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A Unified Approach to Quantitative Software Lifecycle ModelingRao, Vijay D 08 1900 (has links)
An evolutionary process currently taking place in engineering systems is the shift from hardware to software where the role of software engineering is becoming more central in developing large engineering systems. This shift represents a trend from a piece-meal vision of software development to a holistic, system-wide vision. The term "software crisis" of 1960's and 1970's was the observation that most software development projects end up with massive cost overruns and schedule delays. The growing complexity of software projects led to Waterfall, Spiral and other models to depict the software development lifecycle. These models are qualitative and study the product, process and project issues in isolation, and do not provide a quantitative framework to depict the various facets of development, testing, maintenance and reuse.
In this thesis, a generic, unified lifecycle model (ULM) integrating the product, process and project view of software development based on re-entrant lines is proposed. A reentrant line is a multi-class queueing network that consists of several types of artifacts visiting a set of development teams more than once. An artifact is a general term for any object of information created, produced, changed or used by development teams and it includes items such as requirements specification documents, preliminary and detailed module designs and design documents, code, components, test plans and test suites. The artifacts visit the development teams several times before exiting the system, thus making the flow of artifacts non-acyclic. The main consequence of the re-entrant flow is that several artifacts at different stages of completion compete with each other for service by a development team.
The ULM model output is obtained by using the criticality, complexity and usage of artifacts. The model is solved using linear programming and simulation methods. The software development process in a software organisation is represented by the proposed re-entrant line model. The model is used to predict project metrics such as the development time, cost and product quality for any new project to be taken up by the organization. The routing matrix of the artifacts in the ULM can be modified to derive different types of lifecycle models such as Waterfall, Prototyping, Spiral and Hybrid models.
The ULM may be modified to include software reuse and component-based development. We investigate certain issues involved in software reuse. Reuse of components is modeled as an external arrival of artifacts at different stages in the ULM. Two distinct lifecycles in component based software development, namely, 'development for reuse' and 'development with reuse', are distinguished and the development time and cost for projects are estimated using LP bounds and simulation.
The 'development for reuse' lifecycle involves reusable components development that is stored in a reuse library. As the number of components in the reuse library grows over time and with projects, the problem of effective and efficient retrieval of candidate components in order to facilitate systematic reuse becomes the bottleneck. A novel approach where components are stored in a case-base is proposed. The retrieval process is based on a reasoning approach that relies on similar cases (components) in the past to find solutions to the current problem (new software requirements in projects). The selection of candidate components for decisions pertaining to four levels of reuse {reuse as-is, reuse with minor code modifications, reuse of specifications, no reuse or develop afresh} in the current application is modeled using Rough and Fuzzy sets. These methodologies are illustrated with suitable case studies.
Maintenance of legacy systems, representing a massive, long-term business investment, is an important but relatively new research area. The ULM is modified to depict the complex set of activities associated with software maintenance. Quantitative metrics such as release time of versions, cost, time and effort for maintenance are estimated using this model. Some of the specific contributions of this thesis are:
1. A unified quantitative lifecycle model (ULM) depicting the software development process is used to obtain project metrics such as development cost, development time and quality based on the product and process attributes for the Waterfall, Prototyping, Spiral and Hybrid lifecycle models.
2. Analytic hierarchy process (AHP) methodology is used to rank order the suitability of different lifecycle models for a new development project at hand, based on the metrics obtained from ULM.
3. The ULM is modified to depict component-based software development and to integrate reuse as an important basis for software development. Two distinct lifecycles for development for reuse and development with reuse are studied. The 'development for reuse' strategy generates reusable components that are organized and stored in a reuse library. The selection-decision regarding candidate components from this library for reuse in the current application is derived using a Rough and Fussy set methodology.
4. The ULM is adapted to represent the various activities associated with software maintenance. Estimates of maintenance metrics for different strategies of maintenance of legacy systems are obtained.
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Modelling the Demand Evolution of New Shared Mobility Services / 新しい共有モビリティサービスの需要進化のモデリングZhang, Cen 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21747号 / 工博第4564号 / 新制||工||1711(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 山田 忠史, 准教授 SCHMOECKER Jan-Dirk, 教授 宇野 伸宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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Řízení projektů kompetenčního centra SQA / Project Management of the SQA Competence CentreŠiroký, Jiří January 2015 (has links)
This thesis describes the design and application of the methodology for project management of the Software Quality Assurance Competence Centre. In short theoretical introduction the thesis mentions the basic concepts associated with project management, including several examples of methodologies for project management. Then the thesis introduces the concept of Competence Centers at the University of Economics, Prague and identifies the specifics of the SQA Competence Centre's projects, or the specifics of managing these projects. Theses specific serve as a basis for design of the methodology for project management of the SQA Competence Centre, which consists of seven dimensions that cover various areas of project management. A crucial part of this methodology can be considered a project lifecycle model and process model of project management of the SQA Competence Centre. The methodology is then applied to the project management of the Integrated Testing Tools. Application of the designed methodology made this project and its management more transparent and efficient. This usage of the methodology also highlighted the importance of project manager's ability to motivate project team members. The main outcome of the thesis is designed and proven methodology for project management of the SQA Competence Centre with possible application in projects other Competence Centers operating at universities.
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An evaluation framework for virtual reality safety training systems in the South African Mining IndustryVan Wyk, Etienne Anton 02 1900 (has links)
The mining industry in South Africa contributes significantly to the national economy. Despite stringent safety legislation, mining accidents cause numerous fatalities and injuries. Inadequate or insufficient training is often cited as a root cause of accidents. Conventional class-based safety training has not reduced the incidence of accidents significantly. By contrast, virtual reality training tools can provide simulated exposure to real-world working conditions without the associated risks.
This study describes the application of design-based research (DBR) in the design and development of two desktop virtual reality (VR) systems for safety training in the South African mining industry. The results of a usability context analysis were applied in the design of a VR prototype on generic hazards recognition and rectification, which was used and evaluated at South Africa‘s largest platinum mine site. A case study was conducted to investigate the causes and occurrences of falls of ground, which resulted in the design and development of a second VR prototype focusing on identifying and addressing underground geological conditions.
DBR was also used in the generation of an evaluation framework for evaluating VR training systems, namely the Desktop VR Evaluation Framework (DEVREF), which is the major deliverable of the research. DEVREF can make a major contribution to the domain of e-training in mines and is transferable and customisable beyond its initial application. The process flow of the research thus moved beyond merely providing a solution to a complex real-world problem and became a classic DBR study with dual outcomes, namely a practical real-world solution in the form of two VR training systems and a theoretical contribution in the form of the DEVREF evaluation framework. DEVREF evaluates the design of desktop VR training systems in the categories of instructional design, usability, VR systems design, and context-specific criteria for mining. The use of DEVREF is demonstrated by reporting the application of its criteria in evaluating the two VR training systems. Heuristic evaluation, end-user surveys, and interviews were used as evaluation methods.
A third contribution is methodological, in that this work proposes a new DBR process model and an interaction design lifecycle model suitable for VR training systems. / Computing / D. Phil. (Information Systems)
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