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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Agentbaserade beslutsstöds framtida roll i strategisk stadsplanering.

Hallberg, Ida January 2022 (has links)
In community planning, accessibility is a recurring concept. The concept has also time and time again proved to have a great impact on how well an area develops. Its important role in community planning has resulted in a large amount of research in the field. The meaning and definition of the term varies markedly depending on the context and there are several different methods and tools for measuring accessibility. This creates a problem for decision makers to be able to take the planning options that will generate the greatest availability. Agent-based decision support systems are a decision support system that is currently receiving a great deal of attention in the literature. Real systems of interest are implemented in a simulation program to be able to support decision-making. The purpose of the study is to examine the decision materials for community planning that are used to increase different perspectives on accessibility and how agent-based modeling could be used. In the study, a categorization has been developed based on different models to measure accessibility based on existing literature. The study is based on a deductive approach and builds on existing literature. Through interviews with regions, municipalities and the Swedish Transport Administration, the current situation for the decision basis for community planning that is used to increase different perspectives on accessibility has been mapped. The interviews and categorization will also look at the future role of agent-based modeling as decision support in planning different perspectives on accessibility. The study shows that there is a need for clearer routines linked to the work with accessibility and an increased use of GIS, this could be obtained from an ABDS tool. Several advantages of ABDS systems have been identified, such as clarifying the concept of accessibility and how it is affected by different alternatives. There are also several future challenges for the use of the system, such as the problem that selected algorithms have a major impact on the results. / I samhällsplanering är tillgänglighet ett återkommande begrepp. Begreppet har även gång på gång visat sig ha en stor påverkan för hur väl ett område utvecklas. Dess viktiga roll i samhällsplaneringen har resulterat i en stor mängd forskning inom området. Begreppets innebörd och definition varierar markant beroende på sammanhang och det finns flertal olika metoder och verktyg för att mäta tillgänglighet. Detta skapar en problematik för beslutsfattare att kunna ta de planeringsalternativ som kommer att generera den största tillgängligheten. Agentbaserade beslutsstödsystem (ABDS) är ett beslutsstödsystem som för närvarande uppmärksammas väldigt mycket i litteraturen. Verkliga system av intresse implementeras i ett simuleringsprogram för att kunna stödja beslutsfattande. Syftet med studien är att undersöka beslutsunderlagen för samhällsplanering som används för att öka olika perspektiv på tillgänglighet samt hur agentbaserad modellering skulle kunna nyttjas. I studien har en formell värderingsmodell tagits fram utifrån olika perspektiv på tillgänglighet baserat på existerande litteratur. Studien baseras på en deduktiv ansats och bygger vidare från existerande litteratur. Genom intervjuer med regioner, kommuner och Trafikverket har nuläget för beslutsunderlagen för samhällsplanering som används för att öka olika perspektiv på tillgänglighet kartlagts. Intervjuerna och värderingsmodellen kommer även se till den framtida roll som agentbaserad modellerings som beslutsstöd har vid planering av olika perspektiv på tillgänglighet. Studien visar på att det finns ett behov för tydligare rutiner kopplade till arbetet med tillgänglighet samt en ökad användning av GIS, detta skulle kunna erhållas av ett ABDS-verktyg. Det har identifierats flertal fördelar med ABDS-system såsom att tydliggöra begreppet tillgänglighet och hur den påverkas av olika alternativ. Det finns även flertal framtida utmaningar för användning av systemet som t.ex. problemet att utvalda algoritmer har en stor inverkan på resultaten.
72

Integration of Passenger and Freight Transportation using Autonomous Shuttles: A Simulation Study on Sustainability-Related KPIs

Staritz, Johannes, Sand, Helen, Auf der Landwehr, Marvin, von Viebahn, Christoph, Wartenberg, Maylin 14 June 2023 (has links)
Autonomous and integrated passenger and freight transport (APFIT) is a promising approach to tackle both, traffic and last-mile-related issues such as environmental emissions, social and spatial conflicts or operational inefficiencies. By conducting an agent-based simulation, we shed light on this widely unexplored research topic and provide first indications regarding influential target figures of such a system in the rural area of Sarstedt, Germany. Our results show that larger fleets entail inefficiencies due to suboptimal utilization of monetary and material resources and increase traffic volume while higher amounts of unused vehicles may exacerbate spatial conflicts. Nevertheless, to fit the given demand within our study area, a comparatively large fleet of about 25 vehicles is necessary to provide reliable service, assuming maximum passenger waiting times of six minutes to the expense of higher standby times, rebalancing effort, and higher costs for vehicle acquisition and maintenance.
73

