With the increased use of crowd simulation in animation, specification of crowd motion can be very time consuming, requiring a lot of user input. To alleviate this cost, we wish to allow a user to interactively manipulate the many degrees of freedom in a crowd, whilst accounting for the limitation of low-dimensional signals from standard input devices. In this thesis we present two approaches for achieving this: 1) Combining shape deformation methods with a multitouch input device, allowing a user to control the motion of the crowd in dynamic environments, and 2) applying a data-driven approach to learn the mapping between a crowd’s motion and the corresponding user input to enable intuitive control of a crowd. In our first approach, we represent the crowd as a deformable mesh, allowing a user to manipulate it using a multitouch device. The user controls the shape and motion of the crowd by altering the mesh, and the mesh in turn deforms according to the environment. We handle congestion and perturbation by having agents dynamically reassign their goals in the formation using a mass transport solver. Our method allows control of a crowd in a single pass, improving on the time taken by previous, multistage, approaches. We validate our method with a user study, comparing our control algorithm against a common mouse-based controller. We develop a simplified version of motion data patches to model character-environment interactions that are largely ignored in previous crowd research. We design an environment-aware cost metric for the mass transport solver that considers how these interactions affect a character’s ability to track the user’s commands. Experimental results show that our system can produce realistic crowd scenes with minimal, high-level, input signals from the user. In our second approach, we propose that crowd simulation control algorithms inherently impose restrictions on how user input affects the motion of the crowd. To bypass this, we investigate a data-driven approach for creating a direct mapping between low-dimensional user input and the resulting high-dimensional crowd motion. Results show that the crowd motion can be inferred directly from variations in a user’s input signals, providing a user with greater freedom to define the animation.

Thesis (Ph.D.) -- University of Adelaide, Dept. of Computing Science, 1976.

No description available.

Artists require control and predictability over physically based simulations to create their required animation. This control can lead to reduced iteration time to get the desired simulation results. Controlling cloth simulations can require manual effort to create goal keyframes for control algorithms to match. Current techniques and research utilize a keyboard and mouse to create these goal keyframes. Other research has looked at using a virtual reality (VR) head-mounted display with controllers to improve the experience of completing similar animation tasks. However, we are not aware of any research that attempts to use VR as a tool to assist artists in the process of cloth simulation. This work explores using VR to create goal keyframes of a cloth mesh for control algorithms to further artists' ability to produce and control cloth simulations. We created a system where users can produce goal keyframes using both a keyboard and mouse and using VR. A user study was conducted (n=20) utilizing this system for keyframing tasks. We found that most participants preferred to use the system in VR and found it fun and intuitive, with each input method having their own strengths in the cloth keyframe sculpting process. We also found the timing and accuracy of using VR to be comparable to using a keyboard and mouse, despite minimal VR experience among participants.

