The Generalized Constraint Language (GCL), introduced by Zadeh, is the essence of Computing with Words (CW). It provides an genda to represent the meaning of imprecise words and phrases in natural language and introduces advanced techniques to perform reasoning on imprecise knowledge. Despite its fundamental role, the definition of GCL has remained informal since its introduction by Zadeh and, to our knowledge, no attempt has been made to formalize GCL or to build a working GCL deduction system. In this dissertation, two main interrelated objectives are pursued: First, the syntax and semantics of GCL are formalized in a logical setting. The notion of soundness of a GCL argument is defined and Zadeh's inference rules are proven sound in the defined language. Second, a CW Expert System Shell (CWSHELL) is implemented for the realization of a GCL deduction system. The CWSHELL software allows users to express their knowledge in terms of GCL formulas and pose queries to a GCL knowledge base. The richness of GCL language allows CWSHELL to greatly surpass current fuzzy logic expert systems both in its knowledge representation and reasoning capabilities. While many available fuzzy logic toolboxes can only represent knowledge in terms of fuzzy-if-then rules, CWShell goes beyond simple fuzzy conditional statements and performs a chain of reasoning on complex fuzzy propositions containing generalized constraints, fuzzy arithmetic expressions, fuzzy quantifiers, and fuzzy relations. To explore the application of CWSHELL, a realistic case study is developed to compute the auto insurance premium based on an imprecise knowledge base. The alpha version of CWSHELL along with the case study and documentation is available for download at http://cwjess.cs.siu.edu/.

Spatial decision making is a process of providing an effective solution for a problem that encompasses semi-structured spatial data. It is a challenging task which involves various factors to consider. For example, in order to build a new industry, an appropriate site must be selected for which several factors have to be taken into consideration. Some of the factors, which can affect the decision in this particular case, are air pollution, noise pollution, and distance from living areas, which makes the decision difficult. The geographic information systems (GIS) and the expert systems (ES) have many advantages in solving problems in their prospective areas. Integrating these two systems will benefit in solving spatial decision making problems. In the past, many researchers have proposed integrating systems which extracts the data from the GIS and saves it in the database for decision making. Most of the frameworks which have been developed were system dependent and are not properly structured. So it is difficult to search the data. This thesis proposes a framework which extracts the GIS data and processes it with the help of ES decision making capabilities to solve the spatial decision making problem. This framework is named GeoFilter. This research classifies various types of mechanisms that can be used to integrate these two systems.

Dans cette thèse, nous fournissons un examen complet des technologies du Web sémantique et de leurs utilités dans le contexte actuel des petites et moyennes entreprises (PME). Les approches traditionnelles d'intégration des entreprises favorisent essentiellement les grandes entités. Les obligations contractuelles fortes sur les PME, mais en même temps leur volonté de garder leurs compétences individuelles, et ce, dans un environnement limitant leur choix, les obligent à prendre des décisions stratégiques et de conclure des accords sur le long terme avec leurs partenaires, limitant ainsi leur flexibilité aux fluctuations du marché. Nous proposons, donc, une approche ontologique basée sur Web sémantique pour l'intégration de l'information ainsi que des ressources matérielles de l'entreprise distribuée. Cette approche, basée sur le Web, agit comme un système d'aide à la décision pour utiliser des ressources de meilleure qualité ainsi que pour l'intégration de l'information distribuée. Les travaux relatifs à l'ontologie web, pour l'intégration d'information ne sont pas nouveaux, mais l'approche proposée par nous est une valeur ajoutée pour l'entreprise distribuée. De plus, nous avons également proposé l'ontologie Web sémantique comme un système de configuration pour gérer les ressources distribuées de l'entreprise virtuelle. Puis, nous avons modélisé l'ontologie OWL-DL en nous basant sur la sémantique de la norme ISA-95, relative à l'intégration d'entreprises industrielles. Ensuite, nous utilisons cet artefact ontologique comme un artefact de configuration permettant de gérer le matériel de l'entreprise virtuelle distribuée ainsi que les ressources matérielles. C'est la proposition principale de cette thèse : utiliser l'ontologie Web sémantique comme un système d'aide à la décision pour la configuration de l'utilisation des ressources / In this thesis, we have provided a complete review of the semantic web technologies and their corresponding utility in the current environment for small to medium sized enterprise (MSE). The traditional approaches to enterprise integration favour large enterprise entities and force contractual limitations on smaller partners, but at the same time the pressure to guard the individual enterprise competence is ever increasing, the distributed enterprise (MSE) in such an environment have limited number of choices, which forces them to make strategic decisions and enter into a long term agreements with their partners and this limits their flexibility to the market changes. We, in this thesis, propose a semantic web based ontology approach for integrating the information as well as physical resource of the distributed enterprise. This web based approach acts as a decision support for better resources utility as well as distributed information integration. The work related to web ontology?s for information integration is not new, but the approach proposed in this thesis for distributed enterprise is an added value. Similarly, we have also proposed semantic web ontology as a configuration system to manage the distributed resources of the virtual enterprise, for this we have modelled OWL-DL ontology on the semantic of the industrial integration standard ISA-95, and subsequently used this ontology artefact as a configuration artefact to manage the distributed virtual enterprise material and equipment resources this is the main proposition of the thesis of utilizing semantic web ontology as resource configuration decision support

