administration hospital represent one such cohort.The objective of this study was to develop an agent-based template to be used as a model for a patient with diabetic retinopathy (DR. This template may be replicated arbitrarily many times in order to generate a large cohort which is representative of a real-world population, upon which in-silico experimentation may be conducted.Agent-based template development was performed in java-based computer simulation suite AnyLogic Professional 6.6. The model was informed by medical data abstracted from 535 patient records representing a retrospective cohort of current patients of the VA St. Louis Healthcare System Eye clinic. Logistic regression was performed to determine the predictors associated with advancing stages of DR. Predicted probabilities obtained from logistic regression were used to generate the stage of DR in the simulated cohort.The simulated cohort of DR patients exhibited no significant deviation from the test population of real-world patients in proportion of stage of DR, duration of diabetes mellitus (DM, or the other abstracted predictors. Simulated patients after 10 years were significantly more likely to exhibit proliferative DR (P<0.001.Agent-based modeling is an emerging platform, capable of simulating large cohorts of individuals based on manageable data abstraction efforts. The modeling method described may be useful in simulating many different conditions where course of disease is described in categorical stages.

  2. Graceful Failure and Societal Resilience Analysis Via Agent-Based Modeling and Simulation

    Science.gov (United States)

    Schopf, P. S.; Cioffi-Revilla, C.; Rogers, J. D.; Bassett, J.; Hailegiorgis, A. B.

    2014-12-01

    Agent-based social modeling is opening up new methodologies for the study of societal response to weather and climate hazards, and providing measures of resiliency that can be studied in many contexts, particularly in coupled human and natural-technological systems (CHANTS). Since CHANTS are complex adaptive systems, societal resiliency may or may not occur, depending on dynamics that lack closed form solutions. Agent-based modeling has been shown to provide a viable theoretical and methodological approach for analyzing and understanding disasters and societal resiliency in CHANTS. Our approach advances the science of societal resilience through computational modeling and simulation methods that complement earlier statistical and mathematical approaches. We present three case studies of social dynamics modeling that demonstrate the use of these agent based models. In Central Asia, we exmaine mutltiple ensemble simulations with varying climate statistics to see how droughts and zuds affect populations, transmission of wealth across generations, and the overall structure of the social system. In Eastern Africa, we explore how successive episodes of drought events affect the adaptive capacity of rural households. Human displacement, mainly, rural to urban migration, and livelihood transition particularly from pastoral to farming are observed as rural households interacting dynamically with the biophysical environment and continually adjust their behavior to accommodate changes in climate. In the far north case we demonstrate one of the first successful attempts to model the complete climate-permafrost-infrastructure-societal interaction network as a complex adaptive system/CHANTS implemented as a ``federated'' agent-based model using evolutionary computation. Analysis of population changes resulting from extreme weather across these and other cases provides evidence for the emergence of new steady states and shifting patterns of resilience.

  3. Mesoscopic effects in an agent-based bargaining model in regular lattices.

    Science.gov (United States)

    Poza, David J; Santos, José I; Galán, José M; López-Paredes, Adolfo

    2011-01-01

    The effect of spatial structure has been proved very relevant in repeated games. In this work we propose an agent based model where a fixed finite population of tagged agents play iteratively the Nash demand game in a regular lattice. The model extends the multiagent bargaining model by Axtell, Epstein and Young modifying the assumption of global interaction. Each agent is endowed with a memory and plays the best reply against the opponent's most frequent demand. We focus our analysis on the transient dynamics of the system, studying by computer simulation the set of states in which the system spends a considerable fraction of the time. The results show that all the possible persistent regimes in the global interaction model can also be observed in this spatial version. We also find that the mesoscopic properties of the interaction networks that the spatial distribution induces in the model have a significant impact on the diffusion of strategies, and can lead to new persistent regimes different from those found in previous research. In particular, community structure in the intratype interaction networks may cause that communities reach different persistent regimes as a consequence of the hindering diffusion effect of fluctuating agents at their borders. PMID:21408019

  4. A critical survey of agent-based wholesale electricity market models

    International Nuclear Information System (INIS)

    The complexity of electricity markets calls for rich and flexible modeling techniques that help to understand market dynamics and to derive advice for the design of appropriate regulatory frameworks. Agent-Based Computational Economics (ACE) is a fairly young research paradigm that offers methods for realistic electricity market modeling. A growing number of researchers have developed agent-based models for simulating electricity markets. The diversity of approaches makes it difficult to overview the field of ACE electricity research; this literature survey should guide the way through and describe the state-of-the-art of this research area. In a conclusive summary, shortcomings of existing approaches and open issues that should be addressed by ACE electricity researchers are critically discussed. (author)

  5. Effects of Heterogeneity in Residential Preferences on an Agent-Based Model of Urban Sprawl

    Directory of Open Access Journals (Sweden)

    Derek T. Robinson

    2006-06-01

    Full Text Available The ability of agent-based models (ABMs to represent heterogeneity in the characteristics and behaviors of actors enables analyses about the implications of this heterogeneity for system behavior. The importance of heterogeneity in the specification of ABMs, however, creates new demands for empirical support. An earlier analysis of a survey of residential preferences within southeastern Michigan revealed seven groups of residents with similar preferences on similar characteristics of location. In this paper, we present an ABM that represents the process of residential development within an urban system and run it for a hypothetical pattern of environmental variation. Residential locations are selected by residential agents, who evaluate locations on the basis of preference for nearness to urban services, including jobs, aesthetic quality of the landscape, and their similarity to their neighbors. We populate our ABM with a population of residential preferences drawn from the survey results in five different ways: (1 preferences drawn at random; (2 equal preferences based on the mean from the entire survey sample; (3 preferences drawn from a single distribution, whose mean and standard deviation are derived from the survey sample; (4 equal preferences within each of seven groups, based on the group means; and (5 preferences drawn from distributions for each of seven groups, defined by group means and standard deviations. Model sensitivity analysis, based on multiple runs of our model under each case, revealed that adding heterogeneity to agents has a significant effect on model outcomes, measured by aggregate patterns of development sprawl and clustering.

  6. Bridging the gap: From computational agent-based models to analytical tractability

    Science.gov (United States)

    Dyson, Louise; Lafuerza, Luis F.; McKane, Alan J.; Edmonds, Bruce

    2014-03-01

    In order to investigate complex inter-dependent systems such as those found in the biological and social sciences, one is often left trying to examine complicated, descriptive models. To aid in understanding these it would be helpful to develop tools for examining how these relate to simpler models with understandable and analysable mechanisms. We describe a way of analysing the formation of a social network in a complex computational model that represents voting patterns in a population of agents who may live, work and form friendships together. Once the network is formed, we examine the spread of ``intention to vote'' and compare our findings with those found in the descriptive, agent-based model.

  7. An Agent-Based Model of Farmer Decision Making in Jordan

    Science.gov (United States)

    Selby, Philip; Medellin-Azuara, Josue; Harou, Julien; Klassert, Christian; Yoon, Jim

    2016-04-01

    We describe an agent based hydro-economic model of groundwater irrigated agriculture in the Jordan Highlands. The model employs a Multi-Agent-Simulation (MAS) framework and is designed to evaluate direct and indirect outcomes of climate change scenarios and policy interventions on farmer decision making, including annual land use, groundwater use for irrigation, and water sales to a water tanker market. Land use and water use decisions are simulated for groups of farms grouped by location and their behavioural and economic similarities. Decreasing groundwater levels, and the associated increase in pumping costs, are important drivers for change within Jordan'S agricultural sector. We describe how this is considered by coupling of agricultural and groundwater models. The agricultural production model employs Positive Mathematical Programming (PMP), a method for calibrating agricultural production functions to observed planted areas. PMP has successfully been used with disaggregate models for policy analysis. We adapt the PMP approach to allow explicit evaluation of the impact of pumping costs, groundwater purchase fees and a water tanker market. The work demonstrates the applicability of agent-based agricultural decision making assessment in the Jordan Highlands and its integration with agricultural model calibration methods. The proposed approach is designed and implemented with software such that it could be used to evaluate a variety of physical and human influences on decision making in agricultural water management.

  8. A Harris-Todaro Agent-Based Model to Rural-Urban Migration

    CERN Document Server

    Espindola, A L; Silveira, J J; Espindola, Aquino L.; Silveira, Jaylson J.

    2005-01-01

    The Harris-Todaro model of the rural-urban migration process is revisited under an agent-based approach. The migration of the workers is interpreted as a process of social learning by imitation, formalized by a computational model. By simulating this model, we observe a transitional dynamics with continuous growth of the urban fraction of overall population toward an equilibrium. Such an equilibrium is characterized by stabilization of rural-urban expected wages differential (generalized Harris-Todaro equilibrium condition), urban concentration and urban unemployment. These classic results obtained originally by Harris and Todaro are emergent properties of our model.

  9. Building v/s Exploring Models: Comparing Learning of Evolutionary Processes through Agent-based Modeling

    Science.gov (United States)

    Wagh, Aditi

    Two strands of work motivate the three studies in this dissertation. Evolutionary change can be viewed as a computational complex system in which a small set of rules operating at the individual level result in different population level outcomes under different conditions. Extensive research has documented students' difficulties with learning about evolutionary change (Rosengren et al., 2012), particularly in terms of levels slippage (Wilensky & Resnick, 1999). Second, though building and using computational models is becoming increasingly common in K-12 science education, we know little about how these two modalities compare. This dissertation adopts agent-based modeling as a representational system to compare these modalities in the conceptual context of micro-evolutionary processes. Drawing on interviews, Study 1 examines middle-school students' productive ways of reasoning about micro-evolutionary processes to find that the specific framing of traits plays a key role in whether slippage explanations are cued. Study 2, which was conducted in 2 schools with about 150 students, forms the crux of the dissertation. It compares learning processes and outcomes when students build their own models or explore a pre-built model. Analysis of Camtasia videos of student pairs reveals that builders' and explorers' ways of accessing rules, and sense-making of observed trends are of a different character. Builders notice rules through available blocks-based primitives, often bypassing their enactment while explorers attend to rules primarily through the enactment. Moreover, builders' sense-making of observed trends is more rule-driven while explorers' is more enactment-driven. Pre and posttests reveal that builders manifest a greater facility with accessing rules, providing explanations manifesting targeted assembly. Explorers use rules to construct explanations manifesting non-targeted assembly. Interviews reveal varying degrees of shifts away from slippage in both

  10. Agent-based modeling of the energy network for hybrid cars

    International Nuclear Information System (INIS)

    Highlights: • An approach to represent and calculate multicarrier energy networks has been developed. • It provides a modeling method based on agents, for multicarrier energy networks. • It allows the system representation on a single sheet. • Energy flows circulating in the system can be observed dynamically during simulation. • The method is technology independent. - Abstract: Studies in complex energy networks devoted to the modeling of electrical power grids, were extended in previous work, where a computational multi-layered ontology, implemented using agent-based methods, was adopted. This structure is compatible with recently introduced Multiplex Networks which using Multi-linear Algebra generalize some of classical results for single-layer networks, to multilayer networks in steady state. Static results do not assist overly in understanding dynamic networks in which the values of the variables in the nodes and edges can change suddenly, driven by events, and even where new nodes or edges may appear or disappear, also because of other events. To address this gap, a computational agent-based model is developed to extend the multi-layer and multiplex approaches. In order to demonstrate the benefits of a dynamical extension, a model of the energy network in a hybrid car is presented as a case study

  11. An agent-based model to study market penetration of plug-in hybrid electric vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Eppstein, Margaret J., E-mail: Maggie.Eppstein@uvm.edu [Department of Computer Science, University of Vermont, Burlington, VT 05405 (United States); Grover, David K.; Marshall, Jeffrey S.; Rizzo, Donna M. [School of Engineering, University of Vermont, Burlington, VT 05405 (United States)

    2011-06-15

    A spatially explicit agent-based vehicle consumer choice model is developed to explore sensitivities and nonlinear interactions between various potential influences on plug-in hybrid vehicle (PHEV) market penetration. The model accounts for spatial and social effects (including threshold effects, homophily, and conformity) and media influences. Preliminary simulations demonstrate how such a model could be used to identify nonlinear interactions among potential leverage points, inform policies affecting PHEV market penetration, and help identify future data collection necessary to more accurately model the system. We examine sensitivity of the model to gasoline prices, to accuracy in estimation of fuel costs, to agent willingness to adopt the PHEV technology, to PHEV purchase price and rebates, to PHEV battery range, and to heuristic values related to gasoline usage. Our simulations indicate that PHEV market penetration could be enhanced significantly by providing consumers with ready estimates of expected lifetime fuel costs associated with different vehicles (e.g., on vehicle stickers), and that increases in gasoline prices could nonlinearly magnify the impact on fleet efficiency. We also infer that a potential synergy from a gasoline tax with proceeds is used to fund research into longer-range lower-cost PHEV batteries. - Highlights: > We model consumer agents to study potential market penetration of PHEVs. > The model accounts for spatial, social, and media effects. > We identify interactions among potential leverage points that could inform policy. > Consumer access to expected lifetime fuel costs may enhance PHEV market penetration. > Increasing PHEV battery range has synergistic effects on fleet efficiency.

  12. Dynamics of bloggers’ communities: Bipartite networks from empirical data and agent-based modeling

    Science.gov (United States)

    Mitrović, Marija; Tadić, Bosiljka

    2012-11-01

    We present an analysis of the empirical data and the agent-based modeling of the emotional behavior of users on the Web portals where the user interaction is mediated by posted comments, like Blogs and Diggs. We consider the dataset of discussion-driven popular Diggs, in which all comments are screened by machine-learning emotion detection in the text, to determine positive and negative valence (attractiveness and aversiveness) of each comment. By mapping the data onto a suitable bipartite network, we perform an analysis of the network topology and the related time-series of the emotional comments. The agent-based model is then introduced to simulate the dynamics and to capture the emergence of the emotional behaviors and communities. The agents are linked to posts on a bipartite network, whose structure evolves through their actions on the posts. The emotional states (arousal and valence) of each agent fluctuate in time, subject to the current contents of the posts to which the agent is exposed. By an agent’s action on a post its current emotions are transferred to the post. The model rules and the key parameters are inferred from the considered empirical data to ensure their realistic values and mutual consistency. The model assumes that the emotional arousal over posts drives the agent’s action. The simulations are preformed for the case of constant flux of agents and the results are analyzed in full analogy with the empirical data. The main conclusions are that the emotion-driven dynamics leads to long-range temporal correlations and emergent networks with community structure, that are comparable with the ones in the empirical system of popular posts. In view of pure emotion-driven agents actions, this type of comparisons provide a quantitative measure for the role of emotions in the dynamics on real blogs. Furthermore, the model reveals the underlying mechanisms which relate the post popularity with the emotion dynamics and the prevalence of negative

  13. Agent-based and macroscopic modeling of the complex socio-economic systems

    CERN Document Server

    Kononovicius, Aleksejus

    2013-01-01

    The current economic crisis has provoked an active response from the interdisciplinary scientific community. As a result many papers suggesting what can be improved in understanding of the complex socio-economics systems were published. Some of the most prominent papers on the topic include (Bouchaud, 2009; Farmer and Foley, 2009; Farmer et al, 2012; Helbing, 2010; Pietronero, 2008). These papers share the idea that agent-based modeling is essential for the better understanding of the complex socio-economic systems and consequently better policy making. Yet in order for an agent-based model to be useful it should also be analytically tractable, possess a macroscopic treatment (Cristelli et al, 2012). In this work we shed a new light on our research group's contributions towards understanding of the correspondence between the inter-individual interactions and collective behavior. We also provide some new insights into the implications of the global and local interactions, the leadership and the predator-prey i...

  14. 基于HLA的Agent-DEVS协同仿真建模%Collaborative modeling and simulation of Agent-DEVS based on HLA

    Institute of Scientific and Technical Information of China (English)

    曹琦; 何中市; 余磊

    2011-01-01

    In order to extend the DEVS with abilities of intelligent modeling and distributed simulation, a collaborative modeling and simulation method for Agent-DEVS based on HLA was studied. The formal description of Agent-DEVS federate models based on ParalIeI-DEVS was proposed. The models ports in Agent-DEVS were translated into data objects in HLA and the structure of the models was given. The communication mechanism was analyzed. The mapping between knowledge update in Agent-DEVS and attribute update in HLA, and that between models coupling in Agent-DEVS and instances interaction in HLA, were established respectively. Finally, the modeling and simulation application for material supply in emergent disaster was put forward. The results show that the reusability of Agent-DEVS models is enhanced by HLA and the interoperability of the models is enriched by knowledge update mechanism. In addition, the autonomy and independent ability for transaction processing are improved significantly.%为实现DEVS在智能建模与分布仿真能力方面的扩充,研究了基于HLA的Agent-DEVS协同仿真建模方法.以并行DEVS为基础,提出了Agent-DEVS联邦模型的形式化描述;将Agent-DEVS模型端口转换为HLA数据对象,确定了Agent-DEVS联邦模型结构,并分析了通信机制,分别建立了Agent-DEVS的知识更新与HLA的属性更新间的映射,以及Agent-DEVS的模型耦合与HLA的实例交互间的映射;最后结合抢险救灾物资保障的仿真建模进行了应用.结果表明,HLA体系框架增强了Agent-DEVS模型的可重用性;知识更新机制丰富了Agent-DEVS模型的互操作性;同时,Agent-DEVS模型的自治性与独立事务处理能力得到了进一步提高.

  15. Tele-Immersive Interaction with Intelligent Virtual Agents Based on Real-Time 3D Modeling

    Directory of Open Access Journals (Sweden)

    Shujun Zhang

    2012-02-01

    Full Text Available To enable intelligent agents interacting smoothly with human users, researchers have been deploying novel interaction modalities (e.g. non-verbal cue, vision and touch in addition to agents’ conversational skills. Models of multi-modality interaction can enhance agents’ real-time perception, cognition and reaction towards the user. In this paper we report a novel tele-immersive interaction system developed using real-time 3D modelling techniques. In such system user’s full body is reconstructed using multi-view cameras and CUDA based visual hull reconstruction algorithm. User’s mesh model is then loaded into a virtual environment for interacting with an autonomous agent. Technical details and initial results of the system are illustrated in this paper. Following that a novel interaction scenario is proposed which links the virtual agent with a remote physical robot who takes the role of mediating interactions between two geographically separated users. Finally we discuss in depth the implications of such human-agent interaction and possible future improvements and directions.

  16. An agent-based model to rural-urban migration analysis

    CERN Document Server

    Silveira, J J; Penna, T J P; Silveira, Jaylson J.; Espindola, Aquino L.

    2005-01-01

    In this paper we analyze the rural-urban migration phenomena as it is usually observed in economies which are in the early stages of industrialization. The analysis is conducted by means of a statistical mechanics approach which builds a computational agent-based model. Agents are placed on a lattice and the connections among them are described via an Ising like model. Simulations on this computational model show some emergent properties that are common in developing economies, such as a transitional dynamics characterized by continuous growth of urban population, followed by the equalization of expected wages between rural and urban sectors (Harris-Todaro equilibrium condition), urban concentration and increasing of per capita income.

  17. Evaluating agri-environmental schemes using a spatially explicit agent-based modelling approach

    OpenAIRE

    Schouten, M.A.H.; Polman, N.B.P.; Westerhof, E.J.G.M.; Opdam, P.F.M.

    2012-01-01

    Networks of nature reserves are being proposed as a solution when the degree of fragmentation is considered to endanger the long-term persistence of species diversity. Agri-environmental schemes are supposed to make a positive contribution to these networks. The spatially explicit agent-based model presented in this chapter combines spatial dynamics in land ownership, land use and the importance of agri-environmental schemes in conserving biodiversity by capturing the heterogeneity of individ...

  18. Firms, Innovation, Export and the Policy Regime: An Agent-based model of the Defence Industry

    OpenAIRE

    2011-01-01

    The defence industry has traditionally been a heavily regulated and protected market. A new EU Directive being implemented in Norway, January 2012, intends to reform the European defence market towards a higher degree of openness and liberalization. It is therefore vital for the Norwegian Government and national defence authorities to explore the impacts this new EU Directive will have in the near future. This thesis presents a computational agent-based model of the Norwegian defence industry...

  19. Encouraging Sustainable Transport Choices in American Households: Results from an Empirically Grounded Agent-Based Model

    OpenAIRE

    Davide Natalini; Giangiacomo Bravo

    2013-01-01

    The transport sector needs to go through an extended process of decarbonisation to counter the threat of climate change. Unfortunately, the International Energy Agency forecasts an enormous growth in the number of cars and greenhouse gas emissions by 2050. Two issues can thus be identified: (1) the need for a new methodology that could evaluate the policy performances ex-ante and (2) the need for more effective policies. To help address these issues, we developed an Agent-Based Model called ...

  20. An Agent-Based Model of Sustainable Corporate Social Responsibility Activities

    OpenAIRE

    Isamu Okada

    2011-01-01

    An agent-based model of firms and their stakeholders' economic actions was used to test the theoretical feasibility of sustainable corporate social responsibility activities. Corporate social responsibility has become important to many firms, but CSR activities tend to get less attention during busts than during boom times. The hypothesis tested is that the CSR activities of a firm are more economically rational if the economic actions of its stakeholders reflect the firm's level of CSR. Our ...

  1. Design and development of an agent-based model for business operations faced with flood disruption.

    OpenAIRE

    C. Li; Coates, G.

    2016-01-01

    Small and medium enterprises (SMEs) constitute a major component of the United Kingdom’s economy, accounting for 99.9% of all private sector businesses and approximately 47% of annual turnover in 2014 [1]. However, these companies can suffer significant financial losses as a consequence of a disruption to business operations, such as a flood event, due to their limited resources and lack of organizational plans. Agent-based modelling is recognized as one approach to enable complex problems in...

  2. Organizational ecology and population dynamics in politics : an agent-based model

    OpenAIRE

    Jung, Danielle Fitzpatrick

    2012-01-01

    Markets, networks and hierarchies are the three core forms of social organization. They recur at all levels of social interaction as solutions to problems of cooperation. Disparate actors---from states, to "dark'' actors like rebel groups, to voters---use these organizations to solve their cooperative problems. This dissertation uses a general agent-based model (ABM) to examine how organizations affect cooperation and welfare across several issues. Humans form organizations to enhance coopera...

  3. Agent-based Model of Agricultural Practices in Late Iron Age

    Czech Academy of Sciences Publication Activity Database

    Cimler, R.; Olševičová, K.; Machálek, T.; Danielisová, Alžběta

    Osaka : Osaka University, 2012 - (Inuiguchi, M.; Kusunoki, Y.; Seki, H.), s. 166-172 [Czech-Japan Seminar on Data Analysis and Decision Making under Uncertainty /15./. Osaka (JP), 24.09.2012-27.09.2012] R&D Projects: GA ČR GAP405/12/0926 Institutional research plan: CEZ:AV0Z80020508 Institutional support: RVO:67985912 Keywords : agent-based model * knowledge representation * social simulation * NetLogo Subject RIV: AC - Archeology, Anthropology, Ethnology

  4. SimCode: Agent-based Simulation Modelling of Open-Source Software Development

    OpenAIRE

    Jean-Michel Dalle; David, Paul A.

    2005-01-01

    We present an original modeling tool, which can be used to study the mechanisms by which free/libre and open source software developers’ code-writing efforts are allocated within open source projects. It is first described analytically in a discrete choice framework, and then simulated using agent-based experiments. Contributions are added sequentially to either existing modules, or to create new modules out of existing ones: as a consequence, the global emerging architecture forms a hierarch...

  5. Analyzing the Validity of Relationship Banking through Agent-based Modeling

    Science.gov (United States)

    Nishikido, Yukihito; Takahashi, Hiroshi

    This article analyzes the validity of relationship banking through agent-based modeling. In the analysis, we especially focus on the relationship between economic conditions and both lenders' and borrowers' behaviors. As a result of intensive experiments, we made the following interesting findings: (1) Relationship banking contributes to reducing bad loan; (2) relationship banking is more effective in enhancing the market growth compared to transaction banking, when borrowers' sales scale is large; (3) keener competition among lenders may bring inefficiency to the market.

  6. Friends Forever: Social Relationships with a Fuzzy Agent-Based Model

    OpenAIRE

    Hassan, Samer; Salgado, Mauricio; Pavon, Juan

    2008-01-01

    Sociological research shows that friendship and partner choice tend to reveal a bias toward social similarity. These relations are ruled by the so called “proximity principle” which states that the more similar two individuals are, the more likely they will become friends. However, proximity, similarity or friend- ship are concepts with blurred edges and grades of membership (acquaintances, friends, couples). Therefore, in order to model the friendship dynamics we work on an Agent-Based...

  7. Agent Based Modeling of Land Use Change: The Case of Shade Coffee in Mexico.

    OpenAIRE

    Marcos-Martinez, Raymundo

    2013-01-01

    This research focuses on addressing methodological issues that impact the performance of spatially explicit discrete choice agent-based land use models that are estimated with remotely sensed data. The empirical setting considers land use transitions between agroforests, perennial crops, grass and corn, and fallow lands during the period 1984 - 2006 in a Mexican coffee growing region in which relatively high deforestation rates were observed. As a starting point, a Mixed Conditional - Multino...

  8. An Agent-Based Model of Centralized Institutions, Social Network Technology, and Revolution

    OpenAIRE

    Makowsky, Michael D.; Jared Rubin

    2011-01-01

    Recent uprisings in the Arab world consist of individuals revealing vastly different preferences than were expressed prior to the uprisings. This paper sheds light on the general mechanisms underlying large-scale social and institutional change. We employ an agent-based model to test the impact of authority centralization and social network technology on preference revelation and falsification, social protest, and institutional change. We find that the amount of social and institutional chang...

  9. Developing a multiscale, multi-resolution agent-based brain tumor model by graphics processing units

    OpenAIRE

    Zhang Le; Jiang Beini; Wu Yukun; Strouthos Costas; Sun Phillip; Su Jing; Zhou Xiaobo

    2011-01-01

    Abstract Multiscale agent-based modeling (MABM) has been widely used to simulate Glioblastoma Multiforme (GBM) and its progression. At the intracellular level, the MABM approach employs a system of ordinary differential equations to describe quantitatively specific intracellular molecular pathways that determine phenotypic switches among cells (e.g. from migration to proliferation and vice versa). At the intercellular level, MABM describes cell-cell interactions by a discrete module. At the t...

  10. Reconstruction of prehistoric settlement network using agent-based model in NetLogo

    Czech Academy of Sciences Publication Activity Database

    Olševičová, K.; Procházka, J.; Danielisová, Alžběta

    Cham: Springer International Publishing, 2015 - (Bajo, J.), s. 165-175. (Communications in computer and information science . 524). ISBN 978-3-319-19033-4. [International workshops of PAAMS 2015. Salamanca (ES), 03.06.2015-04.06.2015] R&D Projects: GA ČR GAP405/12/0926 Institutional support: RVO:67985912 Keywords : agent-based model * archaeology * emergence * Netlogo * network Subject RIV: AC - Archeology, Anthropology, Ethnology http://www.springer.com/us/book/9783319190327

  11. Dosage and dose schedule screening of drug combinations in agent-based models reveals hidden synergies

    Directory of Open Access Journals (Sweden)

    Lisa Corina Barros de Andrade e Sousa1

    2016-01-01

    Full Text Available The fungus Candida albicans is the most common causative agent of human fungal infections and better drugs or drug combination strategies are urgently needed. Here, we present an agent-based model of the interplay of C. albicans with the host immune system and with the microflora of the host. We took into account the morphological change of C. albicans from the yeast to hyphae form and its dynamics during infection. The model allowed us to follow the dynamics of fungal growth and morphology, of the immune cells and of microflora in different perturbing situations. We specifically focused on the consequences of microflora reduction following antibiotic treatment. Using the agent-based model, different drug types have been tested for their effectiveness, namely drugs that inhibit cell division and drugs that constrain the yeast-to-hyphae transition. Applied individually, the division drug turned out to successfully decrease hyphae while the transition drug leads to a burst in hyphae after the end of the treatment. To evaluate the effect of different drug combinations, doses, and schedules, we introduced a measure for the return to a healthy state, the infection score. Using this measure, we found that the addition of a transition drug to a division drug treatment can improve the treatment reliability while minimizing treatment duration and drug dosage. In this work we present a theoretical study. Although our model has not been calibrated to quantitative experimental data, the technique of computationally identifying synergistic treatment combinations in an agent based model exemplifies the importance of computational techniques in translational research.

  12. Agent-based financial dynamics model from stochastic interacting epidemic system and complexity analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yunfan, E-mail: yunfanlu@yeah.net; Wang, Jun; Niu, Hongli

    2015-06-12

    An agent-based financial stock price model is developed and investigated by a stochastic interacting epidemic system, which is one of the statistical physics systems and has been used to model the spread of an epidemic or a forest fire. Numerical and statistical analysis are performed on the simulated returns of the proposed financial model. Complexity properties of the financial time series are explored by calculating the correlation dimension and using the modified multiscale entropy method. In order to verify the rationality of the financial model, the real stock market indexes, Shanghai Composite Index and Shenzhen Component Index, are studied in comparison with the simulation data of the proposed model for the different infectiousness parameters. The empirical research reveals that this financial model can reproduce some important features of the real stock markets. - Highlights: • A new agent-based financial price model is developed by stochastic interacting epidemic system. • The structure of the proposed model allows to simulate the financial dynamics. • Correlation dimension and MMSE are applied to complexity analysis of financial time series. • Empirical results show the rationality of the proposed financial model.

  13. Agent-based financial dynamics model from stochastic interacting epidemic system and complexity analysis

    International Nuclear Information System (INIS)

    An agent-based financial stock price model is developed and investigated by a stochastic interacting epidemic system, which is one of the statistical physics systems and has been used to model the spread of an epidemic or a forest fire. Numerical and statistical analysis are performed on the simulated returns of the proposed financial model. Complexity properties of the financial time series are explored by calculating the correlation dimension and using the modified multiscale entropy method. In order to verify the rationality of the financial model, the real stock market indexes, Shanghai Composite Index and Shenzhen Component Index, are studied in comparison with the simulation data of the proposed model for the different infectiousness parameters. The empirical research reveals that this financial model can reproduce some important features of the real stock markets. - Highlights: • A new agent-based financial price model is developed by stochastic interacting epidemic system. • The structure of the proposed model allows to simulate the financial dynamics. • Correlation dimension and MMSE are applied to complexity analysis of financial time series. • Empirical results show the rationality of the proposed financial model

  14. Agent-based modeling and simulation of clean heating system adoption in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Sopha, Bertha Maya

    2011-03-15

    A sound climate policy encouraging clean energy investment is important to mitigate global warming. Previous research has demonstrated that consumer choice indeed plays an important role in adoption of sustainable technologies. This thesis strives to gain a better understanding of consumers' decision-making on heating systems and to explore the potential application of agent-based modeling (ABM) in exploring mechanism underlying adoption in which heating system adoption by Norwegian households is taken up as a case study. An interdisciplinary approach, applying various established theories including those of psychology, is applied to create a model for consumer behavior and implement this behavior in an Agent-Based Model (ABM) to simulate heating technology diffusion. A mail-survey, carried out in autumn 2008, is a means to collect information for parameterizing the agent-based model, for gaining empirical facts, and for validating the developed model at micro-level. Survey sample consisted of 1500 Norwegian households drawn from population register and 1500 wood pellet users in Norway. The response rates were 10.3% and 34.6% for population sample and wood pellet sample respectively. This study is divided into two parts; empirical analysis and agent-based simulation. The empirical analysis aims at fully understanding the important aspects of adoption decision and their implications, in order to assist simulation. The analysis particularly contributes to the identification of differences/similarities between adopters and non adopters of wood pellet heating with respects to some key points of adoption derived from different theories, psychological factors underlying the adoption-decision of wood pellet heating, and the rationales underlying Norwegian households' decisions regarding their future heating system. The simulation study aims at exploring the mechanism of heterogeneous household decision-making giving rise to the diffusion of heating systems, and

  15. Simulating Transport and Land Use Interdependencies for Strategic Urban Planning—An Agent Based Modelling Approach

    Directory of Open Access Journals (Sweden)

    Nam Huynh

    2015-10-01

    Full Text Available Agent based modelling has been widely accepted as a promising tool for urban planning purposes thanks to its capability to provide sophisticated insights into the social behaviours and the interdependencies that characterise urban systems. In this paper, we report on an agent based model, called TransMob, which explicitly simulates the mutual dynamics between demographic evolution, transport demands, housing needs and the eventual change in the average satisfaction of the residents of an urban area. The ability to reproduce such dynamics is a unique feature that has not been found in many of the like agent based models in the literature. TransMob, is constituted by six major modules: synthetic population, perceived liveability, travel diary assignment, traffic micro-simulator, residential location choice, and travel mode choice. TransMob is used to simulate the dynamics of a metropolitan area in South East of Sydney, Australia, in 2006 and 2011, with demographic evolution. The results are favourably compared against survey data for the area in 2011, therefore validating the capability of TransMob to reproduce the observed complexity of an urban area. We also report on the application of TransMob to simulate various hypothetical scenarios of urban planning policies. We conclude with discussions on current limitations of TransMob, which serve as suggestions for future developments.

  16. Agent-Based Model to Study and Quantify the Evolution Dynamics of Android Malware Infection

    OpenAIRE

    Juan Alegre-Sanahuja; Javier Camacho; Juan Carlos Cortés López; Francisco-José Santonja; Rafael Jacinto Villanueva Micó

    2014-01-01

    In the last years the number of malware Apps that the users download to their devices has risen. In this paper, we propose an agent-based model to quantify the Android malware infection evolution, modeling the behavior of the users and the different markets where the users may download Apps. The model predicts the number of infected smartphones depending on the type of malware. Additionally, we will estimate the cost that the users should afford when the malware is in their devices. We will b...