AN AGENT-BASED SIMULATION OF INVENTORY MANAGEMENT WITH NEGATIVE SHORTAGE COSTS AND UNCERTAIN QUALITY AND LEAD TIMES

Khalaf, Ramez 02 September 2010 (has links)
No description available.
74

在虛擬共同基金市場中模擬小群體社會學習機制的研究 / The simulation of social learning mechanism with small groups in artificial mutual fund market

林瑞益, Lin, Jui Yi Unknown Date (has links)
個人投資理財是近年來熱門的議題,而國內與此相關的研究大都集中在投資績效的提升、投資標的之選擇、資產配置比例與影響投資績效的變數等,較少在探討個人的投資準則與社會關係學習所造成的投資績效差異。本論文利用代理人為基礎的模擬方式(Agent-Based Simulation)與動態虛擬社會關係,模擬共同基金投資市場的交易行為,讓模型中的一個或數個群體裡的所有投資人除了可以依循著自身的投資準則進行投資外,亦有機會藉由虛擬社會關係學習到其他投資人的投資準則,進而提升投資績效。在實驗中,我們針對不同的學習頻率及學習參數觀察學習的效果。我們發現,當有虛擬社會關係學習模式且學習評估頻率為每月一次時,有助於整體投資績效的提升。 / Personal investment is a topic that has attracted much attention in recent years. However, the researches and applications related to this topic are usually concentrated in the area of increase investment performance, portfolio, investment selection, and critical investment performance factors. Less are about investment criteria and social learning that affect investment performance. In this thesis, we use agent-based simulation with dynamic virtual social relationship to simulate artificial mutual fund market. The investors in the model can invest by their own criteria, and learn other agent’s criteria via virtual social relationship to increase investment performance. We use different sets of parameters in the experiments to observe how these parameters affect the result. Our experiments revealed that our new model with social learning mechanism and a learning evaluation frequency of a month, the overall investment performance can be significantly improved.
75

Inserção de jogadores virtuais em jogos de papéis para uso em sistemas de apoio à decisão em grupo: um experimento no domínio da gestão de recursos naturais. / Insertion of virtual players in role playing games to use in group decision support systems: an experiment in natural resources management.

Adamatti, Diana Francisca 05 June 2007 (has links)
Este trabalho propoe a definicao de uma arquitetura para incorporar jogadores virtuais em uma classe de Sistemas de Apoio a Decisao em Grupos (SADs-G), baseados na utilizacao conjunta de Simulacao Baseada em Multiagentes (MABS) e Jogos de Papeis (RPGs). Estas duas tecnicas, MABS e RPGs, vem sendo utilizadas de forma integrada ha alguns anos devido a capacidade de discussao e aprendizado dos RPG e da capacidade dinamica de MABS. Os jogadores virtuais definidos devem ter a capacidade de tomada de decisao e de comunicacao entre si e com os jogadores reais durante as negociacoes. Os principais aspectos discutidos neste trabalho sao: i) se os jogadores virtuais definidos possuem comportamentos nao-triviais perante aos jogadores reais; ii) se continua ocorrendo o processo de negociacao entre os jogadores, sejam eles reais ou virtuais; iii) se a realizacao de um jogo de forma eletronica (via computador) dificulta a interacao entre os jogadores. De forma a discutir estes aspectos, duas instancias de SADs-G foram implementadas no contexto da Gestao de Recursos Naturais, pois neste dominio o processo de negociacao e extremamente importante e complexo. / This thesis proposes the definition of an architecture to insert virtual players in a particular subclass of Group Decision Support Systems (GDSS), that uses Multi-Agent-Based Simulation (MABS) and Role-Playing Games (RPGs) techniques in an integrated way. These techniques can bring interesting results, since it is possible to join the dynamic capacity of MABS with the discussion and learning capacity of RPGs. The defined virtual players must make decisions and communicate with each other and with the real players during the negotiation process. In this work, the main aspects discussed are the following: i) can virtual players have no-trivial behavior in the face of real players? ii) is the negotiation process between all players (virtual or real) still happening when virtual players are inserted? iii) do electronic games make more difficult the interaction between players? In order to discuss these aspects, two instances of GDSSs were developed in the natural resources management domain. This domain was chosen because its negotiation process is both very important and complex.
76

