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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.
1

Tree manipulation algorithms and the design processing software

Wilson, A. D. January 1986 (has links)
No description available.
2

A Study For The Development Of Seismic Design Specifications For Coastal Structures

Gozpinar, Erdem 01 January 2003 (has links) (PDF)
An evolving design philosophy for port structures in many seismically active regions reflects the observations that: -The deformations in ground and foundation soils and the corresponding structural deformation and stress states are key design parameters. -Conventional limit equilibrium-based methods are not well suited to evaluating these parameters. -Some residual deformation may be acceptable. Performance-based design is an emerging methodology whose goal is to overcome the limitations present in conventional seismic design. Conventional building code seismic design is based on providing capacity to resist a design seismic force, but it does not provide information on the performance of structure when the limit of the force-balance is exceeded. If we demand that limit equilibrium not be exceeded for the relatively high intensity ground motions associated with a rare seismic event, the construction cost will most likely be too high. If forcebalance design is based on amore frequent seismic event, then it is difficult to estimate the seismic performance of the structure when subjected to ground motions that are greater than those used in design. In this thesis a case study will be carried out on a typical port structure to show the performance evolution aspects and its comparison with damage criteria and performance grade in performance-based methodology.
3

Design methodology for modeling a microcontroller

Southard, Phillip D. January 2000 (has links)
No description available.
4

Empirical comparisons of system analysis modeling techniques

Gemino, Andrew C. 11 1900 (has links)
The development of information systems consumes an increasing share of economic resources. Over a trillion dollars worldwide is invested in information technology annually, and this investment is growing over $100 billion a year. This investment occurs despite failure rates for large information system development projects that are estimated as high as 75%. The large investment and high failure rates combine to create the potential for significant impact from information system development practices that are able to address these failure rates. Researchers, over the past thirty years, have studied factors that drive these high failure rates. One of the factors repeatedly mentioned in practitioner surveys is the importance of accurate communication in the "upstream" analysis and planning stage of a project. System development professionals are aided in their upstream planning through the use of information system development methods (ISDM's). ISDM's are modeling tools and techniques that are capable of representing information about an information system. Many alternative system analysis modeling techniques have been developed, yet few empirical comparisons of the alternative techniques have been completed. The lack of comparative empirical data has contributed to a proliferation of modeling methods and increased the confusion surrounding the adoption of system analysis methods by system development professionals and teachers. This study addresses the issue of empirical comparison of system analysis modeling techniques. A new instrument and empirical method is proposed for developing a comparison of the level of "understanding" that a participant is able to create by viewing a description of a particular domain. The level of "understanding" is addressed using three measures: comprehension, problem solving, and text reconstruction. The new measures of "problem solving", suggested by Mayer in the field of Education Psychology, and "text reconstruction" or "Cloze", suggested by Taylor in the field of Communications, extend empirical instruments previously used by system analysis researchers. To test the efficacy of the proposed instrument and method, two empirical studies were developed in this thesis. The first study used the new instrument to compare three development methods "grammars: Text descriptions; Structured Analysis (using Data Flow Diagrams and Entity Relationship Diagrams); and Object Oriented Diagrams. The study was labeled an "Intergrammar" comparison, as three grammars representing three fundamental approaches to developing an analysis model were compared. Two propositions, in regards to the intergrammar study, were tested. The first suggested that viewing descriptions created with diagrams would lead to a higher level of understanding than viewing a description based solely on text. This hypothesis was confirmed. The second hypothesis suggested that viewing a domain description created using an object oriented grammar would lead to a higher level of "understanding" than viewing a description created using the "Structured Analysis" approach. The results confirmed the hypothesis that the group of participants using the Object-Oriented grammar scored higher in "understanding" than participants using the Structured Analysis grammar. A follow-up protocol analysis was undertaken to illuminate why the participants using object methods scored. The analysis of these protocols indicated two things. First, participants using Structured Analysis made little use of the Entity Relationship Diagram (ERD). Second, participants seemed to favor the "object" concept when answering questions. These findings provide some empirical evidence that objects may be more "natural" cognitive constructs than those used in Structured Analysis. The second study revisited a study Bodart and Weber's study regarding alternative grammars for the Entity Relationship Diagram. A grammar using mandatory attributes and relationships with sub types, the other using optional attributes and relationships, were compared. The grammars shared a common primary grammar, therefore, the second study was labeled an "Intragrammar" comparison. The new instrument was again used in this study. The ontological constructs proposed in the Bunge-Wand-Weber (BWW) model were used to suggest the theoretical advantage of the grammar using mandatory attributes and relationships with subtypes. The results supported the theoretical advantage associated with mandatory attributes and relationships with subtypes. This intragammar study provided further evidence of the utility of the empirical instrument proposed in this thesis. This study has implications for future empirical research in system analysis. The empirical instrument described in this thesis extends previous empirical research instruments with the introduction of the problem solving and the Cloze task. In two studies, the new instrument has displayed the sensitivity to differentiate between treatment groups. The results from the two empirical studies suggest that object-oriented analysis may hold advantages over traditional structured analysis, and that mandatory attributes and relationships may be preferred to optional attributes and relationships in the entity relationship grammar.
5