  17. An agent-based computational model of the spread of tuberculosis

    International Nuclear Information System (INIS)

    In this work we propose an alternative model of the spread of tuberculosis (TB) and the emergence of drug resistance due to the treatment with antibiotics. We implement the simulations by an agent-based model computational approach where the spatial structure is taken into account. The spread of tuberculosis occurs according to probabilities defined by the interactions among individuals. The model was validated by reproducing results already known from the literature in which different treatment regimes yield the emergence of drug resistance. The different patterns of TB spread can be visualized at any time of the system evolution. The implementation details as well as some results of this alternative approach are discussed

  18. An integrated framework of agent-based modelling and robust optimization for microgrid energy management

    International Nuclear Information System (INIS)

    Highlights: • Microgrid composed of a train station, wind power plant and district is investigated. • Each player is modeled as an individual agent aiming at a particular goal. • Prediction Intervals quantify the uncertain operational and environmental parameters. • Optimal goal-directed actions planning is achieved with robust optimization. • Optimization framework improves system reliability and decreases power imbalances. - Abstract: A microgrid energy management framework for the optimization of individual objectives of microgrid stakeholders is proposed. The framework is exemplified by way of a microgrid that is connected to an external grid via a transformer and includes the following players: a middle-size train station with integrated photovoltaic power production system, a small energy production plant composed of urban wind turbines, and a surrounding district including residences and small businesses. The system is described by Agent-Based Modelling (ABM), in which each player is modelled as an individual agent aiming at a particular goal, (i) decreasing its expenses for power purchase or (ii) increasing its revenues from power selling. The context in which the agents operate is uncertain due to the stochasticity of operational and environmental parameters, and the technical failures of the renewable power generators. The uncertain operational and environmental parameters of the microgrid are quantified in terms of Prediction Intervals (PIs) by a Non-dominated Sorting Genetic Algorithm (NSGA-II) – trained Neural Network (NN). Under these uncertainties, each agent is seeking for optimal goal-directed actions planning by Robust Optimization (RO). The developed framework is shown to lead to an increase in system performance, evaluated in terms of typical reliability (adequacy) indicators for energy systems, such as Loss of Load Expectation (LOLE) and Loss of Expected Energy (LOEE), in comparison with optimal planning based on expected values of

  19. Investigating mathematical models of immuno-interactions with early-stage cancer under an agent-based modelling perspective

    OpenAIRE

    Figueredo, Grazziela P.; Siebers, Peer-Olaf; Aickelin, Uwe

    2013-01-01

    Many advances in research regarding immuno-interactions with cancer were developed with the help of ordinary differential equation (ODE) models. These models, however, are not effectively capable of representing problems involving individual localisation, memory and emerging properties, which are common characteristics of cells and molecules of the immune system. Agent-based modelling and simulation is an alternative paradigm to ODE models that overcomes these limitations. In this paper we in...

  20. An agent-based simulation model to study accountable care organizations.

    Science.gov (United States)

    Liu, Pai; Wu, Shinyi

    2016-03-01

    Creating accountable care organizations (ACOs) has been widely discussed as a strategy to control rapidly rising healthcare costs and improve quality of care; however, building an effective ACO is a complex process involving multiple stakeholders (payers, providers, patients) with their own interests. Also, implementation of an ACO is costly in terms of time and money. Immature design could cause safety hazards. Therefore, there is a need for analytical model-based decision-support tools that can predict the outcomes of different strategies to facilitate ACO design and implementation. In this study, an agent-based simulation model was developed to study ACOs that considers payers, healthcare providers, and patients as agents under the shared saving payment model of care for congestive heart failure (CHF), one of the most expensive causes of sometimes preventable hospitalizations. The agent-based simulation model has identified the critical determinants for the payment model design that can motivate provider behavior changes to achieve maximum financial and quality outcomes of an ACO. The results show nonlinear provider behavior change patterns corresponding to changes in payment model designs. The outcomes vary by providers with different quality or financial priorities, and are most sensitive to the cost-effectiveness of CHF interventions that an ACO implements. This study demonstrates an increasingly important method to construct a healthcare system analytics model that can help inform health policy and healthcare management decisions. The study also points out that the likely success of an ACO is interdependent with payment model design, provider characteristics, and cost and effectiveness of healthcare interventions. PMID:24715674

  1. Walk This Way: Improving Pedestrian Agent-Based Models through Scene Activity Analysis

    Directory of Open Access Journals (Sweden)

    Andrew Crooks

    2015-09-01

    Full Text Available Pedestrian movement is woven into the fabric of urban regions. With more people living in cities than ever before, there is an increased need to understand and model how pedestrians utilize and move through space for a variety of applications, ranging from urban planning and architecture to security. Pedestrian modeling has been traditionally faced with the challenge of collecting data to calibrate and validate such models of pedestrian movement. With the increased availability of mobility datasets from video surveillance and enhanced geolocation capabilities in consumer mobile devices we are now presented with the opportunity to change the way we build pedestrian models. Within this paper we explore the potential that such information offers for the improvement of agent-based pedestrian models. We introduce a Scene- and Activity-Aware Agent-Based Model (SA2-ABM, a method for harvesting scene activity information in the form of spatiotemporal trajectories, and incorporate this information into our models. In order to assess and evaluate the improvement offered by such information, we carry out a range of experiments using real-world datasets. We demonstrate that the use of real scene information allows us to better inform our model and enhance its predictive capabilities.

  2. Holistic flood risk assessment using agent-based modelling: the case of Sint Maarten Island

    Science.gov (United States)

    Abayneh Abebe, Yared; Vojinovic, Zoran; Nikolic, Igor; Hammond, Michael; Sanchez, Arlex; Pelling, Mark

    2015-04-01

    Floods in coastal regions are regarded as one of the most dangerous and harmful disasters. Though commonly referred to as natural disasters, coastal floods are also attributable to various social, economic, historical and political issues. Rapid urbanisation in coastal areas combined with climate change and poor governance can lead to a significant increase in the risk of pluvial flooding coinciding with fluvial and coastal flooding posing a greater risk of devastation in coastal communities. Disasters that can be triggered by hydro-meteorological events are interconnected and interrelated with both human activities and natural processes. They, therefore, require holistic approaches to help understand their complexity in order to design and develop adaptive risk management approaches that minimise social and economic losses and environmental impacts, and increase resilience to such events. Being located in the North Atlantic Ocean, Sint Maarten is frequently subjected to hurricanes. In addition, the stormwater catchments and streams on Sint Maarten have several unique characteristics that contribute to the severity of flood-related impacts. Urban environments are usually situated in low-lying areas, with little consideration for stormwater drainage, and as such are subject to flash flooding. Hence, Sint Maarten authorities drafted policies to minimise the risk of flood-related disasters on the island. In this study, an agent-based model is designed and applied to understand the implications of introduced policies and regulations, and to understand how different actors' behaviours influence the formation, propagation and accumulation of flood risk. The agent-based model built for this study is based on the MAIA meta-model, which helps to decompose, structure and conceptualize socio-technical systems with an agent-oriented perspective, and is developed using the NetLogo simulation environment. The agents described in this model are households and businesses, and

  3. Agent-based model of angiogenesis simulates capillary sprout initiation in multicellular networks.

    Science.gov (United States)

    Walpole, J; Chappell, J C; Cluceru, J G; Mac Gabhann, F; Bautch, V L; Peirce, S M

    2015-09-01

    Many biological processes are controlled by both deterministic and stochastic influences. However, efforts to model these systems often rely on either purely stochastic or purely rule-based methods. To better understand the balance between stochasticity and determinism in biological processes a computational approach that incorporates both influences may afford additional insight into underlying biological mechanisms that give rise to emergent system properties. We apply a combined approach to the simulation and study of angiogenesis, the growth of new blood vessels from existing networks. This complex multicellular process begins with selection of an initiating endothelial cell, or tip cell, which sprouts from the parent vessels in response to stimulation by exogenous cues. We have constructed an agent-based model of sprouting angiogenesis to evaluate endothelial cell sprout initiation frequency and location, and we have experimentally validated it using high-resolution time-lapse confocal microscopy. ABM simulations were then compared to a Monte Carlo model, revealing that purely stochastic simulations could not generate sprout locations as accurately as the rule-informed agent-based model. These findings support the use of rule-based approaches for modeling the complex mechanisms underlying sprouting angiogenesis over purely stochastic methods. PMID:26158406

  4. Effect of individual protective behaviors on influenza transmission: an agent-based model.

    Science.gov (United States)

    Karimi, Elnaz; Schmitt, Ketra; Akgunduz, Ali

    2015-09-01

    It is well established in the epidemiological literature that individual behaviors have a significant effect on the spread of infectious diseases. Agent-based models are increasingly being recognized as the next generation of epidemiological models. In this research, we use the ability of agent-based models to incorporate behavior into simulations by examining the relative importance of vaccination and social distancing, two common measures for controlling the spread of infectious diseases, with respect to seasonal influenza. We modeled health behaviour using the result of a Health Belief Model study focused on influenza. We considered a control and a treatment group to explore the effect of education on people's health-related behaviors patterns. The control group reflects the behavioral patterns of students based on their general knowledge of influenza and its interventions while the treatment group illustrates the level of behavioral changes after individuals have been educated by a health care expert. The results of this study indicate that self-initiated behaviors are successful in controlling an outbreak in a high contact rate location such as a university. Self-initiated behaviors resulted in a population attack rate decrease of 17% and a 25% reduction in the peak number of cases. The simulation also provides significant evidence for the effect of an HBM theory-based educational program to increase the rate of applying the target interventions (vaccination by 22% percent and social distancing by 41%) and consequently to control the outbreak. PMID:25578039

  5. Scopolamine provocation-based pharmacological MRI model for testing procognitive agents.

    Science.gov (United States)

    Hegedűs, Nikolett; Laszy, Judit; Gyertyán, István; Kocsis, Pál; Gajári, Dávid; Dávid, Szabolcs; Deli, Levente; Pozsgay, Zsófia; Tihanyi, Károly

    2015-04-01

    There is a huge unmet need to understand and treat pathological cognitive impairment. The development of disease modifying cognitive enhancers is hindered by the lack of correct pathomechanism and suitable animal models. Most animal models to study cognition and pathology do not fulfil either the predictive validity, face validity or construct validity criteria, and also outcome measures greatly differ from those of human trials. Fortunately, some pharmacological agents such as scopolamine evoke similar effects on cognition and cerebral circulation in rodents and humans and functional MRI enables us to compare cognitive agents directly in different species. In this paper we report the validation of a scopolamine based rodent pharmacological MRI provocation model. The effects of deemed procognitive agents (donepezil, vinpocetine, piracetam, alpha 7 selective cholinergic compounds EVP-6124, PNU-120596) were compared on the blood-oxygen-level dependent responses and also linked to rodent cognitive models. These drugs revealed significant effect on scopolamine induced blood-oxygen-level dependent change except for piracetam. In the water labyrinth test only PNU-120596 did not show a significant effect. This provocational model is suitable for testing procognitive compounds. These functional MR imaging experiments can be paralleled with human studies, which may help reduce the number of false cognitive clinical trials. PMID:25586394

  6. Carbon emissions trading scheme exploration in China: A multi-agent-based model

    International Nuclear Information System (INIS)

    To develop a low-carbon economy, China launched seven pilot programs for carbon emissions trading (CET) in 2011 and plans to establish a nationwide CET mechanism in 2015. This paper formulated a multi-agent-based model to investigate the impacts of different CET designs in order to find the most appropriate one for China. The proposed bottom-up model includes all main economic agents in a general equilibrium framework. The simulation results indicate that (1) CET would effectively reduce carbon emissions, with a certain negative impact on the economy, (2) as for allowance allocation, the grandfathering rule is relatively moderate, while the benchmarking rule is more aggressive, (3) as for the carbon price, when the price level in the secondary CET market is regulated to be around RMB 40 per metric ton, a satisfactory emission mitigation effect can be obtained, (4) the penalty rate is suggested to be carefully designed to balance the economy development and mitigation effect, and (5) subsidy policy for energy technology improvement can effectively reduce carbon emissions without an additional negative impact on the economy. The results also indicate that the proposed novel model is a promising tool for CET policy making and analyses. -- Highlights: •A multi-agent-based model is proposed for carbon emissions trading (CET) in China. •Three agents are included: government, firms in different sectors and households. •The impacts of CET on the economy and environment in China are analyzed. •Different CET designs are simulated to find an appropriate policy for China. •Results confirm the effectiveness of the model and give helpful insights into CET design

  7. Combining agent-based modeling and life cycle assessment for the evaluation of mobility policies.

    Science.gov (United States)

    Florent, Querini; Enrico, Benetto

    2015-02-01

    This article presents agent-based modeling (ABM) as a novel approach for consequential life cycle assessment (C-LCA) of large scale policies, more specifically mobility-related policies. The approach is validated at the Luxembourgish level (as a first case study). The agent-based model simulates the car market (sales, use, and dismantling) of the population of users in the period 2013-2020, following the implementation of different mobility policies and available electric vehicles. The resulting changes in the car fleet composition as well as the hourly uses of the vehicles are then used to derive consistent LCA results, representing the consequences of the policies. Policies will have significant environmental consequences: when using ReCiPe2008, we observe a decrease of global warming, fossil depletion, acidification, ozone depletion, and photochemical ozone formation and an increase of metal depletion, ionizing radiations, marine eutrophication, and particulate matter formation. The study clearly shows that the extrapolation of LCA results for the circulating fleet at national scale following the introduction of the policies from the LCAs of single vehicles by simple up-scaling (using hypothetical deployment scenarios) would be flawed. The inventory has to be directly conducted at full scale and to this aim, ABM is indeed a promising approach, as it allows identifying and quantifying emerging effects while modeling the Life Cycle Inventory of vehicles at microscale through the concept of agents. PMID:25587896

  8. The Evolution of Cooperation in Managed Groundwater Systems: An Agent-Based Modelling Approach

    Science.gov (United States)

    Castilla Rho, J. C.; Mariethoz, G.; Rojas, R. F.; Andersen, M. S.; Kelly, B. F.; Holley, C.

    2014-12-01

    Human interactions with groundwater systems often exhibit complex features that hinder the sustainable management of the resource. This leads to costly and persistent conflicts over groundwater at the catchment scale. One possible way to address these conflicts is by gaining a better understanding of how social and groundwater dynamics coevolve using agent-based models (ABM). Such models allow exploring 'bottom-up' solutions (i.e., self-organised governance systems), where the behaviour of individual agents (e.g., farmers) results in the emergence of mutual cooperation among groundwater users. There is significant empirical evidence indicating that this kind of 'bottom-up' approach may lead to more enduring and sustainable outcomes, compared to conventional 'top-down' strategies such as centralized control and water right schemes (Ostrom 1990). New modelling tools are needed to study these concepts systematically and efficiently. Our model uses a conceptual framework to study cooperation and the emergence of social norms as initially proposed by Axelrod (1986), which we adapted to groundwater management. We developed an ABM that integrates social mechanisms and the physics of subsurface flow. The model explicitly represents feedback between groundwater conditions and social dynamics, capturing the spatial structure of these interactions and the potential effects on cooperation levels in an agricultural setting. Using this model, we investigate a series of mechanisms that may trigger norms supporting cooperative strategies, which can be sustained and become stable over time. For example, farmers in a self-monitoring community can be more efficient at achieving the objective of sustainable groundwater use than government-imposed regulation. Our coupled model thus offers a platform for testing new schemes promoting cooperation and improved resource use, which can be used as a basis for policy design. Importantly, we hope to raise awareness of agent-based modelling as

  9. Integrated Agent-Based and Production Cost Modeling Framework for Renewable Energy Studies: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, Giulia

    2015-10-07

    The agent-based framework for renewable energy studies (ARES) is an integrated approach that adds an agent-based model of industry actors to PLEXOS and combines the strengths of the two to overcome their individual shortcomings. It can examine existing and novel wholesale electricity markets under high penetrations of renewables. ARES is demonstrated by studying how increasing levels of wind will impact the operations and the exercise of market power of generation companies that exploit an economic withholding strategy. The analysis is carried out on a test system that represents the Electric Reliability Council of Texas energy-only market in the year 2020. The results more realistically reproduce the operations of an energy market under different and increasing penetrations of wind, and ARES can be extended to address pressing issues in current and future wholesale electricity markets.

  10. Integrated Agent-Based and Production Cost Modeling Framework for Renewable Energy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, Giulia

    2016-01-08

    The agent-based framework for renewable energy studies (ARES) is an integrated approach that adds an agent-based model of industry actors to PLEXOS and combines the strengths of the two to overcome their individual shortcomings. It can examine existing and novel wholesale electricity markets under high penetrations of renewables. ARES is demonstrated by studying how increasing levels of wind will impact the operations and the exercise of market power of generation companies that exploit an economic withholding strategy. The analysis is carried out on a test system that represents the Electric Reliability Council of Texas energy-only market in the year 2020. The results more realistically reproduce the operations of an energy market under different and increasing penetrations of wind, and ARES can be extended to address pressing issues in current and future wholesale electricity markets.

  11. Agent-Based and Macroscopic Modeling of the Complex Socio-Economic Systems

    Directory of Open Access Journals (Sweden)

    Aleksejus Kononovičius

    2013-08-01

    Full Text Available Purpose – The focus of this contribution is the correspondence between collective behavior and inter-individual interactions in the complex socio-economic systems. Currently there is a wide selection of papers proposing various models for the both collective behavior and inter-individual interactions in the complex socio-economic systems. Yet the papers directly relating these two concepts are still quite rare. By studying this correspondence we discuss a cutting edge approach to the modeling of complex socio-economic systems. Design/methodology/approach – The collective behavior is often modeled using stochastic and ordinary calculus, while the inter-individual interactions are modeled using agent-based models. In order to obtain the ideal model, one should start from these frameworks and build a bridge to reach another. This is a formidable task, if we consider the top-down approach, namely starting from the collective behavior and moving towards inter-individual interactions. The bottom-up approach also fails, if complex inter-individual interaction models are considered, yet in this case we can start with simple models and increase the complexity as needed. Findings – The bottom-up approach, considering simple agent-based herding model as a model for the inter-individual interactions, allows us to derive certain macroscopic models of the complex socio-economic systems from the agent-based perspective. This provides interesting insights into the collective behavior patterns observed in the complex socio-economic systems. Research limitations/implications –The simplicity of the agent-based herding model might be considered to be somewhat limiting. Yet this simplicity implies that the model is highly universal. It reproduces universal features of social behavior and also can be further extended to fit different socio-economic scenarios. Practical implications – Insights provided in this contribution might be used to modify existing

  12. 基于规范的 Agent 混合结构模型研究%ON AGENT HYBRID ARCHITECTURE MODEL BASED ON NORM

    Institute of Scientific and Technical Information of China (English)

    杨海泷; 赵军

    2016-01-01

    Along with the continuous increase of the complexity of problems in management practices,computational experiments emerges as the times requiring.The rationality of Agent model construction,which is the subject in computational experiment method,has direct influence on the implementation and operation of the simulation system.Based on analysing the Agent concept,characteristics and existing Agent models,and combining with the theories related to management science,norm and computational experiments,this paper puts forward a norm-based Agent hybrid architecture model,and presents a base class design of Agent.At last the simulation is made on a practical example based on Swarm platform.Simulation results show that the Agent model has the feasibility,and is suitable for multi-Agent modelling in computational experiment method of management science field.%随着管理问题复杂性不断提高,计算实验方法应运而生。Agent 作为计算实验方法中的主体,其模型构建的合理与否直接影响到仿真系统的实现与运行。通过研究 Agent 概念、特点以及已有 Agent 模型,结合管理科学、规范和计算实验相关理论,提出一种基于规范的 Agent 混合结构模型,并给出 Agent 的基类设计。最后,运用 Swarm 平台对一个实际案例进行仿真。仿真结果证明,该 Agent 模型具有可行性,适合于管理科学领域计算实验方法中的多 Agent 建模。

  13. Turning green: Agent-based modeling of the adoption of dynamic electricity tariffs

    International Nuclear Information System (INIS)

    Using an agent-based modeling approach we study the temporal dynamics of consumer opinions regarding switching to dynamic electricity tariffs and the actual decisions to switch. We assume that the decision to switch is based on the unanimity of τ past opinions. The resulting model offers a hypothetical, yet plausible explanation of why there is such a big discrepancy between consumer opinions, as measured by market surveys, and the actual participation in pilot programs and the adoption of dynamic tariffs. We argue that due to the high indifference level in today's retail electricity markets, customer opinions are very unstable and change frequently. The conducted simulation study shows that reducing the indifference level can result in narrowing the intention–behavior gap. A similar effect can be achieved by decreasing the decision time that a consumer takes to make a decision. - Highlights: • We propose an agent-based model to study the adoption of dynamic electricity tariffs. • The decision to change the tariff is based on the unanimity of τ past opinions. • The model explains why the empirically observed intention–behavior gap exists. • The adoption of dynamic tariffs is impossible due to the high level of indifference in today's societies. • Reducing the indifference level or decreasing the decision time can result in narrowing the gap

  14. Agent-based modeling of endotoxin-induced acute inflammatory response in human blood leukocytes.

    Directory of Open Access Journals (Sweden)

    Xu Dong

    Full Text Available BACKGROUND: Inflammation is a highly complex biological response evoked by many stimuli. A persistent challenge in modeling this dynamic process has been the (nonlinear nature of the response that precludes the single-variable assumption. Systems-based approaches offer a promising possibility for understanding inflammation in its homeostatic context. In order to study the underlying complexity of the acute inflammatory response, an agent-based framework is developed that models the emerging host response as the outcome of orchestrated interactions associated with intricate signaling cascades and intercellular immune system interactions. METHODOLOGY/PRINCIPAL FINDINGS: An agent-based modeling (ABM framework is proposed to study the nonlinear dynamics of acute human inflammation. The model is implemented using NetLogo software. Interacting agents involve either inflammation-specific molecules or cells essential for the propagation of the inflammatory reaction across the system. Spatial orientation of molecule interactions involved in signaling cascades coupled with the cellular heterogeneity are further taken into account. The proposed in silico model is evaluated through its ability to successfully reproduce a self-limited inflammatory response as well as a series of scenarios indicative of the nonlinear dynamics of the response. Such scenarios involve either a persistent (noninfectious response or innate immune tolerance and potentiation effects followed by perturbations in intracellular signaling molecules and cascades. CONCLUSIONS/SIGNIFICANCE: The ABM framework developed in this study provides insight on the stochastic interactions of the mediators involved in the propagation of endotoxin signaling at the cellular response level. The simulation results are in accordance with our prior research effort associated with the development of deterministic human inflammation models that include transcriptional dynamics, signaling, and physiological

  15. Applying System Dynamics and Agent-based Modelling in Archaeological Simulation

    Czech Academy of Sciences Publication Activity Database

    Olševičová, K.; Danielisová, Alžběta

    Olomouc : Palacký University, 2014 - (Talašová, J.; Stoklasa, J.; Talášek, T.), s. 721-726 ISBN 978-80-244-4209-9. [MME 2014. International Conference Mathematical Methods in Economics /32./. Olomouc (CZ), 10.09.2014-12.09.2014] R&D Projects: GA ČR GAP405/12/0926 Institutional support: RVO:67985912 Keywords : agent-based model * cellular automata * land use model * NetLogo * sustainability * system dynamics Subject RIV: AC - Archeology, Anthropology, Ethnology

  16. Agent-based model with asymmetric trading and herding for complex financial systems.

    Directory of Open Access Journals (Sweden)

    Jun-Jie Chen

    Full Text Available BACKGROUND: For complex financial systems, the negative and positive return-volatility correlations, i.e., the so-called leverage and anti-leverage effects, are particularly important for the understanding of the price dynamics. However, the microscopic origination of the leverage and anti-leverage effects is still not understood, and how to produce these effects in agent-based modeling remains open. On the other hand, in constructing microscopic models, it is a promising conception to determine model parameters from empirical data rather than from statistical fitting of the results. METHODS: To study the microscopic origination of the return-volatility correlation in financial systems, we take into account the individual and collective behaviors of investors in real markets, and construct an agent-based model. The agents are linked with each other and trade in groups, and particularly, two novel microscopic mechanisms, i.e., investors' asymmetric trading and herding in bull and bear markets, are introduced. Further, we propose effective methods to determine the key parameters in our model from historical market data. RESULTS: With the model parameters determined for six representative stock-market indices in the world, respectively, we obtain the corresponding leverage or anti-leverage effect from the simulation, and the effect is in agreement with the empirical one on amplitude and duration. At the same time, our model produces other features of the real markets, such as the fat-tail distribution of returns and the long-term correlation of volatilities. CONCLUSIONS: We reveal that for the leverage and anti-leverage effects, both the investors' asymmetric trading and herding are essential generation mechanisms. Among the six markets, however, the investors' trading is approximately symmetric for the five markets which exhibit the leverage effect, thus contributing very little. These two microscopic mechanisms and the methods for the

  17. cystiSim - an agent-based model for Taenia solium transmission and control

    DEFF Research Database (Denmark)

    Braae, Uffe Christian; Devleesschauwer, Brecht; Gabriël, Sarah;

    Sim, an agent-based model for T. solium transmission and control. The model was developed in R and is publicly available as an R package (https://github.com/brechtdv/cystiSim/). The model description adheres to the Overview, Design concepts, and Details (ODD) protocol. The model consists of two entities: pigs...... interventions measures or combinations hereof: human mass drug administration (MDA), pig MDA, and pig vaccination. From the modelled simulations, cystiSim suggests that the combination of pig MDA and vaccination may have promising results. However, pig MDA as a standalone tool also provides a significant effect...... and humans. Pigs acquire cysticercosis through the environment or by direct contact with a tapeworm carrier's faeces, leading to light or high infection intensities, respectively. Humans acquire taeniosis from slaughtered pigs proportional to their infection intensity. The model allows evaluation of three...

  18. Agent-based model for the h-index - exact solution

    Science.gov (United States)

    Żogała-Siudem, Barbara; Siudem, Grzegorz; Cena, Anna; Gagolewski, Marek

    2016-01-01

    Hirsch's h-index is perhaps the most popular citation-based measure of scientific excellence. In 2013, Ionescu and Chopard proposed an agent-based model describing a process for generating publications and citations in an abstract scientific community [G. Ionescu, B. Chopard, Eur. Phys. J. B 86, 426 (2013)]. Within such a framework, one may simulate a scientist's activity, and - by extension - investigate the whole community of researchers. Even though the Ionescu and Chopard model predicts the h-index quite well, the authors provided a solution based solely on simulations. In this paper, we complete their results with exact, analytic formulas. What is more, by considering a simplified version of the Ionescu-Chopard model, we obtained a compact, easy to compute formula for the h-index. The derived approximate and exact solutions are investigated on a simulated and real-world data sets.

  19. Agent Based Modeling of Air Carrier Behavior for Evaluation of Technology Equipage and Adoption

    Science.gov (United States)

    Horio, Brant M.; DeCicco, Anthony H.; Stouffer, Virginia L.; Hasan, Shahab; Rosenbaum, Rebecca L.; Smith, Jeremy C.

    2014-01-01

    As part of ongoing research, the National Aeronautics and Space Administration (NASA) and LMI developed a research framework to assist policymakers in identifying impacts on the U.S. air transportation system (ATS) of potential policies and technology related to the implementation of the Next Generation Air Transportation System (NextGen). This framework, called the Air Transportation System Evolutionary Simulation (ATS-EVOS), integrates multiple models into a single process flow to best simulate responses by U.S. commercial airlines and other ATS stakeholders to NextGen-related policies, and in turn, how those responses impact the ATS. Development of this framework required NASA and LMI to create an agent-based model of airline and passenger behavior. This Airline Evolutionary Simulation (AIRLINE-EVOS) models airline decisions about tactical airfare and schedule adjustments, and strategic decisions related to fleet assignments, market prices, and equipage. AIRLINE-EVOS models its own heterogeneous population of passenger agents that interact with airlines; this interaction allows the model to simulate the cycle of action-reaction as airlines compete with each other and engage passengers. We validated a baseline configuration of AIRLINE-EVOS against Airline Origin and Destination Survey (DB1B) data and subject matter expert opinion, and we verified the ATS-EVOS framework and agent behavior logic through scenario-based experiments. These experiments demonstrated AIRLINE-EVOS's capabilities in responding to an input price shock in fuel prices, and to equipage challenges in a series of analyses based on potential incentive policies for best equipped best served, optimal-wind routing, and traffic management initiative exemption concepts..

  20. Modeling and simulation of virtual human's coordination based on multi-agent systems

    Science.gov (United States)

    Zhang, Mei; Wen, Jing-Hua; Zhang, Zu-Xuan; Zhang, Jian-Qing

    2006-10-01

    The difficulties and hotspots researched in current virtual geographic environment (VGE) are sharing space and multiusers operation, distributed coordination and group decision-making. The theories and technologies of MAS provide a brand-new environment for analysis, design and realization of distributed opening system. This paper takes cooperation among virtual human in VGE which multi-user participate in as main researched object. First we describe theory foundation truss of VGE, and present the formalization description of Multi-Agent System (MAS). Then we detailed analyze and research arithmetic of collectivity operating behavior learning of virtual human based on best held Genetic Algorithm(GA), and establish dynamics action model which Multi-Agents and object interact dynamically and colony movement strategy. Finally we design a example which shows how 3 evolutional Agents cooperate to complete the task of colony pushing column box, and design a virtual world prototype of virtual human pushing box collectively based on V-Realm Builder 2.0, moreover we make modeling and dynamic simulation with Simulink 6.

  1. A MARKET-ORIENTED AGENTS-BASED MODEL FOR INFORMATION RETRIEVAL

    Directory of Open Access Journals (Sweden)

    Djamel Eddine Menacer

    2014-03-01

    Full Text Available Information Retrieval in the World Wide Web (Web IR is essential for a number of activities and it is an active domain of research and devel-opment. The main challenges concern the rele-vance of the results provided to users' queries and the performance regarding respond-time. On the other hand, agent-based market systems prove to be efficient for implementing e-commerce or B2B applications on the internet, thanks to inherent properties such as prominency of interactions, scalability, flexibility, interoper-ability, etc. Although the use of agents in other application domains is not yet widespread, the integration of mobile agents into market mecha-nisms bring clear and efficient solutions to Qual-ity of Service issues encountered in most distrib-uted applications and notably in Web IR systems. Mobility allows defining the seller – buyer model of interaction, where agents act on behalf of final users or devices providing re-sources, while the generic Market Place archi-tecture provides an organizational setting for the matching of demands and offers. The paper shows how this framework applies to Web IR and provides experimental validation results from a Jade implementation.

  2. Introducing spatial information into predictive NF-kappaB modelling--an agent-based approach.

    Directory of Open Access Journals (Sweden)

    Mark Pogson

    Full Text Available Nature is governed by local interactions among lower-level sub-units, whether at the cell, organ, organism, or colony level. Adaptive system behaviour emerges via these interactions, which integrate the activity of the sub-units. To understand the system level it is necessary to understand the underlying local interactions. Successful models of local interactions at different levels of biological organisation, including epithelial tissue and ant colonies, have demonstrated the benefits of such 'agent-based' modelling. Here we present an agent-based approach to modelling a crucial biological system--the intracellular NF-kappaB signalling pathway. The pathway is vital to immune response regulation, and is fundamental to basic survival in a range of species. Alterations in pathway regulation underlie a variety of diseases, including atherosclerosis and arthritis. Our modelling of individual molecules, receptors and genes provides a more comprehensive outline of regulatory network mechanisms than previously possible with equation-based approaches. The method also permits consideration of structural parameters in pathway regulation; here we predict that inhibition of NF-kappaB is directly affected by actin filaments of the cytoskeleton sequestering excess inhibitors, therefore regulating steady-state and feedback behaviour.

  3. Agent-based organizational modelling for analysis of safety culture at an air navigation service provider

    International Nuclear Information System (INIS)

    Assessment of safety culture is done predominantly by questionnaire-based studies, which tend to reveal attitudes on immaterial characteristics (values, beliefs, norms). There is a need for a better understanding of the implications of the material aspects of an organization (structures, processes, etc.) for safety culture and their interactions with the immaterial characteristics. This paper presents a new agent-based organizational modelling approach for integrated and systematic evaluation of material and immaterial characteristics of socio-technical organizations in safety culture analysis. It uniquely considers both the formal organization and the value- and belief-driven behaviour of individuals in the organization. Results are presented of a model for safety occurrence reporting at an air navigation service provider. Model predictions consistent with questionnaire-based results are achieved. A sensitivity analysis provides insight in organizational factors that strongly influence safety culture indicators. The modelling approach can be used in combination with attitude-focused safety culture research, towards an integrated evaluation of material and immaterial characteristics of socio-technical organizations. By using this approach an organization is able to gain a deeper understanding of causes of diverse problems and inefficiencies both in the formal organization and in the behaviour of organizational agents, and to systematically identify and evaluate improvement options.