Inserção de jogadores virtuais em jogos de papéis para uso em sistemas de apoio à decisão em grupo: um experimento no domínio da gestão de recursos naturais. / Insertion of virtual players in role playing games to use in group decision support systems: an experiment in natural resources management.

Diana Francisca Adamatti 05 June 2007 (has links)
Este trabalho propoe a definicao de uma arquitetura para incorporar jogadores virtuais em uma classe de Sistemas de Apoio a Decisao em Grupos (SADs-G), baseados na utilizacao conjunta de Simulacao Baseada em Multiagentes (MABS) e Jogos de Papeis (RPGs). Estas duas tecnicas, MABS e RPGs, vem sendo utilizadas de forma integrada ha alguns anos devido a capacidade de discussao e aprendizado dos RPG e da capacidade dinamica de MABS. Os jogadores virtuais definidos devem ter a capacidade de tomada de decisao e de comunicacao entre si e com os jogadores reais durante as negociacoes. Os principais aspectos discutidos neste trabalho sao: i) se os jogadores virtuais definidos possuem comportamentos nao-triviais perante aos jogadores reais; ii) se continua ocorrendo o processo de negociacao entre os jogadores, sejam eles reais ou virtuais; iii) se a realizacao de um jogo de forma eletronica (via computador) dificulta a interacao entre os jogadores. De forma a discutir estes aspectos, duas instancias de SADs-G foram implementadas no contexto da Gestao de Recursos Naturais, pois neste dominio o processo de negociacao e extremamente importante e complexo. / This thesis proposes the definition of an architecture to insert virtual players in a particular subclass of Group Decision Support Systems (GDSS), that uses Multi-Agent-Based Simulation (MABS) and Role-Playing Games (RPGs) techniques in an integrated way. These techniques can bring interesting results, since it is possible to join the dynamic capacity of MABS with the discussion and learning capacity of RPGs. The defined virtual players must make decisions and communicate with each other and with the real players during the negotiation process. In this work, the main aspects discussed are the following: i) can virtual players have no-trivial behavior in the face of real players? ii) is the negotiation process between all players (virtual or real) still happening when virtual players are inserted? iii) do electronic games make more difficult the interaction between players? In order to discuss these aspects, two instances of GDSSs were developed in the natural resources management domain. This domain was chosen because its negotiation process is both very important and complex.
77

Modélisation des déplacements d'animaux dans un espace géographique : analyse et simulation / Modelling animal movements on a geographical space : analyses and simulation

