Dissertations / Theses: 'CAA (Computer system)'

1

Virk, Gurmej Singh. "A computer-aided learning and design system for control engineering." Thesis, University of Sheffield, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364270.

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Wong, Francis Seung Yin. "Case-based reasoning for computer-aided inspection process planning /." access full-text access abstract and table of contents, 2005. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-meem-b19887656a.pdf.

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Thesis (Ph. D.)--City University of Hong Kong, 2005.
"Submitted to Department of Manufacturing Engineering and Engineering Management in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 164-175).

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Moore, Robert Keith. "Computer aided programming of a CNC lathe." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25123.

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A software package and associated hardware have been developed which gives users of the ORAC CNC Training Lathe an easier and faster method of manufacturing on the lathe. The package, entitled ORACAP, uses the computing power of a mini-mainframe computer, a VAX 11/750, to assist in part design, program generation, program optimization, and program proving for the ORAC Lathe. The package is designed for users unfamiliar with computers such as students in an educational institute or workers in a production facility and uses command procedures to simplify the preparation and execution of the modules of the package. In addition to providing users with a valuable tool for manufacturing, ORACAP also gives users insight into the Computer Aided Design and Computer Aided Manufacturing methods used in industry, that is, it demonstrates the methods which allow production of a part from a very concise description of its geometry. Finally, ORACAP demonstrates the production advantages of a CAD/CAM system over conventional manufacturing methods for small to medium size batch production.
Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate

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Ghatpande, Puja Sudhakar. "Study of fixturing accessibilities in computer-aided fixture design." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-080808-195905/.

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Kwong, Kin-wa. "Computer-aided parting line and parting surface generation in mould design /." [Hong Kong : University of Hong Kong], 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1341804X.

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Sridaran, S. "Off-line robot vision system programming using a computer aided design system." Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54373.

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Robots with vision capability have been taught to recognize unknown objects by comparing their shape features with those of known objects, which are stored in the vision system as a knowledge base. Traditionally, this knowledge base is created by showing the robot the set of objects that it is likely to come across. This is done with the vision system to be used and must be done in an online mode. An approach to teach the robot in an off-line mode by integrating the robot vision system and an off-line graphic system, has been developed in this research. Instead of showing the objects that the robot is likely to come across, graphic models of the objects were created in an off-line graphic system and a FORTRAN program that processes the models to extract their shape parameters was developed. These shape parameters were passed to the vision system. A program to process an unknown object placed in front of the vision system was developed to extract its shape parameters. A program that compares the parameters of the unknown object with those of the known models was also developed. The vision system was calibrated to measure the pixel dimensions in inches. In the vision system, shape parameters of the objects were found to vary with different orientations. The range of variation for each parameter was established and this was taken into consideration in the parameter comparison program.
Master of Science

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Choi, Young Gu. "An integrated computer simulation system to evaluate surface integrity in end milling /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9717175.

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Bedingfield, Ralph Andrew. "Development of CAE system for switched motor drive systems." Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10312009-020029/.

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Sturnick, Gerald R. "Integration of computer-aided design techniques into the mechanical product development process /." Online version of thesis, 1989. http://hdl.handle.net/1850/10477.

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鄺建華 and Kin-wa Kwong. "Computer-aided parting line and parting surface generation in mould design." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31233119.

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Baker, Tyson J. "Attribution Standardization for Integrated Concurrent Engineering." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd873.pdf.

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12

Yang, Yihong. "Integrated quality control planning in computer-aided manufacturing planning." Worcester, Mass. : Worcester Polytechnic Institute, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-041607-164054/.

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Thesis (Ph. D.)--Worcester Polytechnic Institute.
Keywords: In-process inspection; tolerance assignment; tolerance stack-up analysis; quality control planning. Includes bibliographical references (leaves 136-148).

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13

Xue, Sukui, and 薛苏葵. "Voice-enabled CAD system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45461405.

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Kohareswaran, Naganandhini. "Design and implementation of Sketcher user interface for a geometric constraint solver /." [Gainesville, Fla.] : University of Florida, 2002. http://purl.fcla.edu/fcla/etd/UFE0000556.

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Jain, Vikesh. "A platform independent process data exchange mechanism between Java applications and computer aided manufacturing systems." Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1081784819.

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Chan, Chi-fung. "Computer-aided design and manufacturing of tactile maps." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B37895722.

