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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.
41

Exit game? Any unsaved progress will be lost : En praktikteoretisk analys av relationen mellan svenska spelföretag och ABM-institutioner / Exit game? Any unsaved progress will be lost : A practice theory analysis of the relationship between Swedish game companies and ALM-institutions.

Risheim, Lina, Smedsaas, Klara January 2017 (has links)
This thesis analyzes the relationship between Swedish video game companies and the institutions for Archive, Libraries and Museums (ALM). The aim is to further the discussion regarding preservation of digital games. The thesis is based on semi-structured interviews with four video game companies and three institutions; an archive, a library and a museum. The theoretical foundation resides within practice theory, with the assumption that a practice is a combination of what people do and what they say. By analyzing what video game companies say they do the authors ascertain which methods of preservation is currently. The analysis is a cross-examination of the seven interviews with the result indicating that while video game companies are interested in the preservation of digital games they do not participate actively in the discussion on the best method of doing so. Communica- tion between video game companies and ALM institutions has room for improvement, as it is virtually non- existent. Furthermore, the findings indicate different motivations for preserving games and it is unclear which perspective the preservation should have; a technical perspective, cultural perspective or for the company’s bene- fit. In conclusion the current situation is that ALM institutions preserve games with a cultural and/or a technical perspective while game companies preserve their games for the company’s benefit.
42

Incorporating human behaviour in an agent based model of technology adoption in the transition to a smart grid

Snape, Joseph Richard January 2015 (has links)
The requirement for affordable, secure and sustainable energy production is a pressing global challenge and the production of electricity with low carbon emissions is crucial. This usually entails large quantities of renewable energy generation, which is intermittent and often highly distributed throughout the electricity supply system. One of the proposed schemes to manage such generation is the smart grid, the transition to which forms the context for this research. The aim is to investigate the effect of certain psychological and social influences on the adoption of technology necessary to enable smart grids, in order to understand the implications for effective energy policy. In particular, the case of photovoltaic (PV) system adoption in the UK is studied. Empirical data detailing PV installations registered for the Feed in Tariff is analysed in order to understand rates of adoption and how they vary across both time and space. This analysis is combined with a review of policy intervention and literature from psychology to understand drivers for adoption among householders. The results from this study are then used to inform the design of an Agent Based Model of technology adoption within the smart grid context. The decision making of householders is modelled using an algorithm based on Social Cognitive Theory. The model is used to simulate different conditions and generate adoption scenarios in order to understand the potential effects of different parameters on adoption rates. In order to combine the analysis resulting from these methods, the multi-level perspective on transition in socio-technical systems is used to understand how a transition to a smart grid could be described and how adoption of PV in the UK under the Feed in Tariff incentive fits into such a transition. The results show that whilst economic incentive policies have had success in some areas adoption is also dependent on many non-financial parameters. Simulations show that the observability of adoption and the perceived inconvenience or urgency of adoption can have dramatic effects on rates of adoption, in some cases outweighing the rational economic effects of financial incentives. The implication for smart grid related policy is that non-financial factors should be taken into account as well as the more typical financial considerations in efforts to encourage adoption of necessary enabling technology by householders. The models developed could be used in further work to examine in detail adoption of other technologies such as smart home energy management systems and the interaction between adoption rates of multiple smart technologies.
43

Analyse et modélisation multi-agents de transports flexibles : Comparaison de services français et sénégalais / Analysis and multi-agent simulation of flexible transports : Comparison between french and senegalese services