Orientadores: João Alexandre F. R. Pereira, Maria de Fatima dos S. Lopes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-07-26T19:33:57Z (GMT). No. of bitstreams: 1 Pires_CarlosAugustodeMoraes_D.pdf: 5756765 bytes, checksum: 2dc4d2764d6474896a777d6ffc991d18 (MD5) Previous issue date: 2000 / Resumo: O processo de refonna catalítica da nafta, voltado para a produção de compostos aromáticos (benzeno, tolueno e xilenos), foi o tema abordado neste estudo. Considerou-se um típico processo semi-regenerativo, no qual existem quatro reatores radiais em série intercalados com quatro fornalhas que são utilizadas para aquecer as correntes que alimentam os reatores. A modelagem dos reatores foi proposta para os regimes estacionário e transiente e foi considerado um sistema reacional simplificado, envolvendo apenas dez compostos químicos relacionados através de cinco reações. A desativação do catalisador faz parte do modelo cinético e a expressão da taxa de fonnação de coque é baseada na condensação do aromático. Este modelo foi simulado a partir de um programa de computador construí do em linguagem FORTRAN, chegando-se a resultados compatíveis com os encontrados em literatura. Desta fonna, foi possível efetuar um estudo sobre os efeitos das variáveis operacionais nas concentrações dos produtos deste processo e várias conclusões importantes foram obtidas. Após analisar as relações entre os produtos originários da refonna com as variáveis operacionais, foi proposta uma estratégia de controle em cascata para manter a concentração de aromático no "setpoint" desejado. O objetivo da aplicação desta estratégia de controle é o de compensar os efeitos da desativação do catalisador, bastando para isso aumentar a temperatura da corrente de entrada dos reatores. A malha secundária, do controle em cascata, controla a temperatura de entrada dos reatores. Foram utilizados os controladores PID, DMC e LDMC no intuito de verificar o melhor desempenho desta malha. Estes controladores foram elaborados em linguagem FORTRAN e através da simulação destes casos foram obtidas infonnações que pennitiram concluir que o controlador LDMC é o mais apropriado. Para a malha primária, que controla a concentração de aromático, impondo as temperaturas ótimas de entrada para cada reator (setpoints" da malha secundária), foi utilizado o controlador LDMC com duas opções de configuração para a matriz dinâmica. A primeira opção considera o sistema como sendo de múltiplas entradas e única saída (MISO), com as temperaturas representando as variáveis manipuladas e a concentração de aromático a controlada. A segunda opção supõe que o sistema possui única entrada e única saída (SISO), a variável manipulada é a W AIT (que é a soma ponderada das temperaturas de entrada dos reatores, levando em conta a quantidade de catalisador em cada um dos leitos) e a variável controlada é a concentração de aromático. Observa-se que não houve diferença significativa entre estas duas opções para a malha primária, notando-se apenas uma ligeira vantagem para o caso MISO em função da maior atividade do catalisador. Como conclusão deste trabalho, foi possível verificar os vários aspectos da refonna catalítica da nafta inerentes ao processo de obtenção de aromáticos. Entretanto, outras pesquisas nesta linha devem ser realizadas para conseguir, dentre outras coisas, diminuir a defasagem existente de infonnações entre a tecnologia atual e a teoria disponível, sendo que esforços como este devem ser incentivados para obtenção de mais conhecimentos sobre o processo / Abstract: The theme of this study is the process of catalytic refonning for aromatics (benzene, toluene and xilenes). There were considered a typical semiregenerative process, with serial arrange of four radial reactors preceded by four furnaces used to pre-heat the reactors feed. There were proposed stationary and transient for the reactors. A simplified reacctional system were considered, involving only ten chemical compounds related through five reactions. The kinetic model inc1ude the deactivation of the catalyst and the rate of coke fonnation is based on aromatic condensation. The model was simulated in a computer FORTRAN code and the achieved results are compatible with the literature ones. It was then possible to study the effects of operational variables in the products concentrations and several important conclusions were obtained. The relationship among the reforming process products with operational variables were analyzed and a cascade control strategy was proposed to maintain the aromatic concentration in the desired set point. The objective of this control strategy is to compensate the catalyst deactivation effects, and its only action is to increase the temperature of the feed reactors. The secondary loop in the cascade control strategy controls the temperature of the feed ofthe reactors. Controllers PID, DMC and LDMC were tested in order to verify which is the one what maximizes the loop performance. The controllers were programmed in a FORTRAN code and the simulation results shows that the controller LDMC is the most appropriate. For the primary loop, which controls the aromatic concentration, imposing the optimal temperature in each reactor feed ( set point of secondary loop) the controller LDMC was used with two possible configuration of the dynamic matrix. The first option considers the system with multiple entrances and only a exit (MISO), with the temperatures representing the manipulated variables and the aromatic concentration as the controlled one. The second option supposes that the system has only one entrance and only one exit (SISO). The manipulated variable is WAIT (weighted average inlet temperature) the controlled variable is also the aromatic concentration. Both options for primary loop are equivalent, the MISO options is slightly better than the often one because of largest catalyst activity. In this work, it was verified several aspects inherent of catalytic naphtha refonning process for the production of aromatics. Other researches in this line should he done in order to reduce the existent gap of information between current technology and available theory, and other efforts should be motivated for obtaining a better knowledge of the processo / Doutorado / Sistemas de Processos Quimicos e Informatica / Doutor em Engenharia Química

This thesis describes the finish-painting area at ŠKODA AUTO a.s. company in Mladá Boleslav. The logistic operations and transporter technology in this production hall are described here. Furthermore this thesis is concerned to sequence making of car body before the finish-painting area. The output evaluation is make of experiments and comparison of influence of an old logic of choosing a colored block with a new control logic for car body with influence on the correct shifting of car body according to a sequence number. The containers for car body including all other workplaces of the painting area are created in the Plant Simulation program.

This monograph contributes to the methodology of Agent-based Computational Economics. First, we introduce a generic simulation framework suitable for agent-based simulations featuring the support of heterogeneous agents, hierarchical scheduling, and flexible specification of design parameters. For the latter, we use an XML-based format enabling the design of flexible models, with the possibility of varying both agent population and parameterization. Further, the tool allows the definition of communication channels to single agents, or groups thereof, and handles the information exchange. Both agents and communication channels can be added and removed at runtime. To handle the heterogeneity arising from both the agents' implementations and the underlying platforms, we introduce an XML-based wrapper technique for mapping the functionality of agents living in an interpreter-based environment to a standardized JAVA interface. Second, we present a collection of artificial economic actors to be used with this framework. Their interplay is demonstrated in two fields of management science: marketing and technological choice. In the field of marketing, the question of choosing the optimal segmentation techniques for market segmentation is investigated, comparing the performance of firm agents with diverse segmentation strategies in a highly customizable artificial consumer market. In the second application, we study the influence of technological efficiency and organizational inertia on the emergence of competition when firms decide myopically. We observe the competitive reaction of a former monopolist to the advent of a new competitor to assess when new, "disruptive" technologies cause the failure of incumbent firms and investigate simple defensive strategies. (author's abstract)

