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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.
91

A B-spline geometric modeling methodology for free surface simulation

Nandihalli, Sunil S. January 2004 (has links)
Thesis (M.S.)--Mississippi State University. Department of Computational Engineering. / Title from title screen. Includes bibliographical references.
92

Sketch based 3D freeform object modeling with non-manifold data structure /

Wang, Changling. January 2002 (has links)
Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 143-152). Also available in electronic version. Access restricted to campus users.
93

CSG based automatic mesh generation using multiple element types /

Hall, Richard H. January 1993 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaves 151-156).
94

A volumetric sculpting based approach for modeling multi-scale domains

Karlapalem, Lalit Chandra Sekhar, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
95

Atividades investigativas para o ensino de óptica geométrica

Borrajo, Thiago Balacó January 2017 (has links)
BORRAJO, T. B. Atividades investigativas para o ensino de óptica geométrica. 2017.117 f. Dissertação (Mestrado Nacional Profissional em Ensino de Física) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2017. / Submitted by francisco lima (admir@ufc.br) on 2017-06-21T18:09:56Z No. of bitstreams: 1 2017_dis_tbborrajo.pdf: 2234935 bytes, checksum: 28fb00441f75e93f7465f2b7b75ff5ed (MD5) / Approved for entry into archive by Giordana Silva (giordana.nascimento@gmail.com) on 2017-06-23T15:28:55Z (GMT) No. of bitstreams: 1 2017_dis_tbborrajo.pdf: 2234935 bytes, checksum: 28fb00441f75e93f7465f2b7b75ff5ed (MD5) / Made available in DSpace on 2017-06-23T15:28:56Z (GMT). No. of bitstreams: 1 2017_dis_tbborrajo.pdf: 2234935 bytes, checksum: 28fb00441f75e93f7465f2b7b75ff5ed (MD5) Previous issue date: 2017 / In the face of a scene of dissatisfaction and indifference in the process of teaching/learning of science in basic education, we present a proposal for teaching some fundamentals topics of geometrical optics, based on investigative activities that require reflection and reasoning. In it, the students are divided into groups and they need to discuss about ideas, make hypotheses and find ways for prove them. At the end of each class, the group conclusions are confronted with formal knowledge. Making it possible to analyze discrepancies and concordances with the know theory. The methodology is based on the concepts of active learning, sociointeractionism and inquiry based learning. The main focus of the proposal is increase student interest, make him more receptive to new knowledges by problematization and discussion with colleagues and teacher. With this method, it is possible to transform student into an agent in his own process of learning, developing his skills and capabilities in a science education process. / Diante de um cenário de insatisfação e desinteresse no processo de ensino/aprendizagem de ciências na educação básica, apresentamos uma proposta para o ensino de alguns tópicos fundamentais de óptica geométrica, baseada em atividades investigativas que exigem reflexão e raciocínio. Nela, os estudantes são divididos em grupos e precisam debater ideias, construir hipóteses e encontrar meios para comprová-las. Ao final de cada aula, as conclusões dos grupos são confrontadas com o conhecimento formal, possibilitando a análise de discordâncias e concordâncias com a teoria já estabelecida. A metodologia é baseada nos conceitos de aprendizagem ativa, sociointeracionismo e ensino por investigação. O grande foco da proposta é despertar o interesse do aluno, torná-lo mais receptivo aos novos conhecimentos através da problematização e do debate com os colegas e com o professor. A partir de entrevistas com os alunos, observação da sala durante as práticas e análise de relatórios elaborados pelos próprios estudantes, foi possível constatar que eles conseguiram desenvolver, efetivamente, uma atitude científica ao longo das investigações. Com esse método, é possível fazer do estudante um agente no seu próprio processo de aprendizagem, desenvolvendo suas habilidades e capacidades em um processo de educação científica.
96

Métodos geométricos para a avaliação de sistemas ópticos centrados / Geometrical methods for evaluation of opticals centered systems.

Jorge Honel 14 February 1991 (has links)
Três métodos geométricos de traçado de raios são desenvolvidos e aplicados num programa de avaliação de sistema ópticos para microcomputadores padrão IBM-PC. O primeiro método corresponde ao traçado paraxial construído a partir do Invariante de Abbe; o segundo método corresponde ao traçado meridional proposto por Rudolf Kingslake; e o terceiro método corresponde ao traçado espacial proposto por Hainz Haferkorn e Volker Tautz. Dentro do programa estão incluídas algumas das representações das aberrações ópticas que caracterizam um sistema óptico centrado. / Three methods of ray tracing are development for use on IBM PC/XT personal computer. The first method is a paraxial ray tracing derived from the invariant Abbe; the second is a meridional ray tracing proposed by Rudolf Kingslake; and the third is a skew ray tracing proposed by Heinz Haferkorn and Volker Tautz . Based on these three methods some optical aberrations are employed to exemplify an optical centered system.
97

Diffraction and geometrical optical transfer functions: calculation time comparison

Díaz, José Antonio, Mahajan, Virendra N. 23 August 2017 (has links)
In a recent paper, we compared the diffraction and geometrical optical transfer functions (OTFs) of an optical imaging system, and showed that the GOTF approximates the DOTF within 10% when a primary aberration is about two waves or larger [Appl. Opt., 55, 3241-3250 (2016)]. In this paper, we determine and compare the times to calculate the DOTF by autocorrelation or digital autocorrelation of the pupil function, and by a Fourier transform (FT) of the point-spread function (PSF); and the GOTF by a FT of the geometrical PSF and its approximation, the spot diagram. Our starting point for calculating the DOTF is the wave aberrations of the system in its pupil plane, and the ray aberrations in the image plane for the GOTF. The numerical results for primary aberrations and a typical imaging system show that the direct integrations are slow, but the calculation of the DOTF by a FT of the PSF is generally faster than the GOTF calculation by a FT of the spot diagram.
98

Geometrical error calibration in reflective surface testing based on reverse Hartmann test

Wang, Daodang, Gong, Zhidong, Xu, Ping, Liang, Rongguang, Kong, Ming, Zhao, Jun, Wang, Chao, Mo, Linhai, Mo, Shuhui 23 August 2017 (has links)
In the fringe-illumination deflectometry based on reverse-Hartmann-test configuration, ray tracing of the modeled testing system is performed to reconstruct the test surface error. Careful calibration of system geometry is required to achieve high testing accuracy. To realize the high-precision surface testing with reverse Hartmann test, a computer-aided geometrical error calibration method is proposed. The aberrations corresponding to various geometrical errors are studied. With the aberration weights for various geometrical errors, the computer-aided optimization of system geometry with iterative ray tracing is carried out to calibration the geometrical error, and the accuracy in the order of sub-nanometer is achieved.
99

3D visualization of optical ray aberration and its broadcasting to smartphones by ray aberration generator

Hellman, Brandon, Bosset, Erica, Ender, Luke, Jafari, Naveed, McCann, Phillip, Nguyen, Chris, Summitt, Chris, Wang, Sunglin, Takashima, Yuzuru 27 November 2017 (has links)
The ray formalism is critical to understanding light propagation, yet current pedagogy relies on inadequate 2D representations. We present a system in which real light rays are visualized through an optical system by using a collimated laser bundle of light and a fog chamber. Implementation for remote and immersive access is enabled by leveraging a commercially available 3D viewer and gesture-based remote controlling of the tool via bi-directional communication over the Internet.
100

A study in geometric construction

McClain, Nichola Sue 01 January 1998 (has links)
No description available.

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