Lammoglia, Adrien 14 October 2013 (has links)
Organiser le secteur du transport pour offrir des solutions de déplacement efficaces est aujourd'hui un enjeu capital pour nos sociétés. La flexibilité, tendant à augmenter la qualité de service, constitue un des leviers pour améliorer les transports. Diverses formes de flexibilité apparaissent en effet dans l'offre actuelle. Dans cette thèse, nous appréhendons plus particulièrement des services opérant dans deux contextes sociétaux distincts :• d'une part, dans un pays industrialisé (la France) où le recours aux transports publics reste minoritaire car la dépendance à l'automobile est toujours très forte ;• d'autre part, dans un pays en voie de développement (le Sénégal) possédant des moyens financiers limités, mais où l'usage des transports collectifs est généralisé, impliquant une grande diversité des modes et une atomisation de l'offre.Nous proposons ainsi d'analyser et de comparer le fonctionnement des transports informels et artisanaux sénégalais (tels que les taxis collectifs) avec celui des systèmes considérés comme plus modernes en France, pour lesquels les capacités d'auto-organisation des individus ont été progressivement remplacées par des systèmes d’information et de communication de haut niveau technologique et logistique. Ces innovations semblent apporter plus d'immédiateté au transport flexible, mais nécessitent en contrepartie un encadrement fort de la part des autorités publiques générant des contraintes réglementaires et spatiales. À l'opposé, les services spontanés et dérégulés qui sont proposés au Sénégal bénéficient d'une plus grande souplesse, au détriment de la sécurité des passagers.L'objectif de la thèse est d'analyser ces services, les modéliser et les simuler afin d'évaluer les apports de la flexibilité. D'un point de vue méthodologique, notre recherche est basée sur un ensemble de modèles inspirés des transports observés en France et au Sénégal, puis implémentés en Systèmes Multi-Agents (SMA) dans l'environnement Netlogo. Certains modèles sont issus d'une analyse fonctionnelle de terrain et d'autres sont plus théoriques. Par l'analyse du comportement d'agents réalisant ces services en concurrence et/ou en coopération, nous identifions d'abord des seuils et des conditions de mise en œuvre en termes d'efficacité et de couverture spatiale. En simulant les modèles sur plusieurs configurations spatiales, nous explorons ensuite leur fonctionnement et nous analysons les atouts et les faiblesse de chacun. Nous les simulons ensuite simultanément pour évaluer leur capacité de complémentarité. Cela nous permet in fine de confronter des systèmes de transports analogues à ceux observés dans les deux contextes sociétaux et d'établir une grille de comparaison en fonction des niveaux de flexibilité identifiés.. / Organizing and developing efficient urban transportation services is a key issues for actual society. The flexibility appear as an important criteria to improve the services quality and to offer attractive transportation solutions. Different forms and levels of flexibility exist in the actual supply-side. For this research we focus on flexible transports operating in two society contexts:• in an industrial country (France) where the using rate of public transportation services islow because the automobile dependency is still high;• in a developing country (Senegal), where the financial resources are limited and theutilisation of public transports is generalized, leading to a diversity of services and anatomic supply-side. More precisely, we compare the functioning of senegalese para-transit services (as collectivetaxis) with french technological systems (as Demand Responsive Transport (DRT)). In France, auto-organization skills and collective behaviours have been replaced by the utilisation of highlevel information, communication and logistic systems. These innovations bring more immediacy and spontaneity in public transports, but it needs a strong supervision from authorities, causes regulatory ans spatial constraints of servicing. In contrast, in Senegal deregulated services benefit to more spontaneity and suppleness to the detriment of the passengers security.The objective of the thesis is to analyse, model and simulate these services to evaluate thecontributions of the flexibility. Regarding the methodology, our study is based on a group ofmodels inspired by transportation systems observed in France and Senegal and implemented inMulti-Agent Systems (MAS), in the NetLogo environnement. Some models are derived from a functional analysis and others are more theoretical. By analysing behaviours of agents performing these services in concurrency or incooperation, we highlight some thresholds and optimal conditions of coverage. Simulations invarious spatial configurations allow to explore model functioning and to analyse their strengthsand limitations. Then, we simulate models in parallel (two models by simulation) to evaluate their complementarity. We compare these combined models, all of them representing transportation services observed in two different contexts. Finally, we build a comparison matrix of clues according to the model performance and flexibility levels. To conclude, this research leads to a valuable reflection on how could be designed flexible transport services in the future.
44

