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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

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.
2

Tree manipulation algorithms and the design processing software

Wilson, A. D. January 1986 (has links)
No description available.
3

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.
4

Method oriented design environments in knowledge aided design

Shurville, Simon John January 1999 (has links)
No description available.
5

'n Ontwerpsmetodologie vir verspreide databasisse

Rossouw, Anton 13 May 2014 (has links)
M.Com. (Computer Science) / Please refer to full text to view abstract
6

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
7

Tools for innovation and conceptual design

Karuppoor, Srinand Sreedharan 15 November 2004 (has links)
The ability to design is the distinguishing characteristic of an engineer. Recent research has increased our understanding of both the engineering design process and effective means for teaching that process to neophyte design engineers. In that spirit, a design methodology was developed at the Institute for Innovation and Design in Engineering (IIDE), Texas A&M University. At the core of this approach is a design philosophy based on the cognitive skills of Abstraction, Critical Parameter Identification, and Questioning. This philosophy along with the design process is taught in the senior undergraduate design and graduate design courses. The goal of the methodology is not only to teach the design process to novice designers but also to instill in them the design philosophy that would enable them to perform design effectively and innovatively in any area of specialty. In this dissertation the design philosophy along with its role in the design methodology is explained. The Need Analysis and the Conceptual Design stages of the IIDE methodology are elaborated. The weaknesses in these stages are identified and addressed, by developing and incorporating design methods and techniques that fit the spirit and framework of the IIDE design methodology. The Object Function Method was developed to address certain aspects at the Need Analysis stage. There was need for an effective concept searching method within the Concept Design stage of the IIDE design methodology. This is addressed by the development of new search techniques and methods for effective concept discovery during concept searching. The usage and application of these methods and techniques is explained in detail along with examples. Additionally, this dissertation contains the results of a study conducted with two groups of senior design students, those who have been through the process and those who have not, to evaluate the effectiveness of applying the IIDE design philosophy and performing the Need Analysis and Conceptual Design stages for the given design challenge. The goal of the study was to investigate the relationship, if any, between the degree to which these aspects of the design methodology were followed and the quality of the resulting design solutions produced.
8

Private family garden + phenomenology + deconstructivism : alias landscape design cooking a la Czech

Kovář, Martin 11 1900 (has links)
Private family garden + phenomenology + deconstructivism; alias landscape design cooking a la Czech is a thesis project the main purpose of which was to answer authors questions concerning the practical use of the two design approaches applied to project for a real site through a development of designs driven by the principles of the respective styles/movements. Emphasis were paid to the influence the movements have on architectural and garden design. Second aim was to investigate the appropriateness and usefulness of designing through a model creation in a miniaturised simulation of the real situation in three dimensions. Following, and the last step, was to investigate the effectiveness of the model to communicate and truthfully represent/simulate the impact of the proposed design interventions. Throughout the work on the project, stages and consecutive steps taken were recorded to document the process. Development of the project was divided into several phases. First, suitable site was chosen and data related to the property gathered. Second, phenomenology and deconstructivism had been studied - mainly through looking at precedent design work and development of visual annotated analysis. Third step, happening simultaneously with second, was creation of a model simulating the current state and conditions on the site. Fourth, preliminary design proposals were developed. As a reflection on step four, design guidelines were developed (step five) to provide more steady ground/base for development of a coherent and better focused final design, which was the product of step six. In the seventh step, a rough model of the final design was developed and had been gradually refined into a stage of a final model with minor changes to the design elements occurring throughout the process. The changes were executed as they became desirable after the three dimensional simulation of the proposed design was developed and a higher level of understanding of the spatial relations was achieved. In conclusion, a high effectiveness of the model "to tell the story" was observed and emphasized even further by digital photo-documentation targeted to "draw the viewer into the model space." Lessons about time demands for the model creation were learned and better level of understanding the way deconstructivism and phenomenology reflect in design work was achieved.
9

Function based techniques for assisting engineering conceptual design

Vinney, John Edward January 1998 (has links)
The basic concept of this work is that functional modelling techniques are applicable to and of practical use in, producing a qualitative model of conceptual engineering design. A qualitative function based model of conceptual design has been developed and a computer based implementation has been built and tested. The rationale behind the modelling scheme and the computer implementation are described in detail. In addition to a review of existing models of design the research provides a significant new capability in four main areas: • An ability to generate new concepts with a controlled degree of similarity to existing designs. • A new function based model of engineering conceptual design. • The COncept Design ASsistant (CODAS) system, a computer based implementation of the function based model, has been developed and tested. • A new symbolic representation language. CODAS is a hybrid case-based and function-based modelling system, implemented in the domain of mechanical device design, which demonstrates the practical application of this new model. The CODAS system aims to provide a design support tool which can invent both routine and novel devices based on experience gained from past successful design solutions. Fast and efficient data handling is achieved by utilizing Case Based Reasoning (CBR) technology to store and retrieve past design solutions which are defined in terms of a symbolic representation language. The underlying design model is function based and employs a technique of divergent function to form mapping to produce physical embodiments of the proposed functional solutions.
10

Lifestreaming as a life design methodology

Mullen, Jessica E. 29 November 2010 (has links)
My research explores the potential of lifestreaming as a life design methodology. Life design is the design of one’s daily activities, habits and relationships. Like graphic or industrial design, life design can be approached using a specific methodology to solve problems–in the case of life design, problems of individual, daily life. “Lifestream” was first defined by computer scientist David Gelernter as a software architecture consisting of a time-ordered stream of documents. Lifestreaming has evolved into the act of documenting and sharing aspects of daily existence online. A lifestream website collects the things you choose to publish (e. g., photos, tweets, videos, or blog posts) and displays them in reverse-chronological order. Putting one’s life online might provide the critical perspective to help redesign it. After practicing lifestreaming for two years and performing four lifestream website experiments, I have devised a lifestreaming system that encourages users to gain more control over personal advancement and deliberate decision-making. / text

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