  4. Buying on margin, selling short in an agent-based market model

    Science.gov (United States)

    Zhang, Ting; Li, Honggang

    2013-09-01

    Credit trading, or leverage trading, which includes buying on margin and selling short, plays an important role in financial markets, where agents tend to increase their leverages for increased profits. This paper presents an agent-based asset market model to study the effect of the permissive leverage level on traders’ wealth and overall market indicators. In this model, heterogeneous agents can assume fundamental value-converging expectations or trend-persistence expectations, and their effective demands of assets depend both on demand willingness and wealth constraints, where leverage can relieve the wealth constraints to some extent. The asset market price is determined by a market maker, who watches the market excess demand, and is influenced by noise factors. By simulations, we examine market results for different leverage ratios. At the individual level, we focus on how the leverage ratio influences agents’ wealth accumulation. At the market level, we focus on how the leverage ratio influences changes in the asset price, volatility, and trading volume. Qualitatively, our model provides some meaningful results supported by empirical facts. More importantly, we find a continuous phase transition as we increase the leverage threshold, which may provide a further prospective of credit trading.

  5. An agent-based approach for modeling dynamics of contagious disease spread

    Directory of Open Access Journals (Sweden)

    Dragicevic Suzana

    2009-08-01

    Full Text Available Abstract Background The propagation of communicable diseases through a population is an inherent spatial and temporal process of great importance for modern society. For this reason a spatially explicit epidemiologic model of infectious disease is proposed for a greater understanding of the disease's spatial diffusion through a network of human contacts. Objective The objective of this study is to develop an agent-based modelling approach the integrates geographic information systems (GIS to simulate the spread of a communicable disease in an urban environment, as a result of individuals' interactions in a geospatial context. Methods The methodology for simulating spatiotemporal dynamics of communicable disease propagation is presented and the model is implemented using measles outbreak in an urban environment as a case study. Individuals in a closed population are explicitly represented by agents associated to places where they interact with other agents. They are endowed with mobility, through a transportation network allowing them to move between places within the urban environment, in order to represent the spatial heterogeneity and the complexity involved in infectious diseases diffusion. The model is implemented on georeferenced land use dataset from Metro Vancouver and makes use of census data sets from Statistics Canada for the municipality of Burnaby, BC, Canada study site. Results The results provide insights into the application of the model to calculate ratios of susceptible/infected in specific time frames and urban environments, due to its ability to depict the disease progression based on individuals' interactions. It is demonstrated that the dynamic spatial interactions within the population lead to high numbers of exposed individuals who perform stationary activities in areas after they have finished commuting. As a result, the sick individuals are concentrated in geographical locations like schools and universities. Conclusion

  6. Evolutionary Agent-based Models to design distributed water management strategies

    Science.gov (United States)

    Giuliani, M.; Castelletti, A.; Reed, P. M.

    2012-12-01

    There is growing awareness in the scientific community that the traditional centralized approach to water resources management, as described in much of the water resources literature, provides an ideal optimal solution, which is certainly useful to quantify the best physically achievable performance, but is generally inapplicable. Most real world water resources management problems are indeed characterized by the presence of multiple, distributed and institutionally-independent decision-makers. Multi-Agent Systems provide a potentially more realistic alternative framework to model multiple and self-interested decision-makers in a credible context. Each decision-maker can be represented by an agent who, being self-interested, acts according to local objective functions and produces negative externalities on system level objectives. Different levels of coordination can potentially be included in the framework by designing coordination mechanisms to drive the current decision-making structure toward the global system efficiency. Yet, the identification of effective coordination strategies can be particularly complex in modern institutional contexts and current practice is dependent on largely ad-hoc coordination strategies. In this work we propose a novel Evolutionary Agent-based Modeling (EAM) framework that enables a mapping of fully uncoordinated and centrally coordinated solutions into their relative "many-objective" tradeoffs using multiobjective evolutionary algorithms. Then, by analysing the conflicts between local individual agent and global system level objectives it is possible to more fully understand the causes, consequences, and potential solution strategies for coordination failures. Game-theoretic criteria have value for identifying the most interesting alternatives from a policy making point of view as well as the coordination mechanisms that can be applied to obtain these interesting solutions. The proposed approach is numerically tested on a

  7. Information, Meaning and Eigenforms: In the Light of Sociology, Agent-Based Modeling and AI

    Directory of Open Access Journals (Sweden)

    Manfred Füllsack

    2012-08-01

    Full Text Available The paper considers the relation of Shannon-type information to those semantic and hermeneutic aspects of communication, which are often referred to as meaning. It builds on considerations of Talcott Parsons, Niklas Luhmann and Robert K. Logan and relates them to an agent-based model that reproduces key aspects of the Talking Head experiment by Luc Steels. The resulting insights seem to give reason to regard information and meaning not as qualitatively different entities, but as interrelated forms of order that emerge in the interaction of autonomous (self-referentially closed agents. Although on first sight, this way of putting information and meaning into a constructivist framework seems to open possibilities to conceive meaning in terms of Shannon-information, it also suggests a re-conceptualization of information in terms of what cybernetics calls Eigenform in order to do justice to its dynamic interrelation with meaning.

  8. Agent-based modeling of a multi-room multi-floor building emergency evacuation

    Science.gov (United States)

    Ha, Vi; Lykotrafitis, George

    2012-04-01

    Panic during emergency building evacuation can cause crowd stampede, resulting in serious injuries and casualties. Agent-based methods have been successfully employed to investigate the collective human behavior during emergency evacuation in cases where the configurational space is extremely simple-usually one rectangular room-but not in evacuations of multi-room or multi-floor buildings. This implies that the effect of the complexity of building architecture on the collective behavior of the agents during evacuation has not been fully investigated. Here, we employ a system of self-moving particles whose motion is governed by the social-force model to investigate the effect of complex building architecture on the uncoordinated crowd motion during urgent evacuation. In particular, we study how the room door size, the size of the main exit, the desired speed and the friction coefficient affect the evacuation time and under what circumstances the evacuation efficiency improves.

  9. An agent-based model to study market penetration of plug-in hybrid electric vehicles

    International Nuclear Information System (INIS)

    A spatially explicit agent-based vehicle consumer choice model is developed to explore sensitivities and nonlinear interactions between various potential influences on plug-in hybrid vehicle (PHEV) market penetration. The model accounts for spatial and social effects (including threshold effects, homophily, and conformity) and media influences. Preliminary simulations demonstrate how such a model could be used to identify nonlinear interactions among potential leverage points, inform policies affecting PHEV market penetration, and help identify future data collection necessary to more accurately model the system. We examine sensitivity of the model to gasoline prices, to accuracy in estimation of fuel costs, to agent willingness to adopt the PHEV technology, to PHEV purchase price and rebates, to PHEV battery range, and to heuristic values related to gasoline usage. Our simulations indicate that PHEV market penetration could be enhanced significantly by providing consumers with ready estimates of expected lifetime fuel costs associated with different vehicles (e.g., on vehicle stickers), and that increases in gasoline prices could nonlinearly magnify the impact on fleet efficiency. We also infer that a potential synergy from a gasoline tax with proceeds is used to fund research into longer-range lower-cost PHEV batteries. - Highlights: → We model consumer agents to study potential market penetration of PHEVs. → The model accounts for spatial, social, and media effects. → We identify interactions among potential leverage points that could inform policy. → Consumer access to expected lifetime fuel costs may enhance PHEV market penetration. → Increasing PHEV battery range has synergistic effects on fleet efficiency.

  10. Analysis of phase transition points for a two-color agent-based model

    Science.gov (United States)

    Shin, J. K.; Jung, P. S.

    2013-04-01

    The agent-based model treated in the present study describes dynamics of two types of population in a gravity-like potential field. In previous studies, the model was known to exhibit various spatiotemporal patterns on two-dimensioanl lattice systems. However, the patterns were classified depending purely on eye observations, and the underlying dynamics of these patterns were not fully explored. It remained a question to be answered if these eye observation-based classifications could be confirmed by any analytical means. To pursue the question, we first suggest several analytic quantities, such as convergence time steps and reaction speed, to replace the eye observations. As a result, we show that a phase diagram can be reasonably drawn on the contour diagram of the time steps. In addition, we find a power-law scaling in the reaction speed, confirming that a phase transition really is involved there. Next, as a main part of the present study, we apply analytical methods to calculate two important phase transition points from the system. The results from the analytical approach agreed well with the numerically obtained phase transition points from the agent-based model. In general, the paper serves as an example study of estimating global phenomena of complex systems in terms of local parameters of the system.

  11. The role of taste affinity in agent-based models for social recommendation

    CERN Document Server

    Cimini, Giulio; Medo, Matus; Chen, Duanbing

    2013-01-01

    In the Internet era, online social media emerged as the main tool for sharing opinions and information among individuals. In this work we study an adaptive model of a social network where directed links connect users with similar tastes, and over which information propagates through social recommendation. Agent-based simulations of two different artificial settings for modeling user tastes are compared with patterns seen in real data, suggesting that users differing in their scope of interests is a more realistic assumption than users differing only in their particular interests. We further introduce an extensive set of similarity metrics based on users' past assessments, and evaluate their use in the given social recommendation model with both artificial simulations and real data. Superior recommendation performance is observed for similarity metrics that give preference to users with small scope---who thus act as selective filters in social recommendation.

  12. Ising-like agent-based technology diffusion model: adoption patterns vs. seeding strategies

    CERN Document Server

    Laciana, Carlos E

    2010-01-01

    The well-known Ising model used in statistical physics was adapted to a social dynamics context to simulate the adoption of a technological innovation. The model explicitly combines (a) an individual's perception of the advantages of an innovation and (b) social influence from members of the decision-maker's social network. The micro-level adoption dynamics are embedded into an agent-based model that allows exploration of macro-level patterns of technology diffusion throughout systems with different configurations (number and distributions of early adopters, social network topologies). In the present work we carry out many numerical simulations. We find that when the gap between the individual's perception of the options is high, the adoption speed increases if the dispersion of early adopters grows. Another test was based on changing the network topology by means of stochastic connections to a common opinion reference (hub), which resulted in an increment in the adoption speed. Finally, we performed a simula...

  13. An agent based multi-optional model for the diffusion of innovations

    Science.gov (United States)

    Laciana, Carlos E.; Oteiza-Aguirre, Nicolás

    2014-01-01

    We propose a model for the diffusion of several products competing in a common market based on the generalization of the Ising model of statistical mechanics (Potts model). Using an agent based implementation we analyze two problems: (i) a three options case, i.e. to adopt a product A, a product B, or non-adoption and (ii) a four option case, i.e. the adoption of product A, product B, both, or none. In the first case we analyze a launching strategy for one of the two products, which delays its launching with the objective of competing with improvements. Market shares reached by each product are then estimated at market saturation. Finally, simulations are carried out with varying degrees of social network topology, uncertainty, and population homogeneity.

  14. An Agent-Based Dynamic Model for Analysis of Distributed Space Exploration Architectures

    Science.gov (United States)

    Sindiy, Oleg V.; DeLaurentis, Daniel A.; Stein, William B.

    2009-07-01

    A range of complex challenges, but also potentially unique rewards, underlie the development of exploration architectures that use a distributed, dynamic network of resources across the solar system. From a methodological perspective, the prime challenge is to systematically model the evolution (and quantify comparative performance) of such architectures, under uncertainty, to effectively direct further study of specialized trajectories, spacecraft technologies, concept of operations, and resource allocation. A process model for System-of-Systems Engineering is used to define time-varying performance measures for comparative architecture analysis and identification of distinguishing patterns among interoperating systems. Agent-based modeling serves as the means to create a discrete-time simulation that generates dynamics for the study of architecture evolution. A Solar System Mobility Network proof-of-concept problem is introduced representing a set of longer-term, distributed exploration architectures. Options within this set revolve around deployment of human and robotic exploration and infrastructure assets, their organization, interoperability, and evolution, i.e., a system-of-systems. Agent-based simulations quantify relative payoffs for a fully distributed architecture (which can be significant over the long term), the latency period before they are manifest, and the up-front investment (which can be substantial compared to alternatives). Verification and sensitivity results provide further insight on development paths and indicate that the framework and simulation modeling approach may be useful in architectural design of other space exploration mass, energy, and information exchange settings.

  15. Agent-based model for the h-index - Exact solution

    CERN Document Server

    Żogała-Siudem, Barbara; Cena, Anna; Gagolewski, Marek

    2015-01-01

    The Hirsch's $h$-index is perhaps the most popular citation-based measure of the scientific excellence. In 2013 G. Ionescu and B. Chopard proposed an agent-based model for this index to describe a publications and citations generation process in an abstract scientific community. With such an approach one can simulate a single scientist's activity, and by extension investigate the whole community of researchers. Even though this approach predicts quite well the $h$-index from bibliometric data, only a solution based on simulations was given. In this paper, we complete their results with exact, analytic formulas. What is more, due to our exact solution we are able to simplify the Ionescu-Chopard model which allows us to obtain a compact formula for $h$-index. Moreover, a simulation study designed to compare both, approximated and exact, solutions is included. The last part of this paper presents evaluation of the obtained results on a real-word data set.

  16. Bayesian networks and agent-based modeling approach for urban land-use and population density change: a BNAS model

    Science.gov (United States)

    Kocabas, Verda; Dragicevic, Suzana

    2013-10-01

    Land-use change models grounded in complexity theory such as agent-based models (ABMs) are increasingly being used to examine evolving urban systems. The objective of this study is to develop a spatial model that simulates land-use change under the influence of human land-use choice behavior. This is achieved by integrating the key physical and social drivers of land-use change using Bayesian networks (BNs) coupled with agent-based modeling. The BNAS model, integrated Bayesian network-based agent system, presented in this study uses geographic information systems, ABMs, BNs, and influence diagram principles to model population change on an irregular spatial structure. The model is parameterized with historical data and then used to simulate 20 years of future population and land-use change for the City of Surrey, British Columbia, Canada. The simulation results identify feasible new urban areas for development around the main transportation corridors. The obtained new development areas and the projected population trajectories with the“what-if” scenario capabilities can provide insights into urban planners for better and more informed land-use policy or decision-making processes.

  17. Learning Natural Selection in 4th Grade with Multi-Agent-Based Computational Models

    Science.gov (United States)

    Dickes, Amanda Catherine; Sengupta, Pratim

    2013-06-01

    In this paper, we investigate how elementary school students develop multi-level explanations of population dynamics in a simple predator-prey ecosystem, through scaffolded interactions with a multi-agent-based computational model (MABM). The term "agent" in an MABM indicates individual computational objects or actors (e.g., cars), and these agents obey simple rules assigned or manipulated by the user (e.g., speeding up, slowing down, etc.). It is the interactions between these agents, based on the rules assigned by the user, that give rise to emergent, aggregate-level behavior (e.g., formation and movement of the traffic jam). Natural selection is such an emergent phenomenon, which has been shown to be challenging for novices (K16 students) to understand. Whereas prior research on learning evolutionary phenomena with MABMs has typically focused on high school students and beyond, we investigate how elementary students (4th graders) develop multi-level explanations of some introductory aspects of natural selection—species differentiation and population change—through scaffolded interactions with an MABM that simulates predator-prey dynamics in a simple birds-butterflies ecosystem. We conducted a semi-clinical interview based study with ten participants, in which we focused on the following: a) identifying the nature of learners' initial interpretations of salient events or elements of the represented phenomena, b) identifying the roles these interpretations play in the development of their multi-level explanations, and c) how attending to different levels of the relevant phenomena can make explicit different mechanisms to the learners. In addition, our analysis also shows that although there were differences between high- and low-performing students (in terms of being able to explain population-level behaviors) in the pre-test, these differences disappeared in the post-test.

  18. A Call to Arms: Standards for Agent-Based Modeling and Simulation

    OpenAIRE

    Andrew Collins; Mikel Petty; Daniele Vernon-Bido; Solomon Sherfey

    2015-01-01

    Standards are as old as civilization itself and they are vital to human development. Standards touch almost every part of our lives, from the water we drink to the language used to write this article. A sign of a good standard is one that we do not notice. Good standards exist and so do processes and organizations to create and maintain them. As agent-based modeling and simulation matures as a methodology, a discussion of standards applicable to it becomes increasingly important. Descriptive ...

  19. Using an Agent-Based Modeling Simulation and Game to Teach Socio-Scientific Topics

    Directory of Open Access Journals (Sweden)

    Lori L. Scarlatos

    2014-02-01

    Full Text Available In our modern world, where science, technology and society are tightly interwoven, it is essential that all students be able to evaluate scientific evidence and make informed decisions. Energy Choices, an agent-based simulation with a multiplayer game interface, was developed as a learning tool that models the interdependencies between the energy choices that are made, growth in local economies, and climate change on a global scale. This paper presents the results of pilot testing Energy Choices in two different settings, using two different modes of delivery.

  20. Simulation of the Role of Government in Spatial Agent-Based Model

    Directory of Open Access Journals (Sweden)

    Viktor Ivanovich Suslov

    2016-09-01

    Full Text Available The paper describes the further development of an agent-based multiregional input-output model of the Russian economy. We consider the idea of incorporating the government into the model and analyze the results of experimental calculations for the conditional example of spatial economy. New agents are included into the model such as the federal and regional governments, pension fund and also the state enterprises producing public goods at the federal and regional levels. The government sets four types of taxes (personal and business income taxes, VAT and payroll taxes, ensures the provision of public goods and provides social, investment and interbudgetary transfers to households, firms and budgets. Social transfers consist of social assistance and unemployment benefits. The utility functions of households are expanded by the terms associated with national and regional public goods. The budget policy is designed in accordance with the maximization of isoelastic function of social welfare that formalizes the choice between the different concepts of social justice. The Gini index is used for the monitoring the inequality of income distribution. The results of experimental calculations present the convergence of the new version of the model to the state of quasi-equilibrium. The special attention is paid an optimal level of the taxation maximizing the social welfare function. Four variants of the optimal tax rates are defined: for three major taxes at a fixed proportion of rates and for each of the tax separately at zero rates of two other taxes. The further directions of modelling are identified, they allow to investigate the spatial development of the Russian economy taking into account the decision-making by private agents in responding to government policies.

  1. Encouraging Sustainable Transport Choices in American Households: Results from an Empirically Grounded Agent-Based Model

    Directory of Open Access Journals (Sweden)

    Davide Natalini

    2013-12-01

    Full Text Available The transport sector needs to go through an extended process of decarbonisation to counter the threat of climate change. Unfortunately, the International Energy Agency forecasts an enormous growth in the number of cars and greenhouse gas emissions by 2050. Two issues can thus be identified: (1 the need for a new methodology that could evaluate the policy performances ex-ante and (2 the need for more effective policies. To help address these issues, we developed an Agent-Based Model called Mobility USA aimed at: (1 testing whether this could be an effective approach in analysing ex-ante policy implementation in the transport sector; and (2 evaluating the effects of alternative policy scenarios on commuting behaviours in the USA. Particularly, we tested the effects of two sets of policies, namely market-based and preference-change ones. The model results suggest that this type of agent-based approach will provide a useful tool for testing policy interventions and their effectiveness.

  2. Opening the black box—Development, testing and documentation of a mechanistically rich agent-based model

    DEFF Research Database (Denmark)

    Topping, Chris J.; Høye, Toke; Olesen, Carsten Riis

    2010-01-01

    Although increasingly widely used in biology, complex adaptive simulation models such as agent-based models have been criticised for being difficult to communicate and test. This study demonstrates the application of pattern-oriented model testing, and a novel documentation procedure to present...... a detailed agent-based model of the European brown hare, a species in widespread decline in Europe. The model was built based on available literature data, using multiple field data patterns from an island hare population study to guide model development. A general and widely applicable approach...... to the pattern-oriented protocol for testing and developing ecological models of this kind was defined together with the development of the ODdox documentation protocol, a combination of the current ODD protocol for describing agent-based models and source-code documentation. The result is a detailed and yet...

  3. A secure model for mobile agent based on encrypted circuit construction

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yan; WANG Ruchuan; MU Hong; WANG Haiyan

    2007-01-01

    As a new technology,mobile agent (MA) shows a wide application in the field of network technology.However,security has been one of the crucial problems in its application.A new protection model based on a trusted element is presented in this paper.The trusted element,which differs from the traditional trusted hardware such as a smart card or a co-processor,offers a third party service based on an encrypted circuit construction.The procedure of constructing an encrypted circuit is introduced and the method of using the trusted service to protect the MA is also described.An application example is given to show how to use the new model at the end of the paper.

  4. Agent-Based Modeling in Supply Chain Management:A Genetic Algorithm and Fuzzy Logic Approach

    Directory of Open Access Journals (Sweden)

    Meriem DJENNAS

    2012-09-01

    Full Text Available In today’s global market, reaching a competitive advantage by integrating firms in a supply chain management strategy becomes a key success for any firm seeking to survive in a complex environment. However, as interactions among agents in the supply chain management (SCM remain unpredictable, simulation appears as a powerful tool aiming to predict market behavior and agents’ performance levels. This paper discusses the issues of supply chain management and the requirements for supply chain simulation modeling. It reviews the relationships amongArtificial Intelligence (AI and SCM and concludes that under some conditions, SCM models exhibit some inadequacies that may be enriched by the use of AI tools. This approach aims to test the supply chain activities of nine companies in the crude oil market. The objective is to tackle the issues under which agents can coexist in a competitive environment. Furthermore, we will specify the supply chain management trading interaction amongagents by using an optimization approach based on a Genetic Algorithm (AG, Clustering and Fuzzy Logic (FL.Results support the view that the structured model provides a good tool for modeling the supply chain activities using AI methodology.

  5. Agent-Based Modeling in Supply Chain Management:A Genetic Algorithm and Fuzzy Logic Approach

    Directory of Open Access Journals (Sweden)

    Meriem Djennas

    2012-10-01

    Full Text Available In today’s global market, reaching a competitive advantage by integrating firms in a supply chainmanagement strategy becomes a key success for any firm seeking to survive in a complex environment.However, as interactions among agents in the supply chain management (SCM remain unpredictable,simulation appears as a powerful tool aiming to predict market behavior and agents’ performance levels.This paper discusses the issues of supply chain management and the requirements for supply chainsimulation modeling. It reviews the relationships amongArtificial Intelligence (AI and SCM and concludesthat under some conditions, SCM models exhibit some inadequacies that may be enriched by the use of AItools. This approach aims to test the supply chain activities of nine companies in the crude oil market. Theobjective is to tackle the issues under which agents can coexist in a competitive environment. Furthermore,we will specify the supply chain management trading interaction amongagents by using an optimizationapproach based on a Genetic Algorithm (AG, Clustering and Fuzzy Logic (FL.Results support the viewthat the structured model provides a good tool for modeling the supply chain activities using AImethodology.

  6. Physics and financial economics (1776–2014): puzzles, Ising and agent-based models

    International Nuclear Information System (INIS)

    This short review presents a selected history of the mutual fertilization between physics and economics—from Isaac Newton and Adam Smith to the present. The fundamentally different perspectives embraced in theories developed in financial economics compared with physics are dissected with the examples of the volatility smile and of the excess volatility puzzle. The role of the Ising model of phase transitions to model social and financial systems is reviewed, with the concepts of random utilities and the logit model as the analog of the Boltzmann factor in statistical physics. Recent extensions in terms of quantum decision theory are also covered. A wealth of models are discussed briefly that build on the Ising model and generalize it to account for the many stylized facts of financial markets. A summary of the relevance of the Ising model and its extensions is provided to account for financial bubbles and crashes. The review would be incomplete if it did not cover the dynamical field of agent-based models (ABMs), also known as computational economic models, of which the Ising-type models are just special ABM implementations. We formulate the ‘Emerging Intelligence Market Hypothesis’ to reconcile the pervasive presence of ‘noise traders’ with the near efficiency of financial markets. Finally, we note that evolutionary biology, more than physics, is now playing a growing role to inspire models of financial markets. (key issues reviews)

  7. Physics and financial economics (1776-2014): puzzles, Ising and agent-based models

    Science.gov (United States)

    Sornette, Didier

    2014-06-01

    This short review presents a selected history of the mutual fertilization between physics and economics—from Isaac Newton and Adam Smith to the present. The fundamentally different perspectives embraced in theories developed in financial economics compared with physics are dissected with the examples of the volatility smile and of the excess volatility puzzle. The role of the Ising model of phase transitions to model social and financial systems is reviewed, with the concepts of random utilities and the logit model as the analog of the Boltzmann factor in statistical physics. Recent extensions in terms of quantum decision theory are also covered. A wealth of models are discussed briefly that build on the Ising model and generalize it to account for the many stylized facts of financial markets. A summary of the relevance of the Ising model and its extensions is provided to account for financial bubbles and crashes. The review would be incomplete if it did not cover the dynamical field of agent-based models (ABMs), also known as computational economic models, of which the Ising-type models are just special ABM implementations. We formulate the ‘Emerging Intelligence Market Hypothesis’ to reconcile the pervasive presence of ‘noise traders’ with the near efficiency of financial markets. Finally, we note that evolutionary biology, more than physics, is now playing a growing role to inspire models of financial markets.

  8. A multiscale agent-based in silico model of liver fibrosis progression

    Directory of Open Access Journals (Sweden)

    Joyeeta eDutta-Moscato

    2014-05-01

    Full Text Available Chronic hepatic inflammation involves a complex interplay of inflammatory and mechanical influences, ultimately manifesting in a characteristic histopathology of liver fibrosis. We created an agent-based model (ABM of liver tissue in order to computationally examine the consequence of liver inflammation. Our Liver Fibrosis ABM (LFABM is comprised of literature-derived rules describing molecular and histopathologic aspects of inflammation and fibrosis in a section of chemically injured liver. Hepatocytes are modeled as agents within hexagonal lobules. Injury triggers an inflammatory reaction, which leads to activation of local Kupffer cells and recruitment of monocytes from circulation. Portal fibroblasts and hepatic stellate cells are activated locally by the products of inflammation. The various agents in the simulation are regulated by above-threshold concentrations of pro- and anti-inflammatory cytokines and damage-associated molecular pattern (DAMP molecules. The simulation progresses from chronic inflammation to collagen deposition, exhibiting periportal fibrosis followed by bridging fibrosis, and culminating in disruption of the regular lobular structure. The ABM exhibited key histopathologic features observed in liver sections from rats treated with carbon tetrachloride (CCl4. An in silico tension test for the hepatic lobules predicted an overall increase in tissue stiffness, in line with clinical elastography literature and published studies in CCl4-treated rats. Therapy simulations suggested differential anti-fibrotic effects of neutralizing TNF-a vs. enhancing M2 Kupffer cells. We conclude that a computational model of liver inflammation on a structural skeleton of physical forces can recapitulate key histopathologic and macroscopic properties of CCl4-injured liver. This multiscale approach linking molecular and chemomechanical stimuli enables a model that could be used to gain translationally relevant insights into live fibrosis.

  9. An Exploration into the Uses of Agent-Based Modeling to Improve Quality of Healthcare

    Science.gov (United States)

    Kanagarajah, Ashok Kay; Lindsay, Peter; Miller, Anne; Parker, David

    Healthcare is a complex adaptive system. This paper discusses, healthcare in the context of complex systems architecture and an agent based modeling framework. The paper demonstrates complications of healthcare system improvement and it's impact on patient safety, economics and workloads. Further an application of safety dynamics model proposed by Cook and Rasmussen4 is explored using a hypothetical simulation of an emergency department. By means of simulation, this paper demonstrates the nonlinear behaviors of a health service unit and its complexities; and how the safety dynamic model may be used to evaluate various aspects of healthcare. Further work is required to apply this concept in a 'real life environment' and its consequence to societal, organizational and operational levels of healthcare.

  10. Patterns of Use of an Agent-Based Model and a System Dynamics Model: The Application of Patterns of Use and the Impacts on Learning Outcomes

    Science.gov (United States)

    Thompson, Kate; Reimann, Peter

    2010-01-01

    A classification system that was developed for the use of agent-based models was applied to strategies used by school-aged students to interrogate an agent-based model and a system dynamics model. These were compared, and relationships between learning outcomes and the strategies used were also analysed. It was found that the classification system…

  11. Multiple Servers - Queue Model for Agent Based Technology in Cache Consistence Maintenance of Mobile Environment

    Directory of Open Access Journals (Sweden)

    G.Shanmugarathinam

    2013-01-01

    Full Text Available Caching is one of the important techniques in mobile computing. In caching, frequently accessed data is stored in mobile clients to avoid network traffic and improve the performance in mobile computing. In a mobile computing environment, the number of mobile users increases and requests the server for any updation, but most of the time the server is busy and the client has to wait for a long time. The cache consistency maintenance is difficult for both client and the server. This paper is proposes a technique using a queuing system consisting of one or more servers that provide services of some sort to arrive mobile hosts using agent based technology. This services mechanism of a queuing system is specified by the number of servers each server having its own queue, Agent based technology will maintain the cache consistency between the client and the server .This model saves wireless bandwidth, reduces network traffic and reduces the workload on the server. The simulation result was analyzed with previous technique and the proposed model shows significantly better performance than the earlier approach.

  12. Conceptual Agent-Based Model for Optimal Power Utilization in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Olumide S. Adewale

    2016-06-01

    Full Text Available Wireless Sensor Networks (WSNs are densely and largely deployed in a variety of environments to sense real-world events. Many approaches have been proposed for collecting sensory data in any wireless sensor networks in a flexible, reliable, and efficient manner. In this study, we design an efficient mobile agent-based model for data gathering in wireless sensor networks to achieve energy and timely collection of sensory information in the target scene. The current focus in wireless sensor networks is placed on energy optimization during data gathering, processing and transmission. Mobile Agents (MAs as a piece of a program have attracted growing research interest that travels the network from node to node to compute the local data to get useful information globally. Mobile agent’s features such as autonomy, social ability, learning, and more significantly, mobility makes it a chosen technology for information processing in wireless sensor networks and other resource constrained computing environments. The nodes of the sensors are modelled and represented by the states of a Markov chain. The nodes are further grouped into clusters to save the energy of the nodes farther away from the base station.

  13. Evaluating network analysis and agent based modeling for investigating the stability of commercial air carrier schedules

    Science.gov (United States)

    Conway, Sheila Ruth

    For a number of years, the United States Federal Government has been formulating the Next Generation Air Transportation System plans for National Airspace System improvement. These improvements attempt to address air transportation holistically, but often address individual improvements in one arena such as ground or in-flight equipment. In fact, air transportation system designers have had only limited success using traditional Operations Research and parametric modeling approaches in their analyses of innovative operations. They need a systemic methodology for modeling of safety-critical infrastructure that is comprehensive, objective, and sufficiently concrete, yet simple enough to be deployed with reasonable investment. The methodology must also be amenable to quantitative analysis so issues of system safety and stability can be rigorously addressed. The literature suggests that both agent-based models and network analysis techniques may be useful for complex system development and analysis. The purpose of this research is to evaluate these two techniques as applied to analysis of commercial air carrier schedule (route) stability in daily operations, an important component of air transportation. Airline-like routing strategies are used to educe essential elements of applying the method. Two main models are developed, one investigating the network properties of the route structure, the other an Agent-based approach. The two methods are used to predict system properties at a macro-level. These findings are compared to observed route network performance measured by adherence to a schedule to provide validation of the results. Those interested in complex system modeling are provided some indication as to when either or both of the techniques would be applicable. For aviation policy makers, the results point to a toolset capable of providing insight into the system behavior during the formative phases of development and transformation with relatively low investment

  14. Agent-based model with multi-level herding for complex financial systems

    Science.gov (United States)

    Chen, Jun-Jie; Tan, Lei; Zheng, Bo

    2015-02-01

    In complex financial systems, the sector structure and volatility clustering are respectively important features of the spatial and temporal correlations. However, the microscopic generation mechanism of the sector structure is not yet understood. Especially, how to produce these two features in one model remains challenging. We introduce a novel interaction mechanism, i.e., the multi-level herding, in constructing an agent-based model to investigate the sector structure combined with volatility clustering. According to the previous market performance, agents trade in groups, and their herding behavior comprises the herding at stock, sector and market levels. Further, we propose methods to determine the key model parameters from historical market data, rather than from statistical fitting of the results. From the simulation, we obtain the sector structure and volatility clustering, as well as the eigenvalue distribution of the cross-correlation matrix, for the New York and Hong Kong stock exchanges. These properties are in agreement with the empirical ones. Our results quantitatively reveal that the multi-level herding is the microscopic generation mechanism of the sector structure, and provide new insight into the spatio-temporal interactions in financial systems at the microscopic level.

  15. Development of Simulation System for the Disaster Evacuation Based on Multi-Agent Model Using GIS

    Institute of Scientific and Technical Information of China (English)

    Keisuke Uno; Kazuo Kashitama

    2008-01-01

    This paper presents a simulation system for the disaster evacuation based on multi-agent model considering geographical information. This system consists of three parts, the modeling for the land and buildings using GIS data, the analysis of disaster evacuation using multi-agent model, and the visualization for the numerical results using the virtual reality technique. By introducing the numerical solver of the natural disaster to the present system, it is possible to evaluate not only the damage of structure but also the dam- age of human being. Furthermore, it is possible to investigate the appropriate evacuation route by the simu- lation. The Dijkstra algorithm is used to obtain shortest route to the refuge. In addition, the visualization us- ing virtual reality technique is curried out to understand the feeling of refugee. The present system is applied to the evacuation analysis by the flood flow in urban area and is shown to be a useful tool to investigate the damage by natural disasters.