EXPECTATIONS IN MACROECONOMICS: PERSPECTIVES, LABORATORY EXPERIMENTS AND AB MODELS

TETTAMANZI, MICHELE 22 December 2017 (has links)
La presente tesi studia le aspettative in macroeconomia contribuendo alla letteratura esistente sia indagando circa il meccanismo di formazione delle aspettative, sia analizzando come le aspettative a razionalità limitata influenzino la dinamica economica. Nel primo capitolo viene presentato un esperimento nel quale ai soggetti viene chiesto di predire il valore futuro dell'inflazione: a seconda del trattamento, i soggetti possono venire esposti ad un segnale, che mira a stabilizzare l'economia, che fungendo quindi da indicazione prospettica (Forward Guidance). I risultati vengono poi studiati sottolineando il meccanismo di formazione delle aspettative soprattutto in funzione della credibilità del segnale; inoltre viene studiata l'efficacia dello strumento di politica monetaria nella stabilizzazione del sistema economico: si evidenzia come un segnale informativo permetta una sensibile stabilizzazione dell'economia, prevenendo spirali deflazionistiche. Nel secondo capitolo viene sviluppato un modello ad agenti il quale incorpora un meccanismo di formazione delle aspettative a razionalità limitata, derivato da esperimenti precedenti. Inoltre, grazie ad un peculiare processo di aggregazione, viene derivato un modello analiticamente trattabile che permette di studiare il meccanismo di trasmissione di uno shock, isolando gli effetti dovuti all'eterogeneità fra gli agenti e alle aspettative: entrambi gli effetti sono considerevoli ed aiutano nello spiegare la dinamica economica. / The present dissertation analyses expectations in macroeconomics, contributing to the existing literature both studying the expectation formation process, and inquiring how economic dynamic is influenced by boundedly rational expectations. The first chapter presents a learn to forecast experiment in which subject are asked to form expectation regarding the future value of inflation: depending on the treatment, subjects might be exposed to a signal, which possibly aim at stabilizing economy, mimicking the non conventional monetary policy instrument called Delphic Forward Guidance. The collected data are studied trying to recover the underlying expectation formation process highlighting especially the role of credibility of the signal; moreover from the data emerges that informative Forward Guidance helps in stabilizing economy, drastically reducing the probability of deflationary spirals. The second chapter develops an agent-based model, encapsulating a boundedly rational expectation formation process, which had been extrapolated in previous experiments. Moreover benefiting from a specific aggregation procedure, we derive a model characterized by high analytical tractability, allowing hence to study the transmission mechanisms of a shock by insulating the effects due to the heterogeneity among agents and due to expectations: both the effects are sizable and help in understanding the dynamics of the economic system.
45

Kampen om kulturarvet : Policyimperativet i Sveriges kulturarvsdigitaliseringsdiskurs

Lewis, Cecilia January 2021 (has links)
I den här uppsatsen försöker jag med hjälp av diskursanalytiska verktyg belysa vilka bakomliggande krafter det är som driver Sveriges digitalisering av kulturarvet. Genom att analysera svenska kulturpolitiska offentliga dokument, transkriptioner av en föreläsning och ett panelsamtal, samt två debattinlägg, letade jag efter det i litteraraturen beskrivna ”policyimperativet”, som har identifierats i den norska kulturpolitiska digitaliseringskontexten. Policyimperativets uttryck identifierades, och det visar sig i huvudsak förekomma inom bibliotekssektorns diskurs, som i sin tur inspirerat arkivssektorns diskurs. Museisektorn använder sig av policyimperativet i tal och i debattsammanhang, men det förekom inte nämnvärt i sektorns offentliga dokument som ingick i analysen.  Trots att policyimperativet delvis uttrycks gemensamt av ABM-institutionerna, så möts inte arkiv, bibliotek och museum i den talade diskursen, det indikerar att de tre institutionerna inte konvergerar i den svenska digitala kontexten. / In this study I use the tools of discourse analysis to shed light on the underlying forces that drive the digitalisation of Sweden’s cultural heritage. By analysing Swedish public domain culture-political documents, transcriptions of a lecture and panel session, and two newspaper opinion articles, I search for the so-called “policy imperative” which has been identified in the context of cultural politics about Norway’s digitalisation process.  Expressions of this policy imperative were indeed found, and appeared primarily within the discourse of the library sector which in turn inspired that of the archival sector. The museum sector makes use of the policy imperative in the spoken word and in the context of debates, but it was not noticeably present in those public documents from the museum sector which were analysed here. Despite the fact that the policy imperative sees a degree of common expression by LAM-institutions they do not meet in the spoken discourse, indicating that the three disciplines are not converging in the Swedish digital context.
46

The Social Construction of Nuclear Threat: US Nuclear Disarmament Discourse, 1945 - 2014 / The Social Construction of Nuclear Threat: US Nuclear Disarmament Discourse, 1945 - 2014

Pyrihová, Marie January 2015 (has links)
Nuclear weapons remains in the security discourse of the United States for over 70 years. The threat of nuclear weapons changed its content several times since then. Our study examines how the nuclear threat was socially constructed and how different actors securitized the threat and to which purpose. Our Diploma thesis uses methodological framework of discourse analysis. We examine the political and social nuclear discourse in the U.S. along two levels of analysis: governmental level and nuclear disarmament level. The diploma thesis researches multiple governmental and societal sources in order to determine how different types of nuclear threat emerged within the discourse.
47

