Dissertations / Theses on the topic 'Modelling and simulation in information systems'
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Eatock, Julie. "Dynamic integrated modelling of information systems and business process simulation." Thesis, Brunel University, 2003. http://bura.brunel.ac.uk/handle/2438/5248.
Full textSerrano, Rico Alan Edwin. "Stochastic Information Technology Modelling for Business Processes." Thesis, Brunel University, 2002. http://bura.brunel.ac.uk/handle/2438/2035.
Full textDi, Domenica Nico. "Stochastic programming and scenario generation : decision modelling simulation and information systems perspective." Thesis, Brunel University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415936.
Full textWang, Qian. "Modelling and simulation of integrated operational and information processing systems in manufacturing." Thesis, University of Sussex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394898.
Full textHultberg, Ida. "Modelling and Simulation of Unknown Factors in Simulation Based Acquisition." Thesis, University of Skövde, Department of Computer Science, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-715.
Full textWhen a new product should be acquired, a model over its functionality is made. A quite new idea in the military area is to use simulations to find out what and how much to acquire. Since the product never has been on the market before it is hard to know how factors in the surroundings, like weather and other active objects, will affect it. Therefore these unknown factors that appear during the creation or acquiring of a new product need to be taken into consideration.
A literature study is performed about how modelling of simulations can be done, and how unknown factors can be considered when modelling a simulation. The study goes into if unknown factors are taken into consideration when modelling in the Process component in Simulation Based Acquisition (SBA). The result of this study shows that SBA facilitates in the process of finding and reducing unknown factors.
Ghaffari, Abdolali. "Application of geographical information systems (GIS) and crop simulation modelling in sustainable agriculture." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312108.
Full textUlriksson, Jenny. "Consistency management in collaborative modelling and simulation." Licentiate thesis, KTH, Microelectronics and Information Technology, IMIT, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-571.
Full textThe aim of this thesis is to exploit the technological capabilities of computer supported collaborative work (CSCW) in the field of collaborative Modelling and Simulation (M&S). The thesis focuses on addressing two main problems: (i) providing flexible means of consistency management in collaborative M&S, and (ii) the ability of providing platform and application independent services for collaborative M&S.
In this work, some CSCW technologies and how some of the concepts can be incorporated in a distributed collaborative M&S environment, have been studied. An environment for component based simulation development and visualization, which provides support for collaborative M&S, has been designed. Some consistency policies that can be used in conjunction with distributed simulation and the High Level Architecture (HLA) have been investigated. Furthermore, the efficient utilization of HLA and XML in combination, as the foundation of a CSCW infrastructure has been proved. Two consistency policies were implemented utilizing HLA, a strict and an optimistic, in the distributed collaborative environment. Their performance was compared to the performance of a totally relaxed policy, in various collaboration situations.
Aramrattana, Maytheewat. "Modelling and Simulation for Evaluation of Cooperative Intelligent Transport System Functions." Licentiate thesis, Högskolan i Halmstad, Centrum för forskning om inbyggda system (CERES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:vti:diva-12683.
Full textKessels, Henricus. "Wildfire Management in the Southside Region of Canada’s Montane Cordillera - A Systems Modelling Application on Firebreak Strategies." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35107.
Full textGustafsson, Magnus. "Evaluation of StochSD for Epidemic Modelling, Simulation and Stochastic Analysis." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-426227.
Full textKomashie, Alexander. "Information-theoretic and stochastic methods for managing the quality of service and satisfaction in healthcare systems." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4402.
Full textTavakoli, Siamak. "A generic predictive information system for resource planning and optimisation." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/8116.
Full textLol, Wilford Gibson. "An investigation of the impact of routing protocols on MANETs using simulation modelling a dissertation submitted to Auckland University of Technology in partial fufilment of the requirements for the degree of Master of Computer and Information Sciences, 2008 /." Click here to access this resource online, 2008. http://hdl.handle.net/10292/718.
Full textIncludes bibliographical references. Also held in print ( xi, 105 leaves : ill. ; 30 cm.) in the Archive at the City Campus (T 621.382 LOL)
SOUZA, RAMON DE ATTAYDE BARROS DE. "EVALUATION OF PRESENCE OF HEBICIDE PARAQUAT IN RUNNOF IN WATERSHED BOM JARDIM WITH MODELLING AND SIMULATION WITH SIG (GEOGRAPHICAL INFORMATION SYSTEM)." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=15130@1.
