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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.
1051

Heuristic Rule-Based Phase Balancing of Distribution Systems by Considering Customer Load Patterns

Ho, Cheng-Yu 10 June 2004 (has links)
In this paper, a heuristic backtracking search algorithm is proposed to adjust the phasing arrangement of primary feeders and laterals for phase balancing of distribution systems. The phase unbalance index of distribution feeders is calculated based on the phasing current magnitude of each line segment and branch, which has been solved by a 3-phase load flow program. The database of an automated mapping/facility management (AM/FM) system is used to retrieve the component attributes and topology process is executed to determine the electrical network configuration and to identify the customers served by each distribution transformer. By using the monthly energy consumption of the customers in customer information system (CIS) and the typical daily load patterns of customer classes, the hourly loading profiles of distribution transformers can be derived, which can be integrated to solve the load demand of each service zone. By this manner, the individual phase loadings of each primary feeder and lateral can be determined based on the phasing of distribution transformers and the power consumption served. The optimal phase balancing of distribution systems is performed by heuristic rule-based searching process to minimize the phase unbalance index so that the proper phasings of a primary feeder and its lateral can be assigned. To demonstrate the effectiveness of proposed methodology to enhance three-phase balancing of distribution systems, a practical distribution feeder with 2754 customers are selected for computer simulation. It is concluded that three phase balancing of distribution systems can be obtained by properly phasing design of primary feeders and laterals by considering customer load characteristics.
1052

Application of Integrated Watershed Management Modeling on Non-point Source Pollution Evaluation for the Ai-Liao River Basin

Shen, Wei-Lin 23 August 2006 (has links)
In Taiwan, non-point source (NPS) pollution is one of the major causes of the impairment of surface waters. NPS pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. The I-Liao Creek Basin, located in southern Taiwan, flows through approximately 90-km and drains towards the Kaoping River. It is one of the major sub-basin in the Kaoping River watershed, which is the largest and the most intensively used watershed in Taiwan. Field investigation results indicate that the main water pollution sources in the I-Liao Creek Basin are domestic wastewater and NPS pollutants from agricultural activities. In this study, an Integrated Watershed Management Model (IWMM) was applied for simulating the water quality in the I-Liao Creek watershed. The model includes a global atmosphere module, a land module, a human impact module, a canopy module, and a global ocean module. Those modules can be linked and managed by a graphic user-interface. The model was calibrated and verified with field data, and was used to investigate potential NPS pollution management plans. Moreover, the Storm Water Management Model (SWMM) was used to verify the accuracy of the simulated results of flow and water qualities. Results from this study show that geographical information system (GIS) is an important mean for land-use identification and waste load estimation in the catchment. Linking the information of land utilization with the NPS pollution simulation model may further provide essential information of pollution potential of NPS pollution for all sub-regions in the river basin. Results and experience obtained from this study will be helpful in designing the watershed management and NPS pollution control strategies for other similar river basins.
1053

A Study on User Satisfaction and Acceptance of MOD

Kao, Yu-ting 25 August 2006 (has links)
In an era of digital convergence, people in related fields are devoted to activities of digitalization, especially in digital TV. This research is based on the Information System Success Model from Technology Acceptance Model (TAM) and aimed to understand the factors that affect user satisfaction and acceptance behavior. The researcher adopts the methodology of questionnaire survey. After statistical data analyses, the results show the main factor that influences MOD users¡¦ intention to use is perceived usefulness. Furthermore, perceived usefulness is influenced by perceived ease of use and user satisfaction. Three factors related to perceived ease of use and user satisfaction are program content quality, system quality and service quality of MOD. However, the influence of information quality is not significant. This research successfully constructs a technology acceptance model for MOD development and contributes for reference not only to future researches on users concerning innovative technologies but also to specific guidance for MOD operators to improve their services, expediting the development of digital TV in Taiwan.
1054

Designing An Information System For Material Management In Engineer-to-order Organizations

