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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.
201

Um terminal grafico interativo baseado na tecnologia do TV Raster

Tozzi, Clésio Luis, 1948- 15 July 2018 (has links)
Orientador : Manuel de Jesus Mendes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Campinas / Made available in DSpace on 2018-07-15T13:30:53Z (GMT). No. of bitstreams: 1 Tozzi_ClesioLuis_D.pdf: 2880248 bytes, checksum: 4e6d33c3da27b0b41911857f8b6897d3 (MD5) Previous issue date: 1979 / Resumo: O trabalho trata do desenvolvimento de um terminal gráfico interativo baseado na tecnologia do 'TV Raster', com estrutura dinâmica da 'picture memory' e conversão em tempo real do 'display file', possibilitando a rápida atualização da imagem, requisito necessário às aplicações interativas como: controle de processos, CAD, etc / Abstract: Not informed / Doutorado / Doutor em Engenharia Elétrica
202

The impact of recent high-risk coronary artery disease on major vascular complications after non-cardiac surgery / HIGH-RISK CAD & VASCULAR OUTCOMES WITH NON-CARDIAC SURGERY

Thomas, Sabu 06 1900 (has links)
Recent high-risk coronary artery disease (CAD), defined as Canadian Cardiovascular Society (CCS) class III or IV angina or acute coronary syndromes (ACS) unstable angina, is independently associated with increased mortality and morbidity following non-cardiac surgery. It remains unclear how the components of high-risk CAD, use of stents and timing of surgery after a high-risk CAD event is associated with risk. This project will address these issues and how they affect current perioperative medicine. / Thesis / Master of Science (MSc)
203

Mechanical and physical properties of three CAD/CAM glass-ceramics

Mullayousef, Hashem Ali 26 July 2022 (has links)
OBJECTIVES: To evaluate the mechanical and physical properties of three glass-ceramic CAD/CAM systems; Vita Suprinity PC (Vita ZahnFabrik), Cerrec Tessera (Dentsply-Sirona), and IPS e.max CAD (Ivoclar Vivadent). MATERIALS AND METHODS: For each material, CAD/CAM blocks were sectioned into a total of N=108 (n=12 per group) test discs with a diameter of 11.3 mm core drill and used the precision saw machine. Specimens were divided into three groups (1) glaze control, (2) polish only, and (3) ground after manufacturer glaze. Specimens were randomly assigned for the biaxial flexural strength test then each group was tested under three conditions post-treatment: (1) static, (2) thermal cycling for 5000 cycles, and (3) cyclic loading at 200,000 cycles. The biaxial flexural strength test was preformed according to ISO 6872-2015 using an Instron universal testing machine. Thermal artificial aging cycling was from 5° to 55°C, while fatigue was used for about 20% of the static failure load for 200,000 cycles. Vickers indentation was performed to test microhardness and fracture toughness. Also, surface roughness was measured for each group using a stylus contact profilometer. Additionally, surface topography and crystal microstructure analysis by SEM and crystallographic structural analysis by X-ray diffraction were done. Data were analyzed using one-way ANOVA test or least square regression (α = 0.05) and the post hoc Tukey HSD test. RESULTS: Significant differences were observed in the mean of biaxial flexural strength between the three glass-ceramics materials. The highest mean flexural strength for static was IPS e.max CAD 385.91 ± 46.23 MPa, then Vita Suprinity PC glazed 355.72 ± 72.44 MPa, followed by CEREC Tessera glazed 323.40 ± 61.01 MPa. After thermal cycling and fatiguing, there were no significant effects in flexural strength for CEREC Tessera; however, there was an increase in flexural strength for IPS e.max CAD and Vita Suprinity PC. Vickers Hardness was highest for CEREC Tessera with 7.19 ± 0.47 GPa, then Vita Suprinity PC at 7.05 ± 0.73 GPa, followed by IPS e.max CAD 5.79 ± 0.77 GPa. The fracture toughness for IPS e.max CAD was the highest with 1.97 ± 0.12 MPa.m1/2, CEREC Tessera 0.93 ± 0.05 MPa.m1/2, and Vita Suprinity PC 0.85 ± 0.08 MPa.m1/2. CONCLUSIONS: IPS e.max CAD polished outperformed Vita Suprinity PC and CEREC Tessera with respect to flexural strength under different aging conditions. In contrast, Vita Suprinity PC had the highest strength in every aging condition among the glazing group. Clinically Significant: Although all three materials might be suitable for single restorations, caution is needed when choosing material, especially as the rough surface from clinical adjustments may reduce its strength.
204

