Orientador: Wu Shin-Ting / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-17T00:55:23Z (GMT). No. of bitstreams: 1 SilveiraJunior_LuizGonzagada_D.pdf: 5188366 bytes, checksum: f96bd27ab9bd4ccc6af3d5865695dc14 (MD5) Previous issue date: 2005 / Resumo: Este trabalho aborda o problema de consistência de dados geométricos e topológicos no contexto de modelagem geométrica colaborativa, destacando o impacto do processamento distribuído sobre a robustez das operações geométricas e topológicas em cada transação em um ambiente computacional multiplataforma. A consistência é alcançada através de uma arquitetura fracamente acoplada, caracterizada por representações independentes das informações geométricas e gráficas dos modelos, e do emprego de algoritmos geométricos já consolidados em aplicações mono-usuário. Enquanto as informações geométricas são mantidas em um servidor dedicado, as respectivas representações gráficas são replicadas, renderizadas e exibidas localmente no espaço de trabalho de cada usuário. Assim, pode-se explorar individualmente os recursos dos equipamentos utilizados, através do ajuste dos parâmetros de renderização e visualização, sem degradar a robustez do sistema. No entanto, a separação dos modelos origina dois problemas: maior tempo de resposta em cada interação e a perda de consciência coletiva. Nós apresentamos um modelo de interação distribuída que evita a sobrecarga na comunicação, sem sacrificar a realimentação visual, através do uso de metáforas 3D. A perda de consciência coletiva é resolvida através de um conjunto de componentes de consciência coletiva e a reutilização de representações gráficas das metáforas 3D. Estes artefatos oferecem consciência de localização, perspectiva e proximidade aos participantes da colaboração. Um protótipo de modelador geométrico colaborativo, baseado na arquitetura fracamente acoplada e nos modelos de interação distribuída e consciência coletiva, foi implementado para validar nossa proposta / Abstract: This work tackles the consistency of geometric and topological data problems in the collaborative geometric modeling context, focusing on the robustness for each transaction that occurs in a multiplatform environment. We propose a loosely coupled system architecture in which geometric and graphical models are represented separately. The geometric information is kept in a dedicated server and handled through consolidated geometric algorithms, while their respective graphical representations are replicated, rendered and displayed in each end user workspaces. This allows, on the one hand, better use of the computational resources, through local adjustments of rendering and visualization parameters, without loss the robustness. On the other hand, two problems may arise: longer response time in each interaction and lost of group awareness. We present a distributed interaction model, in which the overload of the network may be avoided without sacrificing the visual feedback, through a set of 3D-metaphors. The group awareness is achieved by a set of awareness components and the reuse of graphical representations of the 3D-metaphors. They show to be very powerful in providing the awareness of the location, perspective, and proximity to the co-workers. A collaborative geometric modeller prototype, based on loosely coupled architecture and interaction and group awareness models, has been implemented to validate our proposal / Doutorado / Engenharia de Computação / Doutor em Engenharia Elétrica

Quasi-geostrophic (QG) analysis of the atmosphere utilizes predefined isobaric surfaces to ascertain vertical motion. One equation of the QG system is the omega equation that states that vertical forcing results from differential vorticity advection and thickness advection. Two problems arise when using the QG omega equation: the forcing terms are not independent and must be analyzed simultaneously, and vertical forcing is visually noisy. Both issues are resolved using a smoothing and quantification technique that applies the QG omega equation. The analysis fields from a selection of events were chosen from the North American Mesoscale model. Using a finite differencing methodology dependent on the wavelength of synoptic features, values of vertical forcing were calculated using the omega equation. The calculated omega field correlated well with model omega while also quantifying and visualizing large perturbations in vertical forcing. The method allows for quick diagnosis of forcing type and strength within the atmosphere.

Seit einigen Jahren hat sich Mathcad als universelle Mathematiksoftware an vielen Universitäten, Instituten und in Unternehmen bewährt. An der Professur Maschinenelemente der TU Chemnitz wird Mathcad derzeit u.a. bei der Entwicklung einer vollkommen neuartigen Riemenscheibenkupplung für PKW-Kältemittelverdichter eingesetzt. Hierfür wurde ein mathematisches Modell entwickelt, mit dem sich die Bauteilbelastungen sowie die dynamischen Vorgänge in der Kupplung simulieren lassen. Bei der Analyse und Optimierung solcher technischen Systeme besteht häufig der Wunsch, die Bewegung der Bauteile und die wirkenden Kräfte direkt in Mathcad dreidimensional zu visualisieren, ohne dass dafür ein CAD-System benötigt wird. Im Vortrag werden benutzerfreundliche Funktionen präsentiert und anhand einiger Beispiele live vorgeführt, mit denen dies möglich ist. Des Weiteren wird gezeigt, wie diese Funktionen bei der Entwicklung der genannten Riemenscheibenkupplung eingesetzt wurden.

Software changes constantly and continuously. It is often beneficial to record the progressive changes made to software, so that when any problems arise, it is possible to identify the change that might have caused the problem. Also, recording these changes enables recovery of the software as it was at any point of time. A version control system is used to track modifications to software. Version control systems (VCS) display when and where a change was made. In the case of multiple developers working on the same software system, version control systems also record which developer was responsible for the change. RCS, SCCS and CVS are examples of such version control systems, and they usually have a command-line interface. The widespread use of CVS has however given rise to a host of "CVS clients", which provide a two-dimensional graphical interface to CVS. While working with a version control system in two dimensions is a definite improvement over traditional command line interfaces, it is still not sufficient to display all the necessary information in a single view. Using three dimensions to display the information from a version control system like CVS is an effective and efficient way to represent multiple attributes in a single view. There are many advantages to using a third dimension for visualizing the version history and evolution of software. A three-dimensional visualization tool has been developed to provide insights into the structure and characteristics of the history of a software system. It demonstrates the benefits of three-dimensional visualization and illustrates a framework that can be used to automatically derive information from a version control system. / Master of Information Systems

The thesis deals with teaching Mathematics through folding paper using the origami, sliceforms and paperfolding methods. Selected geometric figures and their characteristics are listed in the thesis. These geometrical figures are approximated to pictures created in a mathematical software GeoGebra. Selected figures are enriched with instructions and methods of creating the given figure out of paper. The thesis includes educational tasks. The teacher and the pupils follow the task step by step. The pupils revise the schoolwork and build up a system of basic geometrical terms while folding paper. The pupils apply gained skills and acquired terms in handouts.

Seit einigen Jahren hat sich Mathcad als universelle Mathematiksoftware an vielen Universitäten, Instituten und in Unternehmen bewährt. An der Professur Maschinenelemente der TU Chemnitz wird Mathcad derzeit u.a. bei der Entwicklung einer vollkommen neuartigen Riemenscheibenkupplung für PKW-Kältemittelverdichter eingesetzt. Hierfür wurde ein mathematisches Modell entwickelt, mit dem sich die Bauteilbelastungen sowie die dynamischen Vorgänge in der Kupplung simulieren lassen. Bei der Analyse und Optimierung solcher technischen Systeme besteht häufig der Wunsch, die Bewegung der Bauteile und die wirkenden Kräfte direkt in Mathcad dreidimensional zu visualisieren, ohne dass dafür ein CAD-System benötigt wird. Im Vortrag werden benutzerfreundliche Funktionen präsentiert und anhand einiger Beispiele live vorgeführt, mit denen dies möglich ist. Des Weiteren wird gezeigt, wie diese Funktionen bei der Entwicklung der genannten Riemenscheibenkupplung eingesetzt wurden.