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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.
441

On developing an expert system: a knowledge base for GP formulation and analysis

Aggarwal, Ajay K. 13 July 2007 (has links)
An expert system approach to help OR naive users formulate and solve goal programs is proposed. The approach is demonstrated for single product blending problems using VP-Expert as the developmental tool. Results of a study using undergraduate and graduate business students to test the expert system effectiveness are provided. An expert system determines the problem type using a taxonomy based upon problem context. Each problem type possesses distinct characteristics. Characteristics of twenty-four different problem types are discussed. Formulation of constraints using problem characteristics is demonstrated. The expert system uses constraint information to assist users in goal selection. Goal structures are constructed using a pairwise comparison technique. Solution values, recommendations based upon sensitivity analysis, and trade-offs between conflicting goals are provided to the user. A feedback loop permitting model changes and reiteration of solution and recommendation steps is provided. / Ph. D.
442

Incorporating concurrent engineering and design economics in a decision support system

Lee, Pui Mun 14 December 2006 (has links)
Concurrent engineering is a philosophy for improving design communication and aiding the process of recognizing and resolving design conflicts. Design economics is an integrated part of the concurrent engineering process, since cost-effective product design is at the root of many design conflicts. However, the bulk of research on concurrent engineering focuses on deriving better methods for coordinating both product and process designs with respect to functionality and manufacturability issues. The issue of implementing design economics via the concurrent engineering process at the conceptual design stage has not been adequately addressed. This research explores the development of a structural framework for incorporating concurrent engineering and design economics into a prototype decision support system that supports the conceptual phase of the product design process. The dissertation has three major tasks: (1) To formulate a concurrent engineering framework for use during the conceptual design stage, (2) To develop an activity-based cost estimation model for estimating product cost at the conceptual level of product design, and (3) To integrate and demonstrate the concurrent engineering framework and the activity-based cost estimation model together in a prototype decision support system. To accomplish the objective of this research, electronics manufacturing is used as an application setting. The design of printed circuit board assemblies is the domain for establishing a structural framework for incorporating concurrent engineering and activity-based cost estimation. / Ph. D.
443

Application of GIS in propagation prediction

Rajguru, Chaitanya Shreeniwas 04 May 2010 (has links)
This thesis presents an application of a geographical information system (GIS) in propagation prediction. The motivating force behind this work is the need for accurate and efficient site-specific propagation prediction tools for personal communication system (PCS) design. Site-specific information including terrain and building attributes is vast and complex, and needs specialized handling. A geographical information system provides these capabilities, and relieves the propagation analysis tools of the burden of data management. This work focused on harnessing the relevant abilities of a GIS for aiding the current propagation prediction software. GRASS (Geographical Resources Analysis Support System) GIS has been used for data handling, transformation, and analysis. Schemes and techniques were developed for operations on site-specific data as used in propagation prediction. Attention was paid to the types of data needed, available data sources and their formats, and the needs of the propagation analysis software. These schemes were implemented in the form of several new programs that have been integrated with GRASS. Data interfacing is the major function performed by these programs. Building and terrain data may now be exchanged between GRASS and AutoCAD, a computer-aided design software package. The data analysis powers of the GIS were used for estimating diffraction path loss over terrain. The results of propagation prediction can be displayed in a graphical manner through the GIS, and hardcopy outputs are possible. The work presented here sets the framework for the integration of various software modules that can combine to form a propagation prediction tool. / Master of Science
444

Design and Development of an Electronic Performance Enhancement Tool for Creating and Maintaining Information Management Web Sites

