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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.
11

Comparative assessment of human observation in virtual and physical reality

Larif, Oumaima 09 August 2019 (has links)
Virtual Reality (VR) is a computer-generated simulation of an environment that can be interacted with a seemingly real or physical way by a person using special electronic equipment. VR techniques have the potential to reduce design cycle times and reduce or eliminate physical prototyping costs if the human performance in VR is truly comparable to physical reality. In this research, human oversight of an assembly process in virtual reality (VR) and physical reality is compared for the ability to detect deviations (errors) in parts. This is relevant to verifying the use of VR to assess the vulnerability of cyber-physical systems with human observation.
12

Estimation of traversed distance in a virtual environment

Kline, Paul Brian 01 January 1999 (has links)
No description available.
13

Develop, build, and test a virtual lab to support vulnerability training system

Akgul, Turgut, Kargin, Coskun 09 1900 (has links)
Approved for public release; distribution is unlimited / A computer security virtual lab architecture was developed and tested for functionality and performance. Four Dell PowerEdge 1650, dual processor, blade servers were configured as host machines with VMware and VNC running on a Linux RedHat 9 Kernel. An Apache-Tomcat web server was configured as the external interface to lab users. Web content was created, the site was secured with SSL, and Java Servlet functionality was enabled. Host machine performance was tested under various load conditions. Analysis indicated that, for our architecture, that the average host machine CPU load was [about]12 % while the average memory load was [about]33 %. We conclude that for the cost and space requirements of 5 1U blade servers we have configured an equivalent 20 computer lab. Performance tests show that the virtual lab could scale easily from 4 - 30 computers. / 1st Lieutenant, Turkish Army / 1st Lieutenant, Turkish Army
14

The case for virtual property

MacDonald, Michaela January 2017 (has links)
Virtual assets should be treated as a species of property. Users of virtual environments have legitimate expectations about acquiring legal interests in virtual assets as they would in their physical counterparts under similar circumstances. There are two sources of these expectations. Firstly, it is the architecture of virtual environments, the existence of virtual economies, and the property-like characteristics of virtual assets that frame users' expectations. Secondly, providers' representations and conduct either explicitly authorise or tolerate virtual asset transactions. As a result, issues of title and ownership arise. The existing legal framework fails to deal properly with these issues. Currently applicable laws, such as contract, intellectual property or consumer protection law, do not recognise users' expectations as legitimate. However, property law could provide the necessary answers by treating virtual assets as part of the law of property. The theoretical foundations of property law inform us about the origins, justifications and consequences of property rights, as well as their role in allocating valuable resources and resolving social conflict. The concept of virtual property entails property rights in virtual assets, which as durable, separable things of independent value. In consequence, a new category of virtual property would resolve the different and unjustified treatment of virtual assets. Virtual property recognizes and protects users' legal interest in virtual assets, based on their legitimate expectations.
15

The virtual environment operating system : derivation, function, and form /

Coco, Geoffrey P. January 1993 (has links) (PDF)
Thesis (M.S.E.)--University of Washington, 1993. / Includes bibliographical references (leaves [116]-119).
16

Develop, build, and test a virtual lab to support vulnerability training system /

Kargin, Coskun. Akgul, Turgut. January 2004 (has links) (PDF)
Thesis (M.S. in Computer Science)--Naval Postgraduate School, Sept. 2004. / Thesis advisor(s): Richard M. Harkins. Includes bibliographical references (p. 75-76). Also available online.
17

Design and Perception of Diverse Virtual Avatars in Immersive Environments

Do, Tiffany D 01 January 2024 (has links) (PDF)
Virtual humans and avatars have become integral components of immersive technologies, shaping various aspects of virtual worlds. This dissertation investigates the nuanced interactions between user demographics and virtual avatars, exploring their impact on perception, embodiment, and persuasive communication. The first study investigates the effectiveness of different speech fidelity levels in virtual humans, revealing gender-dependent perceptions of trustworthiness. Building on this, this dissertation introduces the \textit{Virtual Avatar Library for Inclusion and Diversity} (\textit{VALID}), offering a comprehensive resource for advancing racial diversity and inclusion in virtual environments. Through rigorous validation studies, we shed light on the perception of avatar characteristics worldwide, emphasizing the importance of accurately representing diverse demographics. This dissertation also examines the influence of matching avatar demographics to user demographics on sense of embodiment in virtual reality. We found significant effects of matched ethnicity and gender on sense of embodiment, revealing the importance of providing diverse representations for users in applications and experiments. Furthermore, we explored the intricate interactions between user demographics and avatar matching effects, revealing how some demographics may be disproportionally affected by unmatched avatars. Through a diverse array of experiments and validation studies, this dissertation provides valuable insights into the design, perception, and implications of virtual representations in immersive technologies and paves the way for more inclusive and effective virtual environments.
18

