This thesis deals with one important aspect of Artificial Intelligence, knowledge representation and reasoning. Problems like knowledge representation hypothesis, production systems, and the proceduralist and declarativist controversy are discussed. The conventional concept of Al system is based on a model where the reasoning and knowledge base are separate. A different model is proposed in this thesis. In this model, the sensory knowledge is considered the basic elements of the knowledge base, and the higher level knowledge form a hierarchical structure. Reasoning power, in this model, is only part of the, knowledge structure. A frame-based knowledge representation system, WenLy, is presented. It is designed to construct a knowledge base from the bottom up, which is conformed to the proposed model in this thesis. The unique characteristic of WenLy is that its reasoning is accomplished by the code imbedded in the knowledge base instead of a separate inference engine. This is the correct approach according to the knowledge structure model herein proposed. An example of the application is shown. WenLy can be used by a robot to represent the robot's understanding of the outside world. The understanding, however, is limited by the bandwidth of the perception capabilities. It can be shown that the conflict between the declarative and procedural aspects of knowledge can be resolved by following the proposed model.

In Corpus Based Knowledge Representation [CBKR], limited association capability, that is, no criteria in place to extract substantial associations in the corpus, and lack of support for hypothesis testing and prediction in context, restricted the application of the methodology by information specialists and data analysts. In this thesis, the researcher proposed a framework called CBKR+ to increase the expressiveness of CBKR by identifying and incorporating association criteria to allow the support of new forms of analyses related to hypothesis testing and prediction in context. <br /><br /> As contributions of the CBKR+ framework, the researcher (1) defined a new domain categorization model called Basis for Categorization model, (2) incorporated the Basis for Categorization model to (a) facilitate a first level categorization of the schema components in the corpus, and (b) define the Set of Criteria for Association to cover all types of associations and association agents, (3) defined analysis mechanisms to identify and extract further associations in the corpus in the form of the Set of Criteria for Association, and (4) improved the expressiveness of the representation, and made it suitable for hypothesis testing and prediction in context using the above. <br /><br /> The application of the framework was demonstrated, first, by using it on examples from the CBKR methodology, and second, by applying it on 12 domain representations acquired from multiple sources from the physical-world domain of Criminology. The researcher arrived at the conclusion that the proposed CBKR+ framework provided an organized approach that was more expressive, and supported deeper analyses through more diagnostic and probability-based forms of queries.

Thesis (Ph. D.)--University of Kentucky, 2001. / Title from document title page. Document formatted into pages; contains vii, 121 p. : ill. Includes abstract. Includes bibliographical references (p. 116-119).

Thesauri have been important information and knowledge organisation tools for more than three decades. The recent emergence and phenomenal growth of the World Wide Web has created new opportunities to introduce thesauri as information search and retrieval aids to end user communities. While the number of web-based and hypertextual thesauri continues to grow, few investigations have yet been carried out to evaluate how end-users, for whom all these efforts are ostensibly made, interact with and make use of thesauri for query building and expansion. The present paper reports a pilot study carried out to determine the extent to which a thesaurus-enhanced search interface to a web-based database aided end-users in their selection of search terms. The study also investigated the ways in which users interacted with the thesaurus structure, terms, and interface. Thesaurus-based searching and browsing behaviours adopted by users while interacting with the thesaurus-enhanced search interface were also examined.

Knowledge organization and concepts, knowledge organization as information policy, groupings as discoveries and constructions, semantics and its "warrant", structural linguistics, compositional semantics and semantic primitives, and universal solutions along with limitations are discussed in a series of 42 slides. "The most important conclusion, ... is that different "paradigms" or conceptualizations in the discourses should be made visible and semantic tools should support the navigation not just between "topics" but also between "views" and interests. If such information is made explicit it might improve the possibilities for internationalization because nobody's vital interests are then threatened." A reference list (of seven references) is included.

A major challenge faced by users during the information search and retrieval process is the selection of search terms for query formulation and expansion. Thesauri are recognised as one source of search terms which can assist users in query construction and expansion. As the number of electronic thesauri attached to information retrieval systems has grown, a range of interface facilities and features have been developed to aid users in formulating their queries. The pilot study reported here aimed to explore and evaluate how a thesaurus-enhanced search interface assisted end-users in selecting search terms. Specifically, it focused on the evaluation of users' attitudes toward both the thesaurus and its interface as tools for facilitating search term selection for query expansion. Thesaurus-based searching and browsing behaviours adopted by users while interacting with a thesaurus-enhanced search interface were also examined