Full textEsta tese propõe avaliar a presença do herbicida paraquat no escoamento superficial, ocorrido na microbacia do Córrego Pito Aceso, localizada em Bom Jardim-RJ, utilizando inicialmente uma etapa de modelagem e, posteriormente, uma etapa de simulação com SIG (Sistema de Informação Geográfica). A etapa da modelagem foi desenvolvida especificamente para cinco parcelas padrão Wischmeier, considerando suas respectivas culturas, manejo, tipo de solo e os seguintes parâmetros de influência no escoamento: interceptação do pesticida pela cultura, sorção do pesticida no solo. O fator de declividade da bacia hidrográfica foi considerado apenas para a etapa de simulação com SIG. Os resultados foram representados através de índices e concentrações de paraquat presente no escoamento e, posteriormente validados, através de dados reais medidos na área de estudo, e analisados pela EMBRAPA SOLOS. Uma vez validados, os resultados das parcelas foram georeferenciados em mapas poligonais e matriciais, através do software Arcgis 9.2, dando início, assim, a etapa de simulação dos resultados para toda a bacia hidrográfica. Pretende-se, ao final, avaliar o grau de influencia de alguns parâmetros considerados, tais como: interceptação do paraquat pela cultura e declividade da bacia hidrográfica. Os resultados das concentrações do paraquat (presente no escoamento) poderão em trabalhos futuros, serem comparados com os padrões mínimos aceitáveis para segurança ambiental, objetivando estabelecer limites de uso do paraquat em bacias hidrografias similares. Espera-se também, o desenvolvimento e aplicação da mesma modelagem utilizada nessa tese, para outros tipos de pesticidas aplicados e em diferentes bacias hidrográficas.
This study proposes to evaluate the presence of the herbicide paraquat in runoff water in a catchment in the municipality of Bom Jardim – RJ, using two steps: modelling and simulation with GIS (Geographical Information System). The step of modelling was developed specifically for five standarded Wischmeier scenarios, considering the respective crops, management, soil type and the following parameters: culture interception and soil of the sorption. The slope was considered only for the simulation steps of the GIS. The results were represented as rates paraquat concentrations in runoff and afterwards validated with real data measured in the study area and analysed by EMBRAPA SOLOS. After validation, the scenario results was georeferenced as raster images using the Arcgis Software 9.2, beginning the result simulation step for the watershed. The aim is also to evaluate the influence of some parameters: paraquat interception by the crop and slop of the catchmente. The results of paraquat concentrations in the runoff can, in the future , be compared with accepted standards for environmental safety, defining thereshobes limits of paraquat use in similar watersheds. We also expect the development and application of the same modeling approach used in this study for other types of pesticides and in different watersheds.
Eugénio, António Luís Beja. "The information systems and technology innovation process: a study using an agent-based approach." Master's thesis, Instituto Superior de Economia e Gestão, 2007. http://hdl.handle.net/10400.5/636.
Full textUm modelo abstracto baseado em agentes é utilizado para estudar a inovação em Sistemas de Informação e em Tecnologia de Informação, no plano organizacional, utilizando uma aproximação sócio-cognitiva. A conclusão do estudo indica que o poder dos profissionais conhecedores de tecnologias de informação na decisão de adopção de uma determinada inovação varia com o nível de concordância de ideias entre eles e os decisores, ao mesmo tempo que depende da taxa de depreciação das transacções, conduzindo a uma forte flutuação de poder quando o ambiente é instável.
An abstract Agent Based Model is used to study Information Systems and Information Technology innovation on an organizational realm, using a socio-cognitive approach. Conclusion is drawn that the power of the knowledge workers in the decision to adopt an IS/IT innovation within an organization varies with the matching level of ideas between them and the top management, while being dependant of the transactions’ depreciation rate, leading to a strong fluctuation of power when the environment is unstable.
Frykskog, David, and Hjalmar Jonsson. "Construction of RF-link budget template for transceiver modelling." Thesis, Linköpings universitet, Fysik och elektroteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-162159.