  16. An agent-based model for water management and planning in the Lake Naivasha basin, Kenya

    Science.gov (United States)

    van Oel, Pieter; Mulatu, Dawit; Odongo, Vincent; Onyando, Japheth; Becht, Robert; van der Veen, Anne

    2013-04-01

    A variety of human and natural processes influence the ecological and economic state of the Lake Naivasha basin. The ecological wealth and recent economic developments in the area are strongly connected to Lake Naivasha which supports a rich variety of flora, mammal and bird species. Many human activities depend on clean freshwater from the lake whereas recently the freshwater availability of good quality is seriously influenced by water abstractions and the use of fertilizers in agriculture. Management alternatives include those aiming at limiting water abstractions and fertilizer use. A possible way to achieve reduced use of water and fertilizers is the introduction of Payment for Environmental Services (PES) schemes. As the Lake Naivasha basin and its population have experienced increasing pressures various disputes and disagreements have arisen about the processes responsible for the problems experienced, and the effectively of management alternatives. Beside conflicts of interest and disagreements on responsibilities there are serious factual disagreements. To share scientific knowledge on the effects of the socio-ecological system processes on the Lake Naivasha basin, tools may be used that expose information at temporal and spatial scales that are meaningful to stakeholders. In this study we use a spatially-explicit agent-based modelling (ABM) approach to depict the interactions between socio-economic and natural subsystems for supporting a more sustainable governance of the river basin resources. Agents consider alternative livelihood strategies and decide to go for the one they perceive as likely to be most profitable. Agents may predict and sense the availability of resources and also can observe economic performance achieved by neighbouring agents. Results are presented at the basin and subbasin level to provide relevant knowledge to Water Resources Users Associations which are important collective forums for water management through which PES schemes

  17. Theory of agent-based market models with controlled levels of greed and anxiety

    International Nuclear Information System (INIS)

    We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.

  18. Theory of agent-based market models with controlled levels of greed and anxiety

    Science.gov (United States)

    Papadopoulos, P.; Coolen, A. C. C.

    2010-01-01

    We use generating functional analysis to study minority-game-type market models with generalized strategy valuation updates that control the psychology of agents' actions. The agents' choice between trend-following and contrarian trading, and their vigor in each, depends on the overall state of the market. Even in 'fake history' models, the theory now involves an effective overall bid process (coupled to the effective agent process) which can exhibit profound remanence effects and new phase transitions. For some models the bid process can be solved directly, others require Maxwell-construction-type approximations.

  19. Quantitative Agent Based Model of Opinion Dynamics: Polish Elections of 2015.

    Directory of Open Access Journals (Sweden)

    Pawel Sobkowicz

    Full Text Available We present results of an abstract, agent based model of opinion dynamics simulations based on the emotion/information/opinion (E/I/O approach, applied to a strongly polarized society, corresponding to the Polish political scene between 2005 and 2015. Under certain conditions the model leads to metastable coexistence of two subcommunities of comparable size (supporting the corresponding opinions-which corresponds to the bipartisan split found in Poland. Spurred by the recent breakdown of this political duopoly, which occurred in 2015, we present a model extension that describes both the long term coexistence of the two opposing opinions and a rapid, transitory change due to the appearance of a third party alternative. We provide quantitative comparison of the model with the results of polls and elections in Poland, testing the assumptions related to the modeled processes and the parameters used in the simulations. It is shown, that when the propaganda messages of the two incumbent parties differ in emotional tone, the political status quo may be unstable. The asymmetry of the emotions within the support bases of the two parties allows one of them to be 'invaded' by a newcomer third party very quickly, while the second remains immune to such invasion.

  20. Developing a multiscale, multi-resolution agent-based brain tumor model by graphics processing units

    Directory of Open Access Journals (Sweden)

    Zhang Le

    2011-12-01

    Full Text Available Abstract Multiscale agent-based modeling (MABM has been widely used to simulate Glioblastoma Multiforme (GBM and its progression. At the intracellular level, the MABM approach employs a system of ordinary differential equations to describe quantitatively specific intracellular molecular pathways that determine phenotypic switches among cells (e.g. from migration to proliferation and vice versa. At the intercellular level, MABM describes cell-cell interactions by a discrete module. At the tissue level, partial differential equations are employed to model the diffusion of chemoattractants, which are the input factors of the intracellular molecular pathway. Moreover, multiscale analysis makes it possible to explore the molecules that play important roles in determining the cellular phenotypic switches that in turn drive the whole GBM expansion. However, owing to limited computational resources, MABM is currently a theoretical biological model that uses relatively coarse grids to simulate a few cancer cells in a small slice of brain cancer tissue. In order to improve this theoretical model to simulate and predict actual GBM cancer progression in real time, a graphics processing unit (GPU-based parallel computing algorithm was developed and combined with the multi-resolution design to speed up the MABM. The simulated results demonstrated that the GPU-based, multi-resolution and multiscale approach can accelerate the previous MABM around 30-fold with relatively fine grids in a large extracellular matrix. Therefore, the new model has great potential for simulating and predicting real-time GBM progression, if real experimental data are incorporated.

  1. Quantitative Agent Based Model of Opinion Dynamics: Polish Elections of 2015.

    Science.gov (United States)

    Sobkowicz, Pawel

    2016-01-01

    We present results of an abstract, agent based model of opinion dynamics simulations based on the emotion/information/opinion (E/I/O) approach, applied to a strongly polarized society, corresponding to the Polish political scene between 2005 and 2015. Under certain conditions the model leads to metastable coexistence of two subcommunities of comparable size (supporting the corresponding opinions)-which corresponds to the bipartisan split found in Poland. Spurred by the recent breakdown of this political duopoly, which occurred in 2015, we present a model extension that describes both the long term coexistence of the two opposing opinions and a rapid, transitory change due to the appearance of a third party alternative. We provide quantitative comparison of the model with the results of polls and elections in Poland, testing the assumptions related to the modeled processes and the parameters used in the simulations. It is shown, that when the propaganda messages of the two incumbent parties differ in emotional tone, the political status quo may be unstable. The asymmetry of the emotions within the support bases of the two parties allows one of them to be 'invaded' by a newcomer third party very quickly, while the second remains immune to such invasion. PMID:27171226

  2. Catching the PHEVer: Simulating Electric Vehicle Diffusion with an Agent-Based Mixed Logit Model of Vehicle Choice

    OpenAIRE

    Maxwell Brown

    2013-01-01

    This research develops then merges two separate models to simulate electric vehicle diffusion through recreation of the Boston metropolitan statistical area vehicle market place. The first model is a mixed (random parameters) logistic regression applied to data from the US Department of Transportation's 2009 National Household Travel Survey. The second, agent-based model simulates social network interactions through which agents' vehicle choice sets are endogenously determined. Parameters fro...

  3. Diffusion dynamics and concentration of toxic materials from quantum dots-based nanotechnologies: an agent-based modeling simulation framework

    Energy Technology Data Exchange (ETDEWEB)

    Agusdinata, Datu Buyung, E-mail: bagusdinata@niu.edu; Amouie, Mahbod [Northern Illinois University, Department of Industrial & Systems Engineering and Environment, Sustainability, & Energy Institute (United States); Xu, Tao [Northern Illinois University, Department of Chemistry and Biochemistry (United States)

    2015-01-15

    Due to their favorable electrical and optical properties, quantum dots (QDs) nanostructures have found numerous applications including nanomedicine and photovoltaic cells. However, increased future production, use, and disposal of engineered QD products also raise concerns about their potential environmental impacts. The objective of this work is to establish a modeling framework for predicting the diffusion dynamics and concentration of toxic materials released from Trioctylphosphine oxide-capped CdSe. To this end, an agent-based model simulation with reaction kinetics and Brownian motion dynamics was developed. Reaction kinetics is used to model the stability of surface capping agent particularly due to oxidation process. The diffusion of toxic Cd{sup 2+} ions in aquatic environment was simulated using an adapted Brownian motion algorithm. A calibrated parameter to reflect sensitivity to reaction rate is proposed. The model output demonstrates the stochastic spatial distribution of toxic Cd{sup 2+} ions under different values of proxy environmental factor parameters. With the only chemistry considered was oxidation, the simulation was able to replicate Cd{sup 2+} ion release from Thiol-capped QDs in aerated water. The agent-based method is the first to be developed in the QDs application domain. It adds both simplicity of the solubility and rate of release of Cd{sup 2+} ions and complexity of tracking of individual atoms of Cd at the same time.

  4. Diffusion dynamics and concentration of toxic materials from quantum dots-based nanotechnologies: an agent-based modeling simulation framework

    International Nuclear Information System (INIS)

    Due to their favorable electrical and optical properties, quantum dots (QDs) nanostructures have found numerous applications including nanomedicine and photovoltaic cells. However, increased future production, use, and disposal of engineered QD products also raise concerns about their potential environmental impacts. The objective of this work is to establish a modeling framework for predicting the diffusion dynamics and concentration of toxic materials released from Trioctylphosphine oxide-capped CdSe. To this end, an agent-based model simulation with reaction kinetics and Brownian motion dynamics was developed. Reaction kinetics is used to model the stability of surface capping agent particularly due to oxidation process. The diffusion of toxic Cd2+ ions in aquatic environment was simulated using an adapted Brownian motion algorithm. A calibrated parameter to reflect sensitivity to reaction rate is proposed. The model output demonstrates the stochastic spatial distribution of toxic Cd2+ ions under different values of proxy environmental factor parameters. With the only chemistry considered was oxidation, the simulation was able to replicate Cd2+ ion release from Thiol-capped QDs in aerated water. The agent-based method is the first to be developed in the QDs application domain. It adds both simplicity of the solubility and rate of release of Cd2+ ions and complexity of tracking of individual atoms of Cd at the same time

  5. Modelling and simulation of electrical energy systems through a complex systems approach using agent-based models

    Energy Technology Data Exchange (ETDEWEB)

    Kremers, Enrique

    2013-10-01

    Complexity science aims to better understand the processes of both natural and man-made systems which are composed of many interacting entities at different scales. A disaggregated approach is proposed for simulating electricity systems, by using agent-based models coupled to continuous ones. The approach can help in acquiring a better understanding of the operation of the system itself, e.g. on emergent phenomena or scale effects; as well as in the improvement and design of future smart grids.

  6. A Simple Agent Based Model for Detecting Abnormal Event Patterns in a Distributed Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Muktikanta Sa, Manas Ranjan Nayak & Amiya Kumar Rath

    2011-08-01

    Full Text Available Wireless Sensor networks (WSN is a promising technology for current as well asfuture. There is vast use of WSN in different fields like military surveillance andtarget tracking, traffic management, weather forecasting, habitat monitoring,designing smart home, structural and seismic monitoring, etc. For successapplication of ubiquitous WSN it is important to maintain the basic security, bothfrom external and internal attacks else entire network may collapse. Maintainingsecurity in WSN network is not a simple job just like securing wireless networksbecause sensor nodes are deployed in randomize manner. Hence majorchallenges in WSN are security. In this paper we have discussed differentattacks in WSN and how these attacks are efficiently detected by using our agentbased model. Our model identifies the abnormal event pattern sensor nodes in alargely deployed distributed sensor network under a common anomaly detectionframework which will be designed by agent based learning and distributed datamining technique.

  7. Agent based model of effects of task allocation strategies in flat organizations

    Science.gov (United States)

    Sobkowicz, Pawel

    2016-09-01

    A common practice in many organizations is to pile the work on the best performers. It is easy to implement by the management and, despite the apparent injustice, appears to be working in many situations. In our work we present a simple agent based model, constructed to simulate this practice and to analyze conditions under which the overall efficiency of the organization (for example measured by the backlog of unresolved issues) breaks down, due to the cumulative effect of the individual overloads. The model confirms that the strategy mentioned above is, indeed, rational: it leads to better global results than an alternative one, using equal workload distribution among all workers. The presented analyses focus on the behavior of the organizations close to the limit of the maximum total throughput and provide results for the growth of the unprocessed backlog in several situations, as well as suggestions related to avoiding such buildup.

  8. Competition in a New Industrial Economy: Toward an Agent-Based Economic Model of Modularity

    Directory of Open Access Journals (Sweden)

    Bin-Tzong Chie

    2014-07-01

    Full Text Available When firms (conglomerates are competing, not only for the present, with a given population of customers and a fixed set of commodities or service, but also for the future, in which products are constantly evolving, what will be their competitive strategies and what will be the emerging ecology of the market? In this paper, we use the agent-based modeling of a modular economy to study the markup rate dynamics in a duopolistic setting. We find that there are multiple equilibria in the market, characterized by either a fixed point or a limit cycle. In the former case, both firms compete with the same markup rate, which is a situation similar to the familiar classic Bertrand model, except that the rate is not necessarily zero. In the latter case, both firms survive by maintaining different markup rates and different market shares.

  9. Multi-Equilibria Regulation Agent-Based Model of Opinion Dynamics in Social Networks

    Directory of Open Access Journals (Sweden)

    Andreas Koulouris

    2013-01-01

    Full Text Available This article investigates the Multiple Equilibria Regulation (MER model, i.e., an agent-based simulation model, to represent opinion dynamics in social networks. It relies on a small set of micro-prerequisites (intra-individual balance and confidence bound, leading to emergence of (nonstationary macro-outcomes. These outcomes may refer to consensus, polarization or fragmentation of opinions about taxation (e.g., congestion pricing or other policy measures, according to the way communication is structured. In contrast with other models of opinion dynamics, it allows for the impact of both the regulation of intra-personal discrepancy and the interpersonal variability of opinions on social learning and network dynamics. Several simulation experiments are presented to demonstrate, through the MER model, the role of different network structures (complete, star, cellular automata, small-world and random graphs on opinion formation dynamics and the overall evolution of the system. The findings can help to identify specific topological characteristics, such as density, number of neighbourhoods and critical nodes-agents, that affect the stability and system dynamics. This knowledge can be used to better organize the information diffusion and learning in the community, enhance the predictability of outcomes and manage possible conflicts. It is shown that a small-world organization, which depicts more realistic aspects of real-life and virtual social systems, provides increased predictability and stability towards a less fragmented and more manageable grouping of opinions, compared to random networks. Such macro-level organizations may be enhanced with use of web-based technologies to increase the density of communication and public acceptability of policy measures.

  10. Comparing Simulation Output Accuracy of Discrete Event and Agent Based Models: A Quantitive Approach

    CERN Document Server

    Majid, Mazlina Abdul; Siebers, Peer-Olaf

    2010-01-01

    In our research we investigate the output accuracy of discrete event simulation models and agent based simulation models when studying human centric complex systems. In this paper we focus on human reactive behaviour as it is possible in both modelling approaches to implement human reactive behaviour in the model by using standard methods. As a case study we have chosen the retail sector, and here in particular the operations of the fitting room in the women wear department of a large UK department store. In our case study we looked at ways of determining the efficiency of implementing new management policies for the fitting room operation through modelling the reactive behaviour of staff and customers of the department. First, we have carried out a validation experiment in which we compared the results from our models to the performance of the real system. This experiment also allowed us to establish differences in output accuracy between the two modelling methids. In a second step a multi-scenario experimen...

  11. Multi-agent control system with information fusion based comfort model for smart buildings

    International Nuclear Information System (INIS)

    Highlights: ► Proposed a model to manage indoor energy and comfort for smart buildings. ► Developed a control system to maximize comfort with minimum energy consumption. ► Information fusion with ordered weighted averaging aggregation is used. ► Multi-agent technology and heuristic intelligent optimization are deployed in developing the control system. -- Abstract: From the perspective of system control, a smart and green building is a large-scale dynamic system with high complexity and a huge amount of information. Proper combination of the available information and effective control of the overall building system turns out to be a big challenge. In this study, we proposed a building indoor energy and comfort management model based on information fusion using ordered weighted averaging (OWA) aggregation. A multi-agent control system with heuristic intelligent optimization is developed to achieve a high level of comfort with the minimum power consumption. Case studies and simulation results are presented and discussed in this paper.

  12. BSim: an agent-based tool for modeling bacterial populations in systems and synthetic biology.

    Directory of Open Access Journals (Sweden)

    Thomas E Gorochowski

    Full Text Available Large-scale collective behaviors such as synchronization and coordination spontaneously arise in many bacterial populations. With systems biology attempting to understand these phenomena, and synthetic biology opening up the possibility of engineering them for our own benefit, there is growing interest in how bacterial populations are best modeled. Here we introduce BSim, a highly flexible agent-based computational tool for analyzing the relationships between single-cell dynamics and population level features. BSim includes reference implementations of many bacterial traits to enable the quick development of new models partially built from existing ones. Unlike existing modeling tools, BSim fully considers spatial aspects of a model allowing for the description of intricate micro-scale structures, enabling the modeling of bacterial behavior in more realistic three-dimensional, complex environments. The new opportunities that BSim opens are illustrated through several diverse examples covering: spatial multicellular computing, modeling complex environments, population dynamics of the lac operon, and the synchronization of genetic oscillators. BSim is open source software that is freely available from http://bsim-bccs.sf.net and distributed under the Open Source Initiative (OSI recognized MIT license. Developer documentation and a wide range of example simulations are also available from the website. BSim requires Java version 1.6 or higher.

  13. BSim: an agent-based tool for modeling bacterial populations in systems and synthetic biology.

    Science.gov (United States)

    Gorochowski, Thomas E; Matyjaszkiewicz, Antoni; Todd, Thomas; Oak, Neeraj; Kowalska, Kira; Reid, Stephen; Tsaneva-Atanasova, Krasimira T; Savery, Nigel J; Grierson, Claire S; di Bernardo, Mario

    2012-01-01

    Large-scale collective behaviors such as synchronization and coordination spontaneously arise in many bacterial populations. With systems biology attempting to understand these phenomena, and synthetic biology opening up the possibility of engineering them for our own benefit, there is growing interest in how bacterial populations are best modeled. Here we introduce BSim, a highly flexible agent-based computational tool for analyzing the relationships between single-cell dynamics and population level features. BSim includes reference implementations of many bacterial traits to enable the quick development of new models partially built from existing ones. Unlike existing modeling tools, BSim fully considers spatial aspects of a model allowing for the description of intricate micro-scale structures, enabling the modeling of bacterial behavior in more realistic three-dimensional, complex environments. The new opportunities that BSim opens are illustrated through several diverse examples covering: spatial multicellular computing, modeling complex environments, population dynamics of the lac operon, and the synchronization of genetic oscillators. BSim is open source software that is freely available from http://bsim-bccs.sf.net and distributed under the Open Source Initiative (OSI) recognized MIT license. Developer documentation and a wide range of example simulations are also available from the website. BSim requires Java version 1.6 or higher. PMID:22936991

  14. Performance-Based Design for Large Crowd Venue Control Using a Multi-Agent Model

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qingsong; ZHAO Guomin; LIU Jinlan

    2009-01-01

    Performance-based design is more holistic and flexible than prescriptive design for providing safety in large complex buildings. Here, a multi-agent method to model the egress pattems of evacuees is combined with a microscopic pedestrian simulation model used to analyze the forces between individuals in a densely populated enclosed space in a crowd crushing and trampling analysis (CroC&Ts). The system is used to model egress pattems in a typical crowd evacuation simulation. The simulations indicate that some individuals will die from crushing in 2 m and 4 m wide exits in emergencies. The simulations also show that the fatality probability increases when barriers obstacled the path and when the egress distances were lar-ger. The simulations validate the conclusions of the stranded crowd model (SCM) and provide quantitative predictions of the crowd crushing and trampling risk. Therefore, the CroC&Ts can provide performance-based egress designs for large pubic buildings and improve crowd safety management and emergency planning.

  15. Coupled agent-based and finite-element models for predicting scar structure following myocardial infarction.

    Science.gov (United States)

    Rouillard, Andrew D; Holmes, Jeffrey W

    2014-08-01

    Following myocardial infarction, damaged muscle is gradually replaced by collagenous scar tissue. The structural and mechanical properties of the scar are critical determinants of heart function, as well as the risk of serious post-infarction complications such as infarct rupture, infarct expansion, and progression to dilated heart failure. A number of therapeutic approaches currently under development aim to alter infarct mechanics in order to reduce complications, such as implantation of mechanical restraint devices, polymer injection, and peri-infarct pacing. Because mechanical stimuli regulate scar remodeling, the long-term consequences of therapies that alter infarct mechanics must be carefully considered. Computational models have the potential to greatly improve our ability to understand and predict how such therapies alter heart structure, mechanics, and function over time. Toward this end, we developed a straightforward method for coupling an agent-based model of scar formation to a finite-element model of tissue mechanics, creating a multi-scale model that captures the dynamic interplay between mechanical loading, scar deformation, and scar material properties. The agent-based component of the coupled model predicts how fibroblasts integrate local chemical, structural, and mechanical cues as they deposit and remodel collagen, while the finite-element component predicts local mechanics at any time point given the current collagen fiber structure and applied loads. We used the coupled model to explore the balance between increasing stiffness due to collagen deposition and increasing wall stress due to infarct thinning and left ventricular dilation during the normal time course of healing in myocardial infarcts, as well as the negative feedback between strain anisotropy and the structural anisotropy it promotes in healing scar. The coupled model reproduced the observed evolution of both collagen fiber structure and regional deformation following coronary

  16. A Unified Multiscale Field/Network/Agent Based Modeling Framework for Human and Ecological Health Risk Analysis

    OpenAIRE

    Georgopoulos, Panos G.; Isukapalli, Sastry S.

    2009-01-01

    A conceptual framework is presented for multiscale field/network/agent-based modeling to support human and ecological health risk assessments. This framework is based on the representation of environmental dynamics in terms of interacting networks, agents that move across different networks, fields representing spatiotemporal distributions of physical properties, rules governing constraints and interactions, and actors that make decisions affecting the state of the system. Different determini...

  17. A Spatial-Dynamic Agent-based Model of Energy Crop Introduction in Jiangsu province, China

    Science.gov (United States)

    Shu, K.; Schneider, U. A.; Scheffran, J.

    2012-12-01

    Bioenergy, as one promising option to replace a fraction of conventional fossil fuels and lower net greenhouse gas emissions, has gained many countries', in particular developing ones' attention. Their focus is mainly on the design of efficient bioenergy utilization pathways which adapt to both local geographic features and economic conditions. The establishment of a biomass production sector would be the first and pivotal component in the whole industrial chain. Several existing studies have estimated the global biomass for energy potential but arrived at very different results. One reason for the large uncertainty of biomass potential may be ascribed to the diverse nature of biomass leading to different estimates in different circumstances. Therefore, specific research at the local level is essential. Following this thought, our research conducted in the Jiangsu province, a representative region in China, will explore the spatial distribution of biomass production. The employed methodology can also be applied to other locations both in China and similar developing countries if model parameters are adequately adjusted. In this study, we analyze the local situation in the Jiangsu province focusing on the selection of new energy crops, since the cultivation of dedicated crop for energy use is still in experimental phase. We also examine the land use conflict which is especially relevant to China with more than 1.3 billion people and a severe burden on food supply. We develop an agent-based model to find the optimal spatial distribution of biomass (SDA-SDB) in Jiangsu province. Compromising data accessibility and heterogeneity of environmental factors across the province, we resolve our model at county level and consider the aggregated farming community in one county as a single agent. The aim of SDA-SDB is to simulate farmers' decision process of allocating land to either food or energy crops facing limited resources and political targets for bioenergy development

  18. Agent based models of language competition: macroscopic descriptions and order-disorder transitions

    Science.gov (United States)

    Vazquez, F.; Castelló, X.; San Miguel, M.

    2010-04-01

    We investigate the dynamics of two agent based models of language competition. In the first model, each individual can be in one of two possible states, either using language X or language Y, while the second model incorporates a third state XY, representing individuals that use both languages (bilinguals). We analyze the models on complex networks and two-dimensional square lattices by analytical and numerical methods, and show that they exhibit a transition from one-language dominance to language coexistence. We find that the coexistence of languages is more difficult to maintain in the bilinguals model, where the presence of bilinguals facilitates the ultimate dominance of one of the two languages. A stability analysis reveals that the coexistence is more unlikely to happen in poorly connected than in fully connected networks, and that the dominance of just one language is enhanced as the connectivity decreases. This dominance effect is even stronger in a two-dimensional space, where domain coarsening tends to drive the system towards language consensus.

  19. Agent Based Models of Language Competition: Macroscopic descriptions and Order-Disorder transitions

    CERN Document Server

    Vazquez, F; Miguel, M San

    2010-01-01

    We investigate the dynamics of two agent based models of language competition. In the first model, each individual can be in one of two possible states, either using language $X$ or language $Y$, while the second model incorporates a third state XY, representing individuals that use both languages (bilinguals). We analyze the models on complex networks and two-dimensional square lattices by analytical and numerical methods, and show that they exhibit a transition from one-language dominance to language coexistence. We find that the coexistence of languages is more difficult to maintain in the Bilinguals model, where the presence of bilinguals in use facilitates the ultimate dominance of one of the two languages. A stability analysis reveals that the coexistence is more unlikely to happen in poorly-connected than in fully connected networks, and that the dominance of only one language is enhanced as the connectivity decreases. This dominance effect is even stronger in a two-dimensional space, where domain coar...

  20. Agent based models of language competition: macroscopic descriptions and order–disorder transitions

    International Nuclear Information System (INIS)

    We investigate the dynamics of two agent based models of language competition. In the first model, each individual can be in one of two possible states, either using language X or language Y, while the second model incorporates a third state XY, representing individuals that use both languages (bilinguals). We analyze the models on complex networks and two-dimensional square lattices by analytical and numerical methods, and show that they exhibit a transition from one-language dominance to language coexistence. We find that the coexistence of languages is more difficult to maintain in the bilinguals model, where the presence of bilinguals facilitates the ultimate dominance of one of the two languages. A stability analysis reveals that the coexistence is more unlikely to happen in poorly connected than in fully connected networks, and that the dominance of just one language is enhanced as the connectivity decreases. This dominance effect is even stronger in a two-dimensional space, where domain coarsening tends to drive the system towards language consensus

  1. On religion and language evolutions seen through mathematical and agent based models

    CERN Document Server

    Ausloos, M

    2011-01-01

    (shortened version) Religions and languages are social variables, like age, sex, wealth or political opinions, to be studied like any other organizational parameter. In fact, religiosity is one of the most important sociological aspects of populations. Languages are also a characteristics of the human kind. New religions, new languages appear though others disappear. All religions and languages evolve when they adapt to the society developments. On the other hand, the number of adherents of a given religion, the number of persons speaking a language is not fixed. Several questions can be raised. E.g. from a macroscopic point of view : How many religions/languages exist at a given time? What is their distribution? What is their life time? How do they evolve?. From a microscopic view point: can one invent agent based models to describe macroscopic aspects? Does it exist simple evolution equations? It is intuitively accepted, but also found through from statistical analysis of the frequency distribution that an ...

  2. Computational Research on Mobile Pastoralism Using Agent-Based Modeling and Satellite Imagery

    Science.gov (United States)

    Sakamoto, Takuto

    2016-01-01

    Dryland pastoralism has long attracted considerable attention from researchers in diverse fields. However, rigorous formal study is made difficult by the high level of mobility of pastoralists as well as by the sizable spatio-temporal variability of their environment. This article presents a new computational approach for studying mobile pastoralism that overcomes these issues. Combining multi-temporal satellite images and agent-based modeling allows a comprehensive examination of pastoral resource access over a realistic dryland landscape with unpredictable ecological dynamics. The article demonstrates the analytical potential of this approach through its application to mobile pastoralism in northeast Nigeria. Employing more than 100 satellite images of the area, extensive simulations are conducted under a wide array of circumstances, including different land-use constraints. The simulation results reveal complex dependencies of pastoral resource access on these circumstances along with persistent patterns of seasonal land use observed at the macro level. PMID:26963526

  3. Epidermal homeostasis control in an off-lattice agent-based model

    CERN Document Server

    Schaller, G; Schaller, Gernot; Meyer-Hermann, Michael

    2005-01-01

    We apply an improved version of a previously introduced off-lattice agent-based model to the steady-state flow equilibrium of skin. The dynamics of cells is determined by conservative and drag forces, supplemented with delta-correlated random forces. Cellular adjacency is detected by a weighted Delaunay triangulation. We analyze a simple control mechanism: The cell cycle time of keratinocytes is controlled by a diffusible substance provided by the dermis, in particular we consider the local water concentration. This concentration is calculated from a diffusion equation with time-dependent boundary conditions and varying diffusion coefficients. It turns out that this simple control mechanism suffices to explain several characteristics of epidermal growth. The dynamics of a nutrient is also taken into account by a reaction-diffusion equation. In addition, we ask the simple question of how melanoma with decreased basal adhesion manage to persist within the steady-state flow-equilibrium of the skin. It turns out ...

  4. Computational Research on Mobile Pastoralism Using Agent-Based Modeling and Satellite Imagery.

    Science.gov (United States)

    Sakamoto, Takuto

    2016-01-01

    Dryland pastoralism has long attracted considerable attention from researchers in diverse fields. However, rigorous formal study is made difficult by the high level of mobility of pastoralists as well as by the sizable spatio-temporal variability of their environment. This article presents a new computational approach for studying mobile pastoralism that overcomes these issues. Combining multi-temporal satellite images and agent-based modeling allows a comprehensive examination of pastoral resource access over a realistic dryland landscape with unpredictable ecological dynamics. The article demonstrates the analytical potential of this approach through its application to mobile pastoralism in northeast Nigeria. Employing more than 100 satellite images of the area, extensive simulations are conducted under a wide array of circumstances, including different land-use constraints. The simulation results reveal complex dependencies of pastoral resource access on these circumstances along with persistent patterns of seasonal land use observed at the macro level. PMID:26963526

  5. Agent-based models for the emergence and evolution of grammar.

    Science.gov (United States)

    Steels, Luc

    2016-08-19

    Human languages are extraordinarily complex adaptive systems. They feature intricate hierarchical sound structures, are able to express elaborate meanings and use sophisticated syntactic and semantic structures to relate sound to meaning. What are the cognitive mechanisms that speakers and listeners need to create and sustain such a remarkable system? What is the collective evolutionary dynamics that allows a language to self-organize, become more complex and adapt to changing challenges in expressive power? This paper focuses on grammar. It presents a basic cycle observed in the historical language record, whereby meanings move from lexical to syntactic and then to a morphological mode of expression before returning to a lexical mode, and discusses how we can discover and validate mechanisms that can cause these shifts using agent-based models.This article is part of the themed issue 'The major synthetic evolutionary transitions'. PMID:27431525

  6. Computational Research on Mobile Pastoralism Using Agent-Based Modeling and Satellite Imagery.

    Directory of Open Access Journals (Sweden)

    Takuto Sakamoto

    Full Text Available Dryland pastoralism has long attracted considerable attention from researchers in diverse fields. However, rigorous formal study is made difficult by the high level of mobility of pastoralists as well as by the sizable spatio-temporal variability of their environment. This article presents a new computational approach for studying mobile pastoralism that overcomes these issues. Combining multi-temporal satellite images and agent-based modeling allows a comprehensive examination of pastoral resource access over a realistic dryland landscape with unpredictable ecological dynamics. The article demonstrates the analytical potential of this approach through its application to mobile pastoralism in northeast Nigeria. Employing more than 100 satellite images of the area, extensive simulations are conducted under a wide array of circumstances, including different land-use constraints. The simulation results reveal complex dependencies of pastoral resource access on these circumstances along with persistent patterns of seasonal land use observed at the macro level.

  7. Testing an agent-based model of bacterial cell motility: How nutrient concentration affects speed distribution

    Science.gov (United States)

    Garcia, V.; Birbaumer, M.; Schweitzer, F.

    2011-08-01

    We revisit a recently proposed agent-based model of active biological motion and compare its predictions with own experimental findings for the speed distribution of bacterial cells, Salmonella typhimurium. Agents move according to a stochastic dynamics and use energy stored in an internal depot for metabolism and active motion. We discuss different assumptions of how the conversion from internal to kinetic energy d( v) may depend on the actual speed, to conclude that d 2 v ξ with either ξ = 2 or 1 speed distribution of bacteria which were obtained in media of different nutrient concentration and at different times. We find that both hypotheses are in line with the experimental observations, with ξ between 1.67 and 2.0. Regarding the influence of a higher nutrient concentration, we conclude that the take-up of energy by bacterial cells is indeed increased. But this energy is not used to increase the speed, with 40 μm/s as the most probable value of the speed distribution, but is rather spend on metabolism and growth.

  8. Coupling Agent-Based and Groundwater Modeling to Explore Demand Management Strategies for Shared Resources

    Science.gov (United States)

    Al-Amin, S.

    2015-12-01

    Municipal water demands in growing population centers in the arid southwest US are typically met through increased groundwater withdrawals. Hydro-climatic uncertainties attributed to climate change and land use conversions may also alter demands and impact the replenishment of groundwater supply. Groundwater aquifers are not necessarily confined within municipal and management boundaries, and multiple diverse agencies may manage a shared resource in a decentralized approach, based on individual concerns and resources. The interactions among water managers, consumers, and the environment influence the performance of local management strategies and regional groundwater resources. This research couples an agent-based modeling (ABM) framework and a groundwater model to analyze the effects of different management approaches on shared groundwater resources. The ABM captures the dynamic interactions between household-level consumers and policy makers to simulate water demands under climate change and population growth uncertainties. The groundwater model is used to analyze the relative effects of management approaches on reducing demands and replenishing groundwater resources. The framework is applied for municipalities located in the Verde River Basin, Arizona that withdraw groundwater from the Verde Formation-Basin Fill-Carbonate aquifer system. Insights gained through this simulation study can be used to guide groundwater policy-making under changing hydro-climatic scenarios for a long-term planning horizon.

  9. An Agent-based Strategy for Deploying Analysis Models into Specification and Design for Distributed APS Systems

    CERN Document Server

    de Santa-Eulalia, Luis Antonio; Frayret, Jean-Marc

    2011-01-01

    Despite the extensive use of the agent technology in the Supply Chain Management field, its integration with Advanced Planning and Scheduling (APS) tools still represents a promising field with several open research questions. Specifically, the literature falls short in providing an integrated framework to analyze, specify, design and implement simulation experiments covering the whole simulation cycle. Thus, this paper proposes an agent-based strategy to convert the 'analysis' models into 'specification' and 'design' models combining two existing methodologies proposed in the literature. The first one is a recent and unique approach dedicated to the 'analysis' of agent-based APS systems. The second one is a well-established methodological framework to 'specify' and 'design' agent-based supply chain systems. The proposed conversion strategy is original and is the first one allowing simulation analysts to integrate the whole simulation development process in the domain of distributed APS.