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Chan, Chi-fung, and 陳智鋒. "Computer-aided design and manufacturing of tactile maps." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B37895722.

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Deal, Julia L. "Assessment of classical database models for representing solids /." Online version of thesis, 1987. http://hdl.handle.net/1850/8804.

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Li, Dong. "Physics- and engineering knowledge-based geometry repair system for robust parametric CAD geometries." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348924/.

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In modern multi-objective design optimisation, an effective geometry engine is becoming an essential tool and its performance has a significant impact on the entire process. Building a parametric geometry requires difficult compromises between the conflicting goals of robustness and flexibility. The work presents a solution for improving the robustness of parametric geometry models by capturing and modelling relative engineering knowledge into a surrogate model, and deploying it automatically for the search of a more robust design alternative while keeping the original design intent. Design engineers are given the opportunity to choose from a list of optimised designs to balance the robustness of the geometry and the original design intent. The prototype system is firstly tested on a 2D intake design repair example and shows the potential to reduce the reliance on human design experts in the conceptual design phase and improve the stability of the optimisation cycle. It also helps speed up the design process by reducing the time and computational power that could be wasted on flawed geometries or frequent human interferences. A case-study of the proposed repair system based on the design and analysis of a three-dimensional parametric turbine blade model has been set up. An automatic analysis workflow is set up and the results are summarised for setting up a repair database based on surrogate training methods. Positive repair results have been achieved and an automatic repair cycle for the blade model is being set up and tested. The proposed physics and engineering knowledge based geometry repair system for robust parametric geometries proves an effective tool for ensuring automation robustness and design flexibility.

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Rodriguez-Tellez, J. "Chameleon : An integrated desktop-based computer-aided design workstation." Thesis, University of Bradford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374925.

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Tamburini, Diego Romano. "The analyzable product model representation to support design-analysis integration." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17106.

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Young, Jared M. "Nesting automated design modules in an interconnected framework /." Diss., CLICK HERE for online access, 2005. http://contentdm.lib.byu.edu/ETD/image/etd973.pdf.

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Gandhi, Ashit R. "A CAD/CAM interface for computer-aided design of cams." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/41555.

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The purpose of this thesis is to provide a complete package for the design and three dimensional modeling display of cams.

The software produced as a part of this work will operate as a module of CADAM to produce cam designs and enter the resulting cam as a CAD model and produce the graphical display of the cam.

In addition to the introductory material, this thesis is divided into four sections. The section on the graphics packages used in this thesis includes a brief history and capabilities of each of the packages. The second section details the procedure to be adopted in order to design a cam. The next section details ANICAM, the program that has been developed to incorporate the design and display procedure. The fourth section of this thesis contains recommendations for further work in this area.

The theoretical work in this project is a combination of original derivations and applications of the theory in the design literature.

Master of Science

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24

Truong, Hai The 1962. "Management framework of automotive full service supplier in computer aided engineering (CAE)." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/91742.

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Kalta, Mohamad. "Integration of computer aided process planning with a commercial CAD system." Thesis, University of Manchester, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303121.

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Grieshaber, Michele Marie. "A computer-aided software engineering toolkit for the integration of CAD/CAM application software in a network environment." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37875.

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Much progress has been made in recent years in the development of Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) tools for engineering design, analysis, and manufacturing. Unfortunately, most of these CAD/CAM applications were constructed independently and without standardization. In essence, they automate a single aspect of design, analysis, or manufacturing and cannot be combined to form a cohesive environment, since integration among applications was not addressed during the design phase of CAD/CAM application software creation. In view of this problem, a novel approach is suggested for software integration of applications in a network environment. The distributed integration solution described in this dissertation employs a new "integration client/server" relationship, where the integration server is the core of the system, providing functions to translate or transform data between applications. The integration client consists of an interface with the server, a CAD/CAM application, and a user interface with the integrated system called the GRIM (GRaphical Interface Manager). There is only one integration server in the system, but there may be an unlimited number of clients. The solution created for distributed integration is implemented in a Computer-Aided Software Engineering (CASE) workbench, geared specifically toward the generation of integration systems. This workbench is known as the CAD/CAM CASE Workbench, and includes an integration solution as well as standard CASE tools. The integration solution contains several tools which will aid a system designer in generating integration systems for CAD/CAM applications. Included is the distributed integration solution described in this dissertation. The distributed integration solution is designed to facilitate the semi-automatic generation of an integration system. It consists of an integration server at the center of the integration system which manages the exchange of data among the integration clients. The integration clients are the CAD/CAM applications in the context of the integration system. To use the distributed integration solution, the integration system designer will customize portions of the structure charts, data dictionary, and module specifications contained in the workbench according to the needs of the applications programs and generate C-source code defining the integration system. Using the distributed integration solution, the user will be able to effect data requests for applications, using the GRIM to interact with the system. All data exchanges are request driven. In addition to the distributed integration solution, this research includes a prototype integrated system which allows data to be requested from one application, and translated to a second for display and manipulation. The prototype was tested in a distributed environment and the results are described.
Ph. D.