Full textTabibzadeh, Sam, and Adrian Moradi. "Modellering av ett rapportgenereringssystem ur ett designperspektiv." Thesis, Uppsala universitet, Institutionen för informatik och media, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-324968.
Full textWriting reports is very important in many functions of society and is mostly done manually today. To be able to automate the generation of reports has for a long time been a challenge, and a solution would save time and resources. The question of how an infrastructure of an automated report generator could be designed is very relevant for both research and practice. The Swedish Armed Forces is no exception, currently they write reports manually when they use their simulation system for fictional battles which they later on use for training of personnel. We have cooperated with the Swedish Defence Research Agency (FOI) to study this question. In this study, we present an information infrastructure model. The model is based upon a design perspective and concerns an information infrastructure that supports a simulation system. The model takes into account both practical and research related perspectives. With the help of requirements that were gathered via interviews and discussions with FOI, Swedish Armed Forces and an expert within the field of information infrastructure, we took into account practical related aspects in the development of the model. The research related aspects are taken into account by using other studies and methods.
Denizot, Audrey. "Simulation de la signalisation calcique dans les prolongements fins astrocytaires." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI093/document.
Full textAstrocytes are predominant glial cells in the central nervous system, which are essential for the formation of synapses, participate to the blood-brain barrier and maintain the metabolic, ionic and neurotransmitter homeostasis. Recently, astrocytes have emerged as key elements of information processing in the central nervous system. Astrocytes can contact neurons at synapses and modulate neuronal communication via the release of gliotransmitters and the uptake of neurotransmitters. The use of super-resolution microscopy and highly sensitive genetically encoded Ca2+ indicators (GECIs) has revealed a striking spatiotemporal diversity of Ca2+ signals in astrocytes. Most astrocytic signals occur in processes, which are the sites of neuron-astrocyte communication. Those processes are too fine to be resolved by conventional light microscopy so that super-resolution microscopy and computational modeling remain the only methodologies to study those compartments. The work presented in this thesis aims at investigating the effect of spatial properties (as e.g cellular geometry, molecular distributions and diffusion) on Ca2+ signals in those processes, which are deemed essential in such small volumes. Historically, Ca2+ signals were modeled with deterministic well-mixed approaches, which enabled the study of Ca2+ signals in astrocytic networks or whole-cell events. Those methods however ignore the stochasticity inherent to molecular interactions as well as diffusion effects, which both play important roles in small volumes. In this thesis, we present the spatially-extended stochastic model that we have developed in order to investigate Ca2+ signals in fine astrocytic processes. This work was performed in collaboration with experimentalists that performed electron as well as super-resolution microscopy. The model was validated against experimental data. Simulations of the model suggest that (1) molecular diffusion, strongly influenced by the concentration and kinetics of endogenous and exogenous buffers, (2) intracellular spatial organization of molecules, notably the co-clustering of Ca2+ channels, (3) ER geometry and localization within the cell, (4) cellular geometry strongly influence Ca2+ dynamics and can be responsible for the striking diversity of astrocytic Ca2+ signals. This work contributes to a better understanding of astrocyte Ca2+ signals, a prerequisite for understanding neuron-astrocyte communication and its influence on brain function
Rossetti, Rosaldo Jose Fernandes. "A BDI-based approach for the assessment of driver's decision-making in commuter scenarios." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2002. http://hdl.handle.net/10183/5595.
