Adaptive systems are systems whose characteristics evolve over time to improve their performance at a task. A fairly new area of study is that of adaptive rule-based systems. The system studied for this thesis uses meta-knowledge about rules, rulesets, rule performance, and system performance in order to improve its overall performance in a problem domain. An interesting and potentially important phenomenon which emerged is that the performance the system learns while solving a problem appears to be limited by an inherent break-even level of complexity. That is, the cost to the system of acquiring complexity does not exceed its benefit for that problem. If the problem is made more difficult, however, more complexity is required, the benefit of complexity becomes greater than its cost, and the system complexity begins increasing, ultimately to the new break-even point. There is no apparent ultimate limit to the complexity attainable.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / It can be challenging to select the best architecture for DSP filters for a given application. Design constraints often include both objective and subjective information. This paper discusses the initial results of an investigation into using expert system techniques to address this problem. The goal is a system that allows users to specify traditional constraints such as impulse response, frequency response, stability, SNR, etc., but they may also constrain the filter’s cost, complexity, or any parameter which can be clearly identified for the specific application.

This thesis explores the extent to which forensic archaeology and forensic anthropology are utilised within Great Britain and to what extent they aid, or do not aid, medico-legal investigation of death. Chapter One introduces the topic and considers the need for an exploration of these issues. In Chapter Two, the differences between the American and British situations are examined and an explanation for the differences proposed, based on the development of the academic ‘parent’ disciplines during the last century. Chapter Three explores issues around accreditation and registration in the UK. The role of the courts in maintaining standards of expert evidence is examined. National and European schemes are considered. After considering the practitioners in this way, Chapter Four looks at the methods, and how the practitioners’ experience informs their choice of method. One specific topic for each discipline is discussed in depth and the complexity of choice illustrated. The difficulty in assessing the full scope for use of forensic archaeology and forensic anthropology are detailed in Chapter Five, with the marked lack of available research data. The problems inherent in media-derived data are considered. The scope for use of the two disciplines is discussed and illustrated with examples from the Media Derived Case List In Chapter Six, a complex multiple-burial multiple-murder case is discussed; and interviews across one police force area are discussed. These illustrate the use and usefulness of forensic archaeology in practice. Conclusions are drawn in Chapter Seven, and radical recommendations are made.

International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California / During early manned spacecraft operations, the primary role of ground telemetry systems was data display to flight controllers. As manned spaceflights have increased in complexity, greater demands have been placed on flight controllers to simultaneously monitor systems and replan systems operations. This has led to interest in automated telemetry monitoring systems to decrease the workload on flight controllers. The Mission Operations Directorate at the Lyndon B. Johnson Space Center has developed a five layer model to integrate various monitoring and analysis technologies such as digital filtering, fault detection algorithms, and expert systems. The paper describes the five layer model and explains how it has been used to guide prototyping efforts at Mission Control. Results from some initial expert systems are presented. The paper also describes the integrated prototype currently under development which implements a real time expert system to assist flight controllers in the Mission Control Center in monitoring Space Shuttle communications systems.

The application of Bayesian networks within the field of institutional research is explored through the development of a Bayesian network used to predict first- to second-year retention of undergraduates. A hybrid approach to model development is employed, in which formal elicitation of subject-matter expertise is combined with machine learning in designing model structure and specification of model parameters. Subject-matter experts include two academic advisors at a small, private liberal arts college in the southeast, and the data used in machine learning include six years of historical student-related information (i.e., demographic, admissions, academic, and financial) on 1,438 first-year students. Netica 5.12, a software package designed for constructing Bayesian networks, is used for building and validating the model. Evaluation of the resulting model’s predictive capabilities is examined, as well as analyses of sensitivity, internal validity, and model complexity. Additionally, the utility of using Bayesian networks within institutional research and higher education is discussed. The importance of comprehensive evaluation is highlighted, due to the study’s inclusion of an unbalanced data set. Best practices and experiences with expert elicitation are also noted, including recommendations for use of formal elicitation frameworks and careful consideration of operating definitions. Academic preparation and financial need risk profile are identified as key variables related to retention, and the need for enhanced data collection surrounding such variables is also revealed. For example, the experts emphasize study skills as an important predictor of retention while noting the absence of collection of quantitative data related to measuring students’ study skills. Finally, the importance and value of the model development process is stressed, as stakeholders are required to articulate, define, discuss, and evaluate model components, assumptions, and results.

International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Expert systems can be of great benefit to analysts, mission controllers, and flight safety officers who must make real-time decisions based upon a myriad of quickly changing parameters. Operators may require extensive training to view a limited parameter set or they can be aided by computers systematically monitoring many parameters. But, even today’s powerful general purpose computers and workstations are limited in their capabilities to monitor (i.e., process) the desired number of parameters. Thus, applications are distributed across multiple platforms. A telemetry ground station front end system (i.e., a real-time data server) that distributes preprocessed data to multiple knowledge stations over standard communications networks is presented.

No description available.

No description available.

published_or_final_version / Surveying / Doctoral / Doctor of Philosophy

published_or_final_version / Business Administration / Master / Master of Business Administration