Prototipação virtual de plataforma agrícola móvel / Virtual prototyping of mobile agricultural platform

Vale, Heleno Murilo Campeão 25 August 2005 (has links)
A realidade virtual (RV) tem como principal área de aplicação o entretenimento. Porém, nos últimos anos, devido ao desenvolvimento acelerado do hardware de computadores, a RV se tornou mais acessível, sendo amplamente utilizada, também, nas áreas acadêmica e industrial. Uma parte da RV que, a cada dia, se torna mais importante para as áreas da engenharia é a prototipação virtual (PV). Normalmente, a prototipação física de um produto pode ser dispendiosa e inviável para determinados projetos. Nesses casos, a PV pode ser utilizada para evitar gastos desnecessários, alcançando resultados satisfatórios. Neste trabalho são descritos os passos referentes à implementação de um protótipo virtual, baseado no anteprojeto em desenvolvimento do projeto de pesquisa do Laboratório de Simulação e Controle de Sistemas Discretos do SEM-EESC, com auxílio pesquisa FAPESP processo: 2003/06582-0 \"Veículo agrícola autônomo (VAA): uma plataforma para desenvolvimento de tecnologias de navegação autônoma e para aquisição de dados em agricultura de precisão\". Além da descrição da implementação do protótipo virtual, neste trabalho são analisadas cinco ferramentas de desenvolvimento virtual disponíveis para testes no laboratório de simulação: 3Dcanvas Freeware, WorldUp, EON Studio 4.0, WEBOTS e EON Professional. Os critérios de avaliação das ferramentas foram baseados nas necessidades principais do projeto em questão, como implementação de centros de massa distribuídos, criação de terrenos não-estruturados (constituídos por morros, buracos etc.), controles de tração, torque, além de outras características físicas essenciais. A fase inicial da implementação foi desenvolvida em EON Studio 4.0. Devido à falta de recursos disponíveis nessa ferramenta, a fase final da implementação foi desenvolvida no software EON Professional. A análise do comportamento da plataforma em terrenos não-estruturados, a verificação dos ângulos de inclinação suportados e a análise da reconfiguração das laterais da plataforma são alguns dos resultados obtidos. / Virtual reality (VR) has entertainment as its main area of application. However, over the last few years, due to a fast-paced development of computers hardware, VR has become more accessible, being widely used both in the academic and industrial areas. A part of VR that is becoming more important for the engineering areas is virtual protoyping (VP). Normally, the physical prototyping of a product can be expensive and impracticable for some projects. In such cases, VP can be used to prevent unnecessary operating costs, reaching satisfactory results. In this paper, the steps of the implementation of a virtual prototype are described, based on the first draft in development of the research project of the Laboratory of Simulation and Control of Discrete Systems of SEM-EESC, with FAPESP support process: 2003/06582-0 \"Autonomous agricultural vehicle (AAV): a platform for development of technologies for independent navigation and for data acquisition in precision agriculture\". Besides the description of the virtual prototype implementation, in this paper five tools for virtual development, available for tests in the laboratory of simulation, are analyzed: 3Dcanvas Freeware, WorldUp, EON Studio 4.0, WEBOTS and EON Professional. The criteria of evaluation of the tools were based on the main necessities of the project, such as the implementation of distributed centers of mass, not-structuralized land creation (made up of hills, holes etc.), traction controls,torque, besides other essential physical characteristics. The initial stage of the implementation was developed at EON Studio 4.0. Due to the lack of available resources in this tool, the final stage of the implementation was developed in EON Professional software. The behavior analysis of the platform at non-structuralized lands, the verification of the supported inclination angles and the analysis of the platform laterals reconfiguration are some of the achieved results.
19

Prototipação de um torno CNC utilizando realidade virtual. / Prototyping of a lathe CNC using virtual reality.