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27

Thibault, William Charles. "Application of binary space partitioning trees to geometric modeling and ray-tracing." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/9142.

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Rangan, Ravi M. "Engineering data integration in a discrete part design and manufacturing environment." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/18837.

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Singh, Balraj. "A parametrized CAD tool for VHDL model development with X Windows." Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03242009-040819/.

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30

Gorton, Ian. "Behavioural specification and simulation of minimum configuration computer systems." Thesis, Sheffield Hallam University, 1988. http://shura.shu.ac.uk/19708/.

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The ultimate goal of Computer-Aided Design research in the area of digital circuits is the automatic synthesis of a complete solution from a behavioural specification. This thesis describes an attempt to attain this ideal in the more limited realm of designing single-board control systems, constructed from general-purpose microprocessor components. The difficulties currently encountered in designing and implementing microprocessor control systems are outlined, and the architecture of an integrated, knowledge-based design system is proposed as a method of overcoming these difficulties. The design system encompasses both behavioural and structural design functions. However, only the tools and techniques required to fulfil the behavioural design functions are considered in detail in this project. A review of previous work in the field of automated digital circuit design and software and hardware specification languages is presented. The major features of a novel language for specifying and simulating control system behaviour are then described, together with an intermediate design description notation, which facilitates the generation of microprocessor assembly language code directly from behavioural specifications. The design and implementation of a fast, generalised microprocessor simulation facility constructed from transputers is discussed, and its performance potential analysed. The simulation facility enables the complete design for a given application to be tested, before any actual hardware construction takes place. Finally, an evaluation of the behavioural specification, synthesis and simulation techniques developed in this project is presented, and the benefits perceived from adopting such techniques are summarised. Issues concerning the integration of these techniques with the knowledge-based structural design tools are also dealt with, and suggestions for further developments and enhancements are identified.

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31

Zhao, Yiqun. "Computer aided design of nonlinear control systems having general structure." Thesis, University of Hull, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382048.

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Dhamija, Dinesh. "Macintosh - Bridgeport communications CAD/CAM." Ohio : Ohio University, 1988. http://www.ohiolink.edu/etd/view.cgi?ohiou1182784285.

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Trafford, David B. "An investigation into methods for the evolutionary development of computer-aided design systems." Thesis, Kingston University, 1985. http://eprints.kingston.ac.uk/20502/.

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A basic requirement of all CAD systems, is that the facilities offered remain relevant to the current needs of users. A characteristic of CAD system users is that their requirements continually change or, to be more accurate, evolve, as their understanding of the design problem and available technology develops. This trait is exemplified by their inability to articulate requirements, both immediate and future with any degree of confidence. Industrial experience of using the traditional methods for developing information systems, which are based upon the Linear Life Cycle (LLC) concept, has proven to be unsuitable for CAD applications. Its failure results from the premise that users' requirements may be accurately stated at the start of the cycle and will not change with time. The need for a new development strategy which supports the evolving requirements of CAD system users is therefore evident. This research resulted in the formulation of such a development strategy. It is based upon an evolutionary approach to system development in which the users' requirements are initially satisfied by the design and implementation of a pilot sub-system which in turn forms the basis for evolution by, its incremental modification and/or extension. The success of this approach principally lies in the ability to modify the software as required with tbe minimum of resources. A major factor determining the degree to which a system may be modified was identified to beits software configuration. A number of design techniques were proposed which contributed to highly flexible configurations, principally through the criteria for functional partitioning, decoupling of functional modules from data storage and the method of organising the data. A new type of data structure was also devised which enabled new data entities and relationships to be added with no modification to the software structure. The development methods resulting from this research were extensively validated during the design and implementation of a large scale industrial CAD system.