  10. The Influence of Seasonal Forecast Accuracy on Farmer Behavior: An Agent-Based Modeling Approach

    Science.gov (United States)

    Jacobi, J. H.; Nay, J.; Gilligan, J. M.

    2013-12-01

    Seasonal climates dictate the livelihoods of farmers in developing countries. While farmers in developed countries often have seasonal forecasts on which to base their cropping decisions, developing world farmers usually make plans for the season without such information. Climate change increases the seasonal uncertainty, making things more difficult for farmers. Providing seasonal forecasts to these farmers is seen as a way to help buffer these typically marginal groups from the effects of climate change, though how to do so and the efficacy of such an effort is still uncertain. In Sri Lanka, an effort is underway to provide such forecasts to farmers. The accuracy of these forecasts is likely to have large impacts on how farmers accept and respond to the information they receive. We present an agent-based model to explore how the accuracy of seasonal rainfall forecasts affects the growing decisions and behavior of farmers in Sri Lanka. Using a decision function based on prospect theory, this model simulates farmers' behavior in the face of a wet, dry, or normal forecast. Farmers can either choose to grow paddy rice or plant a cash crop. Prospect theory is used to evaluate outcomes of the growing season; the farmer's memory of the level of success under a certain set of conditions affects next season's decision. Results from this study have implications for policy makers and seasonal forecasters.

  11. Exploring the polycentric city with multi-worker households: an agent-based microeconomic model

    OpenAIRE

    LEMOY, Rémi; Raux, Charles; Jensen, Pablo

    2013-01-01

    We propose an agent-based dynamics which leads an urban system to the standard equilibrium of the Alonso, Muth, Mills (AMM) framework. Starting for instance from a random initialization, agents move and bid for land, performing a kind of local search and finally leading the system to equilibrium rent, density and land use. Agreement with continuous analytical results is only limited by the discreteness of simulations. We then study polycentrism in cities with this tool. Two job centers are in...

  12. An agent-based model of cellular dynamics and circadian variability in human endotoxemia.

    Directory of Open Access Journals (Sweden)

    Tung T Nguyen

    Full Text Available As cellular variability and circadian rhythmicity play critical roles in immune and inflammatory responses, we present in this study an agent-based model of human endotoxemia to examine the interplay between circadian controls, cellular variability and stochastic dynamics of inflammatory cytokines. The model is qualitatively validated by its ability to reproduce circadian dynamics of inflammatory mediators and critical inflammatory responses after endotoxin administration in vivo. Novel computational concepts are proposed to characterize the cellular variability and synchronization of inflammatory cytokines in a population of heterogeneous leukocytes. Our results suggest that there is a decrease in cell-to-cell variability of inflammatory cytokines while their synchronization is increased after endotoxin challenge. Model parameters that are responsible for IκB production stimulated by NFκB activation and for the production of anti-inflammatory cytokines have large impacts on system behaviors. Additionally, examining time-dependent systemic responses revealed that the system is least vulnerable to endotoxin in the early morning and most vulnerable around midnight. Although much remains to be explored, proposed computational concepts and the model we have pioneered will provide important insights for future investigations and extensions, especially for single-cell studies to discover how cellular variability contributes to clinical implications.

  13. A Watershed-Scale Agent-Based Model Incorporating Agent Learning and Interaction of Farmers' Decisions Subject to Carbon and Miscanthus Prices

    Science.gov (United States)

    Ng, T.; Eheart, J.; Cai, X.; Braden, J. B.

    2010-12-01

    Agricultural watersheds are coupled human-natural systems where the land use decisions of human agents (farmers) affect surface water quality, and in turn, are affected by the weather and yields. The reliable modeling of such systems requires an approach that considers both the human and natural aspects. Agent-based modeling (ABM), representing the human aspect, coupled with hydrologic modeling, representing the natural aspect, is one such approach. ABM is a relatively new modeling paradigm that formulates the system from the perspectives of the individual agents, i.e., each agent is modeled as a discrete autonomous entity with distinct goals and actions. The primary objective of this study is to demonstrate the applicability of this approach to agricultural watershed management. This is done using a semi-hypothetical case study of farmers in the Salt Creek watershed in East-Central Illinois under the influence markets for carbon and second-generation bioenergy crop (specifically, miscanthus). An agent-based model of the system is developed and linked to a hydrologic model of the watershed. The former is based on fundamental economic and mathematical programming principles, while the latter is based on the Soil and Water Assessment Tool (SWAT). Carbon and second-generation bioenergy crop markets are of interest here due to climate change and energy independence concerns. The agent-based model is applied to fifty hypothetical heterogeneous farmers. The farmers' decisions depend on their perceptions of future conditions. Those perceptions are updated, according to a pre-defined algorithm, as the farmers make new observations of prices, costs, yields and the weather with time. The perceptions are also updated as the farmers interact with each other as they share new information on initially unfamiliar activities (e.g., carbon trading, miscanthus cultivation). The updating algorithm is set differently for different farmers such that each is unique in his processing of

  14. Evaluation of oxime efficacy in nerve agent poisoning: Development of a kinetic-based dynamic model

    International Nuclear Information System (INIS)

    The widespread use of organophosphorus compounds (OP) as pesticides and the repeated misuse of highly toxic OP as chemical warfare agents (nerve agents) emphasize the necessity for the development of effective medical countermeasures. Standard treatment with atropine and the established acetylcholinesterase (AChE) reactivators, obidoxime and pralidoxime, is considered to be ineffective with certain nerve agents due to low oxime effectiveness. From obvious ethical reasons only animal experiments can be used to evaluate new oximes as nerve agent antidotes. However, the extrapolation of data from animal to humans is hampered by marked species differences. Since reactivation of OP-inhibited AChE is considered to be the main mechanism of action of oximes, human erythrocyte AChE can be exploited to test the efficacy of new oximes. By combining enzyme kinetics (inhibition, reactivation, aging) with OP toxicokinetics and oxime pharmacokinetics a dynamic in vitro model was developed which allows the calculation of AChE activities at different scenarios. This model was validated with data from pesticide-poisoned patients and simulations were performed for intravenous and percutaneous nerve agent exposure and intramuscular oxime treatment using published data. The model presented may serve as a tool for defining effective oxime concentrations and for optimizing oxime treatment. In addition, this model can be useful for the development of meaningful therapeutic animal models

  15. Optimizing the structure of the natural gas market using an agent-based modeling framework

    International Nuclear Information System (INIS)

    The overall research question guiding this study is as follows: what is the optimal structure of the natural gas market, considering both the degrees of affordability and supply security resulting from this structure? The sub-questions are: How can the concepts of supply security and affordability be usefully defined? (Chapter 2); What should a modeling framework for analyzing the natural gas market with regard to these concepts look like? (Chapters 3 and 4); What general conclusions can be drawn on the basis of this framework? (Chapter 5); What is the effect of liberalization on the Dutch natural gas market? (Chapter 6); What are the possible effects of current trends unfolding in the Dutch natural gas market? (Chapter 7). The framework constructed in this study implicitly contains the necessary elements for deriving a sustainability indicator too. However, to limit the scope of the study, sustainability will not be analyzed explicitly. Chapter 2 provides an introductory description of the natural gas market. Starting from a description of the natural gas value chain, the process of liberalization is described as a change in the organization of the value chain. In addition, the concepts of affordability and supply security are discussed and appropriate quantitative indicators for both objectives are identified. In Chapter 3, a survey of existing gas market models is performed. On the basis of this survey, a classification system for natural gas market models is developed. Furthermore, the characteristics of a modeling framework fit for the purpose of this study are derived. In Chapter 4, a general, quantitative framework for natural gas market modeling is developed on the basis of agent-based computational economics. The model's structure, its dynamics, output and data requirements are described. Furthermore, the properties of each agent are explored, and the possibilities for model verification and validation are outlined. Chapter 5 provides a number of

  16. Linking Bayesian and Agent-Based Models to Simulate Complex Social-Ecological Systems in the Sonoran Desert

    Science.gov (United States)

    Pope, A.; Gimblett, R.

    2013-12-01

    Interdependencies of ecologic, hydrologic, and social systems challenge traditional approaches to natural resource management in semi-arid regions. As a complex social-ecological system, water demands in the Sonoran Desert from agricultural and urban users often conflicts with water needs for its ecologically-significant riparian corridors. To explore this system, we developed an agent-based model to simulate complex feedbacks between human decisions and environmental conditions. Cognitive mapping in conjunction with stakeholder participation produced a Bayesian model of conditional probabilities of local human decision-making processes resulting to changes in water demand. Probabilities created in the Bayesian model were incorporated into the agent-based model, so that each agent had a unique probability to make a positive decision based on its perceived environment at each point in time and space. By using a Bayesian approach, uncertainty in the human decision-making process could be incorporated. The spatially-explicit agent-based model simulated changes in depth-to-groundwater by well pumping based on an agent's water demand. Depth-to-groundwater was then used as an indicator of unique vegetation guilds within the riparian corridor. Each vegetation guild provides varying levels of ecosystem services, the changes of which, along with changes in depth-to-groundwater, feedback to influence agent behavior. Using this modeling approach allowed us to examine resilience of semi-arid riparian corridors and agent behavior under various scenarios. The insight provided by the model contributes to understanding how specific interventions may alter the complex social-ecological system in the future.

  17. Intending the Unintended: The Act of Building Agent-based Models as a Regular Source of Knowledge Generation

    Directory of Open Access Journals (Sweden)

    Mitali Ayyangar

    2007-10-01

    Full Text Available Poverty is a complex issue that is rarely conducive to analysis in laboratory or field experiments. Effective interventions that aim to decrease or eliminate poverty require an understanding of the intricate web of associated social issues. The need for this increased comprehension necessitates the use of alternative robust means of analysis: one such being agent-based modelling. The strengths of agent-based modelling to disaggregate complex social behaviours and understand them are well known. However, while people have explored how the modelling process can prove to be fruitful, the usually unintended insight gained and the knowledge engendered during the model design process goes largely unnoticed. In this paper, we aspire to show precisely how the model building process is critical in leading to unintended knowledge generation for modellers by drawing from three US based examples where agent-based modelling was used to aid research into the effects of interventions that address poverty and human development through programs and issues facing low-income families. With these examples, we illustrate some of the means to harness new knowledge generated. In our discussion, we also highlight the advantageous nature of agent-based model design as an independent source of knowledge generation.

  18. New methods for energy market modelling : Proceedings of the First European Workshop on Energy Market Modelling using Agent-Based Computational Economics

    OpenAIRE

    Möst, D.; Fichtner, W.; Ragwitz, M.; Veit, D. [Hrsg.

    2008-01-01

    A growing number of researchers have developed agent-based models to simulate the development of liberalized energy markets. As the field of energy market modelling with agent-based computational economics is very heterogeneous, the overview in this book might help interested researchers to get a sense for the different modelling approaches and to learn about the potential of this valuable modelling approach in different fields of the energy market.

  19. Agents modeling agents in information economies

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, J.M.; Durfee, E.H. [Univ. of Michigan, Ann Arbor, MI (United States)

    1996-12-31

    Our goal is to design and build agents that act intelligently when placed in an agent-based information economy, where agents buy and sell services (e.g. thesaurus, search, task planning services, etc.). The economy we are working in is the University of Michigan Digital Library (UMDL), a large scale multidisciplinary effort to build an infrastructure for the delivery of library services. In contrast with a typical economy, an information economy deals in goods and services that are often derived from unique sources (authors, analysts, etc.), so that many goods and services are not interchangeable. Also, the cost of replicating and transporting goods is usually negligible, and the quality of goods and services is difficult to measure objectively: even two sources with essentially the same information might appeal to different audiences. Thus, each agent has its own assessment of the quality of goods and services delivered.

  20. An Agent-based Strategy for Deploying Analysis Models into Specification and Design for Distributed APS Systems

    OpenAIRE

    Luis Antonio Santa-Eulalia; Sophie D'Amours; Jean-Marc Frayret

    2011-01-01

    Despite the extensive use of the agent technology in the Supply Chain Management field, its integration with Advanced Planning and Scheduling (APS) tools still represents a promising field with several open research questions. Specifically, the literature falls short in providing an integrated framework to analyze, specify, design and implement simulation experiments covering the whole simulation cycle. Thus, this paper proposes an agent-based strategy to convert the 'analysis' models into 's...

  1. An operational epidemiological model for calibrating agent-based simulations of pandemic influenza outbreaks.

    Science.gov (United States)

    Prieto, D; Das, T K

    2016-03-01

    Uncertainty of pandemic influenza viruses continue to cause major preparedness challenges for public health policymakers. Decisions to mitigate influenza outbreaks often involve tradeoff between the social costs of interventions (e.g., school closure) and the cost of uncontrolled spread of the virus. To achieve a balance, policymakers must assess the impact of mitigation strategies once an outbreak begins and the virus characteristics are known. Agent-based (AB) simulation is a useful tool for building highly granular disease spread models incorporating the epidemiological features of the virus as well as the demographic and social behavioral attributes of tens of millions of affected people. Such disease spread models provide excellent basis on which various mitigation strategies can be tested, before they are adopted and implemented by the policymakers. However, to serve as a testbed for the mitigation strategies, the AB simulation models must be operational. A critical requirement for operational AB models is that they are amenable for quick and simple calibration. The calibration process works as follows: the AB model accepts information available from the field and uses those to update its parameters such that some of its outputs in turn replicate the field data. In this paper, we present our epidemiological model based calibration methodology that has a low computational complexity and is easy to interpret. Our model accepts a field estimate of the basic reproduction number, and then uses it to update (calibrate) the infection probabilities in a way that its effect combined with the effects of the given virus epidemiology, demographics, and social behavior results in an infection pattern yielding a similar value of the basic reproduction number. We evaluate the accuracy of the calibration methodology by applying it for an AB simulation model mimicking a regional outbreak in the US. The calibrated model is shown to yield infection patterns closely replicating

  2. The critical properties of the agent-based model with environmental-economic interactions

    CERN Document Server

    Kuscsik, Z; Horváth, D

    2007-01-01

    The steady-state and nonequilibrium properties of the model of environmental-economic interactions are studied. The interacting heterogeneous agents are simulated on the platform of the emission dynamics of cellular automaton. The model possess the discontinuous transition between the safe and catastrophic ecology. Right at the critical line, the broad-scale power-law distributions of emission rates have been identified. Their relationship to Zipf's law and models of self-organized criticality is discussed.

  3. A risk assessment example for soil invertebrates using spatially explicit agent-based models.

    Science.gov (United States)

    Reed, Melissa; Alvarez, Tania; Chelinho, Sónia; Forbes, Valery; Johnston, Alice; Meli, Mattia; Voss, Frank; Pastorok, Rob

    2016-01-01

    Current risk assessment methods for measuring the toxicity of plant protection products (PPPs) on soil invertebrates use standardized laboratory conditions to determine acute effects on mortality and sublethal effects on reproduction. If an unacceptable risk is identified at the lower tier, population-level effects are assessed using semifield and field trials at a higher tier because modeling methods for extrapolating available lower-tier information to population effects have not yet been implemented. Field trials are expensive, time consuming, and cannot be applied to variable landscape scenarios. Mechanistic modeling of the toxicological effects of PPPs on individuals and their responses combined with simulation of population-level response shows great potential in fulfilling such a need, aiding ecologically informed extrapolation. Here, we introduce and demonstrate the potential of 2 population models for ubiquitous soil invertebrates (collembolans and earthworms) as refinement options in current risk assessment. Both are spatially explicit agent-based models (ABMs), incorporating individual and landscape variability. The models were used to provide refined risk assessments for different application scenarios of a hypothetical pesticide applied to potato crops (full-field spray onto the soil surface [termed "overall"], in-furrow, and soil-incorporated pesticide applications). In the refined risk assessment, the population models suggest that soil invertebrate populations would likely recover within 1 year after pesticide application, regardless of application method. The population modeling for both soil organisms also illustrated that a lower predicted average environmental concentration in soil (PECsoil) could potentially lead to greater effects at the population level, depending on the spatial heterogeneity of the pesticide and the behavior of the soil organisms. Population-level effects of spatial-temporal variations in exposure were elucidated in the

  4. Spatiotemporal analysis of an agent-based model of a colony of keratinocytes: a first approach for the development of validation methods

    OpenAIRE

    Pichardo-Almarza, C.; Smallwood, R.; Billings, S. A.

    2007-01-01

    Agent-based models are widely used for the simulation of systems from several domains (biology, economics, meteorology, etc). In biology agent-based models are very useful for predicting the social behaviour of systems; in particular they seem well adapted to model the behaviour of a cell population. In this paper an agent-based model, developed to study normal human keratinocytes (tissue cells), will be investigated. This kind of model exhibits probabilistic behavi...

  5. The potential of agent-based modelling for verification of people trajectories based on smartphone sensor data

    International Nuclear Information System (INIS)

    In this paper the potential of smartphone sensor data for verification of people trajectories derived from airborne remote sensing data are investigated and discussed based on simulated test recordings in the city of Osnabrueck, Germany. For this purpose, the airborne imagery is simulated by images taken from a high building with a typical single lens reflex camera. The smartphone data required for the analysis of the potential is simultaneously recorded by test persons on the ground. In a second step, the quality of the smartphone sensor data is evaluated regarding the integration into simulation and modelling approaches. In this context we studied the potential of the agent-based modelling technique concerning the verification of people trajectories

  6. An agent-based model to investigate the roles of attractive and repellent pheromones in ant decision making during foraging

    OpenAIRE

    Robinson, Elva J. H.; Ratnieks, Francis L. W.; Holcombe, M.

    2008-01-01

    Pharaoh's ants organise their foraging system using three types of trail pheromone. All previous foraging models based on specific ant foraging systems have assumed that only a single attractive pheromone is used. Here we present an agent-based model based on trail choice at a trail bifurcation within the foraging trail network of a Pharaoh's ant colony which includes both attractive (positive) and repellent (negative) trail pheromones. Experiments have previously shown that Pharaoh's ants us...

  7. Simulation of avascular tumor growth by agent-based game model involving phenotype-phenotype interactions.

    Science.gov (United States)

    Chen, Yong; Wang, Hengtong; Zhang, Jiangang; Chen, Ke; Li, Yumin

    2015-01-01

    All tumors, both benign and metastatic, undergo an avascular growth stage with nutrients supplied by the surrounding tissue. This avascular growth process is much easier to carry out in more qualitative and quantitative experiments starting from tumor spheroids in vitro with reliable reproducibility. Essentially, this tumor progression would be described as a sequence of phenotypes. Using agent-based simulation in a two-dimensional spatial lattice, we constructed a composite growth model in which the phenotypic behavior of tumor cells depends on not only the local nutrient concentration and cell count but also the game among cells. Our simulation results demonstrated that in silico tumors are qualitatively similar to those observed in tumor spheroid experiments. We also found that the payoffs in the game between two living cell phenotypes can influence the growth velocity and surface roughness of tumors at the same time. Finally, this current model is flexible and can be easily extended to discuss other situations, such as environmental heterogeneity and mutation. PMID:26648395

  8. Emergent patterns of social organization in captive Cercocebus torquatus: Testing the GrooFiWorld agent-based model

    Indian Academy of Sciences (India)

    R Dolado; F S Beltran

    2012-09-01

    We empirically applied the GrooFiWorld agent-based model (Puga-González et al. 2009) in a group of captive red-capped mangabeys (Cercocebus torquatus). We analysed several measurements related to aggression and affiliative patterns. The group adopted a combination of despotic and egalitarian behaviours resulting from the behavioural flexibility observed in the Cercopithecinae subfamily. Our study also demonstrates that the GrooFiWorld agent-based model can be extended to other members of the Cercopithecinae subfamily generating parsimonious hypotheses related to the social organization.

  9. An agent-based model of dialect evolution in killer whales.

    Science.gov (United States)

    Filatova, Olga A; Miller, Patrick J O

    2015-05-21

    The killer whale is one of the few animal species with vocal dialects that arise from socially learned group-specific call repertoires. We describe a new agent-based model of killer whale populations and test a set of vocal-learning rules to assess which mechanisms may lead to the formation of dialect groupings observed in the wild. We tested a null model with genetic transmission and no learning, and ten models with learning rules that differ by template source (mother or matriline), variation type (random errors or innovations) and type of call change (no divergence from kin vs. divergence from kin). The null model without vocal learning did not produce the pattern of group-specific call repertoires we observe in nature. Learning from either mother alone or the entire matriline with calls changing by random errors produced a graded distribution of the call phenotype, without the discrete call types observed in nature. Introducing occasional innovation or random error proportional to matriline variance yielded more or less discrete and stable call types. A tendency to diverge from the calls of related matrilines provided fast divergence of loose call clusters. A pattern resembling the dialect diversity observed in the wild arose only when rules were applied in combinations and similar outputs could arise from different learning rules and their combinations. Our results emphasize the lack of information on quantitative features of wild killer whale dialects and reveal a set of testable questions that can draw insights into the cultural evolution of killer whale dialects. PMID:25817037

  10. A three-state kinetic agent-based model to analyze tax evasion dynamics

    Science.gov (United States)

    Crokidakis, Nuno

    2014-11-01

    In this work we study the problem of tax evasion on a fully-connected population. For this purpose, we consider that the agents may be in three different states, namely honest tax payers, tax evaders and undecided, that are individuals in an intermediate class among honests and evaders. Every individual can change his/her state following a kinetic exchange opinion dynamics, where the agents interact by pairs with competitive negative (with probability q) and positive (with probability 1-q) couplings, representing agreement/disagreement between pairs of agents. In addition, we consider the punishment rules of the Zaklan econophysics model, for which there is a probability pa of an audit each agent is subject to in every period and a length of time k detected tax evaders remain honest. Our results suggest that below the critical point qc=1/4 of the opinion dynamics the compliance is high, and the punishment rules have a small effect in the population. On the other hand, for q>qc the tax evasion can be considerably reduced by the enforcement mechanism. We also discuss the impact of the presence of the undecided agents in the evolution of the system.

  11. Dynamical systems approach to the study of a sociophysics agent-based model

    International Nuclear Information System (INIS)

    The Sznajd model is a Potts-like model that has been studied in the context of sociophysics [1,2](where spins are interpreted as opinions). In a recent work [3], we generalized the Sznajd model to include assymetric interactions between the spins (interpreted as biases towards opinions) and used dynamical systems techniques to tackle its mean-field version, given by the flow: ησ = Σσ'M = 1ησησ'(ησρσ'→σ-σ'ρσ→σ').Where hs is the proportion of agents with opinion (spin)σ', M is the number of opinions and σ'→σ' is the probability weight for an agent with opinion σ being convinced by another agent with opinion σ'. We made Monte Carlo simulations of the model in a complex network (using Barabasi-Albert networks [4]) and they displayed the same attractors than the mean-field. Using linear stability analysis, we were able to determine the mean-field attractor structure analytically and to show that it has connections with well known graph theory problems (maximal independent sets and positive fluxes in directed graphs). Our dynamical systems approach is quite simple and can be used also in other models, like the voter model.

  12. The role of chromosome missegregation in cancer development: a theoretical approach using agent-based modelling.

    Directory of Open Access Journals (Sweden)

    Arturo Araujo

    Full Text Available Many cancers are aneuploid. However, the precise role that chromosomal instability plays in the development of cancer and in the response of tumours to treatment is still hotly debated. Here, to explore this question from a theoretical standpoint we have developed an agent-based model of tissue homeostasis in which to test the likely effects of whole chromosome mis-segregation during cancer development. In stochastic simulations, chromosome mis-segregation events at cell division lead to the generation of a diverse population of aneuploid clones that over time exhibit hyperplastic growth. Significantly, the course of cancer evolution depends on genetic linkage, as the structure of chromosomes lost or gained through mis-segregation events and the level of genetic instability function in tandem to determine the trajectory of cancer evolution. As a result, simulated cancers differ in their level of genetic stability and in their growth rates. We used this system to investigate the consequences of these differences in tumour heterogeneity for anti-cancer therapies based on surgery and anti-mitotic drugs that selectively target proliferating cells. As expected, simulated treatments induce a transient delay in tumour growth, and reveal a significant difference in the efficacy of different therapy regimes in treating genetically stable and unstable tumours. These data support clinical observations in which a poor prognosis is correlated with a high level of chromosome mis-segregation. However, stochastic simulations run in parallel also exhibit a wide range of behaviours, and the response of individual simulations (equivalent to single tumours to anti-cancer therapy prove extremely variable. The model therefore highlights the difficulties of predicting the outcome of a given anti-cancer treatment, even in cases in which it is possible to determine the genotype of the entire set of cells within the developing tumour.

  13. A hybrid agent-based model of the developing mammary terminal end bud.

    Science.gov (United States)

    Butner, Joseph D; Chuang, Yao-Li; Simbawa, Eman; Al-Fhaid, A S; Mahmoud, S R; Cristini, Vittorio; Wang, Zhihui

    2016-10-21

    Mammary gland ductal elongation is spearheaded by terminal end buds (TEBs), where populations of highly proliferative cells are maintained throughout post-pubertal organogenesis in virgin mice until the mammary fat pad is filled by a mature ductal tree. We have developed a hybrid multiscale agent-based model to study how cellular differentiation pathways, cellular proliferation capacity, and endocrine and paracrine signaling play a role during development of the mammary gland. A simplified cellular phenotypic hierarchy that includes stem, progenitor, and fully differentiated cells within the TEB was implemented. Model analysis finds that mammary gland development was highly sensitive to proliferation events within the TEB, with progenitors likely undergoing 2-3 proliferation cycles before transitioning to a non-proliferative phenotype, and this result is in agreement with our previous experimental work. Endocrine and paracrine signaling were found to provide reliable ductal elongation rate regulation, while variations in the probability a new daughter cell will be of a proliferative phenotype were seen to have minimal effects on ductal elongation rates. Moreover, the distribution of cellular phenotypes within the TEB was highly heterogeneous, demonstrating significant allowable plasticity in possible phenotypic distributions while maintaining biologically relevant growth behavior. Finally, simulation results indicate ductal elongation rates due to cellular proliferation within the TEB may have a greater sensitivity to upstream endocrine signaling than endothelial to stromal paracrine signaling within the TEB. This model provides a useful tool to gain quantitative insights into cellular population dynamics and the effects of endocrine and paracrine signaling within the pubertal terminal end bud. PMID:27475843

  14. Performance Evaluation of an Intelligent Agents Based Model within Irregular WSN Topologies

    Science.gov (United States)

    Ospina, Alberto Piedrahita; Cañola, Alcides Montoya; Carranza, Demetrio Ovalle

    There are many approaches proposed by the scientific community for the implementation and development of Wireless Sensor Networks (WSN). These approaches correspond to different areas of science, such as Electronics, Communications, Computing, Ubiquity, and Quality of Service among others. However, all are subject to the same constraints, because of the nature of WSN devices. The most common constraints of a WSN are the energy consumption, the network nodes organization, the sensor network's task reprogramming, the reliability in the data transmission, the resource optimization (memory and processing), etc. In the Artificial Intelligence Area is has proposed an Distributed System Approach with Mobile Intelligent Agents. An Integration Model of Mobile Intelligent Agents within Wireless Sensor Network solves some of the constraints presented above on WSŃs topologies. However, the model only was tested on the square topologies. In this way, the aim of this paper is to evaluate the performance of this model in irregular topologies.

  15. MODELING OF INVESTMENT STRATEGIES IN STOCKS MARKETS: AN APPROACH FROM MULTI AGENT BASED SIMULATION AND FUZZY LOGIC

    Directory of Open Access Journals (Sweden)

    ALEJANDRO ESCOBAR

    2010-01-01

    Full Text Available This paper presents a simulation model of a complex system, in this case a financial market, using a MultiAgent Based Simulation approach. Such model takes into account microlevel aspects like the Continuous Double Auction mechanism, which is widely used within stock markets, as well as investor agents reasoning who participate looking for profits. To model such reasoning several variables were considered including general stocks information like profitability and volatility, but also some agent's aspects like their risk tendency. All these variables are incorporated throughout a fuzzy logic approach trying to represent in a faithful manner the kind of reasoning that nonexpert investors have, including a stochastic component in order to model human factors.

  16. Jogo da Minoria: um modelo baseado em agentes aplicado ao mercado financeiro Minority Game: an agent-based model applied to financial market

    Directory of Open Access Journals (Sweden)

    Antonio Fernando Crepaldi

    2012-12-01

    Full Text Available Nos últimos anos houve uma contribuição significativa dos físicos para a construção de um tipo de modelo baseado em agentes que busca reproduzir, em simulação computacional, o comportamento do mercado financeiro. Esse modelo, chamado Jogo da Minoria consiste de um grupo de agentes que vão ao mercado comprar ou vender ativos. Eles tomam decisões com base em estratégias e, por meio delas, os agentes estabelecem um intrincado jogo de competição e coordenação pela distribuição da riqueza. O modelo tem demonstrado resultados bastante ricos e surpreendentes, tanto na dinâmica do sistema como na capacidade de reproduzir características estatísticas e comportamentais do mercado financeiro. Neste artigo, são apresentadas a estrutura e a dinâmica do Jogo da Minoria, bem como as contribuições recentes relacionadas ao Jogo da Minoria denominado de Grande Canônico, que é um modelo mais bem ajustado às características do mercado financeiro e reproduz as regularidades estatísticas do preço dos ativos chamadas fatos estilizados.Over the past ten years physicists have made a significant contribution to the building of an agent-based model to reproduce the behavior of financial markets using computer simulation. This model, called the Minority Game, consists of a group of agents that buy or sell assets. They make decisions based on strategies, and through them the agents establish an intricate game of competition and coordination resulting in the distribution of wealth. The model has shown outstanding surprising results concerning both the dynamics of the system and the ability to reproduce statistical and behavior characteristics of the financial market. In this study, the structure and dynamics of the Minority Game and the recent contributions related to the Grand Canonical Minority game, a model which is better adapted to the characteristics of the financial market and reproduce the statistical regularities of asset prices (called

  17. Evaluating Infection Prevention Strategies in Out-Patient Dialysis Units Using Agent-Based Modeling

    Science.gov (United States)

    Wares, Joanna R.; Lawson, Barry; Shemin, Douglas; D’Agata, Erika M. C.

    2016-01-01

    Patients receiving chronic hemodialysis (CHD) are among the most vulnerable to infections caused by multidrug-resistant organisms (MDRO), which are associated with high rates of morbidity and mortality. Current guidelines to reduce transmission of MDRO in the out-patient dialysis unit are targeted at patients considered to be high-risk for transmitting these organisms: those with infected skin wounds not contained by a dressing, or those with fecal incontinence or uncontrolled diarrhea. Here, we hypothesize that targeting patients receiving antimicrobial treatment would more effectively reduce transmission and acquisition of MDRO. We also hypothesize that environmental contamination plays a role in the dissemination of MDRO in the dialysis unit. To address our hypotheses, we built an agent-based model to simulate different treatment strategies in a dialysis unit. Our results suggest that reducing antimicrobial treatment, either by reducing the number of patients receiving treatment or by reducing the duration of the treatment, markedly reduces overall colonization rates and also the levels of environmental contamination in the dialysis unit. Our results also suggest that improving the environmental decontamination efficacy between patient dialysis treatments is an effective method for reducing colonization and contamination rates. These findings have important implications for the development and implementation of future infection prevention strategies. PMID:27195984

  18. Agent Based Modeling of Atherosclerosis: A Concrete Help in Personalized Treatments

    Science.gov (United States)

    Pappalardo, Francesco; Cincotti, Alessandro; Motta, Alfredo; Pennisi, Marzio

    Atherosclerosis, a pathology affecting arterial blood vessels, is one of most common diseases of the developed countries. We present studies on the increased atherosclerosis risk using an agent based model of atherogenesis that has been previously validated using clinical data. It is well known that the major risk in atherosclerosis is the persistent high level of low density lipoprotein (LDL) concentration. However, it is not known if short period of high LDL concentration can cause irreversible damage and if reduction of the LDL concentration (either by life style or drug) can drastically or partially reduce the already acquired risk. We simulated four different clinical situations in a large set of virtual patients (200 per clinical scenario). In the first one the patients lifestyle maintains the concentration of LDL in a no risk range. This is the control case simulation. The second case is represented by patients having high level of LDL with a delay to apply appropriate treatments; The third scenario is characterized by patients with high LDL levels treated with specific drugs like statins. Finally we simulated patients that are characterized by several oxidative events (smoke, sedentary life style, assumption of alcoholic drinks and so on so forth) that effective increase the risk of LDL oxidation. Those preliminary results obviously need to be clinically investigated. It is clear, however, that SimAthero has the power to concretely help medical doctors and clinicians in choosing personalized treatments for the prevention of the atherosclerosis damages.