Full textThe rapid growth of urban areas has a significant impact on traffic and transportation systems. New management policies and planning strategies are clearly necessary to cope with the more than ever limited capacity of existing road networks. The concept of Intelligent Transportation System (ITS) arises in this scenario; rather than attempting to increase road capacity by means of physical modifications to the infrastructure, the premise of ITS relies on the use of advanced communication and computer technologies to handle today’s traffic and transportation facilities. Influencing users’ behaviour patterns is a challenge that has stimulated much research in the ITS field, where human factors start gaining great importance to modelling, simulating, and assessing such an innovative approach. This work is aimed at using Multi-agent Systems (MAS) to represent the traffic and transportation systems in the light of the new performance measures brought about by ITS technologies. Agent features have good potentialities to represent those components of a system that are geographically and functionally distributed, such as most components in traffic and transportation. A BDI (beliefs, desires, and intentions) architecture is presented as an alternative to traditional models used to represent the driver behaviour within microscopic simulation allowing for an explicit representation of users’ mental states. Basic concepts of ITS and MAS are presented, as well as some application examples related to the subject. This has motivated the extension of an existing microscopic simulation framework to incorporate MAS features to enhance the representation of drivers. This way demand is generated from a population of agents as the result of their decisions on route and departure time, on a daily basis. The extended simulation model that now supports the interaction of BDI driver agents was effectively implemented, and different experiments were performed to test this approach in commuter scenarios. MAS provides a process-driven approach that fosters the easy construction of modular, robust, and scalable models, characteristics that lack in former result-driven approaches. Its abstraction premises allow for a closer association between the model and its practical implementation. Uncertainty and variability are addressed in a straightforward manner, as an easier representation of humanlike behaviours within the driver structure is provided by cognitive architectures, such as the BDI approach used in this work. This way MAS extends microscopic simulation of traffic to better address the complexity inherent in ITS technologies.
Abideen, Amar. "Dielectric Response and Partial Discharge Characteristics of Stator Winding Insulation System with SiC Stress Grading." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-284502.
Full textDen typiska konstruktionen av en statorhärva använder ändglimmskydd (ECP), somär tillverkad av halvledande material som kiselkarbid (SiC). Syftet med ECP är attjämna ut det elektriska fältet vidövergången från spåret tilländlindningen, för attundvika högpåkänning och partiell urladdningsaktivitet (PD). Arbetet som presenteras här undersöker hur ECP påverkar den dielektriska responsen hos en statorspole, vid tidsdomänoch frekvensdomänmätningar vid höga spänningar. Den studerar också hur väl tidsdomänresultat som omvandlas till frekvensdomänen motsvarar direkta mätningar. Som en annan punkt visades ECP:s inverkan på PD-aktivitet. Mätningar av dielektrisk respons och PD gjordes på nya statorhärvor som tillverkades för en stor motor. Resultaten visar att tillämpningen av ECP-konstruktionen avsevärt minskar PD-aktiviteten och ökar inceptionsspänningen. Dessutom har spolens dielektriska respons med ECP-tejp visat sig ha en ickelinjär spänningsberoende egenskap på grund av närvaron av ECP. Ö kad spänning orsakar en förskjutning av förlusttoppen mot högre frekvens. En modell för ECP användeseteendet, och dess resultat jämförs med mätningarna.utligen presenteras FEM-simulering som visar hur ECP gör fältet jämnare.
Kunštátský, Martin. "Sebeorganizace v rozsáhlých distribuovaných systémech." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236530.
Full textJohansson, Jenny, and Mikaela Waller. "Control Oriented Modeling of the Dynamics in a Catalytic Converter." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4154.
Full textAvgasmängden som bensindrivna fordon tillåts släppa ut minskas hela tiden. Ett sätt att möta framtida krav, är att förbättra katalysatorns effektivitet. För att göra detta kan luft-bränsle-förhållandet regleras med avseende på syrelagringen i katalysatorn, istället för som idag, reglera mot stökiometriskt blandningsförhållande. Eftersom syrelagringen inte går att mäta med en givare behövs en modell som beskriver katalysatorns dynamiska egenskaper. Tre sådana modeller har undersökts, utvärderats och jämförts.
Två av modellerna har implementerats i Matlab/Simulink och anpassats till mätningar från en experimentuppställning. För att kunna observera syrelagringen online valdes slutligen en av modellerna ut, och implementerades i ett Extended Kalman filter.
Ytterligare arbete behöver läggas ner på den mest lovande modellen, och detsamma gäller för Kalmanfiltret, men på sikt förväntas resultaten kunna bli bra.
The legal amount of emissions that vehicles with spark ignited engines are allowed to produce are steadily reduced over time. To meet future emission requirements it is desirable to make the catalytic converter work in a more efficient way. One way to do this is to control the air-fuel-ratio according to the oxygen storage level in the converter, instead of, as is done today, always trying to keep it close to stoichiometric. The oxygen storage level cannot be measured by a sensor. Hence, a model describing the dynamic behaviors of the converter is needed to observe this level. Three such models have been examined, validated, and compared.
