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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.
21

Enhanced database system for active design modelling

Baig, Anwar January 1999 (has links)
No description available.
22

An expert system for slope stability assessment

Brown, D. J. January 1988 (has links)
No description available.
23

Second generation knowledge based systems in habitat evaluation

Cain, Mark January 1993 (has links)
Many expert, or knowledge-based, systems have been constructed in the domain of ecology, several of which are concerned with habitat evaluation. However, these systems have been geared to solving particular problems, with little regard paid to the underlying relationships that exist within a biological system. The implementation of problem-solving methods with little regard to understanding the more primary knowledge of a problem area is referred to in the literature as 'shallow', whilst the representation and utilisation of knowledge of a more fundamental kind is termed 'deep'. This thesis contains the details of a body of research exploring issues that arise from the refinement of traditional expert systems methodologies and theory via the incorporation of depth, along with enhancements in the sophistication of the methods of reasoning (and subsequent effects on the mechanisms of communication between human and computer), and the handling of uncertainty. The approach used to address this research incorporates two distinct aspects. Firstly, the literature of 'depth', expert systems in ecology, uncertainty, and control of reasoning and related user interface issues are critically reviewed, and where inadequacies exist, proposals for improvements are made. Secondly, practical work has taken place involving the construction of two knowledge based systems, one 'traditional', and the other a second generation system. Both systems are primarily geared to the problem of evaluating a pond site with respect to its suitability for the great crested newt (Triturus cristatus). This research indicates that it is possible to build a second-generation knowledge-based system in the domain of ecology, and that construction of the second generation system required a magnitude of effort similar to the firstgeneration system. In addition, it shows that, despite using different architectures and reasoning strategies, such systems may be judged as equally acceptable by endusers, and of similar accuracy in their conclusions. The research also offers guidance concerning the organisation and utilisation of deep knowledge within an expert systems framework, in both ecology and in other domains that have a similar concept-rich nature.
24

Painless knowledge acquisition for time series data

Mitchell, F. January 1997 (has links)
Knowledge Acquisition has long been acknowledged as the bottleneck in producing Expert Systems. This is because, until relatively recently, the KA (Knowledge Acquisition) process has concentrated on extracting knowledge from a domain expert, which is a very time consuming process. Support tools have been constructed to help this process, but these have not been able to reduce the time radically. However, in many domains, the expert is not the only source of knowledge, nor indeed the best source of knowledge. This is particularly true in industrial settings where performance information is routinely archived. This information, if processed correctly, can provide a substantial part of the knowledge required to build a KB (Knowledge Base). In this thesis I discuss current KA approaches and then go on to outline a methodology which uses KD (Knowledge Discovery) techniques to mine archived time series data to produce fault detection and diagnosis KBs with <I>minimal expert input. </I>This methodology is implemented in the TIGON system, which is the focus of this thesis. TIGON uses archived information (in TIGON's case the information is from a gas turbine engine) along with <I>guidance</I> from the expert to produce KBs for detecting and diagnosing faults in a gas turbine engine. TIGON's performance is also analysed in some detail. A comparison with other related work is also included.
25

Learning of rule-based knowledge from inexact examples.