  19. Linking Bayesian and agent-based models to simulate complex social-ecological systems in semi-arid regions

    Directory of Open Access Journals (Sweden)

    Aloah J Pope

    2015-08-01

    Full Text Available Interdependencies of ecologic, hydrologic, and social systems challenge traditional approaches to natural resource management in semi-arid regions. As a complex social-ecological system, water demands in the Sonoran Desert from agricultural and urban users often conflicts with water needs for its ecologically-significant riparian corridors. To explore this system, we developed an agent-based model to simulate complex feedbacks between human decisions and environmental conditions in the Rio Sonora Watershed. Cognitive mapping in conjunction with stakeholder participation produced a Bayesian model of conditional probabilities of local human decision-making processes resulting to changes in water demand. Probabilities created in the Bayesian model were incorporated into the agent-based model, so that each agent had a unique probability to make a positive decision based on its perceived environment at each point in time and space. By using a Bayesian approach, uncertainty in the human decision-making process could be incorporated. The spatially-explicit agent-based model simulated changes in depth-to-groundwater by well pumping based on an agent’s water demand. Changes in depth-to-groundwater feedback to influence agent behavior, as well as determine unique vegetation classes within the riparian corridor. Each vegetation class then provides varying stakeholder-defined quality values of ecosystem services. Using this modeling approach allowed us to examine effects on both the ecological and social system of semi-arid riparian corridors under various scenarios. The insight provided by the model contributes to understanding how specific interventions may alter the complex social-ecological system in the future.

  20. Collaborative Multi-Agent Based Simulations: Stakeholder-Focused Innovation in Water Resources Management and Decision-Support Modeling

    Science.gov (United States)

    Kock, B. E.

    2006-12-01

    The combined use of multi-agent based simulations and collaborative modeling approaches is emerging as a highly effective tool for representing complex coupled social-biophysical water resource systems. A collaboratively-designed, multi-agent based simulation can be used both as a decision-support tool and as a didactic method for improving stakeholder understanding and engagement with water resources policymaking and management. Major technical and non-technical obstacles remain to the efficient and effective development of multi-agent models of human society, to integrating these models with GIS and other numerical models, and to building a process for engaging stakeholders with model design, implementation and use. It is proposed here to tackle some of these obstacles through a collaborative multi-agent based simulation process framework, intended for practical use in resolving disputes and environmental challenges over sustainable irrigated agriculture in the Western United States. A practical implementation of this framework will be conducted in collaboration with a diverse stakeholder group representing farmers and local, state and federal water managers. Through the use of simulation gaming, interviewing and computer-based knowledge elicitation, a multi-agent model representing local and regional social dynamics will be developed to support the acceptable and sustainable implementation of management alternatives for reducing regional problems of salinization and high selenium concentrations in soils and irrigation water. The development of a socially and scientifically credible simulation platform in this setting can make a significant contribution to ensuring the non-adversarial use of high quality science, enhance the engagement of stakeholders with policymaking, and help meet the challenges of integrating dynamic models of human society with more traditional biophysical systems models.

  1. How appropriate are myopic optimization models to predict decision behaviour: A comparison between agent-based models and business management games

    OpenAIRE

    Appel, Franziska; Musshoff, Oliver

    2011-01-01

    Agent-based models (ABM) are used in many cases of policy assessment in agriculture. But the behavioural assumptions of these models consider farmers as myopic optimizing profit maximizers. In this contribution we compare the behaviour of myopic computer agents with the behaviour of students playing a multi period business management game. We aim to answer the question, how far are agent-based models valid to map “real” human behaviour, so that ABM can be used well for policy impact assessmen...

  2. Simulating Land-Use Change using an Agent-Based Land Transaction Model

    Science.gov (United States)

    Bakker, M. M.; van Dijk, J.; Alam, S. J.

    2013-12-01

    In the densely populated cultural landscapes of Europe, the vast majority of all land is owned by private parties, be it farmers (the majority), nature organizations, property developers, or citizens. Therewith, the vast majority of all land-use change arises from land transactions between different owner types: successful farms expand at the expense of less successful farms, and meanwhile property developers, individual citizens, and nature organizations also actively purchase land. These land transactions are driven by specific properties of the land, by governmental policies, and by the (economic) motives of both buyers and sellers. Climate/global change can affect these drivers at various scales: at the local scale changes in hydrology can make certain land less or more desirable; at the global scale the agricultural markets will affect motives of farmers to buy or sell land; while at intermediate (e.g. provincial) scales property developers and nature conservationists may be encouraged or discouraged to purchase land. The cumulative result of all these transactions becomes manifest in changing land-use patterns, and consequent environmental responses. Within the project Climate Adaptation for Rural Areas an agent-based land-use model was developed that explores the future response of individual land users to climate change, within the context of wider global change (i.e. policy and market change). It simulates the exchange of land among farmers and between farmers and nature organizations and property developers, for a specific case study area in the east of the Netherlands. Results show that local impacts of climate change can result in a relative stagnation in the land market in waterlogged areas. Furthermore, the increase in dairying at the expense of arable cultivation - as has been observed in the area in the past - is slowing down as arable produce shows a favourable trend in the agricultural world market. Furthermore, budgets for nature managers are

  3. Toward an Agent-Based Model of Socially Optimal Water Rights Markets

    Science.gov (United States)

    Ehlen, M. A.

    2004-12-01

    There has been considerable interest lately in using public markets for buying and selling the rights to local water usage. Such water rights markets, if designed correctly, should be socially optimal, that is, should sell rights at prices that reflect the true value of water in the region, taking into account that water rights buyers and sellers represent a disparate group of private industry, public authorities, and private users, each having different water needs and different priority to local government. Good market design, however, is hard. As was experienced in California short-run electric power markets, a market design that on paper looks reasonable but in practice is mal-constructed can have devastating effects: firms can learn to manipulate prices by `playing' both sides of the market, and sellers can under-provide so as to create exorbitant prices which buyers have no choice but to pay. Economic theory provides several frameworks for developing a good water rights market design; for example, the structure-conduct-performance paradigm (SCPP) suggests that, among other things, the number and types of buyers and sellers (structure), and transaction clearing rules and government policies (conduct) affect in very particular ways the prices and quantities (performance) in the market. In slow-moving or static markets, SCPP has been a useful predictor of market performance; in faster markets the market dynamics that endogenously develop over time are often too complex to predict with SCPP or other existing modeling techniques. New, more sophisticated combinations of modeling and simulation are needed. Toward developing a good (i.e., socially optimal) water rights market design that can take into account the dynamics inherent in the water sector, we are developing an agent-based model of water rights markets. The model serves two purposes: first, it provides an SCPP-based framework of water rights markets that takes into account the particular structure of

  4. Development of a physiologically-based computational kidney model to describe the renal excretion of hydrophilic agents in rats

    OpenAIRE

    ChristophNiederalt; PhilippLengsfeld; KarinaClaaßen; RolfBurghaus; MatthiasBräutigam; HubertusPietsch

    2013-01-01

    A physiologically-based kidney model was developed to analyze the renal excretion and kidney exposure of hydrophilic agents, in particular contrast media, in rats. In order to study the influence of osmolality and viscosity changes, the model mechanistically represents urine concentration by water re-absorption in different segments of kidney tubules and viscosity dependent tubular fluid flow. The model was established using experimental data on the physiological steady state without admin...

  5. Development of a Physiologically Based Computational Kidney Model to Describe the Renal Excretion of Hydrophilic Agents in Rats

    OpenAIRE

    Niederalt, Christoph; Wendl, Thomas; Kuepfer, Lars; Claassen, Karina; Loosen, Roland; Willmann, Stefan; Lippert, Joerg; Schultze-Mosgau, Marcus; Winkler, Julia; Burghaus, Rolf; Bräutigam, Matthias; Pietsch, Hubertus; Lengsfeld, Philipp

    2013-01-01

    A physiologically based kidney model was developed to analyze the renal excretion and kidney exposure of hydrophilic agents, in particular contrast media, in rats. In order to study the influence of osmolality and viscosity changes, the model mechanistically represents urine concentration by water reabsorption in different segments of kidney tubules and viscosity dependent tubular fluid flow. The model was established using experimental data on the physiological steady state without administr...

  6. The critical properties of the agent-based model with environmental-economic interactions

    Science.gov (United States)

    Kuscsik, Z.; Horváth, D.

    2008-05-01

    The steady-state and nonequilibrium properties of the model of environmental-economic interactions are studied. The interacting heterogeneous agents are simulated on the platform of the emission dynamics of cellular automaton. The diffusive emissions are produced by the factory agents, and the local pollution is monitored by the randomly walking (mobile) sensors. When the threshold concentration is exceeded, a feedback signal is transmitted from the sensor to the nearest factory that affects its actual production rate. The model predicts the discontinuous phase transition between safe and catastrophic ecology. Right at the critical line, the broad-scale power-law distributions of emission rates have been identified. The power-law fluctuations are triggered by the screening effect of factories and by the time delay between the environment contamination and its detection. The system shows the typical signs of the self-organized critical systems, such as power-law distributions and scaling laws.

  7. Diffusion of a Sustainable Farming Technique in Sri Lanka: An Agent-Based Modeling Approach

    Science.gov (United States)

    Jacobi, J. H.; Gilligan, J. M.; Carrico, A. R.; Truelove, H. B.; Hornberger, G.

    2012-12-01

    We live in a changing world - anthropogenic climate change is disrupting historic climate patterns and social structures are shifting as large scale population growth and massive migrations place unprecedented strain on natural and social resources. Agriculture in many countries is affected by these changes in the social and natural environments. In Sri Lanka, rice farmers in the Mahaweli River watershed have seen increases in temperature and decreases in precipitation. In addition, a government led resettlement project has altered the demographics and social practices in villages throughout the watershed. These changes have the potential to impact rice yields in a country where self-sufficiency in rice production is a point of national pride. Studies of the climate can elucidate physical effects on rice production, while research on social behaviors can illuminate the influence of community dynamics on agricultural practices. Only an integrated approach, however, can capture the combined and interactive impacts of these global changes on Sri Lankan agricultural. As part of an interdisciplinary team, we present an agent-based modeling (ABM) approach to studying the effects of physical and social changes on farmers in Sri Lanka. In our research, the diffusion of a sustainable farming technique, the system of rice intensification (SRI), throughout a farming community is modeled to identify factors that either inhibit or promote the spread of a more sustainable approach to rice farming. Inputs into the ABM are both physical and social and include temperature, precipitation, the Palmer Drought Severity Index (PDSI), community trust, and social networks. Outputs from the ABM demonstrate the importance of meteorology and social structure on the diffusion of SRI throughout a farming community.

  8. Proceedings First Workshop on Applications of Membrane computing, Concurrency and Agent-based modelling in POPulation biology

    CERN Document Server

    Milazzo, Paolo; 10.4204/EPTCS.33

    2010-01-01

    This volume contains the papers presented at the first International Workshop on Applications of Membrane Computing, Concurrency and Agent-based Modelling in Population Biology (AMCA-POP 2010) held in Jena, Germany on August 25th, 2010 as a satellite event of the 11th Conference on Membrane Computing (CMC11). The aim of the workshop is to investigate whether formal modelling and analysis techniques could be applied with profit to systems of interest for population biology and ecology. The considered modelling notations include membrane systems, Petri nets, agent-based notations, process calculi, automata-based notations, rewriting systems and cellular automata. Such notations enable the application of analysis techniques such as simulation, model checking, abstract interpretation and type systems to study systems of interest in disciplines such as population biology, ecosystem science, epidemiology, genetics, sustainability science, evolution and other disciplines in which population dynamics and interactions...

  9. Effects of diversification among assets in an agent-based market model

    CERN Document Server

    Ghoulmié, F; Mellen, C P; Di Matteo, T

    2007-01-01

    We extend to the multi-asset case the framework of a discrete time model of a single asset financial market developed in Ghoulmie et al (2005). In particular, we focus on adaptive agents with threshold behavior allocating their resources among two assets. We explore numerically the effect of this diversification as an additional source of complexity in the financial market and we discuss its destabilizing role. We also point out the relevance of these studies for financial decision making.

  10. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    This thesis investigates the possibilities in applying Operations Research (OR) to autonomous vehicular traffic. The explicit difference to most other research today is that we presume that an agent is present in every vehicle - hence Agent Based Individual Traffic guidance (ABIT). The next...... that the system can be divided into two separate constituents. The immediate dispersion, which is used for small areas and quick response, and the individual alleviation, which considers the longer distance decision support. Both of these require intrinsicate models and cost functions which at the...... beginning of the project were not previously considered. We define a special inseparable cost function and develop a solution complex capable of using this cost function. In relation to calibration and estimation of statistical models used for dynamic route guidance we worked with generating random number...

  11. Approach and development strategy for an agent-based model of economic confidence.

    Energy Technology Data Exchange (ETDEWEB)

    Sprigg, James A.; Pryor, Richard J.; Jorgensen, Craig Reed

    2004-08-01

    We are extending the existing features of Aspen, a powerful economic modeling tool, and introducing new features to simulate the role of confidence in economic activity. The new model is built from a collection of autonomous agents that represent households, firms, and other relevant entities like financial exchanges and governmental authorities. We simultaneously model several interrelated markets, including those for labor, products, stocks, and bonds. We also model economic tradeoffs, such as decisions of households and firms regarding spending, savings, and investment. In this paper, we review some of the basic principles and model components and describe our approach and development strategy for emulating consumer, investor, and business confidence. The model of confidence is explored within the context of economic disruptions, such as those resulting from disasters or terrorist events.

  12. Agent-Based Modeling and Simulation of Network Infrastructure Cyber-Attacks and Cooperative Defense Mechanisms

    OpenAIRE

    Kotenko, Igor

    2010-01-01

    This paper considered the approach to investigation of distributed cooperative cyberdefence mechanisms against network attacks. The approach is based on the simulation of network cyber-attacks (Distributed Denial of Service, network worms, botnets, etc.) and cyber-protection mechanisms which combines discrete-event simulation, multi-agent approach and packet-level simulation of network protocols. The environment developed is written in C++ and OMNeT++. It allows imitating a wide spectrum of r...

  13. Modeling and implementing an agent-based environmental health impact decision support system

    OpenAIRE

    Sokolova, Marina; Fernández Caballero, Antonio

    2009-01-01

    This paper presents an approach to the creation of an agent-based system for the assessment of environmental impact upon human health. As indicators of the environmental impact water pollution, indexes of traffic and industrial activity, wastes and solar radiation are assumed. And as human health indicator morbidity is taken. All the data comprise multiple heterogeneous data repositories. The system is logically and functionally divided into three layers, solving the tasks of information fusi...

  14. A market-oriented agent-based model for information retrieval

    OpenAIRE

    Menacer, Djamel Eddine; Sibertin-Blanc, Christophe; Drias, Habiba

    2013-01-01

    International audience Information Retrieval in the World Wide Web (Web IR) is essential for a number of activities and it is an active domain of research and development. The main challenges concern the relevance of the results provided to users' queries and the performance regarding respond-time. On the other hand, agent-based market systems prove to be efficient for implementing e-commerce or B2B applications on the internet, thanks to inherent properties such as prominency of interacti...

  15. Application of statistical emulation to an agent-based model: assortative mating and the reversal of gender inequality in education in Belgium.

    OpenAIRE

    De Mulder, Wim; Grow, André; Molenberghs, Geert; Verbeke, Geert

    2015-01-01

    We describe the application of statistical emulation to the outcomes of an agent-based model. The agent-based model simulates the mechanisms that might have linked the reversal of gender inequality in higher education with observed changes in educational assortative mating in Belgium. Using the statistical emulator as a computationally fast approximation to the expensive agent-based model, it is feasible to use a genetic algorithm in nding the parameter values for which the correspondin...

  16. Modeling interdependent socio-technical networks: The smart grid—an agent-based modeling approach

    NARCIS (Netherlands)

    Worm, D.; Langley, D.J.; Becker, J.

    2014-01-01

    The aim of this paper is to improve scientific modeling of interdependent socio-technical networks. In these networks the interplay between technical or infrastructural elements on the one hand and social and behavioral aspects on the other hand, plays an important role. Examples include electricity

  17. Modelling Multi-agent in Emission Market based on Experimental Economics Simulations

    DEFF Research Database (Denmark)

    Chao, Jiang; Xue, Yusheng; Jie, Huang; Wu, Qiuwei; Yang, Guangya

    2014-01-01

    influencing rules on human partic ipants’ uncertain behaviors are extracted, which can aid the construction of multi-agent stochastic models with the same distribution characteristics. In this way, only a small group of humans are needed to represent the special decision makers, who can inte ract with large...... numbers of multi-agents constructed by the aforementioned method. The methodology discussed in this paper can overcome the scale limitations and meanwhile maintain the merits of experimental economics....... the multi-scenario experiments is also limited due to the variations of human participants ’ concentration level. This paper adopts a hybrid interactive simulation methodology. Human-subjected experime nts with a small group of human participants are conducted, major driving factors and their...

  18. Designing across ages: Multi-agent-based models and learning electricity

    Science.gov (United States)

    Sengupta, Pratim

    Electricity is regarded as one of the most challenging topics for students at all levels -- middle school -- college (Cohen, Eylon, & Ganiel, 1983; Belcher & Olbert, 2003; Eylon & Ganiel, 1990; Steinberg et al., 1985). Several researchers have suggested that naive misconceptions about electricity stem from a deep incommensurability (Slotta & Chi, 2006; Chi, 2005) or incompatibility (Chi, Slotta & Leauw, 1994; Reiner, Slotta, Chi, & Resnick, 2000) between naive and expert knowledge structures. I first present an alternative theoretical framework that adopts an emergent levels-based perspective as proposed by Wilensky & Resnick (1999). From this perspective, macro-level phenomena such as electric current and resistance, as well as behavior of linear electric circuits, can be conceived of as emergent from simple, body-syntonic interactions between electrons and ions in a circuit. I argue that adopting such a perspective enables us to reconceive commonly noted misconceptions in electricity as behavioral evidences of "slippage between levels" -- i.e., these misconceptions appear when otherwise productive knowledge elements are sometimes inappropriately activated due to certain macro-level phenomenological cues only -- and, that the same knowledge elements when activated due to phenomenological cues at both micro- and macro-levels, can engender a deeper, expert-like understanding. I will then introduce NIELS (NetLogo Investigations In Electromagnetism, Sengupta & Wilensky, 2006, 2008, 2009), a low-threshold high-ceiling (LTHC) learning environment of multi-agent-based computational models that represent phenomena such as electric current and resistance, as well as the behavior of linear electric circuits, as emergent. I also present results from implementations of NIELS in 5th, 7th and 12th grade classrooms that show the following: (a) how leveraging certain "design elements" over others in NIELS models can create new phenomenological cues, which in turn can be

  19. Comparison of Communication Models for Mobile Agents

    Directory of Open Access Journals (Sweden)

    Xining Li

    2003-04-01

    Full Text Available An agent is a self-contained process being acting on behalf of a user. A Mobile Agent is an agent roaming the internet to access data and services, and carry out its assigned task remotely. This paper will focus on the communication models for Mobile Agents. Generally speaking, communication models concern with problems of how to name Mobile Agents, how to establish communication relationships, how to trace moving agents, and how to guarantee reliable communication. Some existing MA systems are purely based on RPC-style communication, whereas some adopts asynchronous message passing, or event registration/handling. Different communication concepts suitable for Mobile Agents are well discussed in [1]. However, we will investigate these concepts and existing models from a different point view: how to track down agents and deliver messages in a dynamic, changing world.

  20. Multi-agents Based Modelling for Distribution Network Operation with Electric Vehicle Integration

    DEFF Research Database (Denmark)

    Hu, Junjie; Morais, Hugo; Zong, Yi;

    2014-01-01

    and they represent EV owners and operate the charging behaviour of EVs. To simulate this collaborative (all agents contribute to achieving an optimized global performance) but also competitive environment (each agent will try to increase its utilities or reduce its costs), a multi-agent platform was developed......Electric vehicles (EV) can become integral part of a smart grid because instead of just consuming power they are capable of providing valuable services to power systems. To integrate EVs smoothly into the power systems, a multi-agents system (MAS) with hierarchical organization structure...... is proposed in this paper. The proposed MAS system consists of three types of agents: distribution system operator agent (DSO agent), electric vehicle fleet operator agent (EV FO agent or alternatively called virtual power plant agent) and EV agent. A DSO agent belongs to the top level of the hierarchy...

  1. Alternative Supply Chain Production-Sales Policies for New Product Diffusion: An Agent-Based Modeling and Simulation Approach

    OpenAIRE

    Amini, Mehdi; Wakolbinger, Tina; Racer, Michael; Nejad, Mohammed G.

    2012-01-01

    Applying Agent-Based Modeling and Simulation (ABMS) methodology, this paper analyzes the impact of alternative production-sales policies on the diffusion of a new product and the generated NPV of profit. The key features of the ABMS model, that captures the marketplace as a complex adaptive system, are: (i) supply chain capacity is constrained; (ii) consumers' new product adoption decisions are influenced by marketing activities as well as positive and negative word of mouth (W...

  2. Memory Transmission in Small Groups and Large Networks: An Agent-Based Model.

    Science.gov (United States)

    Luhmann, Christian C; Rajaram, Suparna

    2015-12-01

    The spread of social influence in large social networks has long been an interest of social scientists. In the domain of memory, collaborative memory experiments have illuminated cognitive mechanisms that allow information to be transmitted between interacting individuals, but these experiments have focused on small-scale social contexts. In the current study, we took a computational approach, circumventing the practical constraints of laboratory paradigms and providing novel results at scales unreachable by laboratory methodologies. Our model embodied theoretical knowledge derived from small-group experiments and replicated foundational results regarding collaborative inhibition and memory convergence in small groups. Ultimately, we investigated large-scale, realistic social networks and found that agents are influenced by the agents with which they interact, but we also found that agents are influenced by nonneighbors (i.e., the neighbors of their neighbors). The similarity between these results and the reports of behavioral transmission in large networks offers a major theoretical insight by linking behavioral transmission to the spread of information. PMID:26553014

  3. Evaluating environmental strategies in a textile printing and dyeing enterprise by an agent-based simulation model

    Science.gov (United States)

    Gao, Lei; Ding, Yongsheng; Li, Fang

    2013-05-01

    To improve the capabilities of saving energy and reducing pollutant emission of textile printing and dyeing (PD) industry, this article presents a novel agent-based simulation model for assessing the impacts of environmental strategies on a PD enterprise. Two typical PD enterprises in China are simulated with different modelling granularities: one is at a module level, while the other is at an enterprise level. The module-level simulation model depicts detailed production processes in a PD enterprise and evaluates five candidate strategies on their capabilities of improving energy usage and waste emission. The enterprise-level simulation model views a PD enterprise as an agent and assesses three tax strategies for waste discharge. The simulation results show that the proposed general model could be a valuable tool to explore potential solutions to saving energy and reducing waste emission in PD enterprises, after being calibrated to a real case.

  4. Service Oriented Architecture for Business Dynamics: An Agent Based Business Modeling Approach

    Directory of Open Access Journals (Sweden)

    O. P. Rishi

    2009-01-01

    Full Text Available In today's rapidly changing environment the industries areinterested in executing business functions that has scope inmultiple applications. Business dynamics and technologicalinnovations have felt organizations to comply with adisparate mix of operating systems, applications anddatabases. This makes it difficult, time-consuming and costlyfor IT departments to deliver new applications that integrateheterogeneous technologies. It demands high interoperabilityand more flexible and adaptive business processmanagement. The inclination is to have systems assembled,from a loosely coupled collection of Web services, which areuniversal and integrated. This technical area appears tohave scope where the Agent Technology can be exploitedwith significant advantages. With Service OrientedArchitecture a decomposable architecture, and associatedset of development and IT management disciplines,composed of loosely coupled services communicating viapre-established protocols, these services can be assembledad-hoc to form customized applications that address a widevariety of business requirements.In the present paper, we propose a conceptual frameworkfor agent-based Service Oriented Architecture (SOA. Inwhich we try to integrate Service Oriented Architecture withthe agent technology & other tactical technologies like webservices, business workflow services, Business meta-rules,search optimization of services and semantic Webtechnology for business service mappings.

  5. The role of research efficiency in the evolution of scientific productivity and impact: An agent-based model

    Science.gov (United States)

    You, Zhi-Qiang; Han, Xiao-Pu; Hadzibeganovic, Tarik

    2016-02-01

    We introduce an agent-based model to investigate the effects of production efficiency (PE) and hot field tracing capability (HFTC) on productivity and impact of scientists embedded in a competitive research environment. Agents compete to publish and become cited by occupying the nodes of a citation network calibrated by real-world citation datasets. Our Monte-Carlo simulations reveal that differences in individual performance are strongly related to PE, whereas HFTC alone cannot provide sustainable academic careers under intensely competitive conditions. Remarkably, the negative effect of high competition levels on productivity can be buffered by elevated research efficiency if simultaneously HFTC is sufficiently low.

  6. An Agent-based approach to modelling integrated product teams undertaking a design activity.

    OpenAIRE

    Sim, Yee Wai; Crowder, Richard; Robinson, Mark; Hughes, Helen

    2009-01-01

    The interactions between individual designers, within integrated product teams, and the nature of design tasks, all have a significant impact upon how well a design task can be performed, and hence the quality of the resultant product and the time in which it can be delivered. In this paper we describe an ongoing research project which aims to model integrated product teams through the use of multi-agent systems. We first describe the background and rationale for our work, and then present ou...

  7. Agent based models for testing city evacuation strategies under a flood event as strategy to reduce flood risk

    Science.gov (United States)

    Medina, Neiler; Sanchez, Arlex; Nokolic, Igor; Vojinovic, Zoran

    2016-04-01

    This research explores the uses of Agent Based Models (ABM) and its potential to test large scale evacuation strategies in coastal cities at risk from flood events due to extreme hydro-meteorological events with the final purpose of disaster risk reduction by decreasing human's exposure to the hazard. The first part of the paper corresponds to the theory used to build the models such as: Complex adaptive systems (CAS) and the principles and uses of ABM in this field. The first section outlines the pros and cons of using AMB to test city evacuation strategies at medium and large scale. The second part of the paper focuses on the central theory used to build the ABM, specifically the psychological and behavioral model as well as the framework used in this research, specifically the PECS reference model is cover in this section. The last part of this section covers the main attributes or characteristics of human beings used to described the agents. The third part of the paper shows the methodology used to build and implement the ABM model using Repast-Symphony as an open source agent-based modelling and simulation platform. The preliminary results for the first implementation in a region of the island of Sint-Maarten a Dutch Caribbean island are presented and discussed in the fourth section of paper. The results obtained so far, are promising for a further development of the model and its implementation and testing in a full scale city

  8. A MARKET-ORIENTED AGENTS-BASED MODEL FOR INFORMATION RETRIEVAL

    OpenAIRE

    Djamel Eddine Menacer; Christophe Sibertin-Blanc; Habiba Drias

    2014-01-01

    Information Retrieval in the World Wide Web (Web IR) is essential for a number of activities and it is an active domain of research and devel-opment. The main challenges concern the rele-vance of the results provided to users' queries and the performance regarding respond-time. On the other hand, agent-based market systems prove to be efficient for implementing e-commerce or B2B applications on the internet, thanks to inherent properties such as prominency of interactions, scalability, flexib...

  9. Modelling Temporal Schedule of Urban Trains Using Agent-Based Simulation and NSGA2-BASED Multiobjective Optimization Approaches

    Science.gov (United States)

    Sahelgozin, M.; Alimohammadi, A.

    2015-12-01

    Increasing distances between locations of residence and services leads to a large number of daily commutes in urban areas. Developing subway systems has been taken into consideration of transportation managers as a response to this huge amount of travel demands. In developments of subway infrastructures, representing a temporal schedule for trains is an important task; because an appropriately designed timetable decreases Total passenger travel times, Total Operation Costs and Energy Consumption of trains. Since these variables are not positively correlated, subway scheduling is considered as a multi-criteria optimization problem. Therefore, proposing a proper solution for subway scheduling has been always a controversial issue. On the other hand, research on a phenomenon requires a summarized representation of the real world that is known as Model. In this study, it is attempted to model temporal schedule of urban trains that can be applied in Multi-Criteria Subway Schedule Optimization (MCSSO) problems. At first, a conceptual framework is represented for MCSSO. Then, an agent-based simulation environment is implemented to perform Sensitivity Analysis (SA) that is used to extract the interrelations between the framework components. These interrelations is then taken into account in order to construct the proposed model. In order to evaluate performance of the model in MCSSO problems, Tehran subway line no. 1 is considered as the case study. Results of the study show that the model was able to generate an acceptable distribution of Pareto-optimal solutions which are applicable in the real situations while solving a MCSSO is the goal. Also, the accuracy of the model in representing the operation of subway systems was significant.

  10. MODELLING TEMPORAL SCHEDULE OF URBAN TRAINS USING AGENT-BASED SIMULATION AND NSGA2-BASED MULTIOBJECTIVE OPTIMIZATION APPROACHES

    Directory of Open Access Journals (Sweden)

    M. Sahelgozin

    2015-12-01

    Full Text Available Increasing distances between locations of residence and services leads to a large number of daily commutes in urban areas. Developing subway systems has been taken into consideration of transportation managers as a response to this huge amount of travel demands. In developments of subway infrastructures, representing a temporal schedule for trains is an important task; because an appropriately designed timetable decreases Total passenger travel times, Total Operation Costs and Energy Consumption of trains. Since these variables are not positively correlated, subway scheduling is considered as a multi-criteria optimization problem. Therefore, proposing a proper solution for subway scheduling has been always a controversial issue. On the other hand, research on a phenomenon requires a summarized representation of the real world that is known as Model. In this study, it is attempted to model temporal schedule of urban trains that can be applied in Multi-Criteria Subway Schedule Optimization (MCSSO problems. At first, a conceptual framework is represented for MCSSO. Then, an agent-based simulation environment is implemented to perform Sensitivity Analysis (SA that is used to extract the interrelations between the framework components. These interrelations is then taken into account in order to construct the proposed model. In order to evaluate performance of the model in MCSSO problems, Tehran subway line no. 1 is considered as the case study. Results of the study show that the model was able to generate an acceptable distribution of Pareto-optimal solutions which are applicable in the real situations while solving a MCSSO is the goal. Also, the accuracy of the model in representing the operation of subway systems was significant.

  11. A multi-agent cell-based model for wound contraction.

    Science.gov (United States)

    Boon, W M; Koppenol, D C; Vermolen, F J

    2016-05-24

    A mathematical model for wound contraction is presented. The model is based on a cell-based formalism where fibroblasts, myofibroblasts and the immune reaction are taken into account. The model is used to simulate contraction of a wound using point forces on the cell boundary and it also determines the orientation of collagen after restoration of the damage. The paper presents the mathematical model in terms of the equations and assumptions, as well as some implications of the modelling. The present model predicts that the amount of final contraction is larger if the migration velocity of the leukocytes is larger and hence it is important that the immune system functions well to prevent contractures. Further, the present model is the first cell-based model that combines the immune system to final contractions. PMID:26805459

  12. Remembering what we like: Toward an agent-based model of Web traffic

    CERN Document Server

    Goncalves, Bruno; Ramasco, Jose J; Flammini, Alessandro; Menczer, Filippo

    2009-01-01

    Analysis of aggregate Web traffic has shown that PageRank is a poor model of how people actually navigate the Web. Using the empirical traffic patterns generated by a thousand users over the course of two months, we characterize the properties of Web traffic that cannot be reproduced by Markovian models, in which destinations are independent of past decisions. In particular, we show that the diversity of sites visited by individual users is smaller and more broadly distributed than predicted by the PageRank model; that link traffic is more broadly distributed than predicted; and that the time between consecutive visits to the same site by a user is less broadly distributed than predicted. To account for these discrepancies, we introduce a more realistic navigation model in which agents maintain individual lists of bookmarks that are used as teleportation targets. The model can also account for branching, a traffic property caused by browser features such as tabs and the back button. The model reproduces aggre...

  13. Agent-based Modeling Simulation Analysis on the Regulation of Institutional Investor's Encroachment Behavior in Stock Market

    Directory of Open Access Journals (Sweden)

    Yang Li

    2014-05-01

    Full Text Available Purpose: This study explores the effective regulation of institutional investor's encroachment behavior in stock market. Given the theoretical and practical importance, the present study examines the effect of the self-adaptive regulation strategy (adjusting the regulation factors such as punishment and the probability of investigating successfully in time for the sake of the small & medium-sized investor protection.Design/methodology/approach: This study was carried out through game theory and agent-based modeling simulation. Firstly, a dynamic game model was built to search the core factors of regulation and the equilibrium paths. Secondly, an agent-based modeling simulation model was built in Swarm to extend the game model. Finally, a simulation experiment (using virtual parameter values was performed to examine the effect of regulation strategy obtained form game model.Findings: The results of this study showed that the core factors of avoiding the institutional investor's encroachment behavior are the punishment and the probability of investigating successfully of the regulator. The core factors embody as the self-adaptability and the capability of regulator. If the regulator can adjust the regulation factors in time, the illegal behaviors will be avoided effectively.Research limitations/implications: The simulation experiment in this paper was performed with virtual parameter values. Although the results of experiment showed the effect of self-adaptive regulation, there are still some differences between simulation experiment and real market situation.Originality/value: The purpose of this study is to investigate an effective regulation strategy of institutional investor's encroachment behavior in stock market in order to maintain market order and protect the benefits of investors. Base on the game model and simulation model, a simulation experiment was preformed and the result showed that the self-adaptive regulation would be effective

  14. Environmental Sustainability and Effects on Urban Micro Region using Agent-Based Modeling of Urbanisation in Select Major Indian Cities

    Science.gov (United States)

    Aithal, B. H.