Two of these models have been implemented in Matlab/Simulink and adapted to measurements from an experimental setup. Finally, one of the models was chosen to be incorporated in an extended Kalman filter (EKF), in order to make it possible to observe the oxygen storage level online.
The model that shows best potential needs further work, and the EKF is working with flaws, but overall the results are promising.
Oezkan, Oezguer. "Operational modelling practical manufacturing systems." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323768.
Full textPetrounias, Ilias. "Conceptual modelling for temporal information systems." Thesis, University of Manchester, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488408.
Full textCordeiro, José A. M. "Normative approach to information systems modelling." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553135.
Full textAlbertyn, Martin. "Generic simulation modelling of stochastic continuous systems." Thesis, Pretoria : [s.n.], 2004. http://upetd.up.ac.za/thesis/available/etd-05242005-112442.
Full textKraus, Vladimír. "Modelling and Simulation of Pull Production Systems." Master's thesis, Vysoká škola ekonomická v Praze, 2006. http://www.nusl.cz/ntk/nusl-8579.
Full textChi, Sungdo. "Modelling and simulation for high-autonomy systems." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185650.
Full textMizeranschi, Alexandru E. "Multiscale modelling and simulation in systems biology." Thesis, Ulster University, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.737992.
Full textTomlinson, S. P. "The hydraulic automatic simulation package (HASP) : Modelling and simulation aspects." Thesis, University of Bath, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375337.
Full textTsalgatidou, Aphrodite. "Dynamics of information systems : modelling and verification." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257152.
Full textCutts, Geoff. "Modelling and analysis of parallel information systems." Thesis, Sheffield Hallam University, 1993. http://shura.shu.ac.uk/19524/.
Full textSolgård, Stian Bu. "Modelling, simulation and control of macro economic systems." Thesis, Norwegian University of Science and Technology, Department of Engineering Cybernetics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9023.
Full textToday's Basel-type banking system is compared with a 100% reserve banking system. Furthermore, negative interest rate on deposits is introduced for these two systems thus two new models are introduced. Eventually all four models are compared with each other in terms of debt crisis mechanisms and if they are prone to enter a liquidity trap. The comparing is done for debt to GDP ratio around a certain ratio of 60% thought to give neutral confidence, thus the effect from confidence dynamics can be excluded for these simulations.
Shoaki, Salman Daif-Allah. "Generic robotic manufacturing systems : modelling/simulation and control." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390617.
Full textGow, John A. "Modelling, simulation and control of photovoltaic converter systems." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/6871.
Full textLavery, Eamonn. "Object oriented modelling and simulation of manufacturing systems." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361254.
Full textHayat, Tariq. "Modelling, simulation and control of mine ventilation systems." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387494.
Full textSaghafi, Arash. "Ontological and cognitive principles on information systems modelling." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59427.
Full textBusiness, Sauder School of
Graduate
Fragos, Serafeim. "Behavioural modelling in management and accounting information systems." Thesis, Lancaster University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.483621.
Full textSaad, Nordin. "Modelling, simulation, and analysis of supply chain systems using discrete-event simulation." Thesis, University of Sheffield, 2003. http://etheses.whiterose.ac.uk/14771/.
Full textGeitner, Gert-Helge, and Guven Komurgoz. "Power Flow Modelling of Dynamic Systems." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-171305.
Full textAhmadi, Achachlouei Mohammad. "Exploring the Effects of ICT on Environmental Sustainability: From Life Cycle Assessment to Complex Systems Modeling." Doctoral thesis, KTH, Miljöstrategisk analys (fms), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171443.