Despite the many clear advantages that ontology has to offer as a standardized knowledge representation language, many intelligent system developers still find it difficult to jump on the band wagon and represent all their application knowledge using ontology. This difficulty and hesitation stems primarily from the fact that, while most ontology languages provide native support for reasoning about the domain's structures, they do not provide adequate support for computational planning -- the kind of reasoning used by many intelligent systems to derive their purposeful behaviors. To overcome this challenge, a lot of work has been done to discover a practical way to seamlessly incorporate planning into ontology languages. As it has been well-established in the literature however, this is a very challenging task from both a theoretical and practical stand point, and many of the reported works in this direction either have had very limited success, or have been done in ad hoc and less reusable manners. In this thesis, we report our pursuit of a new approach to integrating planning into ontology-driven applications. This approach promises to overcome the difficulties faced by many of the existing approaches. In addition to producing a reusable and extensible framework for doing computational planning in ontology-driven applications, our pursuit also raises and answers some interesting ontology research questions that could have potential impacts on several application domains beyond the integration of planning and ontological modeling.

Concept mapping in college-level physics was investigated. The study was carried out in three parts. First, an attempt was made to validate concept mapping as a method of evaluating student learning at the junior college level (ages 16-21). Several measures were found to be sensitive to differences in students' achievement. Second, the effectiveness of concept mapping as an instructional strategy was investigated. It was found that the strategy led to improvement in multistep problem-solving performance but not in performance on single step problems. Third, the concept maps made by experts in the field were compared with the maps made by high achieving and average achieving students to see if this is yet another way in which high performance and expertise are related. It was found that the high achieving students made maps which more nearly resembled the maps made by experts than those made by average achieving students.

The starting point for this research was the belief that interactive multimedia learning environments represent a significant evolution in computer based learning and therefore their design requires a re-examination of the underlying principles of learning and knowledge representation. Current multimedia learning environments (MLEs) can be seen as descendants of the earlier technologies of computer-aided learning (CAL), intelligent tutoring systems (ITS) and videodisc-based learning systems. As such they can benefit from much of the wisdom which emerged from those technologies. However, multimedia can be distinguished from earlier technologies by its much greater facility in bringing to the learner high levels of interaction with and control over still and moving image, animation, sound and graphics. Our intuition tells us that this facility has the potential to create learning environments which are not merely substitutes for &quot;live&quot; teaching, but which are capable of elucidating complex conceptual knowledge in ways which have not previously been possible. If the potential of interactive multimedia for learning is to be properly exploited then it needs to be better understood. MLEs should not just be regarded as a slicker version of CAL, ITS or videodisc but a new technology requiring a reinterpretation of the existing theories of learning and knowledge representation. The work described in this thesis aims to contribute to a better understanding of the ways in which MLEs can aid learning. A knowledge engineering approach was taken to the design of a MLE for civil engineers. This involved analysing in detail the knowledge content of the learning domain in terms of different paradigms of human learning and knowledge representation. From this basis, a design strategy was developed which matched the nature of the domain knowledge to the most appropriate delivery techniques. The Cognitive Apprenticeship Model (CAM) was shown to be able to support the integration and presentation of the different categories of knowledge in a coherent instructional framework. It is concluded that this approach is helpful in enabling designers of multimedia systems both to capture and to present a rich picture of the domain. The focus of the thesis is concentrated on the domain of Civil Engineering and the learning of concepts and design skills within that domain. However, much of it could be extended to other highly visual domains such as mechanical engineering. Many of the points can also be seen to be much more widely relevant to the design of any MLE.