Eine Absicherung der Maschinendynamik im gesamten Arbeitsraum unter Berücksichtigung des Einflusses der Maschinensteuerung kann nur durch eine mechatronische Analyse der Werkzeugmaschine auf Gesamtsystemebene erfolgen. Derart komplexe Berechnungen erfordern allerdings die Simulation von großen Verfahrbewegungen (MKS) unter Berücksichtigung der Strukturelastizitäten (FEM) sowie der Steuerung (Controls) und sind somit vor allem multi–disziplinären Virtual Prototyping Tools vorbehalten. Die erfolgreiche multi-disziplinäre WZM–Berechnung stellt außerordentlich hohe Anforderungen an die Modellbildungsgüte der einzelnen Maschinenkomponenten inklusive der Validierung des jeweils gewählten Modellierungsansatzes bzw. Detailierungsgrades. Dieses gilt insbesondere für funktionelle Komponenten wie Linearantriebe, Kugelgewindetriebe usw., da diese nicht ohne Weiteres aus einem CAD–Baugruppenmodell abgeleitet und in das Berechnungsmodell übernommen werden können. Das zur Modellierung und Simulation notwendige Expertenwissen ist in einer vordefinierten, parametrischen Komponentenbibliothek – ähnlich einem Baukastenprinzip – implementiert.

As the fidelity of computer generated imagery has increased, the need to digitally create convincing natural phenomena like fluids has become fundamental to the entertainment production industry. Because fluids are complex, the underlying physics must be computationally simulated. However, because a strictly physics-based approach is both computationally expensive and difficult to control, it does not lend itself well to the way artists and directors like to work. Directors require control to achieve their specific artistic vision. Furthermore, artistic workflows rely on quick iteration and the ability to apply changes late in the production process. In this dissertation we present novel techniques in adaptive simulation and fluid post-processing to improve artistic workflows for fluid simulation. Our methods reduce fluid simulation iteration time and provide a new way for artists to intelligently resize a wide range of volumetric data including fluid simulations. To reduce iteration time, we present a more cache-friendly linear octree structure for adaptive fluid simulation that reduces the overhead of previous octree-based methods. To increase the viability of reusable effects libraries, and to give artists intuitive control over simulations late in the production process we present a ``fluid carving" technique. Fluid carving uses seam carving methods to allow intelligent resizing on a variety of fluid phenomena without the need for costly re-simulation. We present methods that improve upon traditional seam carving approaches to address issues with scalability, non-rectangular boundaries, and that generalize to a variety of different visual effects data like particles, polygonal meshes, liquids, smoke, and fire. We achieve these improvements by guiding seams along user-defined lattices that can enclose regions of interest defined as OpenVDB grids with a wide range of shapes. These techniques significantly improve artist workflows for fluid simulation and allow visual entertainment to be produced in a more intuitive, cost-effective manner.

No presente trabalho, emprega-se a medida da concentração de etanol do combustível para efetuar correções estequiométricas de maneira direta e instantânea, a fim de eliminar o período necessário para adaptação a partir da medida do sensor de oxigênio (sonda lambda) em eventos de reabastecimento no veículo. Com o objetivo de assegurar a operação flex-fuel, foram empregados métodos para a regulação ar/combustível em malha fechada, realimentados por sensores de oxigênio (banda larga amplificada e banda estreita). O projeto foi implementado em uma ECU (Eletronic Control Unit) idealizada para desenvolvimento de rotinas de programa voltadas ao gerenciamento eletrônico para motores de combustão interna ciclo Otto, denominada Flex-ECU. A ETAS/Bosch Flex-ECU possui programação aplicada à ferramenta ASCET (Advanced Simulation and Control Engineering Tool), o qual trata-se de um código open source para sistemas embarcados de tempo real. Por fim, são exibidos resultados de controle, desempenho e eficiência do motor para diferentes composições de combustível comercializados para a frota de veículos leves em território nacional. Os experimentos revelam a dinâmica de funcionamento do controle A/C bicombustível e discute as suas principais características, com o objetivo de exemplificar métodos de otimização de sua eficiência. / In the present work, the ethanol fuel concentration is used to establish stoichiometric corrections in a direct and instantaneous manner, to eliminate the period necessary for adaptation, from the measurement of the oxygen sensor (lambda probe) in events of refueling. To ensure Flex-fuel operation, closed-loop air/fuel regulation methods were used, fed by oxygen sensors (amplified wide band and narrow band). The project was implemented in an ECU (Electronic Control Unit) designed for the development of code routines for electronic management of an Otto cycle internal combustion engine, labeled Flex-ECU. The ETAS / Bosch Flex-ECU has programming applied to the ASCET (Advanced Simulation and Control Engineering Tool) tool, which is an open source code for real time embedded systems. Finally, results of engine control, performance, and efficiency are presented for different fuel compositions available in Brazil for the fleet of light vehicles. The experiments show the dynamics of the operation of the bi-fuel A/C control and discusses its main characteristics, aiming to exemplify optimization methods of its efficiency.