Full textDen ökande produktionen och konsumtionen av produkter och tjänster inom informations- och kommunikationsteknik (IKT) leder till en ökning av den globala elanvändningen samt direkta miljökonsekvenser kopplade till IKT. Men IKT har även indirekta miljömässiga effekter. Dessa kan vara positiva till exempel genom substitutions- och optimeringseffekter eller negativa genom att till exempel ge upphov till ytterligare efterfrågan på grund av effektivisering (så kallade reboundeffekter). Olika metoder kan användas för att modellera och bedöma både direkta och indirekta effekter av IKT. Syftet med denna avhandling är att undersöka metoder för modellering samt att studera miljöeffekter av IKT och elektronisk media med hjälp av livscykelanalys (LCA) och även modellering av komplexa och dynamiska system, samt simuleringsteknik, så som System Dynamics (SD) och agentbaserad (AB) modellering. Avhandlingen omfattar fem artiklar (artikel I-V). Artikel I & II beskriver resultaten från en fallstudie där miljöeffekter kopplade till en svensk tidskrift studeras med LCA. Tidskriftens version för surfplatta samt motsvarande tryckta version studeras och jämförs. Artikel III går ett steg vidare från produktnivåns LCA. Artikeln återkopplar till en SD simuleringsstudie som ursprungligen genomfördes under 2002. Simuleringsstudien gällde framtida miljöeffekter av IKT i 15 europeiska länder med tidspespektivet 2000-2020. I artikeln valideras tre scenarier från simuleringsstudien med hjälp av nya empiriska data från 2000-2012 och ett nytt scenario modelleras. Kvantitativa och kvalitativa resultat från den ursprungliga studien diskuteras. Till exempel visar artikel III att IKT har en stimulerande effekt på den totala persontrafiken genom att göra den mer kostnads- och tidseffektiv (reboundeffekt). Modelleringsmekanismen som används för att representera denna reboundeffekt diskuteras vidare i artikel IV. Artikeln belyser och diskuterar den återkopplingsslinga (feedback-loop) som används för att modellera två typer av reboundeffekter kopplade till persontrafik (direkt ekonomisk rebound och tidsrelaterad rebound) samt jämför med en tidigare studie. Artikel IV behandlar också den roll systemtänkande och modellering kan spela i konceptualisering och kommunikation av reboundeffekters dynamik. För att ytterligare undersöka systemmodelleringens och simuleringens möjligheter att representera icke-linjära komplexa och dynamiska system (exempel på sådana diskuteras i artikel III och IV), sammanställer artikel V tidigare studier som jämför SD och AB-metoder och -modeller. Studiernas mål och metod summeras och resultaten med avseende på vilka kriterier som presenteras för att välja mellan SD och AB sammanställs. Även processen för att omvandla en befintlig SD-modell till en AB-modell beskrivs. Avhandlingens slutsats är att LCA och systemmodelleringsmetoder kan vara användbara för att studera IKTs direkta effekter så väl som indirekta effekter på miljön.
QC 20150813
Posse, Ernesto. "Modelling and simulation of dynamic-structure discrete-event systems." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22006.
Full textLa modélisation et la simulation à événements discrets constituent une approche bien établie pour la description et l'étude des systèmes dynamiques complexes. Ces dernières années, il y a eu un regain d'intérêt pour la modélisation des systèmes complexes à structure dynamique. Ces systèmes sont généralement plus difficiles à comprendre et à analyser que les systèmes ayant une structure statique. Cette analyse et cette compréhension peuvent être développées à l'aide de formalismes de modélisation fondés sur une base solide et des outils appropriés. Dans cette thèse, nous explorons une approche de modélisation et de simulation des systèmes à événements discrets fondée sur l'algèbre de processus. Ce document se compose de deux parties. Dans la première partie, nous étudions ce que l'on appelle le formalisme Discrete-EVent System Specifications (DEVS.) Nous développons un autre fondement théorique pour DEVS fondée sur la sémantique opérationnelle structurelle, en mettant l'accent sur les propriétés de déterminisme et de compositionalité. Dans la deuxième partie, nous développons un langage de modélisation pour systèmes à structure dynamique nommé kiltera, en nous fondant sur les algèbres de processus et en incorporant des éléments de modélisation à événements discrets. Ce langage, en se fondant sur le \pi-calcul, nous permet de décrire et de raisonner sur les systèmes mobiles, distribués et au temps-réel, à événements discrets, dans un cadre conceptuel unique. Nous développons une base théorique fondée sur la sémantique opérationnelle structurelle et nous établissons des propriétés fondamentales concernant le déterminisme-temps, la continuité, la compositionalité et la légitimité. Nous construisons un simulateur pour le langage qui supporte à la fois l'exécution séquentielle et distribuée de modèles, en utilisant une variante de l'algorithme Time Warp. Enfin, nous appliquons ce la
Sheikholeslami, Majid. "Modelling and simulation environment for force-feedback multibody systems." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103737.
