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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.
291

Acquisition of Fuzzy Measures in Multicriteria Decision Making Using Similarity-based Reasoning

Wagholikar, Amol S, N/A January 2007 (has links)
Continuous development has been occurring in the area of decision support systems. Modern systems focus on applying decision models that can provide intelligent support to the decision maker. These systems focus on modelling the human reasoning process in situations requiring decision. This task may be achieved by using an appropriate decision model. Multicriteria decision making (MCDM) is a common decision making approach. This research investigates and seeks a way to resolve various issues associated with the application of this model. MCDM is a formal and systematic decision making approach that evaluates a given set of alternatives against a given set of criteria. The global evaluation of alternatives is determined through the process of aggregation. It is well established that the aggregation process should consider the importance of criteria while determining the overall worth of an alternative. The importance of individual criteria and of sub-sets of the criteria affects the global evaluation. The aggregation also needs to consider the importance of the sub-set of criteria. Most decision problems involve dependent criteria and the interaction between the criteria needs to be modelled. Traditional aggregation approaches, such as weighted average, do not model the interaction between the criteria. Non-additive measures such as fuzzy measures model the interaction between the criteria. However, determination of non-additive measures in a practical application is problematic. Various approaches have been proposed to resolve the difficulty in acquisition of fuzzy measures. These approaches mainly propose use of past precedents. This research extends this notion and proposes an approach based on similarity-based reasoning. Solutions to the past problems can be used to solve the new decision problems. This is the central idea behind the proposed methodology. The methodology itself applies the theory of reasoning by analogy for solving MCDM problems. This methodology uses a repository of cases of past decision problems. This case base is used to determine the fuzzy measures for the new decision problem. This work also analyses various similarity measures. The illustration of the proposed methodology in a case-based decision support system shows that interactive models are suitable tools for determining fuzzy measures in a given decision problem. This research makes an important contribution by proposing a similarity-based approach for acquisition of fuzzy measures.
292

An Agent-based hybrid framework for decision making on complex problems.

Zhang, Zili, mikewood@deakin.edu.au January 2001 (has links)
Electronic commerce and the Internet have created demand for automated systems that can make complex decisions utilizing information from multiple sources. Because the information is uncertain, dynamic, distributed, and heterogeneous in nature, these systems require a great diversity of intelligent techniques including expert systems, fuzzy logic, neural networks, and genetic algorithms. However, in complex decision making, many different components or sub-tasks are involved, each of which requires different types of processing. Thus multiple such techniques are required resulting in systems called hybrid intelligent systems. That is, hybrid solutions are crucial for complex problem solving and decision making. There is a growing demand for these systems in many areas including financial investment planning, engineering design, medical diagnosis, and cognitive simulation. However, the design and development of these systems is difficult because they have a large number of parts or components that have many interactions. From a multi-agent perspective, agents in multi-agent systems (MAS) are autonomous and can engage in flexible, high-level interactions. MASs are good at complex, dynamic interactions. Thus a multi-agent perspective is suitable for modeling, design, and construction of hybrid intelligent systems. The aim of this thesis is to develop an agent-based framework for constructing hybrid intelligent systems which are mainly used for complex problem solving and decision making. Existing software development techniques (typically, object-oriented) are inadequate for modeling agent-based hybrid intelligent systems. There is a fundamental mismatch between the concepts used by object-oriented developers and the agent-oriented view. Although there are some agent-oriented methodologies such as the Gaia methodology, there is still no specifically tailored methodology available for analyzing and designing agent-based hybrid intelligent systems. To this end, a methodology is proposed, which is specifically tailored to the analysis and design of agent-based hybrid intelligent systems. The methodology consists of six models - role model, interaction model, agent model, skill model, knowledge model, and organizational model. This methodology differs from other agent-oriented methodologies in its skill and knowledge models. As good decisions and problem solutions are mainly based on adequate information, rich knowledge, and appropriate skills to use knowledge and information, these two models are of paramount importance in modeling complex problem solving and decision making. Follow the methodology, an agent-based framework for hybrid intelligent system construction used in complex problem solving and decision making was developed. The framework has several crucial characteristics that differentiate this research from others. Four important issues relating to the framework are also investigated. These cover the building of an ontology for financial investment, matchmaking in middle agents, reasoning in problem solving and decision making, and decision aggregation in MASs. The thesis demonstrates how to build a domain-specific ontology and how to access it in a MAS by building a financial ontology. It is argued that the practical performance of service provider agents has a significant impact on the matchmaking outcomes of middle agents. It is proposed to consider service provider agents' track records in matchmaking. A way to provide initial values for the track records of service provider agents is also suggested. The concept of ‘reasoning with multimedia information’ is introduced, and reasoning with still image information using symbolic projection theory is proposed. How to choose suitable aggregation operations is demonstrated through financial investment application and three approaches are proposed - the stationary agent approach, the token-passing approach, and the mobile agent approach to implementing decision aggregation in MASs. Based on the framework, a prototype was built and applied to financial investment planning. This prototype consists of one serving agent, one interface agent, one decision aggregation agent, one planning agent, four decision making agents, and five service provider agents. Experiments were conducted on the prototype. The experimental results show the framework is flexible, robust, and fully workable. All agents derived from the methodology exhibit their behaviors correctly as specified.
293