CAD2VR - Automatische Konvertierung von CAD in die Virtuelle Realität / CAD2VR - An Automated Way for Conversion from CAD to Virtual Reality

Lorenz, Mario, Spranger, Michael, Wittstock, Volker, Hoffmann, Alexander 08 May 2014 (has links) (PDF)
Produkte im Maschinenbau gewinnen durch immer weitreichendere Kundenanforderungen zunehmend an Komplexität. Davon angetrieben, werden auch die eingesetzten Softwarewerkzeuge kontinuierlich weiterentwickelt.CAD-Systeme werden beispielsweise heutzutage nicht mehr ausschließlich zur Konstruktion verwendet, sondern beinhalten meist auch weiterführende Module bspw.zur Simulation physikalischer Effekte (CAE) bis hin zur Arbeitsplanung (CAP) und werden in ganzen Softwaresuiten angeboten. Im vergangenen Jahrzehnt sind außerdem Mechanismus- und Bewegungsanalysen fester Bestandteil von CAD-Systemen geworden. Zusatzinformationen, wie bspw. Kinematikbeziehungen und / oder Animationen, die zur Verifikation der Funktionalität und Kollisionsfreiheit unabdingbar sind, können direkt in den CAD-Programen erstellt und überprüft werden. Die aktive Nutzung und Zugänglichkeit dieser CAD-Konstruktionssysteme durch konstruktionsferne Nutzergruppen ist nur bedingt durch so genannte Model-Viewer gegeben, wodurch bspw. die Fehlerbewertung (z.B. Design Review, FMEA) außerhalb der Entwicklungsabteilungen erschwert wird. Abhilfe bietet hier die Nutzung von High-EndTechniken, wie die immersive Darstellung mittels Virtual Reality (VR)-Technologie, im Prozess der Konstruktionsbewertung/Design Review. Dafür arbeiten wir mit der Chemnitzer Firma ARCsolutions GmbH an einer Lösung wie ein (teil-)automatisiert reduziertes Modell, unter Erhaltung im CAD definierter Animationen und Kinematischen Beziehungen automatisiert in die VR gebracht und dort genutzt werden kann.
205

CAD2VR - Automatische Konvertierung von CAD in die Virtuelle Realität

Lorenz, Mario, Spranger, Michael, Wittstock, Volker, Hoffmann, Alexander 08 May 2014 (has links)
Produkte im Maschinenbau gewinnen durch immer weitreichendere Kundenanforderungen zunehmend an Komplexität. Davon angetrieben, werden auch die eingesetzten Softwarewerkzeuge kontinuierlich weiterentwickelt.CAD-Systeme werden beispielsweise heutzutage nicht mehr ausschließlich zur Konstruktion verwendet, sondern beinhalten meist auch weiterführende Module bspw.zur Simulation physikalischer Effekte (CAE) bis hin zur Arbeitsplanung (CAP) und werden in ganzen Softwaresuiten angeboten. Im vergangenen Jahrzehnt sind außerdem Mechanismus- und Bewegungsanalysen fester Bestandteil von CAD-Systemen geworden. Zusatzinformationen, wie bspw. Kinematikbeziehungen und / oder Animationen, die zur Verifikation der Funktionalität und Kollisionsfreiheit unabdingbar sind, können direkt in den CAD-Programen erstellt und überprüft werden. Die aktive Nutzung und Zugänglichkeit dieser CAD-Konstruktionssysteme durch konstruktionsferne Nutzergruppen ist nur bedingt durch so genannte Model-Viewer gegeben, wodurch bspw. die Fehlerbewertung (z.B. Design Review, FMEA) außerhalb der Entwicklungsabteilungen erschwert wird. Abhilfe bietet hier die Nutzung von High-EndTechniken, wie die immersive Darstellung mittels Virtual Reality (VR)-Technologie, im Prozess der Konstruktionsbewertung/Design Review. Dafür arbeiten wir mit der Chemnitzer Firma ARCsolutions GmbH an einer Lösung wie ein (teil-)automatisiert reduziertes Modell, unter Erhaltung im CAD definierter Animationen und Kinematischen Beziehungen automatisiert in die VR gebracht und dort genutzt werden kann.
206