January 1990 (has links)
by Wong Man Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 200-206. / ABSTRACT --- p.A-1 / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Properties of an ideal AKARS --- p.4 / Chapter 1.3 --- The architecture of AKARS-1 --- p.9 / Chapter 1.4 --- Research approach --- p.13 / Chapter 2 --- state of the art of machine learning --- p.16 / Chapter 2.1 --- Learning by instruction --- p.16 / Chapter 2.2 --- Learning by analogy --- p.17 / Chapter 2.3 --- Learning from examples --- p.17 / Chapter 2.4 --- Learning from observation and discovery --- p.24 / Chapter 3 --- SESS: a Simple Expert System Shell --- p.26 / Chapter 3.1 --- Overview of SESS --- p.26 / Chapter 3.2 --- Knowledge representation --- p.27 / Chapter 3.2.1 --- Representation of attribute --- p.27 / Chapter 3.2.2 --- Representation of fuzzy concepts --- p.28 / Chapter 3.2.3 --- Representation of rules --- p.29 / Chapter 3.3 --- Reasoning in SESS --- p.31 / Chapter 3.3.1 --- Rule evaluation --- p.31 / Chapter 3.3.2 --- Rules with multiple antecedent conditions --- p.32 / Chapter 3.3.3 --- Calculation of certainty factor --- p.33 / Chapter 4 --- A prototypical learning component --- p.35 / Chapter 4.1 --- A prototypical Automatic Knowledge Acquisition System: AKA-1 --- p.35 / Chapter 4.1.1 --- Introduction to AKA-1 --- p.35 / Chapter 4.1.2 --- A generic rule learning algorithm --- p.37 / Chapter 4.1.3 --- Method for evaluating the discriminatory abilities --- p.43 / Chapter 4.1.4 --- Method for determining the best attribute/value pair --- p.44 / Chapter 4.1.4.1 --- Determining the best nominal attribute/value pair --- p.44 / Chapter 4.1.4.2 --- Determining the best structural attribute/value pair --- p.46 / Chapter 4.1.4.3 --- Determining the best linear attribute/value pair --- p.48 / Chapter 4.1.5 --- Method for calculating certainty factors of rules --- p.50 / Chapter 4.1.6 --- Rule inducing algorithm of AKA-1 --- p.50 / Chapter 4.2 --- Generalizing production rules --- p.51 / Chapter 4.2.1 --- Testing significance of condition --- p.52 / Chapter 4.2.1.1 --- Chi-squre test (Large sample test) --- p.53 / Chapter 4.2.1.2 --- Fisher-Irwin's exact test (Small sample test) --- p.54 / Chapter 4.2.2 --- The generalization algorithm --- p.55 / Chapter 4.3 --- Case studies --- p.55 / Chapter 4.3.1 --- Case one --- p.56 / Chapter 4.3.2 --- Case two --- p.59 / Chapter 4.3.3 --- Case three --- p.59 / Chapter 4.3.4 --- Comparison with ID3 --- p.60 / Chapter 5 --- inducing fuzzy rules from inexact examples --- p.62 / Chapter 5.1 --- Introduction to AKA-2 --- p.62 / Chapter 5.2 --- Notations --- p.63 / Chapter 5.3 --- Method for selecting attribute/value pairs in AKA-2 --- p.67 / Chapter 5.4 --- Evaluating certainty factors of rules --- p.72 / Chapter 6 --- HERES: a HEuristic REfinement System --- p.78 / Chapter 6.1 --- Introduction to HERES --- p.78 / Chapter 6.2 --- Refinement concepts of HERES --- p.79 / Chapter 6.2.1 --- Refinement operations --- p.80 / Chapter 6.2.2 --- Refinement phases of HERES --- p.81 / Chapter 6.2.3 --- Strategy for knowledge base refinement --- p.83 / Chapter 6.2.4 --- Refinement examples --- p.86 / Chapter 6.2.5 --- Performance statistics --- p.91 / Chapter 6.2.6 --- Rule statistics --- p.94 / Chapter 6.2.7 --- Summary of refinement concepts --- p.96 / Chapter 6.3 --- Logical structure of HERES --- p.98 / Chapter 6.4 --- Rule analysis --- p.101 / Chapter 6.4.1 --- Rule analysis for generalization --- p.101 / Chapter 6.4.1.1 --- For rules with non-fuzzy final conclusions --- p.101 / Chapter 6.4.1.2 --- For hierarchical rules with non-fuzzy final conclusion --- p.107 / Chapter 6.4.1.3 --- For rules with fuzzy final conclusions --- p.108 / Chapter 6.4.2 --- Rule analysis for specialization --- p.108 / Chapter 6.4.2.1 --- For rules with non-fuzzy final conclusions --- p.108 / Chapter 6.4.2.2 --- For rules with fuzzy conclusions --- p.111 / Chapter 6.5 --- Modification of rule statistics --- p.111 / Chapter 6.6 --- First order G-3 refinement --- p.117 / Chapter 6.7 --- Higher order G-S refinement --- p.120 / Chapter 6.8 --- Heuristics of HERES --- p.122 / Chapter 6.8.1 --- Notations --- p.123 / Chapter 6.8.2 --- Control heuristics --- p.124 / Chapter 6.8.3 --- Strategic heuristics --- p.126 / Chapter 6.8.3.1 --- Strategic heuristics for generalization --- p.127 / Chapter 6.8.3.2 --- Strategic heuristics for specialization --- p.127 / Chapter 6.8.4 --- Refinement heuristics --- p.128 / Chapter 6.8.4.1 --- Refinement heuristics for generalization --- p.128 / Chapter 6.8.4.2 --- Refinement heuristics for specialization --- p.131 / Chapter 6.9 --- Discussion --- p.132 / Chapter 7 --- Verification of AKARS-l --- p.134 / Chapter 7.1 --- Verification methodologies --- p.134 / Chapter 7.1.1 --- Existing examples methodology --- p.134 / Chapter 7.1.2 --- Existing knowledge base methodology --- p.135 / Chapter 7.2 --- Methods for evaluating the performance of a knowledge base --- p.141 / Chapter 7.2.1 --- First method (Successful rate method) --- p.141 / Chapter 7.2.2 --- Second method (MDCF method) --- p.145 / Chapter 7.3 --- Case studies --- p.149 / Chapter 7.3.1 --- Case one --- p.149 / Chapter 7.3.2 --- Case two --- p.152 / Chapter 7.3.3 --- Case three --- p.156 / Chapter 7.4 --- Verification results --- p.157 / Chapter 7.4.1 --- Results of case one --- p.157 / Chapter 7.4.1.1 --- First experiment --- p.157 / Chapter 7.4.1.2 --- Second experiment --- p.158 / Chapter 7.4.1.3 --- Discussion --- p.160 / Chapter 7.4.2 --- Results of case two --- p.162 / Chapter 7.4.2.1 --- First experiment --- p.162 / Chapter 7.4.2.2 --- Second experiment --- p.163 / Chapter 7.4.2.3 --- Third experiment --- p.165 / Chapter 7.4.2.4 --- Fourth experiment --- p.166 / Chapter 7.4.2.5 --- Discussion --- p.167 / Chapter 7.4.3 --- Results of case three --- p.169 / Chapter 7.5 --- Discussion --- p.172 / Chapter 8 --- Developing hierarchical knowledge bases --- p.173 / Chapter 8.1 --- Introduction --- p.173 / Chapter 8.2 --- Acquire hierarchical knowledge bases by using AKARS-1 --- p.176 / Chapter 8.2.1 --- Difficulties of inducing multiple-level rules --- p.176 / Chapter 8.2.2 --- Structural approach of building hierarchical knowledge bases --- p.179 / Chapter 8.3 --- Further improvement on AKARS-1 to induce hierarchical knowledge bases --- p.181 / Chapter 9 --- Conclusion --- p.182 / Appendix A --- p.186 / Appendix B --- p.187 / Appendix C --- p.188 / Appendix D --- p.193 / Appendix E --- p.194 / Reference --- p.200
26

An integrative fuzzy expert system shell based on structured knowledge: an object oriented approach.

January 1989 (has links)
by Wong Man Hon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 197-202.
27

A hybrid approach to knowledge representation for knowledge-based systems.

January 1988 (has links)
by Shu-kin Kwan. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 151-156.
28

Do expert systems impact taxpayer behavior?

Olshewsky, Steven J. 30 September 2004 (has links)
Individuals are increasingly using expert system tax programs as a substitute for paid professionals when preparing their income tax returns. This study examines ways that expert systems encourage the same aggressive results documented when paid professionals are used. Examining the use of expert systems and the related behavior of taxpayers reveals aggressive reporting related to the commonly used warning alerts in tax programs. Using an experimental economics setting in which participants report liabilities with the possibility of penalties for noncompliant reporting, participants filled out a Claim Form mimicking a Schedule C in one of four conditions: manual preparation, no alerts, alerts triggered at a high threshold of reporting aggression, and alerts triggered at a low level of reporting aggression. Comparing the amounts deducted in each condition revealed that warning alerts with low thresholds of activation decreased aggressive reporting while warning alerts with high thresholds of activation increased aggressive reporting. Survey instruments measuring user satisfaction indicated significantly lower satisfaction when (high or low level) warning alerts were used versus no warning alerts. Contrary to expectations, respondents using the expert system tax program with high threshold warning alerts compared to no warning alerts reported a significantly higher perception of accuracy. This study demonstrates the extreme to which taxpayers are swayed by perceived aspects of the tax software that are irrelevant to the facts of their tax situations. Exactly what taxpayers need to be given by way of guidance and direction to comport their behavior to the tax laws is a critical question of public policy.
29