Public Housing Tenant Relocation: Residential Mobility, Satisfaction, and the Development of a Tenant's Spatial Decision Support System.

Baker, Emma January 2002 (has links)
This study is an examination of residential mobility and its outcomes focussing on the forced relocation of public housing tenants from The Parks area of metropolitan Adelaide. In Euro-American countries, this type of residential mobility is increasingly used as a means of facilitating urban regeneration and countering the effects of the ongoing decrease in local public housing stock. The result is growing numbers of public tenants affected by relocation. The study agues that these public tenants have the right to a basic level of residential satisfaction, and in order for this satisfaction to be provided; the conditions and character of its formation must be understood. The thesis examines residential mobility and the formation of residential satisfaction to provide a basis for understanding the outcomes and effects of relocation, who is most affected, and how to target solutions to improve the relocation process. Despite the fact that households experience similar influences, and make their residential decisions in largely predictable ways, the formulation of residential satisfaction and the effects of relocation are highly individualised. Successful relocation is shown to be dependent on the inclusion of tenants' expert knowledge about their own residential satisfaction; this means that resident involvement in the process is crucial. This thesis investigates a means of combining these findings to improve the outcome of the relocation process for each individual tenant and their household. A prototype Spatial Decision Support System (SDSS) is constructed to allow relocating tenants to participate in their own relocation decision process. This SDSS allows local, spatially referenced information to be combined with each tenants own expert knowledge. This information is combined through a structured decision process, which is presented in a portable computer program with a simplified user interface. This SDSS is tested by relocating tenants and key stakeholders from The Parks to evaluate its usefulness in improving the relocation process. / Thesis (Ph.D.)--Geography and Environmental Studies, 2002.
294

Understanding and applying decision support systems in Australian farming systems research

Robinson, Jeffrey Brett, University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2005 (has links)
Decision support systems (DSS) are usually based on computerised models of biophysical and economic systems. Despite early expectations that such models would inform and improve management, adoption rates have been low, and implementation of DSS is now “critical” The reasons for this are unclear and the aim of this study is to learn to better design, develop and apply DSS in farming systems research (FSR). Previous studies have explored the merits of quantitative tools including DSS, and suggested changes leading to greater impact. In Australia, the changes advocated have been: Simple, flexible, low cost economic tools: Emphasis on farmer learning through soft systems approaches: Understanding the socio-cultural contexts of using and developing DSS: Farmer and researcher co-learning from simulation modelling and Increasing user participation in DSS design and implementation. Twenty-four simple criteria were distilled from these studies, and their usefulness in guiding the development and application of DSS were assessed in six FSR case studies. The case studies were also used to better understand farmer learning through models of decision making and learning. To make DSS useful complements to farmers’ existing decision-making repertoires, they should be based on: (i) a decision-oriented development process, (ii) identifying a motivated and committed audience, (iii) a thorough understanding of the decision-makers context, (iv) using learning as the yardstick of success, and (v) understanding the contrasts, contradictions and conflicts between researcher and farmer decision cultures / Doctor of Philosophy (PhD)
295