Bowden, Todd H. 18 April 2011 (has links)
This study explored the design and development of an electronic performance enhancement tool that can assist a person with limited programming skills to create a variety of simple customized information management websites. In particular, this study was modeled after needs within an Instruction Technology department in which individuals were able to create pre-functional web pages with various elements such as textboxes and dropdown menus but lacked the programming skills necessary to add functionality to these web forms. Skilled programmers could add functionality to these pre-functioning web forms or create customized information management websites from scratch. However, programmers are not always available when needed. At the time of this study, there was no readily available way for persons to create customized information management websites without the services of a programmer or without needing to learn programming skills themselves. This study sought to determine what functionalities, characteristics and capabilities could be included in an electronic performance enhancement tool to assist non-programmers to create simple customized information management websites and how a tool with such functionalities, characteristics and capabilities could be designed and developed. A prototype version of such tool (named the Form And DataBase Interaction Tool or "FADBIT") was designed and developed in this study. This tool asks users who have created simple pre-functional web forms to answer a series of questions related to those webforms. Given the user's responses to these questions, this tool is able to form a metalanguage representation of the user's intentions for the web form and can translate this representation into useful programming code to add the desired functionality. The tool was successfully designed and developed using a generalized modular framework, and a Create-Adapt-Generalize model, with each module addressing one or more patterns common to web programming. The prototype tool successfully allowed non-programmers to create functional information websites for two structured evaluation projects, and achieved some level of success and encountered some difficulties with an unstructured project. Proposed modifications and extensions to the tool to address the difficulties encountered are presented. / Ph. D.
445

Discrete Event Simulation Model for Project Selection Level Pavement Maintenance Policy Analysis

Uslu, Berk 25 March 2011 (has links)
A pavement investment and management process has a dynamic structure with cause and effect. Better investment decisions for maintenance will increase the condition of the flexible pavement and will end up with a better level of service. Therefore, better investments decisions on pavement maintenance will increase the economic growth and global competition for the area. However, improper allocation of money and resources would end up with further deteriorations of the facilities. So asset management encourages highway maintenance managers to spend their scarce budget for the maintenance that is really needed. A well-developed pavement management simulation model will allow highway maintenance managers to consider the impact of choosing one maintenance policy alternative versus another through what-if analysis and having informed decisions. Discrete event simulation (DES) is an alternative method of analysis that offers numerous benefits in pavement management. Unlike the models currently in use, a decision support model created by utilizing the DES technique would allow fractionalizing the pavement in smaller proportions and simulating the policies on these smaller segments. Thus, users would see how their decisions would affect these specific segments in the highway network over a period of time. Furthermore, DES technique would better model the multiple resource requirements and dynamic complexity of pavement maintenance processes. The purpose for this research is to create a decision support tool utilizing discrete event simulation technique where the highway maintenance managers can foresee the outcomes of their what-if scenarios on the specific segments and whole of the highway network evaluated. Thus, can be used for both project and network level decision support. The simulation can also be used as a guiding tool on when, where and why resources are needed on needs basis. This research relies on the budget allocation results from the linear optimization model (LOM). This model is a tool that creates the optimized budget allocation scheme for a network fitting to a determined scenario. Thus by integrating the LOM and the DES model, the maintenance managers can acquire an optimized budget allocation for their district and evaluate the results in both network and project selection level. Maintenance managers can obtain the best budget allocation plan without performing the repetitive trial and error approach like the previous decision support tools. There is a vast amount data in many varieties gathered as results from the simulation model. This fact alone demonstrates how powerful the discrete event simulation model is. By the nature of this simulation technique, the resources (highway segments, annual budget) can be traced throughout the simulation and this trait allows the design of the project selection level decision support system. By examining these reports, the maintenance managers can better observe how the scenarios evolve. Thus this tool helps the maintenance managers to have better decisions on the project selection level. The discrete event simulation model established in this research carries the project selection level pavement management from a position where maintenance managers should solely depend on their engineering judgment and experience to a position where maintenance managers can have more effective and justified plans since they can foresee the results of these decisions on the segments that are forming the network. This simulation engine is created with the discrete event simulation language called STROBOSCOPE. The model consists of two parts which work like a lock and key mechanism. The first part of the model is the data feeding mechanism where information from any network is loaded. The second part is the generic engine which can evaluate any road network data it is fed. The purpose of segregating these two components of the model is to allow the user to evaluate any network regardless of length, number of segments or the location. / Master of Science
446

