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This thesis is a study of three techniques to improve performance of some standard fore-casting models, application to the energy demand and prices. We focus on forecasting demand and price one-day ahead. First, the wavelet transform was used as a pre-processing procedure with two approaches: multicomponent-forecasts and direct-forecasts. We have empirically compared these approaches and found that the former consistently outperformed the latter. Second, adaptive models were introduced to continuously update model parameters in the testing period by combining ?lters with standard forecasting methods. Among these adaptive models, the adaptive LR-GARCH model was proposed for the fi?rst time in the thesis. Third, with regard to noise distributions of the dependent variables in the forecasting models, we used either Gaussian or Student-t distributions. This thesis proposed a novel algorithm to infer parameters of Student-t noise models. The method is an extension of earlier work for models that are linear in parameters to the non-linear multilayer perceptron. Therefore, the proposed method broadens the range of models that can use a Student-t noise distribution. Because these techniques cannot stand alone, they must be combined with prediction models to improve their performance. We combined these techniques with some standard forecasting models: multilayer perceptron, radial basis functions, linear regression, and linear regression with GARCH. These techniques and forecasting models were applied to two datasets from the UK energy markets: daily electricity demand (which is stationary) and gas forward prices (non-stationary). The results showed that these techniques provided good improvement to prediction performance.

Learning (CAL) by the computing industry, there remained a shortage of suitable titles in some subject areas, including engineering. Investigation revealed that the most significant barrier to the exploitation of multimedia technology concerned justification and payback for the substantial amount of development effort required to produce software of this kind. It was found that the size of the potential audience for a programme was all too easily limited by the exorbitant computer system requirements and limited flexibility which tended to be built into the software by default. It was aimed to investigate whether the elements of a multimedia programme which contributed greatly to its computer system requirements, cost and inflexibility were so closely linked to its educational effectiveness. The research was experimental in nature. It involved the creation of several pieces of multimedia software, this being an experiment in itself since it allowed measurement of the amount of effort required to incorporate the various media into an educational programme. Two particularly significant pieces of software are described in detail in the thesis; an advisory system meant to promote design for testability among electronic engineers, and a CAL system offering an introduction to process planning. Both of these featured, in places, a highly interactive style, involving the dynamic generation of images and animations in response to users’ input. This represented a radical departure from the conventional approach to multimedia, which was normally based upon the sequential playback of prerecorded material. The process planning software was used with groups of students; their comments were invited and their performance was measured in a test which used a novel method to identify any students who had prior knowledge of the subject. (Correct answers from such people could not reasonably be claimed to indicate that learning had taken place, but the results of the remaining students provided a more accurate sample.) Knowing how well students had performed on each question, when taught in a variety of different styles, it was possible to compare the educational effectiveness of each approach. Since the amount of time spent adding each feature and medium to the software was known, it was then possible to identify which media had been the most efficient. It was found that interactivity is the most vital single ingredient in CAL software. Experimental results clearly showed that learning was most likely to occur when the subjects were required to play an active role. Attractive, informative media such as photographs and diagrams did generally help to facilitate learning, but the effect of these was comparatively minor. The author theorises that effective computer-based education does not necessarily involve extensive use of high quality digital video and the like; rather that the means to effective computer-based learning predate the multimedia era.

Over the past decade, a growing number of organisations have been developing executive information systems (EIS) to enhance the performance of their executive managers and facilitate their work. Such systems cannot improve individual and organisational performance if they aren't used. Thus, understanding the key determinants of EIS utilisation is an essential step toward enhancing their impact on individual users and organisational performance. Numerous case studies and explorative surveys of EIS development and implementation have been conducted, but an extensive literature review has shown that theory-based systematic investigations of post implementation use of EIS are rare, especially in the UK. The study reported here developed and tested a model of EIS usage. The proposed model integrates key constructs from the information systems success factors research stream into the theoretical frame of the technology acceptance model and other theories from social psychology (the theory of reasoned action, the theory of planned behaviour, and the Triandis model of attitude and behaviour). According to the proposed model, EIS usage is determined by six independent variables, namely perceived usefulness, perceived ease of use, information quality, involvement, subjective norm and facilitating conditions. In turn, perceived usefulness is influenced by perceived ease of use, perceived information quality, user involvement, subjective norm, and facilitating conditions. User involvement, perceived information quality and perceived ease of use are determined by four external factors, namely, user participation, information systems maturity, computer training, and user experience. The model was tested against data from 216 EIS users across various organisations. The results provided considerable support to the research model. In order of importance, subjective norm, perceived usefulness, facilitating conditions, information quality, and ease of use were found to explain 47.1% of the variance in EIS use. User involvement, information quality, subjective norm, ease of use, and facilitating conditions were found to explain 47.6% of the variance in perceived usefulness. Length of EIS use and computer use skill were found to explain 9% of the variance in perceived ease of use. IS maturity and user participation were found to explain 11% of the variance in EIS information quality. Finally, user participation was found to explain 2.4% of the variance in involvement. Implications of the study findings for practitioners and researchers are outlined.

The minerals industry often requires people to work in hazardous environments, these environments are constantly increasing in size and complexity as organisations look for new more cost-effective ways of extracting resources. Not only does this size and complexity bring with it additional safety concerns, the introduction of new legislation has placed the responsibility of employee safety with the organisation. Safety has become an important consideration, where once it might have been viewed as costly and counterproductive, organisations are now seeking to gain competitive advantage in this area. Two key areas of a successful safety management programme are risk assessment and training. These are important in designing systems and environments that are as safe as possible and in educating and training personnel to operate safely within those environments. