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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.

Object oriented CAE software for the exploration and design of microstructures /

Sintay, Stephen D., January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Mechanical Engineering, 2005. / Includes bibliographical references (p. 57-59).

Distortion correction for non-planar deformable projection displays through homography shaping and projected image warping

Kio, Onoise Gerald January 2016 (has links)
Video projectors have advanced from being tools for only delivering presentations on flat or planar surfaces to tools for delivering media content in such applications as augmented reality, simulated sports practice and invisible displays. With the use of non-planar surfaces for projection comes geometric and radiometric distortions. This work dwells on correcting geometric distortions occurring when images or video frames are projected onto static and deformable non-planar display surfaces. The distortion-correction process involves (i) detecting feature points from the camera images and creating a desired shape of the undistorted view through a 2D homography, (ii) transforming the feature points on the camera images to control points on the projected images, (iii) calculating Radial Basis Function (RBF) warping coefficients from the control points, and warping the projected image to obtain an undistorted image of the projection on the projection surface. Several novel aspects of this work have emerged and include (i) developing a theoretical framework that explains the cause of distortion and provides a general warping pattern to be applied to the projection, (ii) carrying out the distortion-correction process without the use of a distortion-measuring calibration image or structured light pattern, (iii) carrying out the distortioncorrection process on a projection display that deforms with time with a single uncalibrated projector and uncalibrated camera, and (iv) performing an optimisation of the distortioncorrection processes to operate in real-time. The geometric distortion correction process designed in this work has been tested for both static projection systems in which the components remain fixed in position, and dynamic projection systems in which the positions of components or shape of the display change with time. The results of these tests show that the geometric distortion-correction technique developed in this work improves the observed image geometry by as much as 31% based on normalised correlation measure. The optimisation of the distortion-correction process resulted in a 98% improvement of its speed of operation thereby demonstrating the applicability of the proposed approach to real projection systems with deformable projection displays.

Simulating Particle Packing During Powder Spreading for Selective Laser Melted Additive Manufacturing Using the Discrete Element Method in Abaqus

Ng, Priscilla 01 June 2020 (has links) (PDF)
Metal additive manufacturing allows for the rapid production of complex parts that are otherwise impractical using conventional subtractive manufacturing techniques. Applications for additive manufacturing span across a broad array of industries including aerospace, automotive, and medical, among many others. One metric of printing success is material properties, including part density. While there has been extensive research completed for the density of printed parts, there is little published work concerning powder packing density on the build plate associated with powder spreading. In this thesis, a Discrete Element Method (DEM) model was created in Abaqus to simulate the spreading behavior of particles through a single sweep of a spreader blade . Spreading behavior was investigated for three different build plate configurations: a flat build plate, a build plate with a small protruding feature, and a build plate with the same protruding feature split into quarters. For each configuration, the 2D packing behavior of the particles were analyzed during the powder spreading process. Different packing patterns seen in the 2D packing behavior were further analyzed to determine particle packing density, analogous to unit cell packing, and to predict 3D packing behavior and packing density. Additionally, particle packing density was measured following simulation using 2D image analysis to quantify powder spreading around, and interaction with, previously fused structures on the build plate. We found that the local packing fraction is measurably disrupted when particles interact with build plate features, providing insights into part density and short loading during part fabrication.

Computer aided model structuring in system design

Huang, GongWen, 1948- January 1988 (has links)
As a CAD tool, the Computer Aided Model Structuring System (call MOSTS in the following text) for model structuring in system design and system simulation has been designed and implemented. First, this MOSTS allows system design experts to create and save System Data Bases (SDBs) for model structuring in system design and simulation. Then, these SDBs can be retrieved, modified, and finally used to structure system models by design engineers. The MOSTS pursues the model structuring process in such a way that the model structure having the best performance (according to the expert's knowledge and the design engineer's design criteria) will be generated first, and then the second best model, the third best model, and so on.

Computer integration of the electrical discharge machining process

Wong, Ming-ho, Horatio., 黃明浩. January 2004 (has links)
published_or_final_version / abstract / toc / Mechanical Engineering / Master / Master of Philosophy

Optimisation of an operating policy for variable speed pumps using genetic algorithms /

Eusuff, M. Muzaffar. January 1995 (has links) (PDF)
Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1995. / Undertaken in conjunction with JUMP (Joint Universities Masters Programme in Hydrology and Water Resources). Bibliography: leaves 76-83.

Image-based boundary element computation of three-dimensional potential problems

Zhang, Hui, January 2008 (has links) (PDF)
Thesis (M.S. in mechanical engineering)--Washington State University, August 2008. / Includes bibliographical references (p. 64-66).

Classification of research and applications in feature modeling and computer aided process planning /

Kolli, Sam. January 2004 (has links)
Thesis (M.S.)--Ohio University, November, 2004. / Includes bibliographical references (p. 93-108)

A multiple-model repository with manipulation and analysis tools for process engineering /

McGahey, Steven Lewis. January 1900 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

A computer-assisted qualitative data analysis framework for the engineering management domain /

Saeedi, Amirali. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 97-103). Also available on the World Wide Web.

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