ADAPTIVE DECISION SUPPORT SYSTEM TO NAVIGATE THE COMPLEXITY OF POST-DISASTER DEBRIS MANAGEMENT

Jooho Kim (7818005) 05 November 2019 (has links)
<div>Disaster debris management is critical to the success of disaster recovery systems. While there are multiple disaster mitigation strategies and post-disaster debris management plans, it is hard to implement because of: (i) the uniqueness of disaster incidents and randomness of its impacts; (ii) complexity of disaster debris removal operations, policy and regulations and (iii) interdependency of multiple infrastructure networks. Also, delayed debris removal operation affects following emergency response activities. Furthermore, uncontrolled debris removal activities can result in significant environmental and public health consequences. Therefore, there is a need for a systematic approach to optimizing post-disaster debris management systems. </div><div><br></div><div>This research is aimed to understand the complexity of debris management and associated emergent dynamics through the lens of an adaptive system-of-systems (SoS). To develop the adaptive decision support system, this research (a) identifies the interdependent infrastructure network within a community and its relative importance; (b) develops real-time GIS database to integrate the data associated with critical infrastructure and geographical characteristics in the community map; (c) designs and selects a TDMS network to analyze the required number, capacity and resources, based on engineering-technical, managerial, and social-political dynamics; (d) simulate the productivity of debris-management SoS based on the real-time GIS database to gain insight into the impact of the dynamical nature of a disaster-affected area; and (e) develop a visualized interactive GIS-based platform for debris management to communicate real-time debris clearance strategies and operations among different agencies and organizations.</div><div><br></div><div>To evaluate the proposed framework and decision support system, this research conducted a case study, debris removal operation in the city of Baton Rouge, after the 2016 Louisiana flood. The results demonstrated the influence of sub-systems such as TDMS locations and capacity, road network condition, available resources, existing regulations and policies, characteristics of community on the behavior of the entire disaster debris removal management as a whole. </div><div><br></div><div>The proposed decision support system for effective disaster debris management will be beneficial for emergency agencies and disaster-prone communities to evaluate and optimize their disaster debris management system. Also, the system can be systematically integrated with other emergency response systems to maximize the efficiency of the entire disaster responses during post-disaster situations. </div><div><br></div>
48

A spatially explicit model of segregation dynamics : Comparing the Schelling and the Sakoda model

Öberg, Philip January 2023 (has links)
The scientific consensus has for long been that residential segregation is best conceived of as a multidimensional phenomenon that can exist on several geographical scales (Massey &amp; Denton, 1988; Lee et al., 2008; Reardon &amp; O’Sullivan, 2004; Reardon et al., 2008). Despite this deepened understanding of residential segregation and how to best measure it, theoretical models of segregation processes have tended to disregard the diversity of dimensions and scales of segregation. Moreover, while residential segregation is broadly defined as the spatial separation of people of different social groups (Timberlake &amp; Ignatov, 2014), the frequently used Schelling model is aspatial (Schelling, 1971). In contrast, the lesser-known Sakoda model incorporates a distance-decay effect and is thus explicitly spatial (Sakoda, 1971). The aim of this thesis was to evaluate two theoretical agent-based models of segregation processes—the Schelling- and Sakoda model—by measuring the segregation patterns they generate under different parameter settings across four dimensions and six spatial scales of segregation, ranging from the micro- to the macro-scale. Thus, providing an assessment of the capacity of these models to generate (grow) different forms of residential segregation. Results from simulation experiments showed that the popular Schelling model was limited in its capacity to generate different forms of segregation. In its standard configuration it could generate micro-segregation along two out of four dimensions: Evenness and Exposure. The spatially explicit Sakoda model was able to generate segregation patterns which varied substantially across all scales on the Evenness and Exposure dimensions. In addition, it was able to generate varied patterns of Concentration and Centralization under certain parameter settings. These findings contribute new insights to the possibilities afforded by these two models in modeling processes of residential segregation. If the goal for theoretical models is to generate segregation patterns which vary across all dimensions and scales of residential segregation, then the standard configuration of the Schelling model is not enough. This thesis suggest that the Sakoda model is a promising candidate for this purpose. In addition, this thesis shows the importance of using a comprehensive measurement framework in theoretical modeling of segregation processes.
49

The prevalence of complexity in flammable ecosystems and the application of complex systems theory to the simulation of fire spread

