• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 29
  • 11
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 63
  • 13
  • 13
  • 12
  • 9
  • 9
  • 8
  • 8
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 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.
51

Simulação de multidões e planejamento probabilístico para otimização dos tempos de semáforos / Crowd simulation and probabilistic planning for traffic light optimization

Coelho, Renato Schattan Pereira, 1987- 03 February 2012 (has links)
Orientadores: Siome Klein Goldenstein, Jacques Wainer / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-22T23:53:33Z (GMT). No. of bitstreams: 1 Coelho_RenatoSchattanPereira_M.pdf: 864445 bytes, checksum: 8f57902047a23925af4b81fa0d7f3188 (MD5) Previous issue date: 2013 / Resumo: O trânsito é um problema cada vez maior nas cidades, consumindo recursos e agravando a poluição; em São Paulo perdem-se cerca de R$33 bilhões por ano por causa do trânsito. Neste trabalho de mestrado desenvolvemos um sistema que une as áreas de simulação de multidões e planejamento probabilístico para otimizar semáforos de tempo fixo. Essas duas áreas apresentam algoritmos que permitem soluções eficientes para os problemas, mas a sua aplicação ainda depende largamente da intervenção de especialistas no problema a ser estudado, seja descrevendo o problema de planejamento probabilístico, seja interpretando os dados devolvidos pelo simulador. Nosso sistema diminui essa dependência ao utilizar autômatos celulares para simular o tráfego e gerar informações que são então utilizadas para descrever o problema de planejamento probabilístico. Com isso podemos: (i) reduzir a necessidade de coleta de dados, que passam a ser gerados pelo simulador e (ii) produzir bons planos para o controle de semáforos de tempo fixo sem que seja necessária a intervenção de especialistas para a análise dos dados. Nos dois testes realizados a solução proposta pelo sistema diminuiu o tempo médio de percurso em 18:51% e 13:51%, respectivamente / Abstract: Traffic is an ever increasing problem, draining resources and aggravating pollution. In Sao Paulo, for instance, financial losses caused by traffic represent a sum of about R$33 billions a year. In this work we've developed a system that puts together the areas of Crowd Simulation and Probabilistic Planning to optimize fixed time traffic lights. Although both areas present good algorithms their use is limited by their reliance on specialists, whether to describe the probabilistic planning problem or to analyze the data produced by the simulations. Our approach contributes to minimize this dependence by using cellular automata simulations to generate the data that is used to describe the probabilistic planning problem. This allows us to: (i) reduce the amount of data collection, since the data is now generated by the simulator and (ii) produce good policies for fixed time traffic light control without the intervention of specialists to analyze the data. In the two tests performed the solution proposed by the system was able to reduce travel times by 18:51% and 13:51%, respectively / Mestrado / Ciência da Computação / Mestre em Ciência da Computação
52

Scheduling activities under spatial and temporal constraints to populate virtual urban environments / Ordonnancement d'activité sous contraintes temporelles et spatiales, pour le peuplement d'environnements virtuels