"A Single Function Agent (SiFA) is a software agent, with only one function, one point of view, and one target object on which to act. For example, an agent might be a critic (function) of material (target) from the point of view of cost. This research investigates the possibilities and implications of the SiFA concept, and analyzes the definition language, negotiation language and negotiation strategies of the agents. After defining a domain-independent set of agent types we investigated negotiation, analyzing which pairs/groups of agents have reason to communicate, and what the information passed between them should be, as well as what knowledge was needed to support the negotiation. A library for the CLIPS expert system shell was built, which allows development of SiFA based expert systems from domain independent templates. We will present two such systems, one as implemented for the domain of ceramic component material selection and the other (in development) for simple sailboat design. The effect of negotiation on the design process and the results are discussed, as well as directions for future research into SiFAs."

Digital educational technology is capable of contributing supplementary strategies that can be used to address various educational challenges faced by higher education. Foremost among these challenges is the widespread lack of academic preparedness of students who enter South African higher education institutions. The legacy of Apartheid, teachers' poor domain knowledge and command of the language of instruction, together with a lack of commitment to the cognitive development of learners are some of the reasons why students have not developed the cognitive skills required to engage in meaningful learning. Meaningful learning requires a high level of conceptual engagement and development. To assist in the learning process, educators must focus on student learning rather than on the instructor and the technology used in the instruction. A powerful means of supporting meaningful learning is through a process of model building. Computer technology can effectively be used to facilitate the building of conceptual models. By encouraging students to use computer technology to build models that represent their personal understanding, the students are performing the role of designer and the technology is used as a cognitive tool. Using digital technology as a cognitive tool allows students to engage in critical thinking and higher-order learning. An expert system shell is one way in which technology can be used as a cognitive tool. When students build expert systems they are required to demonstrate the reasoning of an expert and to exhibit an understanding of causal relationships and procedural knowledge. There is very little evidence of research concerning the application of expert systems as a cognitive tool in education. The primary aim of this study is to formulate design principles in the form of conjectures and principles related to a learning environment that uses technology as a cognitive tool in the form of an expert system shell to promote higher-order thinking skills. The second aim of this study is to explore the experiences of students who are exposed to a learning environment based on the conjectures and principles formulated during the design phase of the research. The conjectures and principles formulated during this study are expressed in terms of the characteristics, procedures and arguments associated with a learning environment that uses technology in the form of an expert system shell to facilitate higher-order thinking. These conjectures and principles were separated into seven interrelated clusters that can be summarised as follows: <ul><li> initial exposure;</li><li> guided discovery learning;</li><li> designing the expert system on paper;</li><li> creating domain awareness;</li><li> linking conceptual understanding to a representation of that understanding;</li><li> hands-on development; and</li><li> problem engagement.</il></ul> These conjectures and principles could guide similar endeavours undertaken by lecturers or instructional designers. / Thesis (PhD)--University of Pretoria, 2012. / Science, Mathematics and Technology Education / unrestricted