    2015-12-01

    Abstract: Urbanisation has gained momentum with globalization in India. Policy decisions to set up commercial, industrial hubs have fuelled large scale migration, added with population upsurge has contributed to the fast growing urban region that needs to be monitored in order to design sustainable urban cities. Unplanned urbanization have resulted in the growth of peri-urban region referred to as urban sprawl, are often devoid of basic amenities and infrastructure leading to large scale environmental problems that are evident. Remote sensing data acquired through space borne sensors at regular interval helps in understanding urban dynamics aided by Geoinformatics which has proved very effective in mapping and monitoring for sustainable urban planning. Cellular automata (CA) is a robust approach for the spatially explicit simulation of land-use land cover dynamics. CA uses rules, states, conditions that are vital factors in modelling urbanisation. This communication effectively introduces simulation assistances of CA with the agent based modelling supported by its fuzzy characteristics and weightages through analytical hierarchal process (AHP). This has been done considering perceived agents such as industries, natural resource etc. Respective agent's role in development of a particular regions into an urban area has been examined with weights and its influence of each of these agents based on its characteristics functions. Validation was performed obtaining a high kappa coefficient indicating the quality and the allocation performance of the model & validity of the model to predict future projections. The prediction using the proposed model was performed for 2030. Further environmental sustainability of each of these cities are explored such as water features, environment, greenhouse gas emissions, effects on human human health etc., Modeling suggests trend of various land use classes transformation with the spurt in urban expansions based on specific regions and

  15. A Q-learning agent-based model for the analysis of the power market dynamics

    International Nuclear Information System (INIS)

    The introduction of deregulation in the electricity sector resulted in a different way of thinking and acting on the part of producers. Power suppliers strive to maximize their profit and their utilization rate through a bidding process. According to the pricing system, the competition conditions, the demand side bidding, and the available information, they develop different bidding strategies in order to exploit every possible advantage. This paper presents the Q-Learning algorithm in order to model the bidding strategy of suppliers in electricity auctions. The study examined players' behaviour in the spot market and the change in their policy under different conditions of demand. The Q-learning algorithm considers a novel approach to the definition of states and actions. States are not defined exclusively, as states of the environment, but rather, are different for each agent and relative to the impact the environment has on the agent. Actions are not represented by the price the agent bids, but by the variation between the previous and the new bid price. Market structure was described in this paper and the supplier's bidding problem was formulated in terms of Q-learning. A description of the test system was presented and the parameter selection of the algorithm, as well as the presentation and the results of four case study simulations were discussed. The Q-learning algorithm in supplier bidding strategy showed very promising results. it was suggested that the research should be expanded to include more producers or tests of transmission systems. 9 refs., 2 tabs., 6 figs

  16. Agent Based Individual Traffic guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen Bundgaard

    2004-01-01

    vehicle can be obtained through cellular phone tracking or GPS systems. This information can then be used to provide individual traffic guidance as opposed to the mass information systems of today -- dynamic roadsigns and trafficradio. The goal is to achieve better usage of road and time. The main topic......When working with traffic planning or guidance it is common practice to view the vehicles as a combined mass. >From this models are employed to specify the vehicle supply and demand for each region. As the models are complex and the calculations are equally demanding the regions and the detail of...... the road network is aggregated. As a result the calculations reveal only what the mass of vehicles are doing and not what a single vehicle is doing. This is the crucial difference to ABIT (Agent Based Individual Trafficguidance). ABIT is based on the fact that information on the destination of each...

  17. Agent-based models of strategies for the emergence and evolution of grammatical agreement.

    Science.gov (United States)

    Beuls, Katrien; Steels, Luc

    2013-01-01

    Grammatical agreement means that features associated with one linguistic unit (for example number or gender) become associated with another unit and then possibly overtly expressed, typically with morphological markers. It is one of the key mechanisms used in many languages to show that certain linguistic units within an utterance grammatically depend on each other. Agreement systems are puzzling because they can be highly complex in terms of what features they use and how they are expressed. Moreover, agreement systems have undergone considerable change in the historical evolution of languages. This article presents language game models with populations of agents in order to find out for what reasons and by what cultural processes and cognitive strategies agreement systems arise. It demonstrates that agreement systems are motivated by the need to minimize combinatorial search and semantic ambiguity, and it shows, for the first time, that once a population of agents adopts a strategy to invent, acquire and coordinate meaningful markers through social learning, linguistic self-organization leads to the spontaneous emergence and cultural transmission of an agreement system. The article also demonstrates how attested grammaticalization phenomena, such as phonetic reduction and conventionalized use of agreement markers, happens as a side effect of additional economizing principles, in particular minimization of articulatory effort and reduction of the marker inventory. More generally, the article illustrates a novel approach for studying how key features of human languages might emerge. PMID:23527055

  18. Agent-based models of strategies for the emergence and evolution of grammatical agreement.

    Directory of Open Access Journals (Sweden)

    Katrien Beuls

    Full Text Available Grammatical agreement means that features associated with one linguistic unit (for example number or gender become associated with another unit and then possibly overtly expressed, typically with morphological markers. It is one of the key mechanisms used in many languages to show that certain linguistic units within an utterance grammatically depend on each other. Agreement systems are puzzling because they can be highly complex in terms of what features they use and how they are expressed. Moreover, agreement systems have undergone considerable change in the historical evolution of languages. This article presents language game models with populations of agents in order to find out for what reasons and by what cultural processes and cognitive strategies agreement systems arise. It demonstrates that agreement systems are motivated by the need to minimize combinatorial search and semantic ambiguity, and it shows, for the first time, that once a population of agents adopts a strategy to invent, acquire and coordinate meaningful markers through social learning, linguistic self-organization leads to the spontaneous emergence and cultural transmission of an agreement system. The article also demonstrates how attested grammaticalization phenomena, such as phonetic reduction and conventionalized use of agreement markers, happens as a side effect of additional economizing principles, in particular minimization of articulatory effort and reduction of the marker inventory. More generally, the article illustrates a novel approach for studying how key features of human languages might emerge.

  19. Incorporating GIS data into an agent-based model to support planning policy making for the development of creative industries

    Science.gov (United States)

    Liu, Helin; Silva, Elisabete A.; Wang, Qian

    2016-07-01

    This paper presents an extension to the agent-based model "Creative Industries Development-Urban Spatial Structure Transformation" by incorporating GIS data. Three agent classes, creative firms, creative workers and urban government, are considered in the model, and the spatial environment represents a set of GIS data layers (i.e. road network, key housing areas, land use). With the goal to facilitate urban policy makers to draw up policies locally and optimise the land use assignment in order to support the development of creative industries, the improved model exhibited its capacity to assist the policy makers conducting experiments and simulating different policy scenarios to see the corresponding dynamics of the spatial distributions of creative firms and creative workers across time within a city/district. The spatiotemporal graphs and maps record the simulation results and can be used as a reference by the policy makers to adjust land use plans adaptively at different stages of the creative industries' development process.

  20. Incorporating GIS data into an agent-based model to support planning policy making for the development of creative industries

    Science.gov (United States)

    Liu, Helin; Silva, Elisabete A.; Wang, Qian

    2016-06-01

    This paper presents an extension to the agent-based model "Creative Industries Development-Urban Spatial Structure Transformation" by incorporating GIS data. Three agent classes, creative firms, creative workers and urban government, are considered in the model, and the spatial environment represents a set of GIS data layers (i.e. road network, key housing areas, land use). With the goal to facilitate urban policy makers to draw up policies locally and optimise the land use assignment in order to support the development of creative industries, the improved model exhibited its capacity to assist the policy makers conducting experiments and simulating different policy scenarios to see the corresponding dynamics of the spatial distributions of creative firms and creative workers across time within a city/district. The spatiotemporal graphs and maps record the simulation results and can be used as a reference by the policy makers to adjust land use plans adaptively at different stages of the creative industries' development process.

  1. Market stability vs. market resilience : regulatory policies experiments in an agent-based model with low - and high- frequency trading

    OpenAIRE

    Jacob Leal, Sandrine; Napoletano, Mauro

    2016-01-01

    We investigate the effects of different regulatory policies directed towards high-frequency trading (HFT) through an agent-based model of a limit order book able to generate flash crashes as the result of the interactions between low- and high-frequency (HF) traders. We analyze the impact of the imposition of minimum resting times, of circuit breakers (both ex-post and ex-ante types), of cancellation fees and of transaction taxes on asset price volatility and on the occurrence ...

  2. Linking Bayesian and agent-based models to simulate complex social-ecological systems in semi-arid regions

    OpenAIRE

    Pope, Aloah J.; Gimblett, Randy

    2015-01-01

    Interdependencies of ecologic, hydrologic, and social systems challenge traditional approaches to natural resource management in semi-arid regions. As a complex social-ecological system, water demands in the Sonoran Desert from agricultural and urban users often conflicts with water needs for its ecologically-significant riparian corridors. To explore this system, we developed an agent-based model to simulate complex feedbacks between human decisions and environmental conditions in the Rio So...

  3. Linking Bayesian and agent-based models to simulate complex social-ecological systems in semi-arid regions

    OpenAIRE

    Pope, Aloah J.; Randy eGimblett

    2015-01-01

    Interdependencies of ecologic, hydrologic, and social systems challenge traditional approaches to natural resource management in semi-arid regions. As a complex social-ecological system, water demands in the Sonoran Desert from agricultural and urban users often conflicts with water needs for its ecologically-significant riparian corridors. To explore this system, we developed an agent-based model to simulate complex feedbacks between human decisions and environmental conditions in the Rio ...

  4. Deciphering chemokine properties by a hybrid agent-based model of Aspergillus fumigatus infection in human alveoli

    OpenAIRE

    Pollmächer, Johannes; Figge, Marc Thilo

    2015-01-01

    The ubiquitous airborne fungal pathogen Aspergillus fumigatus is inhaled by humans every day. In the lung, it is able to quickly adapt to the humid environment and, if not removed within a time frame of 4–8 h, the pathogen may cause damage by germination and invasive growth. Applying a to-scale agent-based model of human alveoli to simulate early A. fumigatus infection under physiological conditions, we recently demonstrated that alveolar macrophages require chemotactic cues to accomplish the...

  5. An agent-based model to study customers' engagement with brands from a service-dominant logic perspective

    OpenAIRE

    Terano, Takao; Rajapakse, Chathura

    2014-01-01

    We present an Agent-based Model to study customers' engagement with brands from a Service-Dominant Logic perspective. Customer Engagement has gained attention recently in the study of customer loyalty as a process that enables to understand and measure the impact of the depths of customers emotional responses to consumption situations on their intention to retain with a particular brand. However, there is no adequate research that deeply investigate the process of engagement, especially in dy...

  6. On Agent-Based Software Engineering

    OpenAIRE

    Jennings, N. R.

    2000-01-01

    Agent-based computing represents an exciting new synthesis both for Artificial Intelligence (AI) and, more generally, Computer Science. It has the potential to significantly improve the theory and the practice of modeling, designing, and implementing computer systems. Yet, to date, there has been little systematic analysis of what makes the agent-based approach such an appealing and powerful computational model. Moreover, even less effort has been devoted to discussing the inherent disadvanta...

  7. Agent-based modeling as a research method for exploring joint decision making in organizations – a distributed cognition perspective

    DEFF Research Database (Denmark)

    Thomsen, Svend Erik

    2016-01-01

    This paper proposes an agent-based model to explore aspects of decision making in organizations from a distributed cognition perspective. Within distributed cognition research cognition is conceptualized as a process that takes place - not only within individuals’ minds but also between them, as...... they interact with each other. This means that the interactions between individuals impact both the outcome of the decision process and the individuals’ cognition, which in turn will impact their subsequent decisions. The paper outlines how this dynamic and complex task can be modeled taking into...

  8. Leveraging social influence to address overweight and obesity using agent-based models: the role of adolescent social networks.

    Science.gov (United States)

    Zhang, J; Tong, L; Lamberson, P J; Durazo-Arvizu, R A; Luke, A; Shoham, D A

    2015-01-01

    The prevalence of adolescent overweight and obesity (hereafter, simply "overweight") in the US has increased over the past several decades. Individually-targeted prevention and treatment strategies targeting individuals have been disappointing, leading some to propose leveraging social networks to improve interventions. We hypothesized that social network dynamics (social marginalization; homophily on body mass index, BMI) and the strength of peer influence would increase or decrease the proportion of network member (agents) becoming overweight over a simulated year, and that peer influence would operate differently in social networks with greater overweight. We built an agent-based model (ABM) using results from R-SIENA. ABMs allow for the exploration of potential interventions using simulated agents. Initial model specifications were drawn from Wave 1 of the National Longitudinal Study of Adolescent Health (Add Health). We focused on a single saturation school with complete network and BMI data over two waves (n = 624). The model was validated against empirical observations at Wave 2. We focused on overall overweight prevalence after a simulated year. Five experiments were conducted: (1) changing attractiveness of high-BMI agents; (2) changing homophily on BMI; (3) changing the strength of peer influence; (4) shifting the overall BMI distribution; and (5) targeting dietary interventions to highly connected individuals. Increasing peer influence showed a dramatic decrease in the prevalence of overweight; making peer influence negative (i.e., doing the opposite of friends) increased overweight. However, the effect of peer influence varied based on the underlying distribution of BMI; when BMI was increased overall, stronger peer influence increased proportion of overweight. Other interventions, including targeted dieting, had little impact. Peer influence may be a viable target in overweight interventions, but the distribution of body size in the population needs to

  9. Integrating the simulation of domestic water demand behaviour to an urban water model using agent based modelling

    Science.gov (United States)

    Koutiva, Ifigeneia; Makropoulos, Christos

    2015-04-01

    The urban water system's sustainable evolution requires tools that can analyse and simulate the complete cycle including both physical and cultural environments. One of the main challenges, in this regard, is the design and development of tools that are able to simulate the society's water demand behaviour and the way policy measures affect it. The effects of these policy measures are a function of personal opinions that subsequently lead to the formation of people's attitudes. These attitudes will eventually form behaviours. This work presents the design of an ABM tool for addressing the social dimension of the urban water system. The created tool, called Urban Water Agents' Behaviour (UWAB) model, was implemented, using the NetLogo agent programming language. The main aim of the UWAB model is to capture the effects of policies and environmental pressures to water conservation behaviour of urban households. The model consists of agents representing urban households that are linked to each other creating a social network that influences the water conservation behaviour of its members. Household agents are influenced as well by policies and environmental pressures, such as drought. The UWAB model simulates behaviour resulting in the evolution of water conservation within an urban population. The final outcome of the model is the evolution of the distribution of different conservation levels (no, low, high) to the selected urban population. In addition, UWAB is implemented in combination with an existing urban water management simulation tool, the Urban Water Optioneering Tool (UWOT) in order to create a modelling platform aiming to facilitate an adaptive approach of water resources management. For the purposes of this proposed modelling platform, UWOT is used in a twofold manner: (1) to simulate domestic water demand evolution and (2) to simulate the response of the water system to the domestic water demand evolution. The main advantage of the UWAB - UWOT model

  10. Using agent based modeling to assess the effect of increased Bus Rapid Transit system infrastructure on walking for transportation.

    Science.gov (United States)

    Lemoine, Pablo D; Cordovez, Juan Manuel; Zambrano, Juan Manuel; Sarmiento, Olga L; Meisel, Jose D; Valdivia, Juan Alejandro; Zarama, Roberto

    2016-07-01

    The effect of transport infrastructure on walking is of interest to researchers because it provides an opportunity, from the public policy point of view, to increase physical activity (PA). We use an agent based model (ABM) to examine the effect of transport infrastructure on walking. Particular relevance is given to assess the effect of the growth of the Bus Rapid Transit (BRT) system in Bogotá on walking. In the ABM agents are assigned a home, work location, and socioeconomic status (SES) based on which they are assigned income for transportation. Individuals must decide between the available modes of transport (i.e., car, taxi, bus, BRT, and walking) as the means of reaching their destination, based on resources and needed travel time. We calibrated the model based on Bogota's 2011 mobility survey. The ABM results are consistent with previous empirical findings, increasing BRT access does indeed increase the number of minutes that individuals walk for transportation, although this effect also depends on the availability of other transport modes. The model indicates a saturation process: as more BRT lanes are added, the increment in minutes walking becomes smaller, and eventually the walking time decreases. Our findings on the potential contribution of the expansion of the BRT system to walking for transportation suggest that ABMs may prove helpful in designing policies to continue promoting walking. PMID:27012602

  11. Modelling Inductive Charging of Battery Electric Vehicles using an Agent-Based Approach

    Directory of Open Access Journals (Sweden)

    Zain Ul Abedin

    2014-09-01

    Full Text Available The introduction of battery electric vehicles (BEVs could help to reduce dependence on fossil fuels and emissions from transportation and as such increase energy security and foster sustainable use of energy resources. However a major barrier to the introduction of BEVs is their limited battery capacity and long charging durations. To address these issues of BEVs several solutions are proposed such as battery swapping and fast charging stations. However apart from these stationary modes of charging, recently a new mode of charging has been introduced which is called inductive charging. This allows charging of BEVs as they drive along roads without the need of plugs, using induction. But it is unclear, if and how such technology could be utilized best. In order to investigate the possible impact of the introduction of such inductive charging infrastructure, its potential and its optimal placement, a framework for simulating BEVs using a multi-agent transport simulation was used. This framework was extended by an inductive charging module and initial test runs were performed. In this paper we present the simulation results of these preliminary tests together with analysis which suggests that battery sizes of BEVs could be reduced even if inductive charging technology is implemented only at a small number of high traffic volume links. The paper also demonstrates that our model can effectively support policy and decision making for deploying inductive charging infrastructure.

  12. Agent-based modeling approach of immune defense against spores of opportunistic human pathogenic fungi

    Directory of Open Access Journals (Sweden)

    Christian eTokarski

    2012-04-01

    Full Text Available Opportunistic human pathogenic fungi like the ubiquitous fungus Aspergillus fumigatus are a majorthreat to immunocompromised patients. An impaired immune system renders the body vulnerable to inva-sive mycoses that often lead to the death of the patient. While the number of immunocompromised patientsis rising with medical progress, the process and dynamics of defence against invaded and ready to germinatefungal conidia are still insufficiently understood.Besides macrophages, neutrophil granulocytes form an important line of defence in that they clear conidia.Live imaging shows the interaction of those phagocytes and conidia as a dynamic process of touching, drag-ging and phagocytosis. To unravel strategies of phagocytes on the hunt for conidia an agent-based modelingapproach is used, implemented in NetLogo. Different modes of movement of phagocytes are tested regard-ing their clearing efficiency: random walk, short term persistence in their recent direction, chemotaxis ofchemokines excreted by conidia and communication between phagocytes.

  13. Application potential of Agent Based Simulation and Discrete Event Simulation in Enterprise integration modelling concepts

    Directory of Open Access Journals (Sweden)

    Paul-Eric DOSSOU

    2013-07-01

    Full Text Available Normal 0 21 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} This paper aims to present the dilemma of simulation tool selection. Authors discuss the examples of methodologies of enterprises architectures (CIMOSA and GRAI where agent approach is used to solve planning and managing problems. Actually simulation is widely used and practically only one tool which can enable verification of complex systems. Many companies face the problem, which simulation tool is appropriate to use for verification. Selected tools based on ABS and DES are presented. Some tools combining DES and ABS approaches are described. Authors give some recommendation on selection process.

  14. Application potential of Agent Based Simulation and Discrete Event Simulation in Enterprise integration modelling concepts

    Directory of Open Access Journals (Sweden)

    Pawel PAWLEWSKI

    2012-07-01

    Full Text Available Normal 0 21 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin; mso-ansi-language:EN-US;} This paper aims to present the dilemma of simulation tool selection. Authors discuss the examples of methodologies of enterprises architectures (CIMOSA and GRAI where agent approach is used to solve planning and managing problems. Actually simulation is widely used and practically only one tool which can enable verification of complex systems. Many companies face the problem, which simulation tool is appropriate to use for verification. Selected tools based on ABS and DES are presented. Some tools combining DES and ABS approaches are described. Authors give some recommendation on selection process.

  15. Using uncertainty and sensitivity analyses in socioecological agent-based models to improve their analytical performance and policy relevance.

    Directory of Open Access Journals (Sweden)

    Arika Ligmann-Zielinska

    Full Text Available Agent-based models (ABMs have been widely used to study socioecological systems. They are useful for studying such systems because of their ability to incorporate micro-level behaviors among interacting agents, and to understand emergent phenomena due to these interactions. However, ABMs are inherently stochastic and require proper handling of uncertainty. We propose a simulation framework based on quantitative uncertainty and sensitivity analyses to build parsimonious ABMs that serve two purposes: exploration of the outcome space to simulate low-probability but high-consequence events that may have significant policy implications, and explanation of model behavior to describe the system with higher accuracy. The proposed framework is applied to the problem of modeling farmland conservation resulting in land use change. We employ output variance decomposition based on quasi-random sampling of the input space and perform three computational experiments. First, we perform uncertainty analysis to improve model legitimacy, where the distribution of results informs us about the expected value that can be validated against independent data, and provides information on the variance around this mean as well as the extreme results. In our last two computational experiments, we employ sensitivity analysis to produce two simpler versions of the ABM. First, input space is reduced only to inputs that produced the variance of the initial ABM, resulting in a model with output distribution similar to the initial model. Second, we refine the value of the most influential input, producing a model that maintains the mean of the output of initial ABM but with less spread. These simplifications can be used to 1 efficiently explore model outcomes, including outliers that may be important considerations in the design of robust policies, and 2 conduct explanatory analysis that exposes the smallest number of inputs influencing the steady state of the modeled system.

  16. An Agent-Based Computational Model for China’s Stock Market and Stock Index Futures Market

    Directory of Open Access Journals (Sweden)

    Hai-Chuan Xu

    2014-01-01

    Full Text Available This study presents an agent-based computational cross market model for Chinese equity market structure, which includes both stocks and CSI 300 index futures. In this model, we design several stocks and one index future to simulate this structure. This model allows heterogeneous investors to make investment decisions with restrictions including wealth, market trading mechanism, and risk management. Investors’ demands and order submissions are endogenously determined. Our model successfully reproduces several key features of the Chinese financial markets including spot-futures basis distribution, bid-ask spread distribution, volatility clustering, and long memory in absolute returns. Our model can be applied in cross market risk control, market mechanism design, and arbitrage strategies analysis.

  17. Agent-based modeling for the landuse change of hunter-gather societies and the impacts on biodiversity in Guyana

    Science.gov (United States)

    Iwamura, T.; Fragoso, J.; Lambin, E.

    2012-12-01

    The interactions with animals are vital to the Amerindian, indigenous people, of Rupunini savannah-forest in Guyana. Their connections extend from basic energy and protein resource to spiritual bonding through "paring" to a certain animal in the forest. We collected extensive dataset of 23 indigenous communities for 3.5 years, consisting 9900 individuals from 1307 households, as well as animal observation data in 8 transects per communities (47,000 data entries). In this presentation, our research interest is to model the driver of land use change of the indigenous communities and its impacts on the ecosystem in the Rupunini area under global change. Overarching question we would like to answer with this program is to find how and why "tipping-point" from hunting gathering society to the agricultural society occurs in the future. Secondary question is what is the implication of the change to agricultural society in terms of biodiversity and carbon stock in the area, and eventually the well-being of Rupunini people. To answer the questions regarding the society shift in agriculture activities, we built as simulation with Agent-Based Modeling (Multi Agents Simulation). We developed this simulation by using Netlogo, the programming environment specialized for spatially explicit agent-based modeling (ABM). This simulation consists of four different process in the Rupunini landscape; forest succession, animal population growth, hunting of animals, and land clearing for agriculture. All of these processes are carried out by a set of computational unit, called "agents". In this program, there are four types of agents - patches, villages, households, and animals. Here, we describe the impacts of hunting on the biodiversity based on actual demographic data from one village named Crush Water. Animal population within the hunting territory of the village stabilized but Agouti/Paca dominates the landscape with little population of armadillos and peccaries. White-tailed deers

  18. Modeling urban expansion policy scenarios using an agent-based approach for Guangzhou Metropolitan Region of China

    Directory of Open Access Journals (Sweden)

    Guangjin Tian

    2014-09-01

    Full Text Available Policy makers and the human decision processes of urban planning have an impact on urban expansion. The behaviors and decision modes of regional authority, real estate developer, resident, and farmer agents and their interactions can be simulated by the analytical hierarchy process (AHP method. The driving factors are regressed with urban dynamics instead of static land-use types. Agents’ behaviors and decision modes have an impact on the urban dynamic pattern by adjusting parameter weights. We integrate an agent-based model (ABM with AHP to investigate a complex decision-making process and future urban dynamic processes. Three policy scenarios for baseline development, rapid development, and green land protection have been applied to predict the future development patterns of the Guangzhou metropolitan region. A future policy scenario analysis can help policy makers to understand the possible results. These individuals can adjust their policies and decisions according to their different objectives.

  19. Agent-based simulation of animal behaviour

    OpenAIRE

    Jonker, C.M.; Treur, J.

    1998-01-01

    In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active, social and adaptive behaviour. The compositional development method for multi-agent systems DESIRE and its software environment supports the conceptual and detailed design, and execution of these models. Experiments reported in the literature on animal behaviour have been simulated for a num...

  20. Modelling and simulation of electrical energy systems through a complex systems approach using agent-based models. Case study: Under-frequency load shedding for refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Kremers, Enrique [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany). European Inst. for Energy Research (EIFER); Gonzalez de Durana, Jose Maria; Barambones, Oscar [Universidad del Pais Vasco, Vitoria (Spain). Escuela Universitaria de Ingenieria de Vitoria-Gasteiz

    2013-09-01

    One of the ways of studying complex systems is through modelling and simulation, which are used as tools to represent these systems in a virtual environment. Current advances in computing performance (which has been a major constraint in this field for some time) allow for the simulation these kinds of systems within reasonable time horizons. One of the tools for simulating complex systems is agent-based modelling. This individual-centric approach is based on autonomous entities that can interact with each other, thus modelling the system in a disaggregated way. Agent-based models can be coupled with other modelling methods, such as continuous models and discrete events, which can be embedded or run in parallel to the multi-agent system. When representing the electrical energy system in a systemic and multi-layered way, it is treated as a true socio-technical system, in which not only technical models are taken into account, but also socio-behavioural ones. In this work, a number of different models for the parts of an electrical system are presented, related to production, demand and storage. The models are intended to be as simple as possible in order to be simulated in an integrated framework representing the system as a whole. Furthermore, the models allow the inclusion of social behaviour and other, not purely engineering-related aspects of the system, which have to be considered from a complex point of view. (orig.)

  1. Improving energy efficiency and smart grid program analysis with agent-based end-use forecasting models

    International Nuclear Information System (INIS)

    Electric utilities and regulators face difficult challenges evaluating new energy efficiency and smart grid programs prompted, in large part, by recent state and federal mandates and financial incentives. It is increasingly difficult to separate electricity use impacts of individual utility programs from the impacts of increasingly stringent appliance and building efficiency standards, increasing electricity prices, appliance manufacturer efficiency improvements, energy program interactions and other factors. This study reviews traditional approaches used to evaluate electric utility energy efficiency and smart-grid programs and presents an agent-based end-use modeling approach that resolves many of the shortcomings of traditional approaches. Data for a representative sample of utility customers in a Midwestern US utility are used to evaluate energy efficiency and smart grid program targets over a fifteen-year horizon. Model analysis indicates that a combination of the two least stringent efficiency and smart grid program scenarios provides peak hour reductions one-third greater than the most stringent smart grid program suggesting that reductions in peak demand requirements are more feasible when both efficiency and smart grid programs are considered together. Suggestions on transitioning from traditional end-use models to agent-based end-use models are provided.

  2. Improving energy efficiency and smart grid program analysis with agent-based end-use forecasting models

    International Nuclear Information System (INIS)

    Electric utilities and regulators face difficult challenges evaluating new energy efficiency and smart grid programs prompted, in large part, by recent state and federal mandates and financial incentives. It is increasingly difficult to separate electricity use impacts of individual utility programs from the impacts of increasingly stringent appliance and building efficiency standards, increasing electricity prices, appliance manufacturer efficiency improvements, energy program interactions and other factors. This study reviews traditional approaches used to evaluate electric utility energy efficiency and smart-grid programs and presents an agent-based end-use modeling approach that resolves many of the shortcomings of traditional approaches. Data for a representative sample of utility customers in a Midwestern US utility are used to evaluate energy efficiency and smart grid program targets over a fifteen-year horizon. Model analysis indicates that a combination of the two least stringent efficiency and smart grid program scenarios provides peak hour reductions one-third greater than the most stringent smart grid program suggesting that reductions in peak demand requirements are more feasible when both efficiency and smart grid programs are considered together. Suggestions on transitioning from traditional end-use models to agent-based end-use models are provided. (author)

  3. Ligand based validated comparative chemometric modeling and pharmacophore mapping of aurone derivatives as antimalarial agents.

    Science.gov (United States)

    Adhikari, Nilanjan; Halder, Amit Kumar; Mondal, Chanchal; Jha, Tarun

    2013-09-01

    Chloroquine resistance is nowadays a great problem. Aurone derivatives are effective against chloroquine resistant parasite. Ligand based validated comparative chemometric modeling through 2D-QSAR and kNN-MFA 3DQSAR studies as well as common feature 3D pharmacophore mapping were done on thirtyfive aurone derivatives having antimalarial activity. Statistically significant 2D-QSAR models were generated on unsplitted as well as splitted dataset by MLR and PLS technique. The MLR model of the unsplitted method was validated by two-deep cross validation and 10 fold cross validation for determining the predictive ability. The PLS technique of the unsplitted method was done to compare the significance of these methods. In the splitted method, model was developed on the training set by Y-based ranking method by using the same descriptors and was validated on fifty pairs of the test and the training sets by k-MCA technique. These models generated by using the same descriptors were well validated irrespective of MLR as well as PLS analysis of unsplitted as well as splitted methods and are showing similar results. Therefore, these descriptors and model generated were reliable and robust. The kNN-MFA 3D-QSAR models were generated by three variable selection methods: genetic algorithm, simulated annealing and stepwise regression. The kNN-MFA 3D-QSAR results support the 2D QSAR data and in turn validate the earlier observed SAR results. Common feature 3D-pharmacophore generation was performed on these compounds to validate both 2D and 3D-QSAR studies as well as the earlier observed SAR data. The work highlights the required structural features for the higher antimalarial activity. PMID:24010937

  4. Intelligent Agent-Based System for Digital Library Information Retrieval

    Institute of Scientific and Technical Information of China (English)

    师雪霖; 牛振东; 宋瀚涛; 宋丽哲

    2003-01-01

    A new information search model is reported and the design and implementation of a system based on intelligent agent is presented. The system is an assistant information retrieval system which helps users to search what they need. The system consists of four main components: interface agent, information retrieval agent, broker agent and learning agent. They collaborate to implement system functions. The agents apply learning mechanisms based on an improved ID3 algorithm.

  5. Construct validity of agent-based simulation of normative behaviour

    OpenAIRE

    Xenitidou, M; Elsenbroich, C

    2011-01-01

    In this paper we assess the construct validity and theoretical emdeddedness of agent-based models of normative behaviour drawing on experimental social psychology. We contend that social psychology and agent-based modelling share the focus of ‘observing’ the processes and outcomes of the interaction of individual agents. The paper focuses on two from a taxonomy of agent-based models of normative behaviour. This enables the identification of the assumptions the models are built on and in turn,...