Jørgensen, Carl-Johan 17 July 2015 (has links)
Les modèles de simulation de foules visent généralement à produire des foules visuellement crédibles avec l'intention d'insuffler de la vie à des environnements virtuels. Notre travail se concentre sur la génération de comportements statistiquement cohérents qui peuvent être utilisés pour piloter des modèles de simulation de foules sur de longues périodes de temps, jusqu'à plusieurs jours. Dans les foules réelles, les comportements des individus dépendent principalement de l'activité qu'ils ont l'intention d'effectuer. La façon d’ordonnancer cette activité repose sur l'interaction étroite qui existe entre l'environnement, les contraintes spatiales et temporelles associées à l'activité et les caractéristiques personnelles des individus. Par rapport à l'état de l'art, notre modèle gérer mieux cette interaction. Nos principales contributions se situent dans le domaine de l'ordonnancement d'activités et de la planification de chemin. Dans un premier temps, nous proposons un processus d'ordonnancement d'activités individuelles et son extension aux activités coopératives. Basé sur les descriptions de l'environnement, des activités désirées et des caractéristiques des agents, ces processus génèrent une séquence de la tâche pour chaque agent. Des lieux où ces tâches doivent être effectuées sont sélectionnés et un timing relâché est produit. Cet ordonnancement est compatible avec les contraintes spatiales et temporelles liées à l'environnement et à l'activité prévue par l'agent et par d'autres agents en coopération. Il prend également en compte les caractéristiques personnelles des agents, induisant de la diversité dans les ordonnancements produits. Nous montrons que notre modèle produit des comportements statistiquement cohérents avec ceux produits par des personnes dans les mêmes situations. Dans un second temps, nous proposons un processus de planification de chemins hiérarchique. Il repose sur un processus d'analyse de l'environnement automatique qui produit une représentation hiérarchique sémantiquement cohérente des villes virtuelles. La nature hiérarchique de cette représentation est utilisée pour modéliser différents niveaux de prise de décisions. Un chemin grossier est d'abord calculé, puis raffiné pendant la navigation lorsque de l'information pertinente est disponible, permettant ainsi à l'agent d'adapter son chemin à des événements inattendus. Le modèle proposé gère des décisions rationnelles à long terme guidant la navigation des agents dans les villes virtuelles. Il prend en compte la forte relation entre le temps, l'espace et l'activité pour produire les comportements des agents plus crédibles de. Il peut être utilisé pour peupler facilement des villes virtuelles avec des foules au sein desquelles des phénomènes observables émergent de l'activité individuelle. / Crowd simulation models usually aim at producing visually credible crowds with the intent of giving life to virtual environments. Our work focusses on generating statistically consistent behaviours that can be used to pilot crowd simulation models over long periods of time, up to multiple days. In real crowds, people's behaviours mainly depend on the activities they intend to perform. The way this activity is scheduled rely on the close interaction between the environment, space and time constraints associated with the activity and personal characteristics of individuals. Compared to the state of the art, our model better handle this interaction. Our main contributions lie in the domain of activity scheduling and path planning. First, we propose an individual activity scheduling process and its extension to cooperative activity scheduling. Based on descriptions of the environment, of intended activities and of agents' characteristics, these processes generate a task schedule for each agent. Locations where the tasks should be performed are selected and a relaxed agenda is produced. This task schedule is compatible with spatial and temporal constraints associated with the environment and with the intended activity of the agent and of other cooperating agents. It also takes into account the agents personal characteristics, inducing diversity in produced schedules. We show that our model produces schedules statistically coherent with the ones produced by humans in the same situations. Second, we propose a hierarchical path-planning process. It relies on an automatic environment analysis process that produces a semantically coherent hierarchical representation of virtual cities. The hierarchical nature of this representation is used to model different levels of decision making related to path planning. A coarse path is first computed, then refined during navigation when relevant information is available. It enable the agent to seamlessly adapt its path to unexpected events. The proposed model handles long term rational decisions driving the navigation of agents in virtual cities. It considers the strong relationship between time, space and activity to produce more credible agents' behaviours. It can be used to easily populate virtual cities in which observable crowd phenomena emerge from individual activities.
53

Da modelagem de plantas a dinamica de multidões : um modelo de animação comportamental bio-inspirado / From plant modeling to crowd dynamics : a bio-inspired behavioral animation model

Bicho, Alessandro de Lima 14 August 2018 (has links)
Orientadores: Leo Pini Magalhães, Soraia Raupp Musse / Acompanha 1 CD-ROM / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-14T12:44:21Z (GMT). No. of bitstreams: 1 Bicho_AlessandrodeLima_D.pdf: 3153035 bytes, checksum: 02699fbfe11ede429a8d387c957cfb0d (MD5) Previous issue date: 2009 / Resumo: Este trabalho apresenta um método para simulação de multidões baseado no algoritmo de colonização do espaço. Este algoritmo foi originalmente proposto para modelar padrões de nervuras em folhas vegetais e de ramificações em árvores. A técnica baseia-se na competição por espaço entre nervuras ou ramificações durante o crescimento vegetal. Adaptado à simulação de multidões, o algoritmo de colonização do espaço visa simular a competição por espaço durante o movimento dos pedestres. Vários comportamentos observados em multidões reais, tais como evitar colisões, variar a velocidade de deslocamento do pedestre em função da densidade populacional e formar vias (lanes) de pedestres, nas quais o pedestre seguirá aquele imediatamente a sua frente, cuja direção e sentido são similares, são propriedades do algoritmo. O modelo de simulação de multidões proposto também caracteriza-se pela simplicidade de implementação, robustez e eficência computacional, permitindo, de acordo com o ambiente de simulação adotado, o controle interativo da multidão simulada. / Abstract: This work presents a method for crowd simulation based on the biologically-motivated space colonization algorithm. This algorithm was originally introduced to model leaf venation patterns and the branching architecture of trees. It operates by simulating the competition for space between growing veins or branches. Adapted to crowd modeling, the space colonization algorithm focuses on the competition for space among moving agents. Several behaviors observed in real crowds, including collision avoidance, relationship of crowd density and speed of agents, and the formation of lanes in which people follow each other, are properties of the algorithm. The proposed crowd modeling method is simple to implement, robust, computationally efficient, and suited to the interactive control of simulated crowds. / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica
54