Dede, Erdogan 01 January 2007 (has links) (PDF)
In this thesis, an information system is designed and developed for engineer-to-order organizations to improve the traditional Bill-of-Material by handling variants of products and components efficiently. A database is developed to store the related information about inventories and configuration management in an effective way. The improved Bill-of-Material provides a common structure to access stored information for material management purposes. A model, based on network, is presented and included into the system for calculating time required to produce components and to make subassemblies or assemblies with the current inventory levels. The system is applied to T&Uuml / BiTAK-SAGE, which is an engineer-to-order organization carrying out Research and Development projects for Defense Industry.
1055

A Conformance And Interoperability Test Suite For Turkey

Sinaci, Ali Anil 01 June 2009 (has links) (PDF)
Conformance to standards and interoperability is a major challenge of today`s applications in all domains. Several standards have been developed and some are still under development to address the various layers in the interoperability stack. Conformance and interoperability testing involves checking whether the applications conform to the standards so that they can interoperate with other conformant systems. Only through testing, correct information exchange among applications can be guaranteed. National Health Information System (NHIS) of Turkey aims to provide a nation-wide infrastructure for sharing Electronic Health Records (EHRs). In order to guarantee the interoperability, the Ministry of Health (MoH), Turkey, developed an Implementation/Integration/Interoperability Profile based on HL7 standards. TestBATN - Testing Business Process, Application, Transport and Network Layers - is a domain and standards independent set of tools which can be used to test all of the layers of the interoperability stack, namely, the Communication Layer, Document Content Layer and the Business Process Layer. In this thesis work, the requirements for conformance and interoperability testing of the NHIS are analyzed, a testing approach is designated, test cases for several NHIS services are developed and deployed and a test execution control and monitoring environment within TestBATN is designed and implemented through the identified testing requirements. The work presented in this thesis is part of the TestBATN system supported by the T&Uuml / BiTAK TEYDEB Project No: 7070191 in addition by the Ministry of Health, Turkey.
1056

Gis-based Site Selection Approach For Wind And Solar Energy Systems: A Case Study From Western Turkey

Aydin, Nazli Yonca 01 July 2009 (has links) (PDF)
Many countries around the world integrated Renewable Energy Systems (RES) in their future energy plans in order to reduce negative impacts of fossil fuel consumption on the environment. However, RES may as well cause various environmental problems which are mostly related with the geographic locations of these facilities. The aim of this thesis is to create a Geographic Information System-based methodology for evaluating alternative locations for wind, solar and hybrid power plants by using fuzzy multi-criteria decision making. Environmental objectives and economical feasibility criteria for wind and solar systems are identified through Turkish legislations, previous studies, and interviews with General Directorate of Electrical Power Resources Survey and Development. Individual satisfaction degrees for each alternative location with respect to the identified environmental objectives and economical feasibility criteria are calculated using fuzzy set theory tools. Then these individual satisfaction degrees are aggregated into overall performance indexes which are used to determine priority maps for wind and solar energy generation facilities. Finally, maps of priority sites for wind and solar energy systems are overlaid to identify suitable locations for hybrid wind-solar energy systems. The proposed methodology is applied on a case study area composed of USak, Aydin, Denizli, Mugla, and Burdur provinces.
1057

Modeling And Assessment Of Theeffectiveness Of Government Information Systems

Guclu, Aydin Nusret 01 June 2011 (has links) (PDF)
In the context of evaluating effectiveness of information systems, the public sector requires a specific approach for measuring indirect benefits such as strategic / political value. There is not yet a holistic approach and no unified adaptive and time-variant model addressing the problem. In this thesis, Strategic Management Model developed and partially applied at the Ministry of Finance, Turkey, is described. The model is based on the public value delivery chain, from strategic goals to accountability reporting. Public Financial Management Value Space is built step by step, and a method is defined on the Value Space for effectiveness assessment through calculation of five value components, namely the Agency Value, User Value, Political Value, Strategic/Social Value, and Environmental Value, using weighted summation of key goal and performance indicators. Value space is mapped to ontology, then to the object model for flexible system implementation. The assessment calculation method, resulting in a single value allows for a-posteriori benefits assessment, allows not only for cross-comparison of programs, agencies, functions, etc. by fixing the values on the dimensions of the value space under analysis, but also standardization and consolidation. Economy, efficiency and effectiveness are linked as an extension of the assessment model by introducing the expenditure component of the budget. The model has been applied to two case studies of Information System investments at the Ministry of Finance, and a cross-comparison of these initiatives has been provided.
1058