A methodology to evaluate uncertainties in planning small-scale power systems

Teklu, Yonael 04 August 2009 (has links)
Planning and engineering activities in small-scale power systems are, in most of cases, driven by immediately pressing factors such as short-term demand, system costs, expected revenues, and local development priorities. Often, the decision to go ahead with the investment in such systems is based on the outcomes of single-attribute spreadsheet type analyses and linear optimization runs where key parameters such as demand growth, interest rates, capital costs, and fuel prices are assumed to remain constant throughout the study period. The least-cost plan thus obtained is subject to changes in the above parameters requiring continual re-evaluation and assessment to bring the project up to date. An alternative method is hereby presented in which the uncertain parameters in a seemingly deterministic model were identified ahead of time. The range of values that each of these parameters could assume as well as the respective probabilities were elicited from the experts and incorporated in a decision analysis problem designed to generate the least-cost policy. The decision analysis process resulted in a robust evaluation of generation options under investigation when compared to the results of the deterministic analysis. Moreover, options ranked least in the deterministic analysis became quite competitive when uncertainties were included in the analysis. / Master of Science
447

A decision support tool for preliminary system design

Tarnoff, David Lee 31 October 2009 (has links)
The development methodology for today’s computer systems is lacking in the area of preliminary design. Decisions that greatly influence the product’s life-cycle cost are made during this stage of the design with minimal knowledge. One of the key decisions made during preliminary design is the allocation of the system’s functions to hardware, software, or firmware implementations. This research investigates methods to automate the decision making process during preliminary design. These decisions include the hardware, software, and firmware allocation process and the reduction of the preliminary design space by ordering the design space and determining a cut-off point. A general system model is presented based on the top-down design methodology. A decision process is applied to the lowest level functions of the system model to order the allocation design space. The methods explored to perform decisions are the general linear model and fuzzy logic membership functions. A computer based tool is developed that applies the decision methods to a system model. The output of the tool is a set of optimum hardware/software/firmware function allocations. The application of this tool greatly reduces the overall allocation design space which allows the human designer to make improved decisions during preliminary design. / Master of Science
448

Clinician Decision Support Dashboard: Extracting value from Electronic Medical Records

Sethi, Iccha 07 May 2012 (has links)
Medical records are rapidly being digitized to electronic medical records. Although Electronic Medical Records (EMRs) improve administration, billing, and logistics, an open research problem remains as to how doctors can leverage EMRs to enhance patient care. This thesis describes a system that analyzes a patient's evolving EMR in context with available biomedical knowledge and the accumulated experience recorded in various text sources including the EMRs of other patients. The aim of the Clinician Decision Support (CDS) Dashboard is to provide interactive, automated, actionable EMR text-mining tools that help improve both the patient and clinical care staff experience. The CDS Dashboard, in a secure network, helps physicians find de-identified electronic medical records similar to their patient's medical record thereby aiding them in diagnosis, treatment, prognosis and outcomes. It is of particular value in cases involving complex disorders, and also allows physicians to explore relevant medical literature, recent research findings, clinical trials and medical cases. A pilot study done with medical students at the Virginia Tech Carilion School of Medicine and Research Institute (VTC) showed that 89% of them found the CDS Dashboard to be useful in aiding patient care for doctors and 81% of them found it useful for aiding medical students pedagogically. Additionally, over 81% of the medical students found the tool user friendly. The CDS Dashboard is constructed using a multidisciplinary approach including: computer science, medicine, biomedical research, and human-machine interfacing. Our multidisciplinary approach combined with the high usability scores obtained from VTC indicated the CDS Dashboard has a high potential value to clinicians and medical students. / Master of Science
449

Strategic Conservation Planning for High Knob, Virginia: A GIS Decision Support Approach