The antecedents of appropriate audit support system use

Dowling, Carlin Unknown Date (has links) (PDF)
This study investigates the factors that influence appropriate use of audit support systems. Appropriate use is use of an audit support system in a manner consistent with how the audit firm expects the system to be used. Investigating appropriate use of audit support systems is important because the extent to which these systems can assist auditors achieve efficient and high quality audits depends on how auditors use them. Adaptive Structuration Theory (AST) (DeSanctis and Poole, 1994) and the Theory of Planned Behaviour (TPB) (Ajzen, 1991) are combined to model the relationship between constructs hypothesised to increase the probability that audit support systems are used appropriately. The theoretical model decomposes two TPB antecedents, perceived normative pressure (or subjective norms) and perceived behavioural control, into the exogenous constructs hypothesised to influence whether audit support systems are used appropriately. Perceived normative pressure is decomposed into two socio-ideological control mechanisms, team and firm consensus on appropriation. Perceived behavioural control is decomposed into self-efficacy and two technocratic control mechanisms, perceived system restrictiveness and perceived audit review effectiveness. (For complete abstract open document)
296

Possibilities for the development of a decision support system for diagnosing heart failure

Olsson, Linda January 2007 (has links)
<p>Heart failure is a common disease which is difficult to diagnose. To aid physicians in diagnosing heart failure, a decision support system has been proposed. Parameters useful to the system are suggested. Some of these, such as age and gender, should be provided by the physician, and some should be derived from electro- and phonocardiographic signals.</p><p>Various methods of signal processing, such as wavelet theory and principal components analysis, are described. Heart failure should be diagnosed based on the parameters, and so various forms of decision support systems, such as neural networks and support vector machines, are described. The methods of signal processing and classification are discussed and suggestions on how to develop the system are made.</p>
297

protoBOM : Framework that semi-automatically generates Decision Support Systems based on Software Product Lines

Gomez Lacruz, Maria January 2008 (has links)
<p>This thesis presents the development of a prototype of the Baseline Oriented Modeling</p><p>(BOM) approach, called protoBOM.</p><p>BOM is a framework that semi-automatically generates Decision Support Systems in a</p><p>specific domain, based on Software Product Lines.</p><p>protoBOM semi-automatically generates applications as PRISMA architectural models by using Model-Driven Architecture and Software Product Line techniques. These models are automatically compiled and the object code (C#, in .NET) is generated obtaining an executable application.</p><p>In protoBOM, the user constructs Decision Support Systems in a simpler way by using the</p><p>ontologies of the diagnosis and the application domains by means of Domain Specific Languages. The interfaces will be closer to the problem domain, which will facilitate user interaction in a manner simple and intuitive.</p>
298

Automating pilot function performance assesssment using fuzzy systems and a genetic algorithm

Zaspel, Joachim C. 16 July 1997 (has links)
Modern civil commercial transport aircraft provide the means for the safest of all forms of transportation. While advanced computer technology ranging from flight management computers to warning and alerting devices contributed to flight safety significantly, it is undisputed that the flightcrew represents the most frequent primary cause factor in airline accidents. From a system perspective, machine actors such as the autopilot and human actors (the flightcrew) try to achieve goals (desired states of the aircraft). The set of activities to achieve a goal is called a function. In modern flightdecks both machine actors and human actors perform functions. Recent accident studies suggest that deficiencies in the flightcrew's ability to monitor how well either machines or themselves perform a function are a factor in many accidents and incidents. As humans are inherently bad monitors, this study proposes a method to automatically assess the status of a function in order to increase flight safety as part of an intelligent pilot aid, called the AgendaManager. The method was implemented for the capture altitude function: seeking to attain and maintain a target altitude. Fuzzy systems were used to compute outputs indicating how well the capture altitude function was performed from inputs describing the state of the aircraft. In order to conform to human expert assessments, the fuzzy systems were trained using a genetic algorithm (GA) whose objective was to minimize the discrepancy between system outputs and human expert assessments based on 72 scenarios. The resulting systems were validated by analyzing how well they conformed to new data drawn from another 32 scenarios. The results of the study indicated that even though the training procedure facilitated by the GA was able to improve conformance to human expert assessments, overall the systems performed too poorly to be deployed in a real environment. Nevertheless, experience and insights gained from the study will be valuable in the development of future automated systems to perform function assessment. / Graduation date: 1998
299