Method oriented design environments in knowledge aided design

Shurville, Simon John January 1999 (has links)
No description available.
6

'n Ontwerpsmetodologie vir verspreide databasisse

Rossouw, Anton 13 May 2014 (has links)
M.Com. (Computer Science) / Please refer to full text to view abstract
7

Empirical comparisons of system analysis modeling techniques

Gemino, Andrew C. 11 1900 (has links)
The development of information systems consumes an increasing share of economic resources. Over a trillion dollars worldwide is invested in information technology annually, and this investment is growing over $100 billion a year. This investment occurs despite failure rates for large information system development projects that are estimated as high as 75%. The large investment and high failure rates combine to create the potential for significant impact from information system development practices that are able to address these failure rates. Researchers, over the past thirty years, have studied factors that drive these high failure rates. One of the factors repeatedly mentioned in practitioner surveys is the importance of accurate communication in the "upstream" analysis and planning stage of a project. System development professionals are aided in their upstream planning through the use of information system development methods (ISDM's). ISDM's are modeling tools and techniques that are capable of representing information about an information system. Many alternative system analysis modeling techniques have been developed, yet few empirical comparisons of the alternative techniques have been completed. The lack of comparative empirical data has contributed to a proliferation of modeling methods and increased the confusion surrounding the adoption of system analysis methods by system development professionals and teachers. This study addresses the issue of empirical comparison of system analysis modeling techniques. A new instrument and empirical method is proposed for developing a comparison of the level of "understanding" that a participant is able to create by viewing a description of a particular domain. The level of "understanding" is addressed using three measures: comprehension, problem solving, and text reconstruction. The new measures of "problem solving", suggested by Mayer in the field of Education Psychology, and "text reconstruction" or "Cloze", suggested by Taylor in the field of Communications, extend empirical instruments previously used by system analysis researchers. To test the efficacy of the proposed instrument and method, two empirical studies were developed in this thesis. The first study used the new instrument to compare three development methods "grammars: Text descriptions; Structured Analysis (using Data Flow Diagrams and Entity Relationship Diagrams); and Object Oriented Diagrams. The study was labeled an "Intergrammar" comparison, as three grammars representing three fundamental approaches to developing an analysis model were compared. Two propositions, in regards to the intergrammar study, were tested. The first suggested that viewing descriptions created with diagrams would lead to a higher level of understanding than viewing a description based solely on text. This hypothesis was confirmed. The second hypothesis suggested that viewing a domain description created using an object oriented grammar would lead to a higher level of "understanding" than viewing a description created using the "Structured Analysis" approach. The results confirmed the hypothesis that the group of participants using the Object-Oriented grammar scored higher in "understanding" than participants using the Structured Analysis grammar. A follow-up protocol analysis was undertaken to illuminate why the participants using object methods scored. The analysis of these protocols indicated two things. First, participants using Structured Analysis made little use of the Entity Relationship Diagram (ERD). Second, participants seemed to favor the "object" concept when answering questions. These findings provide some empirical evidence that objects may be more "natural" cognitive constructs than those used in Structured Analysis. The second study revisited a study Bodart and Weber's study regarding alternative grammars for the Entity Relationship Diagram. A grammar using mandatory attributes and relationships with sub types, the other using optional attributes and relationships, were compared. The grammars shared a common primary grammar, therefore, the second study was labeled an "Intragrammar" comparison. The new instrument was again used in this study. The ontological constructs proposed in the Bunge-Wand-Weber (BWW) model were used to suggest the theoretical advantage of the grammar using mandatory attributes and relationships with subtypes. The results supported the theoretical advantage associated with mandatory attributes and relationships with subtypes. This intragammar study provided further evidence of the utility of the empirical instrument proposed in this thesis. This study has implications for future empirical research in system analysis. The empirical instrument described in this thesis extends previous empirical research instruments with the introduction of the problem solving and the Cloze task. In two studies, the new instrument has displayed the sensitivity to differentiate between treatment groups. The results from the two empirical studies suggest that object-oriented analysis may hold advantages over traditional structured analysis, and that mandatory attributes and relationships may be preferred to optional attributes and relationships in the entity relationship grammar. / Business, Sauder School of / Management Information Systems, Division of / Graduate
8