Expertchefens ledarskap och utmaningar -en studie i tre naturvetenskapliga kontexter

Grebius, Magdalena January 2013 (has links)
Syftet med denna uppsats har varit att med kvalitativ metodik erhålla en fördjupad förståelse för relationen mellan expertis och ledarskap i chefsrollen. Jag har velat identifiera de för- och nackdelar som finns i denna kombination samt identifiera de strategier som finns för att hantera relationen. Detta har studerats genom nio intervjuer i tre naturvetenskapliga kontexter- statligt, akademi och privat. Analys av intervjumaterialet identifierade följande kategorier: Ledarskap- en outforskad terräng för experten, Expertkunskap krävs för ledarskapet, Ledarskapet är expertens karriärväg, Balansen mellan expert och ledare i chefsrollen samt För- och nackdelar med att vara expert och ledare. Resultaten visade att expertchefer förväntas prestera både som experter och ledare. De erhåller dock olika tysta signaler från sin omgivning om att expertisen står över ledarskapet. Frånvarande direktiv från ledningen hur chefen bör prioritera sin tid och sitt engagemang mellan sina roller gör att chefen väljer mellan tre strategier: att kombinera sitt ledarskap och sin expertroll eller lägga tyngden på antingen ledarskapet eller expertisen. Dessa strategier kan medföra olika effekter på ledarnas upplevda situation, medarbetares arbetssituation och verksamhetens arbetsklimat. Resultaten beskrevs i relation till tidigare forskning och Goodalls teori om expertledarskapets betydelse för ledarskapet. En avslutande diskussion fördes om resultaten i relation till syftet och frågeställningen.
30

Socialtjänstlagen i mötet : Socialarbetarens möjligheter för att stärka individens egna resurser / Social Services Act in the meeting : Social workers' opportunities to strengthen the indivisual's own resources

WM Pooya, Caroline, Östlund, Johanna January 2011 (has links)
The purpose of this study was to examine the resources and barriers that social workers have incorporating the Social Service Act states during meetings with clients, using and developing the client's skills and knowledge, develop their own resources and to promote the use of self-determination. A qualitative study was done by interviewing six social workers working within the in social service’s department for family and individual welfare. Social workers were encouraged to describe and discuss the key aspects of cases that developed positively respectively negatively. Motivation theory, evidence-based practice, empowerment, and expert-expert relationship are the theories and concepts that we used to analyze the material. The study's main conclusion is that the most important prerequisite for positive development of cases is that the social worker emphasizes and stimulates the client's own resources during meetings. Both during analysis and treatment, it is important to allow for client self-determination, life story and personal skill. When this occurs motivation and increased willingness to change are stimulated in the client. The results also paint a complex picture of resources and barriers, both within the social worker and the client, which affect the development of a case. The survey shows that motivation, self-determination, voluntariness, sustainability, time, resources and the strengthening of good relations is important factors for the incorporation of the Social Service Act states. / Syftet med denna studie var att undersöka socialarbetarens möjligheter att i mötet med klienter införliva socialtjänstlagens portalparagraf. En kvalitativ undersökning gjordes genom intervjuer av sex socialarbetare inom socialtjänstens individ- och familjeomsorg. Socialarbetarna uppmuntrades att beskriva och berätta om de viktigaste aspekterna i ett ärende som utvecklades positivt respektive negativt. Motivationsteori, evidensbaserad praktik, empowerment och expert- expert förhållande är de teorier och begrepp som vi använt för att analysera materialet.   Studiens främsta slutsats vad gäller positiv utveckling i ärenden är att socialarbetaren ska lyfta fram klientens resurser i mötet. Både i utredning och i behandling är det av vikt att ge utrymme för klientens självbestämmande, livsberättelse och kunskaper. Då detta sker skapas motivation och ökad förändringsbenägenhet hos klienten. Resultatet målar även upp en komplex bild av resurser och hinder hos socialarbetaren och klienten, som påverkar ett ärendes utveckling. Undersökningen visar att motivation, självbestämmande, frivillighet, långsiktighet, tid, stärkande av resurser och en god relation är viktiga faktorer för införlivandet av socialtjänstlagens portalparagraf.

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