Jolivet, Laurence 20 May 2014 (has links)
Une des préoccupations de la société est de trouver un compromis entre le développement des territoires et la protection de la faune sauvage. La prise en compte des déplacements des animaux lors de projets d’aménagement nécessite de connaître les comportements des différentes espèces et de définir ce qui a une influence sur leur localisation et sur la sélection de leur lieu de vie. Notre objectif est de pouvoir représenter les déplacements d’animaux sur un espace géographique précisément décrit afin ensuite de simuler et d’évaluer les conséquences des aménagements.Nous avons commencé par analyser l’influence des éléments du paysage sur les déplacements à partir de localisations connues d’animaux comme des traces GPS (suivis menés par l’ELIZ, l’ANSES, l’ONCFS, l’INRA)et de données de description de l’espace notamment la BD TOPO®. Les cas d’étude correspondent à des milieux différents et à trois espèces : renard, chevreuil et cerf. Nous avons pu confirmer le rôle de certains caractères de l’espace selon les cas d’étude. Par exemple les préférences spatiales lors des déplacements des renards en milieu périurbain semblent se porter sur la végétation arborée et des lieux peu occupés par les hommes pendant certaines parties de la journée (parcs, zones d’activités, le long des voies ferrées). Concernant les cervidés en milieu forestier, la pente et le type de peuplement paraissent avoir le plus d’influence sur les déplacements.À l’aide des connaissances extraites par les analyses et de la littérature, nous avons défini et implémenté dans la plateforme GeOxygene un modèle de simulation de déplacements d’animaux. Les trajectoires sont construites par une approche agent reprenant le comportement spatial selon l’espèce et l’influence des éléments du paysage favorables ou faisant obstacle. Nous effectuons une analyse critique de notre modèle puis nous proposons des pistes d’enrichissement à l’aide de la comparaison avec les observations et le retour des écologues. Enfin des scénarios d’aménagement sont testés dans le but de mettre en évidence leur impact et leur efficacité. / Finding compromises between human development and wildlife protection is one concern of society.Taking into account animal movements in planning projects requires some knowledge on species behaviours and on what determines their localizations and their habitat places. Our goal is to be able to represent animal movements on an accurate geographical space in order to simulate and to evaluate the consequences of planning decisions. We first analysed how the features of the landscape influence movements from collected localizations on animals, for example GPS tracks (studies of ELIZ, ANSES, ONCFS, INRA) and from data describing spacesuch as BD TOPO®. The studied cases are about several types of environment and three species: red fox,roe deer and red deer. We found some results that confirm the role played by the spatial features,depending on the studied cases. For instance in a periurban environment, foxes seem to be more inwooded patches and in places with few human activities during some parts of the day (squares, areas with industrial or commercial activities, sides of railways). In a forested environment, deers are more likely to be influenced by slope and forest stands. Thanks to knowledge from data analyses and to literature, we defined a simulation model for animalmovements. We implemented it in the GeOxygene platform. The trajectories are built with an agent approach by taking into account the spatial behaviour of the species and the influence of elements that favour or hinder movements. We proposed a critical view of the modelling choices and some improvements from the comparison with observations and experts advices. Then, scenarios within frastructures are defined so that to identify their impact and their efficiency.
78

A Model Driven Method to Design and Analyze Secure System-of-Systems Architectures : Application to Predict Cascading Attacks in Smart Buildings. / Une Méthode Dirigée par les Modèles pour la Conception et l'Analyse des Architectures Sécurisées des Systèmes-de-Systèmes : Application à la Prédiction des Attaques en Cascade dans les Bâtiments Intelligents.

El Hachem, Jamal 07 December 2017 (has links)
Le Système-de-Systèmes (SdS) devient l'un des principaux paradigmes pour l'ingénieriedes solutions de la prochaine génération, telles que les villes intelligentes, les bâtiments intelligents,les systèmes médicaux, les systèmes d'interventions d'urgence et les systèmes de défense. Parconséquent, l'intérêt apporté aux SdS, leur architecture et surtout leur sécurité est en croissancecontinue. Cependant, les caractéristiques de différenciation des SdS, telles que le comportementémergent et l'indépendance managériale et opérationnelle de ses constituants, peuvent introduiredes problèmes spécifiques qui rendent leurs modélisation, simulation et analyse de sécurité un déficritique. Dans cette thèse, nous étudions comment les approches du génie logiciel peuvent êtreétendues pour modéliser et analyser les architectures sécurisées de SdS, afin de découvrir lesattaques à fort impact (attaques en cascade) tôt à la phase d'architecture. Pour atteindre notreobjectif, nous proposons une méthode d'Ingénierie Dirigée par les Modèles (IDM), nommée Systems-of-Systems Security (SoSSec), qui comprend: (1) un langage de modélisation (SoSSecML) pour lamodélisation des architectures sécurisées des SdS, et une extension des Systèmes Multi-Agents(SMA) pour l'analyse des architectures sécurisées des SdS; (2) les outils correspondants: un éditeurgraphique, un générateur de code, une extension de la plate-forme Java Agent Development (JADE)pour la simulation des SMA, un outil personnalisé pour l'enregistrement des résultats de simulation;et (3) un processus pour guider l'utilisation de la méthode SoSSec. Pour illustrer notre approche,nous avons réalisé un cas d'étude sur un bâtiment intelligent réel, le bâtiment de l'école de santé del'Université d'Adélaïde (AHMS). / Systems-of-Systems (SoS) is becoming one of the major paradigm forengineering next generation solutions such as smart cities, smart buildings, health-care, emergencyresponse and defense. Therefore, there is a growing interest in SoS, their architecture and speciallytheir security. However, SoS differentiating characteristics, such as emergent behavior andmanagerial and operational independence of its constituents, may introduce specific issues thatmake their security modeling, simulation and analysis a critical challenge. In this thesis we investigatehow Software Engineering approaches can be extended to model and analyze secure SoS solutionsfor discovering high impact attacks (cascading attacks) at the architecture stage. In order to achieveour objective, we propose a Model Driven Engineering method, Systems-of-Systems Security(SoSSec), that comprises: (1) a modeling description language (SoSSecML) for secure SoS modelingand an extension of Multi-Agent Systems (MAS) for secure SoS architecture analysis, (2) thecorresponding tools: a graphical editor, a code generator, an extension of the Java AgentDevelopment (JADE) MAS simulation framework, a custom logging tool, (3) an utilization process toguide the use of the SoSSec method. To illustrate our approach we conducted a case study on a reallifesmart building SoS, the Adelaide University Health and Medical School (AHMS).
79