Elmore, James Link 15 June 2012 (has links)
Conservation strategies frequently require prioritization of targets due to limited budgets and personnel. Prioritization involves choosing those areas that return the most conservation value for the time and money invested. Hence, the process of prioritization involves evaluating multiple conservation values and the uneven spatial distribution of those values across a landscape of concern. The goal of this study was to help conservation organizations improve decision making for implementation of prioritization-based strategies for land protection using a GIS-based, multi-criteria decision support system (GIS-MCDS). Geographic Information Systems (GIS) can assist conservation planners in quantifying the relative desirability of one area over another, therefore enabling better business and ecological decisions. GIS analyses for planning are routinely undertaken over large geographic extents such as ecoregions to identify priority areas. These analyses often summarize priority by pixel values in a raster image. Implementation of conservation strategy often takes place at the much larger parcel level. Therefore, aggregating pixel-based results by parcels is a prerequisite to implementation of a purchase or easement strategy. I developed a spatial decision support system in an attempt to quantify private land holdings in the High Knob area of Virginia for their relative conservation value, as defined by the Clinch Valley Program of The Nature Conservancy. It utilizes a proxy approach for measuring conservation values and an analytical hierarchy process to aggregate the results by privately held real estate parcels. Simple prioritizations are often based on parcel size alone, rather than consideration of the many conservation values that characterize land parcels. Though it is much quicker and easier to prioritize parcels in this manner, such simplicity risks missing important smaller areas for conservation while prioritizing larger parcels with less value. I compared this simple "bigger is better" ranking method to the GIS-based multi-criteria method developed for TNC. There was a 0.57 correlation between the ranked lists produced by the two models, suggesting that parcel size alone does partially explain the complexity modeled by the multi-criteria method. However, the more complex method did produce different top priority parcels, which could significantly change an organization's implementation strategy. I conclude that both methods have their applications, though the multi-criteria method is better for long-term implementations of strategic acquisition and easement. A secondary goal was to identify to what extent land trust organizations are prepared to implement a multi-criteria type analysis like the one considered in this study. I conducted an online survey of conservation professionals on how their organization currently uses GIS and their satisfaction with GIS analyses to meet their organizational mission. Sixty-one responses were collected and analyzed. The overwhelming majority of conservation organizations recognize the benefits that GIS bring and have already developed some level of internal expertise, though many barriers to using GIS were also identified. From these results, I conclude that most land trust conservation organizations are not currently utilizing the insights that multi-criteria GIS prioritization is capable of offering, but that their previous positive experience with GIS makes such analyses an attractive proposition for those on the cutting edge of the land conservation movement. / Master of Science
450

Fostering Smart Cities through ICT Driven Policy-Making: Expected Outcomes and Impacts of DAREED Project

Sivarajah, Uthayasankar, Lee, Habin, Irani, Zahir, Weerakkody, Vishanth J.P. 07 1900 (has links)
Yes / The concept of smart city is emerging as a key strategy to tackle the problems generated by the urban population growth and rapid development. It is widely recognised that Information and Communications Technology (ICT) play a key role in addressing some of the urban societal challenges such as improving energy efficiency and reducing carbon emissions. Although there are various ICT tools providing intelligence and services relating to energy consumption and monitoring processes, they mostly tend to work in isolation. Therefore, this paper presents the outcomes and impacts of the concept of DAREED which aims to deliver an integrated ICT service platform to drive energy efficiency and low carbon activities at neighbourhood, city and district levels. Furthermore, the research highlights the need for ICT-driven policy making using platforms such as DAREED in the context of e-Government. This paper contributes to the current understandings of e-Government literature in terms of how ICT can help public authorities and stakeholders such as policy makers to achieve and drive energy efficiency. From a practical stance, the paper offers valuable insights to public administrations on how ICT can be used to address pressing societal challenges such as efficient energy use and facilitate better policy making.

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