Berechnung und Simulation von Kurvenschrittgetrieben / Calculation and simulation of indexing cam mechanism

Heine, Andreas 07 June 2017 (has links) (PDF)
Bei CAD-Systemen mit integriertem MKS ist der Schritt zur Simulation von Kurvenschrittgetrieben vermeintlich kurz, da alle zugehörigen Bauteile inkl. der Massen und Trägheiten vorhanden sind, jedoch müssen Bewegungsprofile meist mit einer zusätzlichen Software gestaltet werden. Außerdem sind oft Änderungen an den Geometrien für ein lauffähiges Simulationsmodell notwendig und dynamische Aspekte können nur begrenzt abgebildet werden. Der Einsatz von Spezialsoftware wie MOCAD liefert schnell Ergebnisse und ermöglicht einfache Parametervariationen, wobei meist nur kinetostatische Analysekennwerte auf Grundlage analytischer Berechnungsvorschriften betrachtet werden. Dynamische Effekte und genaue Kontaktanalysen in den Kurvengelenken übersteigen meist den Funktionsumfang solcher Programme. Der Aufbau eigener Simulationsmodelle mit Hilfe von CAS-Systemen ermöglicht exakte Simulationsmodelle bei sehr hohem Programmier- und Debugg-Aufwand. Der hohe Komplexitätsgrad macht diese Tools nur für Spezialisten anwendbar.
207

BancoWeb: base de imagens mamográficas para auxílio em avaliações de esquemas CAD / Mammographic image database for CAD schemes evaluation

Matheus, Bruno Roberto Nepomuceno 22 April 2010 (has links)
Este trabalho teve como objetivo desenvolver uma base de imagens mamográficas online com acesso público para desenvolvimento, testes e avaliação comparativa de esquemas computadorizados de auxilio ao diagnóstico (CADs). A base contem imagens de vários hospitais, com grande variedade de laudos, também disponíveis na base assim como informações sobre dados clínicos (não confidenciais) dos pacientes. Uma interface detalhada foi criada para permitir o fácil acesso público, permitindo o uso de ferramentas de busca, recorte, analise estatística e inserção remota de imagens, entre outras. Testes comparativos com bases já existentes e amplamente usadas mostraram que a base desenvolvida tem quantidade e qualidade de imagens comparável ou superior as outras, além de oferecer uma quantidade de ferramentas muito maior. / This work has the objective of developing an online mamographic image database with public access for development, test and evaluation of computer-aided diagnosis (CAD). The database contains images from several hospitals, with great variety of medical reports, also available on the database together with other clinical information (not classified) from the patient. A detailed interface was developed to allow easy public access, allowing the use of tools for search, clipping, statistical analyses, remote insertion and others. Comparative test with other already existing databases shown that the presented database has quantity and quality comparable or superior to the others and offers a greater set of tools for the user.
208

BancoWeb: base de imagens mamográficas para auxílio em avaliações de esquemas CAD / Mammographic image database for CAD schemes evaluation