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Grieve, M. D. "Self-adaptive methods for computer-aided design of electromagnetic systems." Thesis, University of Aberdeen, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382136.

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Cedorge, Thomas. "Surface roughness and draft angle effects on stereolithography molds." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/18199.

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Gandhi, Ashit R. "Feature-based geometric modeling using B-spline surfaces and a natural language approach." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54359.

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Traditionally, design geometries are represented using orthographic views which require a human being to interpret them and recognize geometric features to evaluate the design. Solid modeling systems have made the task somewhat easier, but they often require tedious and complex operations using simple geometric primitives. This has led to investigation of modeling systems which allow the creation of assemblies the way engineers conceive them - as features. To be able to efficiently describe models in terms of features, a rich set of feature descriptors are necessary. An exhaustive study of English words describing form, shape, feature, shape altering transformations and surface conditions was done to establish a wide vocabulary for feature based description. Classification based on topology and form was done and prototype constraint relations were implemented to differentiate between some features. A feature is created from a topological group by computing points and interpolating them with uniform rational B-spline patches. Control points needed to compute the patches are computed from the interpolation points by an inverse relation. A designer-oriented modeling language, based on simple English syntax, was devised to specify procedures to be executed by the modeler in order to create features using minimal user input.
Ph. D.

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37

Jayaram, Sankar. "CADMADE, an approach towards a device-independent standard for CAD/CAM software development." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54204.

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Every year thousands of specialized CAD/CAM applications programs are developed to meet the needs of industry, education and research. The international 3-D graphics standard, PHIGS, has proven to be very useful in the creation of custom CAD/CAM software. Although PHIGS+ promises to deliver some geometric modeling procedures, not nearly enough is being done to support the writing of CAD/CAM software. CAD/CAM applications programmers should have available a standardized high level applications programming environment which supports the creation of device-independent and portable design and manufacturing software. In this dissertation, one approach towards the establishment of a CAD/CAM programming standard has been presented. This programming environment is called CADMADE - Computer-Aided Design and Manufacturing Applications Development Environment. CADMADE includes not only graphics programming support, but also high level procedures to support the creation of geometric modeling, mechanical design, manufacturing, expert systems and user interface software. The requirements of CADMADE have been created. CADMADE consists of five environments: the User Interface Environment (UIE), the Design and Modeling Environment (DME), the Virtual Manufacturing Environment (VME), the Expert Consultation Environment (ECE) and the PHIGS+ Environment. The User Interface Environment has been designed in great detail. A prototype of the User Interface Environment has been created using PHIGS. Examples of applications programs which use the prototype User Interface Environment are presented. The Design and Modeling Environment has also been designed. A new set of logical input/output devices has been created for the Design and Modeling Environment. The requirements of the Expert Consultation Environment and some new concepts in expert system consultation are discussed.
Ph. D.

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38

Cournoyer, Richard John. "The Application of Parametric Software into the Undergraduate Computer-Aided Manufacturing Environment." Digital WPI, 1999. https://digitalcommons.wpi.edu/etd-theses/1078.

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"This thesis presents an in depth study of Pro/Engineer's manufacturing module and its application into the Computer-Aided Manufacturing (CAM) undergraduate education environment. Mechanical Engineering has a lot to gain by incorporating computers into the undergraduate curriculum in comparison to only the traditional classroom surroundings. Today, complex problems can be solved in mere seconds thanks to the power and speed of current computers. Likewise within today's manufacturing sector, numerical controlled (NC) machines are no longer programmed manually. In today's globally competitive manufacturing environment, integrated systems such as CAD/CAM help reduce the ever-shrinking time to market. This thesis contains the background as well as the curriculum material necessary to teach undergraduate students CAM using Pro/Engineer's manufacturing module. The curriculum material starts with the tutorials to teach and reinforce Pro/Engineer basic sketcher skills, which are necessary background information. Followed with in-depth click tutorials to teach the manufacturing module for 2 axes turning, and 3 axes hole drilling and milling. It also includes the necessary lab manuals that reinforce the class lecture material, an electronic manufacturing exam, and the students' evaluations from 2 terms when the CAM course (ME3820) was offered."

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Feijo, Bruno. "Fundamental steps towards an intelligent CAD system in structural steel." Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47057.