Katan, Jeffrey 08 1900 (has links)
Les forêts sont une ressource naturelle importante sur le plan écologique, culturel et économique, et sont confrontées à des défis croissants en raison des changements climatiques. Ces défis sont difficiles à prédire en raison de la nature complexe des interactions entre le climat et la végétation, dont une le feu. Compte tenu de l’importance des écosystèmes forestiers, des dangers potentiels des feux de forêt et de la complexité de leurs interactions, il est primordial d'acquérir une compréhension de ces systèmes à travers le prisme de la science des systèmes complexes. La science des systèmes complexes et ses techniques de modélisation associées peuvent fournir des informations sur de tels systèmes que les techniques de modélisation traditionnelles ne peuvent pas. Là où les techniques statistiques et basées sur équations cherchent à contourner la dynamique non-linéaire, auto-organisée et émergente des systèmes complexes, les approches de modélisation telles que les automates cellulaires et les modèles à base d'agents (MBA) embrassent cette complexité en cherchant à reproduire les interactions clés de ces systèmes. Bien qu'il existe de nombreux modèles de comportement du feu qui tiennent compte de la complexité, les MBA offrent un terrain d'entente entre les modèles de simulation empiriques et physiques qui peut fournir de nouvelles informations sur le comportement et la simulation du feu. Cette étude vise à améliorer notre compréhension du feu dans le contexte de la science des systèmes complexes en développant un tel MBA de propagation du feu. Le modèle utilise des données de type de carburant, de terrain et de météo pour créer l'environnement des agents. Le modèle est évalué à l'aide d’une étude de cas d'un incendie naturel qui s'est produit en 2001 dans le sud-ouest de l'Alberta, au Canada. Les résultats de cette étude confirment la valeur de la prise en compte de la complexité lors de la simulation d'incendies de forêt et démontrent l'utilité de la modélisation à base d'agents pour une telle tâche. / Forests are an ecologically, culturally, and economically important natural resource that face growing challenges due to climate change. These challenges are difficult to predict due to the complex nature of the interactions between climate and vegetation. Furthermore, fire is intrinsically linked to both climate and vegetation and is, itself, complex. Given the importance of forest ecosystems, the potential dangers of forest fires, and the complexity of their interactions, it is paramount to gain an understanding of these systems through the lens of complex systems science. Complex systems science and its attendant modeling techniques can provide insights on such systems that traditional modelling techniques cannot. Where statistical and equation-based techniques seek to work around the non-linear, self-organized, and emergent dynamics of complex systems, modelling approaches such as Cellular Automata and Agent-Based Models (ABM) embrace this complexity by seeking to reproduce the key interactions of these systems. While there exist numerous models of fire behaviour that account for complexity, ABM offers a middle ground between empirical and physical simulation models that may provide new insights into fire behaviour and simulation. This study seeks to add to our understanding of fire within the context of complex systems science by developing such an ABM of fire spread. The model uses fuel-type, terrain, and weather data to create the agent environment. The model is evaluated with a case study of a natural fire that occurred in 2001 in southwestern Alberta, Canada. Results of this study support the value of considering complexity when simulating forest fires and demonstrate the utility of ABM for such a task.
50

Ronald Reagan's Strategic Defense Initiative and transatlantic relations, 1983-86

Andreoni, Edoardo January 2017 (has links)
My doctoral project investigates the impact of Ronald Reagan’s Strategic Defense Initiative on transatlantic relations during the period 1983-86. The dissertation focuses on the three main European powers, namely Britain, France, and the Federal Republic of Germany, and examines their reaction to SDI both individually and comparatively. The study exploits SDI’s position at the intersection of nuclear strategy, political ideology, Cold War diplomacy, and industrial politics to offer a multifaceted, multi-national, and primary source-based analysis of US-European relations during the Reagan Presidency. The picture of the transatlantic relationship which emerges from the dissertation is a complex and nuanced one. On the one hand, the analysis argues that relations across the Atlantic during the Reagan era cannot be reduced to a scenario of accelerating ‘drift’ between the United States and Western Europe. Instead, on SDI as well as on other matters, moments of acute friction alternated with a constantly renewed search for dialogue, cooperation, and compromise on the part of the Europeans and also, if to a lesser degree, of the Americans. On the other hand, the ‘exceptionalist’ ideology and worldview underpinning SDI, the prevailing indifference in Washington to its implications for NATO, and most importantly the persistent anti-nuclear rhetoric and ambitions associated with the initiative revealed a distinct lack of sensitivity to European interest by the Reagan administration. As the dissertation shows, the anti-nuclear drive inherent in SDI, which both reflected and reinforced Reagan’s deep-seated interest in nuclear abolition, constituted the most disruptive aspect of the initiative from the viewpoint of European leaders. In these respects, the SDI controversy epitomises the unilateral tendencies and increasingly divergent priorities from those of the European allies which characterised much of the Reagan administration’s foreign policy – making the 1980s a decade of recurrent tensions in transatlantic relations.

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