Bruno Roberto Nepomuceno Matheus 22 April 2010 (has links)
Este trabalho teve como objetivo desenvolver uma base de imagens mamográficas online com acesso público para desenvolvimento, testes e avaliação comparativa de esquemas computadorizados de auxilio ao diagnóstico (CADs). A base contem imagens de vários hospitais, com grande variedade de laudos, também disponíveis na base assim como informações sobre dados clínicos (não confidenciais) dos pacientes. Uma interface detalhada foi criada para permitir o fácil acesso público, permitindo o uso de ferramentas de busca, recorte, analise estatística e inserção remota de imagens, entre outras. Testes comparativos com bases já existentes e amplamente usadas mostraram que a base desenvolvida tem quantidade e qualidade de imagens comparável ou superior as outras, além de oferecer uma quantidade de ferramentas muito maior. / This work has the objective of developing an online mamographic image database with public access for development, test and evaluation of computer-aided diagnosis (CAD). The database contains images from several hospitals, with great variety of medical reports, also available on the database together with other clinical information (not classified) from the patient. A detailed interface was developed to allow easy public access, allowing the use of tools for search, clipping, statistical analyses, remote insertion and others. Comparative test with other already existing databases shown that the presented database has quantity and quality comparable or superior to the others and offers a greater set of tools for the user.
209

Analysis and Design of Virtual Reality Visualization for a Micro Electro Mechanical Systems (MEMS) CAD Tool

Li, Zhaoyi, n/a January 2005 (has links)
Since the proliferation of CAD tools, visualizations have gained importance.. They provide invaluable visual feedback at the time of design, regardless whether it is fbi civil engineering or electronic circuit design-layout. Typically dynamic visualizations are produced in a two phase process: the calculation of positions and rendering of the image and its presentation as an animated video clip. This is a slow process that is unsuitable fbr interactive CAD visualizations, because the former two require finite element analysis Faster hardware eases the problem, but does not overcome it, because the algorithms are still too slow. Our MEMS CAD project works towards methods and techniques that are suitable for interactive design, with faster methods. The purpose of this PhD thesis is to contribute to the design of an interactive virtual prototyping of Micro Electro Mechanical Systems (MEMS) This research comprises the analysis of the visualization techniques that are appropriate for these tasks and identifying the difficulties that need to be overcome to be able to offer a MEMS design engineer a meaningful and interactive CAD design environment Such a VR-CAD system is being built in our research group with many participants in the team. Two particular problems are being addressed by presenting algorithms for truthful VR visualization methods: one is for displaying objects that are different in size on the computer screen. The other is modelling unsynchronized motion dynamics, that is different objects moving simultaneously at very high and vety low speed, by proposing stroboscopic simulation to present their dynamics on the screen They require specific size scaling and time scaling and filtering. It is these issues and challenges which make the design of a MEMS CAD tool different from other CAD tools. In the thesis I present algorithms for displaying animated virtual reality for MEMS virtual prototyping in a physically truthful way by using the simulated stroboscopic illumination to filter animated images to make it possible to show unsynchronized motion.. A scaling method was used to show or hide objects which cannot be shown simultaneously on the computer screen because of their large difference in size. The visualization of objects being designed and their animations is done with much consideration of visual perception and computer capability, which is rising attention, but not too often mentioned in the visualization domain.
210

IDAPS MULTI-CAMERA STORE SEPARATION ANALYSIS USING CAD-BASED MODELING

Paulick, Michael J. 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / The Image Data Automated Processing System (IDAPS), developed by the 96th Communications Group Test and Analysis Division at Eglin AFB, uses a CAD-based image matching technique to calculate a 6DOF trajectory of a store separation event. The system has been used successfully for single camera release sequences, but needed to be extended for multi-camera releases. This is vital for bomber missions where several cameras are needed to cover a store separation event.

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