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Yao, Suqin. "Computer-Aided Manufacturing Planning (CAMP)of Mass Customization for Non-rotational Part Production." Link to electronic dissertation, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-1216103-153523/.

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Dissertation (Ph.D.) -- Worcester Polytechnic Institute.
Keywords: Computer aided manufacturing planning; Object-oriented systems analysis (OSA); Feature; manufacturing resource capability; setup planning; multi-part fixture Includes bibliographical references (p.146-154).

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Cheung, Cho-lam Vincent, and 張祖霖. "The application of CAD system in urban design." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31257665.

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Scott, Peter J. "Towards an intelligent authoring system." Thesis, University of Sheffield, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337237.

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Rivers, Mark G. "Object-oriented data management for digital electronics CAD systems." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386801.

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Narayanan, Parasuram. "An object-oriented framework for the creation of customized expert system for CAD." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06302009-040418/.

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Lim, Alan Wui Tze. "Exploring vision mechanisms for constructing a CAD reconstruction and recognition system." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336322.

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Kelsey, Matthew Douglas. "THE DEVELOPMENT AND EVALUATION OF TECHNIQUES FOR USE IN MAMMOGRAPHIC SCREENING COMPUTER AIDED DETECTION SYSTEMS." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/dissertations/331.

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The material presented in this dissertation details techniques developed to aid in the detection of a specific type of cancerous lesion visible on screening mammography images. These spiculated lesions most often appear as centrally bright objects with semi-defined borders. Furthermore, lesion margins are composed of indicative spiculations or fine tendrils projecting outward from the mass center. The techniques developed here to identify these characteristics and detect these objects are intended to operate as a processing pipeline. The first group of these processing stages is responsible for converting raw mammogram pixel data into localized and described objects. A second group of processing stages categorizes these objects by manipulating their descriptors and evaluating their meaning. At the conclusion of this processing pipeline, it is intended that image pixels which designate a cancerous mass will be highlighted and presented to a human operator as an aid in the early detection of breast cancers. The initial problem of object localization is addressed with breast tissue region extraction followed by a specialized spot detection algorithm. Tissue region extraction is accomplished using specific dataset image domain knowledge along with a simple threshold segmentation algorithm. Once this image area of interest is specified, contained objects of interest are identified using Iterative Disjoint Region Detection (IDRD). This specialized procedure utilizes iterative threshold segmentation to produce a three dimensional map of each image's pixel space. In this map, two dimensions directly correspond to the spatial dimension of the original image while the third corresponds to the normalized gray level of individual pixels. Traversing this map from the brightest pixel values to the darkest yields object "peaks", which are taken to be seeds of visible objects. Seeds are further processed at each successive threshold iteration by considering the effects of combining adjacent designations. This seeding process effectively detected all objects of interest with at least one seed. Because it was designed as a general purpose spot detection algorithm, many non-cancerous locally bright objects were detected as well. These other detections accounted for a wide majority of the seeds noted in each mammogram with approximately thirty to sixty seeds identified in most dataset images. A complementary task to object localization is the identification of each object's visible border and pixel area. This process is accomplished by a customized general purpose region growing routine, commonly known as pixel aggregation. During this procedure, spatially attached pixels are considered for inclusion with a prototype region defined by the region's corresponding seed object. Candidate pixels must meet a gray tone similarity criteria with our inclusion interval computed using the template region's average gray value. This process is supplemented by a leakage detection mechanism which serves to detect and recover from over segmentation of non-target objects in the image space. Leakage detection operates by tracking pixel aggregation rates for each iteration of the region growing process. A leakage is said to occur if the aggregation rate profile exhibits telltale characteristics of object border crossing followed by segmentation of an adjacent object. Once objects have been localized and their member pixels identified through the proceeding procedures it is the purpose of the next system stage to describe these objects using various measured features. The extraction of these measurements is the final step in transforming objects from image based visual depictions to abstract numerical representations. This new representation facilitates the forthcoming statistical treatment of these objects. Feature extraction is accomplished using a number of general use as well as special purpose measurements which quantify characteristics such as object shape, texture, and parent seed evolution. A total of forty-one feature measurements are extracted in order to insure full representation of detected objects and to facilitate accurate object class membership. In the next section of work, we seek to categorize these objects which have just been detected, segmented and described using feature measurements. The roll of a statistical classifier in accomplishing this is presented along with specifics as to the type of classifier used here. The use of a Bayes classifier is discussed and rationalized along with the development of the parametric Gaussian model for class conditional density estimation. Along with classifier development, a treatment of system performance evaluation is given. The Free-response Receiver Operating Characteristic (FROC) is described as an appropriate method by which to evaluate observer studies. This method suits the described CAD system, as a certain number of false positive detections are seen as acceptable and the system goal is to maximize mass sensitivity within these bounds. Our CAD system supplements the traditional classifier components by considering the effects of advanced feature vector manipulation. In total, five distinct models are developed including various iterations of feature selection and feature vector transformation. The Select model is presented as a benchmark and consists of a cumulative performance based feature selection step. The PCT Select and the DCT Select models are used to generate new feature vectors from the original measured set as linear combinations of its elements. PCT and DCT indicate the vector transformation model, Principle Components Transform and Discrete Cosine Transform respectively. Once transformed, the resultant feature vectors are processed with the same Select feature selection routine as in the benchmark model. The goal with both Transform-Select feature manipulation models is to generate a compact feature set which retains all of the necessary discriminatory information from measured features while rejecting measured characteristics which do not support accurate object classification. Two related models are also considered which measure the impact of implementing feature pre-selection on the PCT Select and the DCT Select models. The aptly named Select PCT Select and the Select DCT Select models seek to remove measured features which contain no discriminatory information from the pool of transformed data. System performance results for the five selection models are then compared to discern the contribution of each in the detection of cancerous masses. A complete analysis of the feature selection and transformation models show that while the benchmark Select model performs reasonably, considerable performance improvements are possible using feature vector manipulation methods. Performance metrics are generated with the use of a Free-response Receiver Operating Characteristic (FROC) plot. This method compares the mass detection sensitivity possible to the number of false positive detections per mammogram evaluated. Feature selection and classifier training is performed to maximized this sensitivity at a particular operating point, 4 FPpI. This point is taken as within the range of acceptable false indications in a typical clinical setting. Overall, the best system performance is seen with the use of the Select DCT Select feature model (84.51% sensitivity at 4 FPpI). This corresponds to a net increase of eighteen additional mass detections with the same amount of false positive indications and an increased mass sensitivity of 84.51% from 71.53% using the benchmark Select model. The other selection model using a pre-selection stage, Select PCT Select, reports similar performance results. This model is used to detect 118 true positive masses, sixteen more then the Select model and just two less then the Select DCT Select model. Both of the other system configurations, PCT Select and DCT Select, were able to detect 109 true masses in the data set. This corresponds to a 76.76% mass sensitivity at 4 FPpI. Although not as impressive as results generated with the pre-selection models, this is still a 5.23% improvement in mass sensitivity in comparison to the benchmark.