  6. The EMO-Model: An Agent-Based Model of Primate Social Behavior Regulated by Two Emotional Dimensions, Anxiety-FEAR and Satisfaction-LIKE

    NARCIS (Netherlands)

    Evers, Ellen; de Vries, Han; Spruijt, Berry; Sterck, Elisabeth

    2014-01-01

    Agent-based models provide a promising tool to investigate the relationship between individuals’ behavior and emerging group-level patterns. An individual’s behavior may be regulated by its emotional state and its interaction history with specific individuals. Emotional bookkeeping is a candidate me

  7. Towards a dynamic assessment of raw materials criticality: Linking agent-based demand — With material flow supply modelling approaches

    Energy Technology Data Exchange (ETDEWEB)

    Knoeri, Christof, E-mail: c.knoeri@leeds.ac.uk [Sustainability Research Institute, School of Earth and Environment, University of Leeds, LS5 9JT Leeds (United Kingdom); Wäger, Patrick A.; Stamp, Anna; Althaus, Hans-Joerg [Technology and Society Laboratory, Empa, Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Duebendorf (Switzerland); Weil, Marcel [Institute for Technology Assessment and Systems Analysis, Karlsruhe Institute of Technology (KIT), D-76021 Karlsruhe (Germany); Helmholtz-Institute Ulm for Electrochemical Energy Storage, Albert-Einstein-Allee 11, 89081 Ulm (Germany)

    2013-09-01

    Emerging technologies such as information and communication-, photovoltaic- or battery technologies are expected to increase significantly the demand for scarce metals in the near future. The recently developed methods to evaluate the criticality of mineral raw materials typically provide a ‘snapshot’ of the criticality of a certain material at one point in time by using static indicators both for supply risk and for the impacts of supply restrictions. While allowing for insights into the mechanisms behind the criticality of raw materials, these methods cannot account for dynamic changes in products and/or activities over time. In this paper we propose a conceptual framework intended to overcome these limitations by including the dynamic interactions between different possible demand and supply configurations. The framework integrates an agent-based behaviour model, where demand emerges from individual agent decisions and interaction, into a dynamic material flow model, representing the materials' stocks and flows. Within the framework, the environmental implications of substitution decisions are evaluated by applying life-cycle assessment methodology. The approach makes a first step towards a dynamic criticality assessment and will enhance the understanding of industrial substitution decisions and environmental implications related to critical metals. We discuss the potential and limitation of such an approach in contrast to state-of-the-art methods and how it might lead to criticality assessments tailored to the specific circumstances of single industrial sectors or individual companies. - Highlights: ► Current criticality assessment methods provide a ‘snapshot’ at one point in time. ► They do not account for dynamic interactions between demand and supply. ► We propose a conceptual framework to overcomes these limitations. ► The framework integrates an agent-based behaviour model with a dynamic material flow model. ► The approach proposed

  8. Towards a dynamic assessment of raw materials criticality: Linking agent-based demand — With material flow supply modelling approaches

    International Nuclear Information System (INIS)

    Emerging technologies such as information and communication-, photovoltaic- or battery technologies are expected to increase significantly the demand for scarce metals in the near future. The recently developed methods to evaluate the criticality of mineral raw materials typically provide a ‘snapshot’ of the criticality of a certain material at one point in time by using static indicators both for supply risk and for the impacts of supply restrictions. While allowing for insights into the mechanisms behind the criticality of raw materials, these methods cannot account for dynamic changes in products and/or activities over time. In this paper we propose a conceptual framework intended to overcome these limitations by including the dynamic interactions between different possible demand and supply configurations. The framework integrates an agent-based behaviour model, where demand emerges from individual agent decisions and interaction, into a dynamic material flow model, representing the materials' stocks and flows. Within the framework, the environmental implications of substitution decisions are evaluated by applying life-cycle assessment methodology. The approach makes a first step towards a dynamic criticality assessment and will enhance the understanding of industrial substitution decisions and environmental implications related to critical metals. We discuss the potential and limitation of such an approach in contrast to state-of-the-art methods and how it might lead to criticality assessments tailored to the specific circumstances of single industrial sectors or individual companies. - Highlights: ► Current criticality assessment methods provide a ‘snapshot’ at one point in time. ► They do not account for dynamic interactions between demand and supply. ► We propose a conceptual framework to overcomes these limitations. ► The framework integrates an agent-based behaviour model with a dynamic material flow model. ► The approach proposed makes

  9. An agent-based approach with collaboration among agents. Estimation of wholesale electricity price on PJM and artificial data generated by a mean reverting model

    International Nuclear Information System (INIS)

    This study examines the performance of MAIS (Multi-Agent Intelligent Simulator) equipped with various learning capabilities. In addition to the learning capabilities, the proposed MAIS incorporates collaboration among agents. The proposed MAIS is applied to estimate a dynamic change of wholesale electricity price in PJM (Pennsylvania-New Jersey-Mainland) and an artificial data set generated by a mean reverting model. Using such different types of data sets, the methodological validity of MAIS is confirmed by comparing it with other well-known alternatives in computer science. This study finds that the MAIS needs to incorporate both the mean reverting model and the collaboration behavior among agents in order to enhance its estimation capability. The MAIS discussed in this study will provide research on energy economics with a new numerical capability that can investigate a dynamic change of not only wholesale electricity price but also speculation and learning process of traders. (author)

  10. Germanic Settlement Structure in the Middle Danube Region as a Complex System of Agent-Based Modeling

    Czech Academy of Sciences Publication Activity Database

    Vlach, Marek

    2015-01-01

    Roč. 42, č. 1 (2015), s. 741-748. ISSN 0323-9535. [International Congress of Roman Frontier Studies /22./. Ruse, 06.09.2012-11.09.2012] R&D Projects: GA ČR GA404/09/1054 Grant ostatní: Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M300011201 Institutional support: RVO:68081758 Keywords : Roman period * Middle Danube region * Germanic settlement structure * Agent Based Modeling * archaeological demography Subject RIV: AC - Archeology, Anthropology, Ethnology

  11. A platform for analyzing access-friendly transportations for elderly people using GIS on agent-based model

    OpenAIRE

    Daito, Masatora; Tanida, Noriyuki

    2014-01-01

    In this research, we construct a platform for analyzing access-friendly transportation for elderly people using GIS on agent-based model. Our interest is related to an aging world population and well-being of elderly people. We use GIS data of Ibaraki city Japan and study the outing rate of elderly people. We defined the number of times of outing per seven days as outing rate. The simulation is performed 63 times. It is comparable to 63days (nine weeks). As the results of simulation showed th...

  12. Information Service Model with Mobile Agent Supported

    Institute of Scientific and Technical Information of China (English)

    邹涛; 王继成; 张福炎

    2000-01-01

    Mobile Agent is a kind of novel agent technology characterized by mobile, intelligent, parallel and asynchronous computing. In this paper, a new information service model that adopts mobile agent technology is introduced first,and then an experimental system DOLTRIA system that is implemented based on the model is described. The DOLTRIA system implemented by WWW framework and Java can search for relevant HTML documents on a set of Web servers. The result of experiments shows that performance improvement can be achieved by this model, and both the elapsed time and network traffic are reduced significantly.

  13. Developing an Agent-based Model for the Depot-based Water Allocation System in the Bakken Field in Western North Dakota

    Science.gov (United States)

    Lin, T.; Lin, Z.; Lim, S.; Borders, M.

    2015-12-01

    The oil production at the Bakken Shale increased more than ten times from 2008 to 2013 due to technological advancement in hydraulic fracturing and North Dakota has become the second largest oil producing state in the U.S. behind only Texas since 2012. On average it requires about 2-4 million gallons of freshwater to complete one oil well in the Bakken field and the number of oil well completions (i.e., hydraulic fracturing) in the Bakken field increased from 500 in 2008 to 2085 in 2013. A large quantity of freshwater used for hydraulic fracturing renders a significant impact on water resource management in the semi-arid region. A novel water allocation system - water depots - was spontaneously created to distribute surface and ground water for industrial uses. A GIS-based multi-agent model is developed to simulate the emergent patterns and dynamics of the water depot-based water allocation system and to explore its economic and environmental consequences. Four different types of water depot are defined as agents and water price, climate condition, water source, geology, and other physical and economic constraints are considered in the model. Decentralized optimization algorithm will be used to determine the agents' behaviors. The agent-based model for water depots will be coupled with hydrological models to improve the region's water resources management.

  14. Evaluating the Impacts of an Agricultural Water Market in the Guadalupe River Basin, Texas: An Agent-based Modeling Approach

    Science.gov (United States)

    Du, E.; Cai, X.; Minsker, B. S.

    2014-12-01

    Agriculture comprises about 80 percent of the total water consumption in the US. Under conditions of water shortage and fully committed water rights, market-based water allocations could be promising instruments for agricultural water redistribution from marginally profitable areas to more profitable ones. Previous studies on water market have mainly focused on theoretical or statistical analysis. However, how water users' heterogeneous physical attributes and decision rules about water use and water right trading will affect water market efficiency has been less addressed. In this study, we developed an agent-based model to evaluate the benefits of an agricultural water market in the Guadalupe River Basin during drought events. Agricultural agents with different attributes (i.e., soil type for crops, annual water diversion permit and precipitation) are defined to simulate the dynamic feedback between water availability, irrigation demand and water trading activity. Diversified crop irrigation rules and water bidding rules are tested in terms of crop yield, agricultural profit, and water-use efficiency. The model was coupled with a real-time hydrologic model and run under different water scarcity scenarios. Preliminary results indicate that an agricultural water market is capable of increasing crop yield, agricultural profit, and water-use efficiency. This capability is more significant under moderate drought scenarios than in mild and severe drought scenarios. The water market mechanism also increases agricultural resilience to climate uncertainty by reducing crop yield variance in drought events. The challenges of implementing an agricultural water market under climate uncertainty are also discussed.

  15. Agent Based Patient Scheduling Using Heuristic Algorithm

    Directory of Open Access Journals (Sweden)

    Juliet A Murali

    2010-01-01

    Full Text Available This paper describes about an agent based approach to patient scheduling using experience based learning. A heuristic algorithm is also used in the proposed framework. The evaluation on different learning techniques shows that the experience based learning (EBL gives better solution. The processing time decreases as the experience increases. The heuristic algorithm make use of EBL in calculating the processing time. The main objective of this patient scheduling system is to reduce the waiting time of patient in hospitals and to complete their treatment in minimum required time. The framework is implemented in JADE. In this approach the patients and resources are represented as patient agents (PA and resource agents (RA respectively. Even though mathematical model give optimal solution, the computational complexity increases for large size problems. Heuristic solution gives better solution for large size problems. The comparisons of the proposed framework with other scheduling rules shows that an agent based approach to patient scheduling using EBL is better.

  16. A place for agent-based models. Comment on "Statistical physics of crime: A review" by M.R. D'Orsogna and M. Perc

    Science.gov (United States)

    Barbaro, Alethea

    2015-03-01

    Agent-based models have been widely applied in theoretical ecology to explain migrations and other collective animal movements [2,5,8]. As D'Orsogna and Perc have expertly highlighted in [6], the recent emergence of crime modeling has opened another interesting avenue for mathematical investigation. The area of crime modeling is particularly suited to agent-based models, because these models offer a great deal of flexibility within the model and also ease of communication among criminologist, law enforcement and modelers.

  17. A georeferenced Agent-Based Model to analyze the climate change impacts on the Andorra winter tourism

    CERN Document Server

    Pons-Pons, M; Rosas-Casals, M; Sureda, B; Jover, E

    2011-01-01

    This study presents a georeferenced agent-based model to analyze the climate change impacts on the ski industry in Andorra and the effect of snowmaking as future adaptation strategy. The present study is the first attempt to analyze the ski industry in the Pyrenees region and will contribute to a better understanding of the vulnerability of Andorran ski resorts and the suitability of snowmaking as potential adaptation strategy to climate change. The resulting model can be used as a planning support tool to help local stakeholders understand the vulnerability and potential impacts of climate change. This model can be used in the decision-making process of designing and developing appropriate sustainable adaptation strategies to future climate variability.

  18. Population Control for Multi-agent Based Topical Crawlers

    OpenAIRE

    Mouton, Alban; Marteau, Pierre-François

    2008-01-01

    International audience The use of multi-agent topical Web crawlers based on the endogenous fitness model raises the problem of controling the population of agents. We tackle this question through an energy based model to balance the reproduction/life expectency of agents. Our goal is to simplify the tuning of parameters and to optimize the use of ressources available for the crawling. We introduce an energy based model designed to control the number of agents according to the precision of ...

  19. An Agent-Based Analysis of Tax Compliance for Turkey

    OpenAIRE

    M. Oguz ARSLAN; Ozgur Ican

    2013-01-01

    An agent-based tax compliance model for Turkey is developed in this paper. In this model, four kinds of agent archetypes as honest, strategic, defiant, and random are employed. The model is used for simulating evolutionary changes in tax compliance behavior of a population of 10,000 taxpayer agents. The implementation of the model via four simulation scenarios points out that an agent-based evolutionary strategy simulation for Turkish case is valid. Also, the neighbourhood effect is not found...

  20. Multi-agent model-based historical cropland spatial pattern reconstruction for 1661-1952, Shandong Province, China

    Science.gov (United States)

    Yang, Xuhong; Jin, Xiaobin; Du, Xindong; Xiang, Xiaomin; Han, Juan; Shan, Wei; Fan, Yeting; Zhou, Yinkang

    2016-08-01

    To advance the research of global land use/cover change (LUCC), biodiversity, global carbon cycle, and other aspects of the earth system, it is essential to reconstruct changes in historical cropland cover with long time series and high-resolution grid. Currently, it is a general approach which is based on the view of combining the overall control of cropland area, selecting grid of high land suitability, and 'top-down' decision-making behaviors to reconstruct the historical cropland. Considering various factors that influenced cropland distribution, including behavioral agent's selection by itself and the limitation of nature and human factors, a spatiotemporal dynamical reconstruction model of historical cropland based on the multi-agent systems has been developed from the perspective of 'bottom-up', which combine macroscopic and microscopic decision-making behaviors of agents to simulate the government and farmer autonomously implementing the selection behaviors of farming area. Taking Shandong Province as the study area, this model was used to imitate its cropland spatiotemporal pattern with 1 km grid-resolution from 1661 combining the contemporary pattern and reconstructed amount of historical cropland as a maximum potential scope and control variable of reconstruction model, respectively, furthermore, followed the accuracy valuation and comparative analysis. The reconstructed results show that: 1) It is properly suitable for Multi-Agent to simulate and reconstruct the spatial distribution of historical cropland; 2) compared with historical map data sets (1930s) from the view of point to point, the correctly classified producer accuracy, user accuracy and overall accuracy of reconstructed result totally up to 59.09%, 80.62% and 62.31%, respectively, and shows our reconstruction map achieved a better agreement with the historical maps; 3) from the view of grid-level or county-level, our reconstruction approach can effectively keep away from the grid with

  1. A process-based model of soil structure to assess the impact of biological agents, climate and reduced tillage

    Science.gov (United States)

    Le Couteulx, Alexis; Pérès, Guénola; Wolf, Cédric; Hallaire, Vincent

    2014-05-01

    Soil structure can be defined as the spatial arrangement of voids and solids in soil. It is a dynamic soil property due to agents' activity such as (i) mechanical action of soil tillage (ii) earthworms through their burrowing activity and faeces production and (iii) climate impact due to rain or temperature. Soil structure is often studied because of its impacts on soil functional properties, e.g. water percolation, soil water conductivity. In a context of farming practices shift towards non-ploughing techniques, it is needed to evaluate impacts on soil structure and consequently on its functional properties. Existing models have adopted two strategies to simulate soil structure: (i) to use of measured parameters to adjust a theoretical model or (ii) to build a soil structure by simulating processes that are its base. The first strategy does not deal with the difficulty to access soil structure by itself because input measured parameters are needed. The second one starts from either a virgin structure or a structure coming from strategy (i). This starting structure is then altered according to one structuring agent. At present, there is a need for such dynamic models of soil structure. They must be explicit (3D) and common for a large set of structuring agents too. They must also deal with several issues: e.g. to memorize the many voids and solids building up the soil structure or the need to be fast enough to simulate soil structure dynamics for a month, a year, etc. A first proposal, based on the strong assumption that soil is fractal, was made by Marilleau et al. (2008). In our model three structuring agents were chosen: tillage, earthworm's activity and solid particles settlement due to climate. It first focuses on the building of a computerized soil structure which is a common base to simulate the agents. It aims at being as generic as possible by using an object-oriented structure. The concept of voxel is used to split the soil into elementary units and each

  2. A Collective Case Study of Secondary Students' Model-Based Inquiry on Natural Selection through Programming in an Agent-Based Modeling Environment

    Science.gov (United States)

    Xiang, Lin

    This is a collective case study seeking to develop detailed descriptions of how programming an agent-based simulation influences a group of 8 th grade students' model-based inquiry (MBI) by examining students' agent-based programmable modeling (ABPM) processes and the learning outcomes. The context of the present study was a biology unit on natural selection implemented in a charter school of a major California city during spring semester of 2009. Eight 8th grade students, two boys and six girls, participated in this study. All of them were low socioeconomic status (SES). English was a second language for all of them, but they had been identified as fluent English speakers at least a year before the study. None of them had learned either natural selection or programming before the study. The study spanned over 7 weeks and was comprised of two study phases. In phase one the subject students learned natural selection in science classroom and how to do programming in NetLogo, an ABPM tool, in a computer lab; in phase two, the subject students were asked to program a simulation of adaptation based on the natural selection model in NetLogo. Both qualitative and quantitative data were collected in this study. The data resources included (1) pre and post test questionnaire, (2) student in-class worksheet, (3) programming planning sheet, (4) code-conception matching sheet, (5) student NetLogo projects, (6) videotaped programming processes, (7) final interview, and (8) investigator's field notes. Both qualitative and quantitative approaches were applied to analyze the gathered data. The findings suggested that students made progress on understanding adaptation phenomena and natural selection at the end of ABPM-supported MBI learning but the progress was limited. These students still held some misconceptions in their conceptual models, such as the idea that animals need to "learn" to adapt into the environment. Besides, their models of natural selection appeared to be

  3. Applying an agent-based model of agricultural terraces coupled with a landscape evolution model to explore the impact of human decision-making on terraced terrain

    Science.gov (United States)

    Glaubius, Jennifer

    2016-04-01

    Agricultural terraces impact landscape evolution as a result of long-term human-landscape interactions, including decisions regarding terrace maintenance and abandonment. Modeling simulations are often employed to examine the sensitivity of landscapes to various factors, such as rainfall and land cover. Landscape evolution models, erosion models, and hydrological models have all previously been used to simulate the impact of agricultural terrace construction on terrain evolution, soil erosion, and hydrological connectivity. Human choices regarding individual terraces have not been included in these models to this point, despite recent recognition that maintenance and abandonment decisions alter transport and storage patterns of soil and water in terraced terrain. An agent-based model of human decisions related to agricultural terraces is implemented based on a conceptual model of agricultural terrace life cycle stages created from a literature review of terracing impacts. The agricultural terracing agent-based model is then coupled with a landscape evolution model to explore the role of human decisions in the evolution of terraced landscapes. To fully explore this type of co-evolved landscape, human decision-making and its feedbacks must be included in landscape evolution models. Project results may also have implications for management of terraced terrain based on how human choices in these environments affect soil loss and land degradation.

  4. Agent-Based Modeling in Supply Chain Management:A Genetic Algorithm and Fuzzy Logic Approach

    OpenAIRE

    Meriem DJENNAS; Benbouziane, Mohamed; Djennas, Mustapha

    2012-01-01

    In today’s global market, reaching a competitive advantage by integrating firms in a supply chain management strategy becomes a key success for any firm seeking to survive in a complex environment. However, as interactions among agents in the supply chain management (SCM) remain unpredictable, simulation appears as a powerful tool aiming to predict market behavior and agents’ performance levels. This paper discusses the issues of supply chain management and the requirements for su...

  5. Non-lethal control of the cariogenic potential of an agent-based model for dental plaque.

    Science.gov (United States)

    Head, David A; Marsh, Phil D; Devine, Deirdre A

    2014-01-01

    Dental caries or tooth decay is a prevalent global disease whose causative agent is the oral biofilm known as plaque. According to the ecological plaque hypothesis, this biofilm becomes pathogenic when external challenges drive it towards a state with a high proportion of acid-producing bacteria. Determining which factors control biofilm composition is therefore desirable when developing novel clinical treatments to combat caries, but is also challenging due to the system complexity and the existence of multiple bacterial species performing similar functions. Here we employ agent-based mathematical modelling to simulate a biofilm consisting of two competing, distinct types of bacterial populations, each parameterised by their nutrient uptake and aciduricity, periodically subjected to an acid challenge resulting from the metabolism of dietary carbohydrates. It was found that one population was progressively eliminated from the system to give either a benign or a pathogenic biofilm, with a tipping point between these two fates depending on a multiplicity of factors relating to microbial physiology and biofilm geometry. Parameter sensitivity was quantified by individually varying the model parameters against putative experimental measures, suggesting non-lethal interventions that can favourably modulate biofilm composition. We discuss how the same parameter sensitivity data can be used to guide the design of validation experiments, and argue for the benefits of in silico modelling in providing an additional predictive capability upstream from in vitro experiments. PMID:25144538

  6. Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling.

    Science.gov (United States)

    Shin, Sangmi; Park, Seongha; Kim, Yongho; Matson, Eric T

    2016-01-01

    Recently, commercial unmanned aerial systems (UAS) have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM) technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment. PMID:27110790

  7. Real-Time Agent-Based Modeling Simulation with in-situ Visualization of Complex Biological Systems

    Science.gov (United States)

    Seekhao, Nuttiiya; Shung, Caroline; JaJa, Joseph; Mongeau, Luc; Li-Jessen, Nicole Y. K.

    2016-01-01

    We present an efficient and scalable scheme for implementing agent-based modeling (ABM) simulation with In Situ visualization of large complex systems on heterogeneous computing platforms. The scheme is designed to make optimal use of the resources available on a heterogeneous platform consisting of a multicore CPU and a GPU, resulting in minimal to no resource idle time. Furthermore, the scheme was implemented under a client-server paradigm that enables remote users to visualize and analyze simulation data as it is being generated at each time step of the model. Performance of a simulation case study of vocal fold inflammation and wound healing with 3.8 million agents shows 35× and 7× speedup in execution time over single-core and multi-core CPU respectively. Each iteration of the model took less than 200 ms to simulate, visualize and send the results to the client. This enables users to monitor the simulation in real-time and modify its course as needed. PMID:27547508

  8. Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling

    Directory of Open Access Journals (Sweden)

    Sangmi Shin

    2016-04-01

    Full Text Available Recently, commercial unmanned aerial systems (UAS have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment.

  9. Non-lethal control of the cariogenic potential of an agent-based model for dental plaque.

    Directory of Open Access Journals (Sweden)

    David A Head

    Full Text Available Dental caries or tooth decay is a prevalent global disease whose causative agent is the oral biofilm known as plaque. According to the ecological plaque hypothesis, this biofilm becomes pathogenic when external challenges drive it towards a state with a high proportion of acid-producing bacteria. Determining which factors control biofilm composition is therefore desirable when developing novel clinical treatments to combat caries, but is also challenging due to the system complexity and the existence of multiple bacterial species performing similar functions. Here we employ agent-based mathematical modelling to simulate a biofilm consisting of two competing, distinct types of bacterial populations, each parameterised by their nutrient uptake and aciduricity, periodically subjected to an acid challenge resulting from the metabolism of dietary carbohydrates. It was found that one population was progressively eliminated from the system to give either a benign or a pathogenic biofilm, with a tipping point between these two fates depending on a multiplicity of factors relating to microbial physiology and biofilm geometry. Parameter sensitivity was quantified by individually varying the model parameters against putative experimental measures, suggesting non-lethal interventions that can favourably modulate biofilm composition. We discuss how the same parameter sensitivity data can be used to guide the design of validation experiments, and argue for the benefits of in silico modelling in providing an additional predictive capability upstream from in vitro experiments.

  10. Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling

    Science.gov (United States)

    Shin, Sangmi; Park, Seongha; Kim, Yongho; Matson, Eric T.

    2016-01-01

    Recently, commercial unmanned aerial systems (UAS) have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM) technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment. PMID:27110790

  11. Phenotypic transition maps of 3D breast acini obtained by imaging-guided agent-based modeling

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Jonathan; Enderling, Heiko; Becker-Weimann, Sabine; Pham, Christopher; Polyzos, Aris; Chen, Chen-Yi; Costes, Sylvain V

    2011-02-18

    We introduce an agent-based model of epithelial cell morphogenesis to explore the complex interplay between apoptosis, proliferation, and polarization. By varying the activity levels of these mechanisms we derived phenotypic transition maps of normal and aberrant morphogenesis. These maps identify homeostatic ranges and morphologic stability conditions. The agent-based model was parameterized and validated using novel high-content image analysis of mammary acini morphogenesis in vitro with focus on time-dependent cell densities, proliferation and death rates, as well as acini morphologies. Model simulations reveal apoptosis being necessary and sufficient for initiating lumen formation, but cell polarization being the pivotal mechanism for maintaining physiological epithelium morphology and acini sphericity. Furthermore, simulations highlight that acinus growth arrest in normal acini can be achieved by controlling the fraction of proliferating cells. Interestingly, our simulations reveal a synergism between polarization and apoptosis in enhancing growth arrest. After validating the model with experimental data from a normal human breast line (MCF10A), the system was challenged to predict the growth of MCF10A where AKT-1 was overexpressed, leading to reduced apoptosis. As previously reported, this led to non growth-arrested acini, with very large sizes and partially filled lumen. However, surprisingly, image analysis revealed a much lower nuclear density than observed for normal acini. The growth kinetics indicates that these acini grew faster than the cells comprising it. The in silico model could not replicate this behavior, contradicting the classic paradigm that ductal carcinoma in situ is only the result of high proliferation and low apoptosis. Our simulations suggest that overexpression of AKT-1 must also perturb cell-cell and cell-ECM communication, reminding us that extracellular context can dictate cellular behavior.

  12. Intelligent agent based control of TL-1

    International Nuclear Information System (INIS)

    The Agent based control of complex systems is becoming popular due to its ability to identify the critical situation and its ability to dynamically search for the best available solution to the problem with constrained optimization of the inputs. In this paper we are presenting the architecture of intelligent agent for automatic control of power supplies of TL-1 (Transfer Line 1) to maximise the injection process against the changes in the input beam obtained from Microtron. The paper discusses the results obtained by applying this agent architecture to the accelerator model comprises of Microtron output, TL-1 and booster. (author)

  13. Modeling the 2014 Ebola Virus Epidemic – Agent-Based Simulations, Temporal Analysis and Future Predictions for Liberia and Sierra Leone

    OpenAIRE

    Siettos, Constantinos; Anastassopoulou, Cleo; Russo, Lucia; Grigoras, Christos; Mylonakis, Eleftherios

    2015-01-01

    We developed an agent-based model to investigate the epidemic dynamics of Ebola virus disease (EVD) in Liberia and Sierra Leone from May 27 to December 21, 2014. The dynamics of the agent-based simulator evolve on small-world transmission networks of sizes equal to the population of each country, with adjustable densities to account for the effects of public health intervention policies and individual behavioral responses to the evolving epidemic. Based on time series of the official case cou...

  14. The Tragedy of the Park: an Agent-based Model of Endogenous and Exogenous Institutions for Forest Management

    Directory of Open Access Journals (Sweden)

    Elena Vallino

    2014-03-01

    Full Text Available Many scholars of common-pool resources have found that institutions might solve the tragedy of the commons. I address a particular situation of natural resource management: that of a protected area. In this situation, interests differ. Local rural inhabitants care about the quality of their environment but also need to exploit the resources for livelihood reasons. An external entity such as the State, a donor, an NGO, or some combination thereof decides that there is a need for nature conservation in that area. Because of some evidence of failure for a strictly top-down conservationist approach, the external entity decides to apply the concept of participatory conservation: the local inhabitants become stakeholders in the management of the area and become collectively responsible for conservation, with rights to exploit the resources up to some degree. I argue that project designers try to find a solution to nature conservation through the creation of a situation of a commons: creating a community that has rights and duties toward a particular natural area that is endowed with some resources. Many scholars rely mostly on institutions that are endogenously created within the users' community to avoid the tragedy of the commons. However, what happens if institutions are imposed? In participatory conservation initiatives, the community has collective rights over the resources, and in this sense, the issue of endogenous rules for the commons management is relevant. However, the level to which the community should exploit the resource is usually imposed by the external project designers. Using agent-based simulations, I develop a theoretical model to look at the consequences of an imposed institution on the state of a forest and on the users' profit, taking into account the possibilities of violating the imposed rules and facing enforcement. I compare the consequences of this imposed institution with those deriving from an endogenously created

  15. Frequency analysis of tick quotes on the foreign exchange market and agent-based modeling: A spectral distance approach

    CERN Document Server

    Sato, A H

    2006-01-01

    The high frequency financial data of the foreign exchange market (EUR/CHF, EUR/GBP, EUR/JPY, EUR/NOK, EUR/SEK, EUR/USD, NZD/USD, USD/CAD, USD/CHF, USD/JPY, USD/NOK, and USD/SEK) are analyzed by utilizing the Kullback-Leibler divergence between two normalized spectrograms of the tick frequency. We detect and characterize temporal structure variations of the similarity between currency pairs. A simple agent-based model that N market participants exchange M currency pairs is proposed. The equation for the tick frequency is approximately derived in the theoretical manner. From the analysis of this model the spectral distance of the tick frequency is associated with the similarity of behavior (perception and decision) of the market participants to exchange these currency pairs.

  16. Entrainment and Control of Bacterial Populations: An in Silico Study over a Spatially Extended Agent Based Model.

    Science.gov (United States)

    Mina, Petros; Tsaneva-Atanasova, Krasimira; Bernardo, Mario di

    2016-07-15

    We extend a spatially explicit agent based model (ABM) developed previously to investigate entrainment and control of the emergent behavior of a population of synchronized oscillating cells in a microfluidic chamber. Unlike most of the work in models of control of cellular systems which focus on temporal changes, we model individual cells with spatial dependencies which may contribute to certain behavioral responses. We use the model to investigate the response of both open loop and closed loop strategies, such as proportional control (P-control), proportional-integral control (PI-control) and proportional-integral-derivative control (PID-control), to heterogeinities and growth in the cell population, variations of the control parameters and spatial effects such as diffusion in the spatially explicit setting of a microfluidic chamber setup. We show that, as expected from the theory of phase locking in dynamical systems, open loop control can only entrain the cell population in a subset of forcing periods, with a wide variety of dynamical behaviors obtained outside these regions of entrainment. Closed-loop control is shown instead to guarantee entrainment in a much wider region of control parameter space although presenting limitations when the population size increases over a certain threshold. In silico tracking experiments are also performed to validate the ability of classical control approaches to achieve other reference behaviors such as a desired constant output or a linearly varying one. All simulations are carried out in BSim, an advanced agent-based simulator of microbial population which is here extended ad hoc to include the effects of control strategies acting onto the population. PMID:27110835

  17. Modelling skylarks (Alauda arvensis) to predict impacts of changes in land management and policy: development and testing of an agent-based model

    DEFF Research Database (Denmark)

    Topping, Christopher John; Odderskær, Peter; Kahlert, Johnny Abildgaard

    2013-01-01

    Agent-based simulation models provide a viable approach for developing applied models of species and systems for predictive management. However, there has been some reluctance to use these models for policy applications due to complexity and the need for improved testing and communication...... necessary to simulate their behaviour. Population responses emerge from individuals interacting with each other and the environment. Model testing was carried out using pattern-oriented modelling. The testing procedure was based on the model’s ability to represent detailed real world patterns...... of the models. We present the development and testing of a comprehensive model for Skylark (Alauda arvensis) in Danish agricultural landscapes. The model is part of the ALMaSS system, which considers not only individual skylarks, but also the detailed dynamic environment from which they obtain the information...

  18. Modelling and Simulating of Risk Behaviours in Virtual Environments Based on Multi-Agent and Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Linqin Cai

    2013-11-01

    Full Text Available Due to safety and ethical issues, traditional experimental approaches to modelling underground risk behaviours can be costly, dangerous and even impossible to realize. Based on multi-agent technology, a virtual coalmine platform for risk behaviour simulation is presented to model and simulate the human-machine- environment related risk factors in underground coalmines. To reveal mine workers’ risk behaviours, a fuzzy emotional behaviour model is proposed to simulate underground miners’ responding behaviours to potential hazardous events based on cognitive appraisal theories and fuzzy logic techniques. The proposed emotion model can generate more believable behaviours for virtual miners according to personalized emotion states, internal motivation needs and behaviour selection thresholds. Finally, typical accident cases of underground hazard spotting and locomotive transport were implemented. The behaviour believability of virtual miners was evaluated with a user assessment method. Experimental results show that the proposed models can create more realistic and reasonable behaviours in virtual coalmine environments, which can improve miners’ risk awareness and further train miners’ emergent decision-making ability when facing unexpected underground situations.

  19. Adaptive management in crop pest control in the face of climate variability: an agent-based modeling approach

    Directory of Open Access Journals (Sweden)

    François Rebaudo

    2015-06-01

    Full Text Available Climate changes are occurring rapidly at both regional and global scales. Farmers are faced with the challenge of developing new agricultural practices to help them to cope with unpredictable changes in environmental, social, and economic conditions. Under these conditions, adaptive management requires a farmer to learn by monitoring provisional strategies and changing conditions, and then incrementally adjust management practices in light of new information. Exploring adaptive management will increase our understanding of the underlying processes that link farmer societies with their environment across space and time, while accounting for the impacts of an unpredictable climate. Here, we assessed the impacts of temperature and crop price, as surrogates for climate and economic changes, on farmers' adaptive management in crop pest control using an agent-based modeling approach. Our model simulated an artificial society of farmers that relied on field data obtained in the Ecuadorian Andes. Farmers were represented as heterogeneous autonomous agents who interact with and influence each other, and who are capable of adapting to changing environmental conditions. The results of our simulation suggest that variable temperatures led to less effective pest control strategies than those used under stable temperatures. Moreover, farmers used information gained through their own past experience or through interactions with other farmers to initiate an adaptive management approach. At a broader scale, this study generates more than an increased understanding of adaptive management; it highlights how people depend on one another to manage common problems.

  20. An integrated modeling framework of socio-economic, biophysical, and hydrological processes in Midwest landscapes: Remote sensing data, agro-hydrological model, and agent-based model

    Science.gov (United States)

    Ding, Deng

    Intensive human-environment interactions are taking place in Midwestern agricultural systems. An integrated modeling framework is suitable for predicting dynamics of key variables of the socio-economic, biophysical, hydrological processes as well as exploring the potential transitions of system states in response to changes of the driving factors. The purpose of this dissertation is to address issues concerning the interacting processes and consequent changes in land use, water balance, and water quality using an integrated modeling framework. This dissertation is composed of three studies in the same agricultural watershed, the Clear Creek watershed in East-Central Iowa. In the first study, a parsimonious hydrologic model, the Threshold-Exceedance-Lagrangian Model (TELM), is further developed into RS-TELM (Remote Sensing TELM) to integrate remote sensing vegetation data for estimating evapotranspiration. The goodness of fit of RS-TELM is comparable to a well-calibrated SWAT (Soil and Water Assessment Tool) and even slightly superior in capturing intra-seasonal variability of stream flow. The integration of RS LAI (Leaf Area Index) data improves the model's performance especially over the agriculture dominated landscapes. The input of rainfall datasets with spatially explicit information plays a critical role in increasing the model's goodness of fit. In the second study, an agent-based model is developed to simulate farmers' decisions on crop type and fertilizer application in response to commodity and biofuel crop prices. The comparison between simulated crop land percentage and crop rotations with satellite-based land cover data suggest that farmers may be underestimating the effects that continuous corn production has on yields (yield drag). The simulation results given alternative market scenarios based on a survey of agricultural land owners and operators in the Clear Creek Watershed show that, farmers see cellulosic biofuel feedstock production in the form