Proceedings of the Workshop on Membrane Computing, WMC 2016.

Konur, Savas, Gheorghe, Marian 08 1900 (has links)
yes / This Workshop on Membrane Computing, at the Conference of Unconventional Computation and Natural Computation (UCNC), 12th July 2016, Manchester, UK, is the second event of this type after the Workshop at UCNC 2015 in Auckland, New Zealand*. Following the tradition of the 2015 Workshop the Proceedings are published as technical report. The Workshop consisted of one invited talk and six contributed presentations (three full papers and three extended abstracts) covering a broad spectrum of topics in Membrane Computing, from computational and complexity theory to formal verification, simulation and applications in robotics. All these papers – see below, but the last extended abstract, are included in this volume. The invited talk given by Rudolf Freund, “P SystemsWorking in Set Modes”, presented a general overview on basic topics in the theory of Membrane Computing as well as new developments and future research directions in this area. Radu Nicolescu in “Distributed and Parallel Dynamic Programming Algorithms Modelled on cP Systems” presented an interesting dynamic programming algorithm in a distributed and parallel setting based on P systems enriched with adequate data structure and programming concepts representation. Omar Belingheri, Antonio E. Porreca and Claudio Zandron showed in “P Systems with Hybrid Sets” that P systems with negative multiplicities of objects are less powerful than Turing machines. Artiom Alhazov, Rudolf Freund and Sergiu Ivanov presented in “Extended Spiking Neural P Systems with States” new results regading the newly introduced topic of spiking neural P systems where states are considered. “Selection Criteria for Statistical Model Checker”, by Mehmet E. Bakir and Mike Stannett, presented some early experiments in selecting adequate statistical model checkers for biological systems modelled with P systems. In “Towards Agent-Based Simulation of Kernel P Systems using FLAME and FLAME GPU”, Raluca Lefticaru, Luis F. Macías-Ramos, Ionuţ M. Niculescu, Laurenţiu Mierlă presented some of the advatages of implementing kernel P systems simulations in FLAME. Andrei G. Florea and Cătălin Buiu, in “An Efficient Implementation and Integration of a P Colony Simulator for Swarm Robotics Applications" presented an interesting and efficient implementation based on P colonies for swarms of Kilobot robots. *http://ucnc15.wordpress.fos.auckland.ac.nz/workshop-on-membrane-computingwmc- at-the-conference-on-unconventional-computation-natural-computation/
80

Analysis of Single Echelon Logistics Model for Delivering Temperature Sensitive E-groceries in Cities using Electric Vehicle