Development and comparison of two alternate display formats for an AgendaManager interface

Wilson, Robert B. (Robert Brian) 05 June 1997 (has links)
Modern commercial air travel is considered by most transportation specialists to be the safest of all forms of transportation. While safe, any loss of life is tragic and the only really acceptable state of commercial air transport safety is that of 'zero-tolerance' where no accident is acceptable. Research has demonstrated that the largest single causal component for airline accidents is the flightcrew. In addition, the recent automation of these machines has created many new safety concerns involving flightcrew situational awareness, human-machine interfacing, workload, attention, and complexity, to name a few. These concerns led to a series of studies developing, refining, and testing numerous aspects of this issue. The studies incorporated ASRS (Aviation Safety Reporting System) incident reports, NTSB (National Transportation Safety Board) and other accident reports, and the development of a CTM (cockpit task management) system. The information gained from this research led to the development of an agent-based cockpit task aiding system termed the AgendaManager. A traditional text-based display similar to that used in the CTMS study was developed, optimized, and integrated with existing systems like EICAS (Engine Indicating and Crew Alerting System) using a visual display development guide developed from a literature review. An alternate display incorporating graphics and located on the primary flight display (PFD) was also developed in an effort to improve pilot agenda management performance. Both of the interfaces were developed using a comprehensive visual display design guide compiled through a literature review. The Agenda Manager displays were tested in order to determine if the PFD enhancements improved agenda management performance. Eleven general aviation pilots participated in the study, three in the pilot study and eight in the main study. Results from the main study indicate little, if any, difference in agenda management performance in regards to the display format used. In general, the study demonstrated the usefulness of the display guidelines, importance of tracking instrument rating when using general aviation pilots in an experiment, and the equivalence of 'round-trip' scenarios. / Graduation date: 1998
300

Asset Levels of Service-based Decision Support System for Municipal Infrastructure Investment

Sharma, Vishal 06 1900 (has links)
The single biggest challenge facing municipalities today is a shortage of funds and labor for upgrading and expanding aging infrastructure. This continued lack of funding impairs the municipalities ability to maintain desired levels of service. Over the last decade, many Canadian municipalities have faced pressures of increasing complexity in infrastructure asset management decision-making which can be partly attributed to cost escalation, increasing service demand and interdependencies between networks. The goal of this research is to develop the framework for Asset Levels of Service (ALOS)-based decision support systems for municipal infrastructure network investment. The proposed framework is based on the fact that ALOS should be one of the main criteria for municipal infrastructure maintenance, repair and rehabilitation (MR&R). Since ALOS is based on qualitative and quantitative parameters, the use of ALOS in municipal infrastructure MR&R decisions will result in improved funding allocation. Secondary parameters used for municipal infrastructure investment decision making in the proposed framework are the physical deterioration of assets, future growth and the impact on the dependent infrastructure network. The proposed framework focuses on funding allocation for the MR&R of municipal networks. The framework is applicable to municipal infrastructure networks, excluding the other assets such as buildings, parks, etc. Application of the proposed framework is demonstrated by its implementation in the case of urban roads. Implementation is carried out in four phases. Phase I involves the quantification of ALOS for urban roads. Quantification of ALOS for urban roads has various challenges such as multiple users and interdependencies of levels of services between various users. An Analytical Hierarchy Process (AHP) has been used to quantify ALOS. Phase II involves the determination of a multiattribute utility function for investment decision. Calculated multiattribute utility of investment decision is used in the multiobjective optimization model in Phase III. In Phase IV, the proposed methodology is incorporated into a computer application called OPTIsys (OPTImum Infrastructure SYStems). OPTIsys will facilitate MR&R decision making based on fully integrated considerations of ALOS, future demand and network interdependencies. Stakeholders benefiting from OPTIsys include the general public, asset-managers, infrastructure departments and municipal councils. OPTIsys will enable infrastructure departments to maintain the operational capability of the network in compliance with the targeted levels of service. Overall, municipalities will be able to reduce the infrastructure deficit while maximizing economic returns. / Construction Engineering and Management

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