Full textNous d'ecrivons ici un environnement de simulation développé pour les dispositifs de retour d'effort. Cet environnement est basé sur le Multibody Toolbox (MuT) mis au point par l'Agence spatiale canadienne, qui a la capacité de manipulation symbolique en utilisant Maple et Matlab/Simulink afin de traiter de l'interface numérique. L'environnement de simulation sert un double objets: (1) la modélisation, l'analyse dynamique et la visualisation de systèmes multicorps pour aider à la conception des dispositifs de retour d'effort, (2) la génération de modèles de systèmes dynamiques afin de servir des environnements virtuels avec lesquels un appareil physique de retour d'effort tente d'avoir interaction. Le deuxième objectif implique également l'intégration du logiciel en question avec celui pour la commande en temps réel Quanser QuaRC afin de contrôler le dispositif de retour d'effort. Ce travail porte en particulier sur la classe de dispositifs qui emploient le paradigme de commande par impédance. Les dispositifs de retour d'effort et les modèles d'environnement virtuel emploient souvent des topologies des systèmes mécaniques qui peuvent être représentées par chaînes d'éléments multicorps couplés en boucle fermée. Pour tous les deux principaux objectifs ci-dessus, l'examen des contraintes cinématiques explicitement données dans la dynamique et le contrôle des modèles sous-jacents des systèmes multicorps a une importance primordiale. Le cadre de simulation est capable d'utiliser des techniques efficaces de stabilisation afin de fournir la performance ciblée tout en étant également capable de gérer des systèmes non-conservateurs qui gagnent de l'énergie au cours de la simulation, comme si l'algorithme de contrôle injectait de l'énergie dans le système. La simulation des systèmes contraints a reçu une attention considérable durant les dernières années. Cependant, les problèmes issus d'une interprétation plus large de problème de mouvement constraint ne sont pas vraiment pris en considération. Une telle interprétation représente par la connection d'un logiciel de simulation dynamique à un dispositif faisant partie du matériel. C'est le cas de dévirage haptique basé sur des mécanismes de retour d'effort. Ces aspects seront illustrés par des simulations et un banc d'essai expérimental.
MacQueen, John. "The modelling and simulation of energy management control systems." Thesis, University of Strathclyde, 1997. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21355.
Full textGely, Laurent. "Modélisation et optimisation de la gestion opérationnelle du trafic ferroviaire en cas d’aléas." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14177.
Full textOn-line re-scheduling of trains aims to find accurate solutions after an incident has occurred on the railway network. When we consider a large area, solutions consist in calculating new timetables, sequences and routes of trains. This problem asks for decision support tools based on operational research techniques.This thesis aims to develop solutions toward an operational tool, it articulates around three main parts. The first part defines an exhaustive model of the railway system operations and a multiscalable description of the infrastructure.The second part presents three mathematical models of the rescheduling problem associated with this description. We preset a exhaustive continuous time based model including headways that take into account speeds of trains, plus a discrete time based model and an hybrid model combining both formulations.The last part describes first implementations and the global framework we need to develop in order to solve the real world problem. It emphases on expected synergies, specilaly between simulation and optimization techniques
Balaji, Kamalakkannan Balaji. "Modelling and Simulation of Vehicle Kinematics and Dynamics." Thesis, Högskolan i Halmstad, Halmstad Embedded and Intelligent Systems Research (EIS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34363.
Full textTran, Xuan-Thien Mechanical & Manufacturing Engineering Faculty of Engineering UNSW. "Modelling and simulation of electronically controlled diesel injectors." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2003. http://handle.unsw.edu.au/1959.4/19278.
Full textMerrett, Geoff V. "Energy- and information-managed wireless sensor networks : modelling and simulation." Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/65002/.
Full textKoutsoukis, Nikitas-Spiros. "Decision modelling and information systems : the interaction of information and decision technologies." Thesis, Brunel University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263519.
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