Anonymita v P2P sítích / Anonymity in P2P Networks

Brunai, Adam January 2014 (has links)
Freedom of speech and the right to privacy are maybe the most important elements of a modern society, yet the rights are often violated. This fact was the main reason for writing this thesis covering P2P network models, anonymity, censorship resistance and their use in real P2P networks and publishing systems. We discuss their effectiveness and suitability for specific purposes, but also the security considerations of their use. The second part of this thesis presents the LSPP publishing protocol, which is an library implementation of an anonymous censorship resistant P2P network. Finally, we analyze the proposed protocol and compare it with existing solutions.
55

Eufunkce a dysfunkce v teoriích kolektivního jednání / Eufunction and dysfunction in theories of collective action

Kinská, Michaela January 2013 (has links)
In this work, we deal with theories of collective action. To categorize the researchers used information from the functionalist approach. The aim is to provide an overview of sociologists concerned with theories of collective action, i. e. various forms of collective action. Mainly for this work is the concept of function and its distribution eufunction and dysfunction as two poles. Researchers are closer to those poles. The inclusion of researchers in these poles are still dealing with other characteristics that unite and differentiate. In the first chapters of the thesis deals with the functionalist concepts and theories of collective action. The next chapter is already engaged functionalist categorization and other characteristics researchers. The chapter is divided into two parts, which correspond to two functionalist terms, i. e. eufunction and dysfunction. Keywords functionalism, collective action, eufunction, dysfunction, crowds, social movements, revolutions, R. K. Merton, T. Parsons
56

Almond Overflow & Other Stunts

Pine, Gabriel 05 May 2023 (has links)
No description available.
57

An Investigation of an Example-Based Method for Crowd Simulations

Malmström, David, Kaalen, Stefan January 2017 (has links)
The problem of simulating a crowd to see how it would behave in certain situations or just to create a realistic-looking scene to be used in a movie or video game is important and complex, and there are many different methods to solve it. This project is primarily an investigation of the example-based crowd simulation method described in the article "Crowds by Example" by Lerner et al. In the article, traced video footage of crowds are used to create a data set. The simulation program continuously finds situations in the data set that resembles the current situations in the simulation and updates the simulation thereby. We implemented this for around 10 agents using Unity 3D. Example-based crowd simulations does not only, like some other types of crowd simulation methods (for example ORCA), take collision avoidance into account but also the more complex ways the human mind thinks and therefore does not always behave as one would predict. The main conclusion is that this method of simulating crowds has the potential to create more realistic simulations than other forms of crowd simulations. The downsides are that the time the program spends creating simulations can quickly get very high and to make realistic simulations a lot of video footage must be filmed and then traced.
58

Gregarious space, uncertain grounds, undisciplined bodies the Soviet avant-garde and the 'crowd' design problem