Design of Ultrawideband Digitizing Receivers for the VHF Low Band

Taylor, David Wyatt 24 July 2006 (has links)
The next generation of receivers for applications such as radio astronomy, spectrum surveillance, and frequency-adaptive cognitive radio will require the capability to digitize very large bandwidths in the VHF low band (30 to 100 MHz). However, methodology for designing such a receiver is not well established. The difficulties of this design are numerous. There are various man-made interferers occupying this spectrum which can block desired signals or spectrum, either directly or through intermodulation. The receivers will typically use simple (i.e., narrowband) antennas, so the efficiency of power transfer to the preamplifier needs to be carefully considered. This thesis takes these design challenges into account and produces a seven step design methodology for direct sampling wideband digitizing receivers. The methodology is then demonstrated by example for three representative receivers. Finally, improvements to the analysis are suggested. / Master of Science
9

Contribuição a metodologia de projeto e concepção automotiva. / Contribution to design methodology and automotive design.

Casa Nova, Sergio D\'Oliveira 25 October 2002 (has links)
O objetivo deste trabalho é fazer uma contribuição ao Método de Desenvolvimento Automotivo, especificamente sobre a concepção de novos produtos automotivos, por meio de uma análise crítica a partir de uma hipótese proposta de método de um estudo de caso. O estudo de temas pertinentes procurou incluir temas multidisciplinares ligados à Estética do Produto Industrial e à sua História, ao Gerenciamento de Projetos, a Metodologia de Estímulo à Criatividade, a Ergonomia e Fatores Humanos. O Método Proposto por hipótese, baseado na experiência do autor, incluiu de forma sintética quatro fases de desenvolvimento: a pesquisa, a proposição de alternativas, a definição da melhor alternativa e a execução. O estudo de caso está baseado em uma oportunidade de conceber um semi-reboque autoportante para produtos perigosos, o que permitiu que parte do método pudesse ser testada em sua eficiência. As conclusões do trabalho revelaram pontos em que a aplicação do método hipotético mostrou-se satisfatória e outros apresentou oportunidades de melhoria bem como de continuidade da pesquisa. / The contents on this work it is a contribution to Development automotive Method, specific to new products concepts, through a critical investigation. The theme study case was covered multi-disciplines topics such as: Product Esthetics and History, Project Management, Methods & Creativity stimulus and Human Factors. By the hypotheses the method proposal contemplated synthetic four phase development, Research, Alternative Solutions, Definition of he Solution and the Execution solution. The base study is supported by the opportunity to design a new product: No chassis truck trailer, to transport danger liquid materials, also to try this method for efficiency. The conclusions showed several points for hypothetical method applications with a satisfactory results, it is encouraging to continue this research.
10

Addressing complexity in product design : guidelines for product designers

Gollner, Mark, n/a January 2005 (has links)
Modern product design projects are often challenged by their interdisciplinary nature, increasing product complexity and time pressure. The challenge for product designers is to recall all relevant design aspects that are potentially applicable and important for the product to be designed at the right time. The negligence of certain design aspects may result in increased development costs and in inferior products. A recommended way to handle complexity in the design process is to work systematically, with checklists and guidelines offering a possibility to support product designers in this task. However, design guidelines that provide a comprehensive and generically content that support product designers holistically in their design projects are not readily available. Moreover, in-depth evaluations of the role, use, usefulness and usability of design guidelines are quite rare in the current literature. Therefore, the research study presented in this thesis sought to accomplish two tasks: the generation of a comprehensive set of generic and practically aimed product design guidelines in a paper-copy format that holistically supports product designers in their often complex design projects; and the evaluation of these generated design guidelines with the purpose of determining their role, use, usefulness and usability for product designers. A comprehensive and generically applicable set of product design guidelines in a ready-to-use paper-copy format that holistically provides in-depth information for the product design aspects that need to be considered during a design process was generated. Besides, a research study, using questionnaires and interviews, with product design students and professional product designers in New Zealand was carried out with the purpose of determining the role, use, usefulness and usability of the generated design guidelines for designers. As a consequence, valuable insights into the role of the guidelines as practitioners� design tool for professional designers and noteworthy findings about the role of the guidelines as educational tool for novice designers were obtained. The findings suggested that the use of guidelines as a tool in the design process is generally not very prevalent due to the designers� lack of knowledge about the benefits, location and accessibility of useful product design guidelines. Furthermore, it has been found that the designers used the generated guidelines sporadically and driven by their interest or demand in the design aspects applicable to their projects. In terms of the guidelines� usefulness it has been identified that the guidelines evaluated were generically applicable to different projects and provided a specific in-depth content. The guidelines have also been found to be quite useful as educational, planning, management and evaluation tool for novice and professional designers. However, in terms of the guidelines� usability, several problems were determined that made the generated guidelines too inefficient to be beneficial for the participants, especially for the professional designers. Accordingly, it has been concluded that a change of the guidelines� format into a digital interactive format, is likely to solve most of the identified problems and provide a useful and usable tool for product designers respectively.

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