Expectation Based Evaluation Framework For Hostpital Information Systems

Gursel, Guney 01 February 2011 (has links) (PDF)
Evaluation is essential for Medical Informatics as well as many other disciplines. There is a growing interest and investment for evaluation researches and self evaluation works. Hospital Information System (HIS) evaluation frameworks have largely been discussed in the literature. However, existing frameworks lack one important aspect, to what extent user expectations from HIS are met. To complement this deficiency we designed an evaluation farmework for evaluating the user expectation in HIS. User expectation data are collected by means of &ldquo / Expectation Questionnaire&rdquo / . Fuzzy logic methodologies are used to evaluate the expectation meeting in the proposed evaluation framework. The evaluation variables are not represented in the result equally / they are reflected by the weights assigned by the users. Our proposed framework provides the overall degree to what extent user expectations are met. It also gives the opportunity to analyze to what extent each expectation is met and degree to what extent different user groups&rsquo / expectations are met. Education, sex and business title is determinants of general expectations about HIS. IS experience is not a determinant of medical users&rsquo / expectations in any expectations. The proposed framework is not a rival but an alternative or complementary to the existing frameworks. It is a different approach and has different computation methodology supported by fuzzy logic. The framework can give detail to the each variable level. These results are just a photo of the current situation / a deeper analysis of these findings must be done for further information about the causes of these results.
1059

Development Of A Web Gis-based Tsunami Inundation Mapping Service / A Case Study For Marmara Sea Region

Ayca, Aykut 01 June 2012 (has links) (PDF)
Tsunamis, as the catastrophic disasters, can cause loss of live and property when they come to the shores. Preparation of emergency plans is essential to reduce the damage. Consequently, any initiative in tsunami modeling and inundation mapping is of vital importance for progressing safety surveillance and maintenance. In an effort to achieve a thorough analysis of effect of tsunami, it is critical to estimate the geographical extent of possibly affected area and to predict tsunami impacts. The inundation mapping system also must serve to manage the simulation data in a scalable environment to reach end-users in the time of event. For this purpose, in this study, the generation of a Web based Geographic Information System (GIS) to serve inundation maps through web. The research methodology consists of four main stages: (i) simulating tsunamis based on six different scenarios (ii) processing simulation data through a GIS application / (iii) development of web interfaces and implementation of the developed model for Web-GIS application / (iv) verification of the created model for Marmara Sea Region. The proposed system is expected to be an efficient tool for improving inundation mapping efforts for expected tsunamis in Turkey.
1060

Reengineering and Development for Executive Information Systems : The Case of Southern Taiwan Business Group of Chunghwa Telecom

Chang, I-Ming 03 August 2000 (has links)
In the earlier period, large enterprise, developed its management reports system based on files system and the 3rd-generation language. The managers of several departments access management information from the reports system. Because competition stress increasing quickly and information requirement changing frequently, the legacy system could not satisfy the information need of managers. The maintainability of legacy system is decreasing, and the cost is growing up. How to solve the difficulties on system maintenance ? System reengineering is commonly used as a solution. How to choose a good migration strategy is also a big issue. This research focuses on finding a migration strategy for the legacy systems and a methodology of developing EIS based on users¡¦ needs via current new information technologies. The methodology is applied to implement a EIS for a large enterprise in order to verify the feasibility of the methodology. A questionnaire investigation among the users of the new system has clearly shown a fairly good users¡¦ satisfaction.

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