Ziada, Hazem 05 April 2011 (has links)
This thesis proposes a theoretical framework for spatial inquiry into conditions of radical social gregariousness, through probing the crowd design problem in the work of the Soviet Rationalist architects (1920s-30s) - particularly their submissions to the Palace of Soviets competition (Moscow 1931-3). Legitimizing the crowd construct as an index of collective consciousness, and examining the early-modern revolutionary crowd's struggles for proclaiming its self-consciousness, this thesis investigates the interwar political phenomenon of amassing large crowds within buildings as a device for constructing collective social relations. The research project is divided into two main parts. The first is concerned with the crowd design problem, identifying this problem not just as the technical task of accommodating large political crowds, but as the basis of the formulation a new kind of conceptual intent in architecture. Finding the competition brief inadequate to in-depth formulation, the thesis investigates three primary sources for the crowd design problem: mass-events, revolutionary-theatre and revolutionary-art. Four components comprise the Crowd Design Problem each seeking legitimacy in the mass of crowd-bodies: i) the problem of crowd configurations; ii) challenges from the kinesthetic-space conception evoked by theatrical director V.E. Meyerhold's Biomechanics; iii) the legitimacy of 'the object' within a spatial-field of intersubjectivity; and iv) the challenge of 'seeing' crowds from immersive viewpoints counteracting representational filters of class privilege. Part-II focuses on the response of the Rationalists--one of the groups participating in the competition--to the crowd design problem. The study unearths in their designs a logic of space-making founded in the construction of inter-subjective states of consciousness radically different from prevailing individualistic conceptions of social space. To explain this logic of space-making, it proposes the notion of Gregarious Space--a theoretical framework of inquiry into what Marx called "species-being", taking radical gregariousness as the primary, generative condition of society. Besides drawing on morphological principles, social theory, historical analyses, and philosophical reflections, the notion of Gregarious Space is found to be particularly amenable to design propositions. Within the proposed theoretical framework, the Rationalists' design-proposition of curved-grounds, dense notations, textured co-visibilities and empathetic graphic conventions - all comprise a founding spatial-principle trafficking in rhythmic fields between subjects and against non-commodified objects: a principle which challenges the material domain of Productivist Constructivism as well as Historical Materialism's canonical constructs of alienation. Moreover, its uncertain kinesthetics sustain dynamic, aleatory states of consciousness which subvert prevailing disciplinary techniques of Panopticon inspection.
59

Otimização de multidões em jogos digitais utilizando CUDA

Bardella, Tiago Ungaro 19 October 2015 (has links)
Made available in DSpace on 2016-03-15T19:38:03Z (GMT). No. of bitstreams: 1 TIAGO UNGARO BARDELLA.pdf: 2553991 bytes, checksum: f8e6ba33f7c930ee81f6b64116f495ff (MD5) Previous issue date: 2015-10-19 / The history of digital games shows, since the beginning, games which uses many types of enemy models to confront and many types of characters to control, like Real-Time Strategy games, for example. These huge amount of models into an important scene are called crowds. The crowds needs a high computer performance and specific algorithms in their interaction control to avoid immersion loss into a game by problems which may happen if the crowds are not treated accordingly. With the popularization of graphic board languages like NVIDIA CUDA, new algorithms were created to easily increase the performance of crowds in digital games and their overwhelming superiority compared to the methods used in linear programming were proved in many researches. The goal of this work is to use these GPU techniques as base to implement a new API using CUDA language that will present better performance and simplicity compared to the others algorithms on the area of crowds in digital games. After the project conclusion, the created API turned easier the crowd treatment to digital game developers using Unity3D integrated with API TBX, that now only need to include a DLL in the project instead creating na algorithm for crowd treatment from the beginning, which takes a huge amount of time from development. / O histórico dos jogos digitais apresenta, desde seu princípio, jogos que utilizam diversos modelos de inimigos para enfrentar ou diversos modelos de personagens para controlar, como os jogos Real-Time Strategy por exemplo. Essas grandes quantidades de modelos que compõem uma cena importante são chamadas de multidões. As multidões necessitam de um alto poder computacional e algoritmos específicos para seu tratamento para evitar a perda de imersão dentro de um jogo pelos problemas que podem acontecer caso as multidões não sejam tratadas adequadamente. Com o surgimento de linguagens de placas gráficas como a NVIDIA CUDA, novos algoritmos foram criados para melhor trabalhar com o desempenho de multidões em jogos digitais e sua superioridade em comparação com os métodos utilizados em programação sequencial foi comprovada em diversos estudos. O objetivo deste trabalho é se basear nestas técnicas de GPU para implementar uma nova API usando tecnologia CUDA que visa melhorar os algoritmos existentes para tratamento de multidões em jogos digitais em termos de desempenho e simplicidade de implementação. Com a conclusão do projeto, a API criada facilitou o tratamento de multidões para desenvolvedores de jogos digitais com a game engine Unity3D integrada com a API TBX de simulação de multidões, que agora apenas precisam incluir uma DLL em seu projeto ao invés de criar um algoritmo próprio de tratamento de multidões do início, o que demanda tempo de desenvolvimento.
60

The Information Value of Unstructured Analyst Opinions / Studies on the Determinants of Information Value and its Relationship to Capital Markets

Eickhoff, Matthias 29 June 2017 (has links)
No description available.

Page generated in 0.0284 seconds