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47

Morad, Ayman Ahmed. "Geometric-based reasoning system for project planning utilizing AI and CAD technologies." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-06062008-172127/.

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48

Zhao, Yue. "The integration of CAD and a knowledge based cutting tools selection system." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267191.

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49

Smith, Kenneth S. "CAD simulation of drive converters on isolated marine power systems." Thesis, University of Aberdeen, 1992. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU040411.

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Abstract:

Power electronic converters are being increasingly used on isolated marine power systems, to provide variable speed control of electric motors. As the rating of these drive converters increases, the converter load becomes a significant part of the total system load. Traditional methods for calculating the performance characristics, which assume the presence of an infinite busbar on the system, are not appropriate for such systems. The intercoupling which exists between system components such as synchronous generators, converters, and the drive motor must be included in the calculation. In this thesis, a commercially available software simulator Saber, is used to model a complete electrical cycloconverter propulsion drive, of the type which may be used for future Royal Navy frigates. This model includes the synchronous generators, cycloconverters, and induction motor drives. The simulation is performed in the time domain, which ensures that the intercoupling present between system components is preserved. The simulation is not restricted to one converter configuration, and has been used to investigate the relative merits of a number of possible converter connections. This method can be used to study drive performance under unbalanced conditions as well as for normal balanced operation. There is no perceived limit to the size, or complexity, of the converter systems which can be studied using this method. The only cost would be increased computer run times.

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50

Payne, Stephen Richard. "A CAD-interactive software package for the synthesis of planar disk cams." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-09042008-063021/.

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Dissertations / Theses on the topic 'CAA (Computer system)'

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