Narayanasamy, Harivignesh January 2022 (has links)
With the increase in the growth of the e-commerce sector since the past decade, the pressure has been progressively more applied to the operations and supply chain. As the pandemic has pushed the companies to provide services at the customer doorstep due to the difficulties in accessing services from brick-and-mortar stores, the logistical operation of the companies is continuously put under pressure. Though the performance aspect of the supply chain operations is achieved as per company’s objectives, the sustainability part is always overlooked. For any logistics provider, the last mile is considered as one of the main deterrents in their supply chain operations. Some of the main factors include performance of the distribution process, delivery time window, level of service, congestion in the urban area, etc. The above and some other factors make it extremely difficult for the logistics provider to be sustainable in their operations.  There is a growing interest among the logistics provider to use electric vehicles in urban logistics. In particular, light electric vehicles are considered to be a valid alternate for fossil fuel powered sprinters or vans. The purpose of the study is to identify the logistical, technological and infrastructural challenges associated with implementing electric vehicles with refrigeration system in delivering e-groceries in cities. The thesis follows the methodology of collecting data from developed electric vehicle and analysing the data to identify the feasibility of implementing electromobility in last mile delivery. In order to identify the commercial application of electromobility, the collected data is applied in the developed simulation model. The scenario-based analysis has been used in the data collection and in simulation modelling experimentation. The scenario analysis has been used to have an in-depth understanding of all the possible outcomes. The results from the test observations provided data for further studies while the results from simulation modeling presented evidence for the effective application of electric vehicles in delivering e-groceries in last-mile. The comparison of electric vehicle (EV) with fossil fuel powered vehicle provided the strong performance of EV’s in terms of environmental, operational, and socio-economic aspects. The thesis provides new knowledge in the area of electromobility in last-mile research and also proposes potential future work which will be assisting the forthcoming research in advancing the boundary of the research topic. / Med den ökade tillväxten inom e-handelssektorn sedan det senaste decenniet har trycket successivt applicerats mer på verksamheten och leveranskedjan. Eftersom pandemin har drivit företagen att tillhandahålla tjänster utanför kunddörren på grund av svårigheterna att få tillgång till tjänster från tegelbutiker, sätts företagens logistiska drift kontinuerligt under press. Även om prestandaaspekten av leveranskedjans verksamhet uppnås enligt företagetsmål, förbises alltid hållbarhetsdelen. För alla logistikleverantörer betraktas den sista milen som en av de främsta avskräckningarna i deras leveranskedja. Några av huvudfaktorerna inkluderar distributionsprocessens prestanda, leveranstidsfönster, servicenivå, trängsel i tätorten etc. Ovanstående och några andra faktorer gör det extremt svårt för logistikleverantören att vara hållbar i sin verksamhet.  Det finns ett växande intresse bland logistikleverantören att använda elfordon i stadslogistik. I synnerhet anses lätta elfordon vara ett giltigt alternativ för sprinter eller skåpbilar som drivs med fossila bränslen. Syftet med studien är att identifiera de logistiska, tekniska och infrastrukturella utmaningarna i samband med att implementera elfordon med kylsystem för att leverera e-livsmedel i städer. Avhandlingen följer metodiken för att samla in data från utvecklade elfordon och analysera data för att identifiera genomförbarheten av att implementera elektromobilitet i sista mils leverans. För att identifiera den kommersiella tillämpningen av elektromobilitet, tillämpas den insamlade informationen i den utvecklade simuleringsmodellen. Den scenariobaserade analysen har använts i datainsamlingen och i simuleringsmodellexperiment. Scenarioanalysen har använts för att få en fördjupad förståelse av alla möjliga utfall. Resultaten från testobservationerna gav data för ytterligare studier medan resultaten från simuleringsmodellering presenterade bevis för den effektiva tillämpningen av elfordon för att leverera e-livsmedel på sista milen. Jämförelsen av elfordon (EV) med fossilbränsledrivna fordon gav elbilarnas starka prestanda när det gäller miljömässiga, driftsmässiga och socioekonomiska aspekter. Avhandlingen ger ny kunskap inom området elektromobilitet inom forskning på sista milen och föreslår även potentiellt framtida arbete som kommer att hjälpa den kommande forskningen att flytta fram gränsen förforskningsämnet.

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