Research on the deciphering of nonsense words within the context of text, a story, or tale was conducted at various schools and day-care centres in the Stirling area of Scotland in 1985-1988. Three experiments were conducted, in which large samples of primary school children aged 4-12 were tested. The experiments resembled Werner and Kaplan's (1950) &quot;Word-Context Task, &quot; in which isolated sentences in a series with one nonsense word in each sentence were presented to school children. The children were asked to answer questions about the meanings of these words. The results were not in line with the rapid word learning that experience suggests happens in young children, it was not until after age 9 that the children started to give approximately correct answers, and prior to age 11 the answers did not meet up with proper adult definitions. It has been pointed out, however (Donaldson, 1978), that because these sentences were not supported by any relation to immediate context and behaviour, and because the children were required to process utterances as pure isolated language - an unnatural situation for language acquisition - the &quot;Word-Context Task&quot; may have given an unrealistic picture of the child's ability to acquire language naturally. In the three word-leaming studies at Stirling University in 1985-1988, in order to account for a more natural presentation, the sentences with the nonsense word were embodied in the context of a story. Children were thought to fare better (than the children in the Wemer &amp; Kaplan study) when listening to such a story, especially if the basic theme was of interest. A methodological tool, refined in the work of Dockrell (1981), in which the full meaning of a term involves having worked out the sense, reference, and denotation of the term. was applied in each of the test batteries that followed the presentation of the story. In these tests, the children were tested on both their comprehension and production of the new term in question. Drawings were used in order to try to tap the children's denotation of the new term, and to facilitate young children's approach to the demands of the study. As regards word meaning in general. Martin Joos (1972) had argued that the common blunder was that an odd word must have an odd sense--the odder, the better. He argued that one should define words in such a fashion as to make them contribute least to the total message derivable from its passage where it is housed, rather than, e. g., defining it according to some presumed etymology of semantic history. He called this concept &quot;a tacit principle&quot;, and argued that word learners and word users would sense the intuitive familiarity of the conveyed meaning of words and text. Words are, according to this principle, &quot;mysterious&quot; in their environment, their meanings are not worked out deliberately, intentionally; rather, one should make the mysterious item maximally supportive and supported in its situation, in order that redundancy would result in proper connotation of the distributed meaning. Context and knowledge of contexts reveal meaning; the text is processed holistically, and so are the instantaneous meanings of the words of which it is composed. Thus, Joos maintained that in deciphering an unknown word, the wisest course is to assume the &quot;least meaning&quot; consistent with the context. Tasks such as Werner and Kaplan's &quot;Word-Context Task&quot; (1950), force subjects to infer aspects of meaning that go well beyond this &quot;least&quot; meaning and, as Joos pointed out, this leads notably to errors from which recovery is difficult. In the studies at Stirling University, attempts were made to determine if different types of learning would result in different types of responses. The dichotomy, intentional/incidental or analytic/holistic was worked out into experimental and control conditions, as based on Aveling's pioneering experiment (1911, 1912) into the general and particular aspects of encoded stimuli. Later, Lee Brooks (1978) worked with the dichotomies intentional/incidental in his Lepton experiments and argued that the more complex a behaviour is (speaking or writing, for example), the more likely it is to be learned implicitly. He pointed out, however, that the dichotomies explicit/implicit, analytic/non analytic, and deliberate vs. intuitive processes need to be elaborated and not taken as a strict division. In the three experiments at Stirling, children of primary school age (ages 4 to 12) were presented with a &quot;word-context&quot; task and their understanding of the unknown word was probed under different conditions. In the control condition a control word was probed, but in the experimental condition the child's understanding of the target word was fully tested. All the children listened to a short story displayed by a video or read from a tape in which the unknown word occurred in several different contexts, the unknown word in each story denoted an unfamiliar natural kind. During the story's display, children in the control condition were, at certain intervals, asked questions about the story's theme. Children in the experimental group were, at these same intervals, shown a sample of objects, to one of which the unknown word referred, and they were asked to hand these objects to the experimenter as she requested the objects, or they were asked direct questions about the meaning of the target word and about other words in the story. After hearing the story, all subjects were tested on their comprehension and production of the unknown word, together with other words, and a scoring procedure based on a technique developed by Dockrell (1981) was applied. This procedure necessitated the full meaning of the term covering aspects of the sense, reference., and denotation of the new term (cf. Lyons, 1977a). The results indicate that children younger than those tested in the Wemer and Kaplan's &quot;Word-Context Task&quot; (ages 8.6 to 13.6) could decipher the full meaning of the new term. But individual differences within age groups showed greater differences than existed between age groups. All in all, the results indicate that working out the full meaning of a new term is a lengthy process indeed (Campbell &amp; Dockrell, 1986), even though a sense of the given semantic domain may often be established quite early in the learning process. Performance styles also differ from younger children to older ones. The results indicate that there were significant age differences between the children in the first and second experiments, but that such differences were lacking in the third experiment, and that control subjects in the three studies seldom gave poorer responses than did experimental subjects and often did better. However, the results must be interpreted in the light of learning and recovery from error occurring, within the experimental subjects in the course of deciphering. If the initial scores of the experimental subjects on the target word as obtained during encoding are compared with the first scores obtained from the control subjects after they had heard the whole story, there is a significant difference in scores between the conditions in favour of the control subjects in all age groups. This is consistent with Joos's assumption that an interference concerning the meaning of a word that occurs too early in the learning task and not enough information of contextual cues will lead the children in the experimental groups astray in their guesses when asked too early for answers on the new word's meaning. But implied in Joos's Axiom is the likelihood for recoveries from errors, and the strategies children use in order to work them out need to be explored further. Much individual variation was found among the children's responses in the age groups. These differences were indeed more significant than were the differences between age groups.