Valerio Netto, Antonio 18 September 1998 (has links)
Este trabalho tem como objetivo o desenvolvimento de um procedimento para a implementação de um protótipo de um torno CNC utilizando realidade virtual. Enfocando principalmente, seu sistema de intertravamento (funcionalidade) e seu modelo geométrico (design físico). Este trabalho se inicia com uma revisão sobre o emprego da realidade virtual em várias áreas inclusive na indústria, e posteriormente discorre sucintamente sobre a estrutura de programação e a justificativa da utilização da ferramenta de construção de ambientes virtuais utilizada no projeto. Em seguida enfoca as especificações do torno CNC virtual e do intertravamento proposto, inclusive com explicações dos passos utilizados para a obtenção da lógica funcional do torno. Adiante é exposto o procedimento adotado para a implementação do protótipo do torno virtual e quais foram os passos utilizados para o desenvolvimento do modelo gráfico incluindo as soluções encontradas para implementação das características deste modelo interativo. Por fim o trabalho apresenta um breve relato sobre a possibilidade do projeto ser empregado nas áreas de prototipação virtual, treinamento e markenting de produtos, e também sugere um roteiro para desenvolvimento de uma máquina-ferramenta utilizando a prototipação virtual. / The aim of this work is the developing of a procedure for the implementation of a CNC lathe prototype using virtual reality, focusing mainly in its interlocking system (functionality) and its geometrical model (physical design). This work starts with a revision about the using of VR in many areas including industry, and afterwards refers briefly on the programming structure and the justificative for the use of the virtual-environment-building tool used in this project. Thereafter it focus the virtual CNC lathing machine’s specifications and the proposed interlocking, with explanations for the steps used in the obtaining of the machine’s functional logic. Later on, are exposed the chosen procedure for the implementation of the virtual machine prototype and which were the steps used for the developing of the graphical model including the found solutions for the implementation of this interactive model. Finally, the work presents a brief report about the possibility of using this project in the virtual prototyping, training and product marketing areas, and also suggests a procedure for the development of a machine tool using virtual prototyping.
20

Prototipação virtual de plataforma agrícola móvel / Virtual prototyping of mobile agricultural platform

Heleno Murilo Campeão Vale 25 August 2005 (has links)
A realidade virtual (RV) tem como principal área de aplicação o entretenimento. Porém, nos últimos anos, devido ao desenvolvimento acelerado do hardware de computadores, a RV se tornou mais acessível, sendo amplamente utilizada, também, nas áreas acadêmica e industrial. Uma parte da RV que, a cada dia, se torna mais importante para as áreas da engenharia é a prototipação virtual (PV). Normalmente, a prototipação física de um produto pode ser dispendiosa e inviável para determinados projetos. Nesses casos, a PV pode ser utilizada para evitar gastos desnecessários, alcançando resultados satisfatórios. Neste trabalho são descritos os passos referentes à implementação de um protótipo virtual, baseado no anteprojeto em desenvolvimento do projeto de pesquisa do Laboratório de Simulação e Controle de Sistemas Discretos do SEM-EESC, com auxílio pesquisa FAPESP processo: 2003/06582-0 \"Veículo agrícola autônomo (VAA): uma plataforma para desenvolvimento de tecnologias de navegação autônoma e para aquisição de dados em agricultura de precisão\". Além da descrição da implementação do protótipo virtual, neste trabalho são analisadas cinco ferramentas de desenvolvimento virtual disponíveis para testes no laboratório de simulação: 3Dcanvas Freeware, WorldUp, EON Studio 4.0, WEBOTS e EON Professional. Os critérios de avaliação das ferramentas foram baseados nas necessidades principais do projeto em questão, como implementação de centros de massa distribuídos, criação de terrenos não-estruturados (constituídos por morros, buracos etc.), controles de tração, torque, além de outras características físicas essenciais. A fase inicial da implementação foi desenvolvida em EON Studio 4.0. Devido à falta de recursos disponíveis nessa ferramenta, a fase final da implementação foi desenvolvida no software EON Professional. A análise do comportamento da plataforma em terrenos não-estruturados, a verificação dos ângulos de inclinação suportados e a análise da reconfiguração das laterais da plataforma são alguns dos resultados obtidos. / Virtual reality (VR) has entertainment as its main area of application. However, over the last few years, due to a fast-paced development of computers hardware, VR has become more accessible, being widely used both in the academic and industrial areas. A part of VR that is becoming more important for the engineering areas is virtual protoyping (VP). Normally, the physical prototyping of a product can be expensive and impracticable for some projects. In such cases, VP can be used to prevent unnecessary operating costs, reaching satisfactory results. In this paper, the steps of the implementation of a virtual prototype are described, based on the first draft in development of the research project of the Laboratory of Simulation and Control of Discrete Systems of SEM-EESC, with FAPESP support process: 2003/06582-0 \"Autonomous agricultural vehicle (AAV): a platform for development of technologies for independent navigation and for data acquisition in precision agriculture\". Besides the description of the virtual prototype implementation, in this paper five tools for virtual development, available for tests in the laboratory of simulation, are analyzed: 3Dcanvas Freeware, WorldUp, EON Studio 4.0, WEBOTS and EON Professional. The criteria of evaluation of the tools were based on the main necessities of the project, such as the implementation of distributed centers of mass, not-structuralized land creation (made up of hills, holes etc.), traction controls,torque, besides other essential physical characteristics. The initial stage of the implementation was developed at EON Studio 4.0. Due to the lack of available resources in this tool, the final stage of the implementation was developed in EON Professional software. The behavior analysis of the platform at non-structuralized lands, the verification of the supported inclination angles and the analysis of the platform laterals reconfiguration are some of the achieved results.

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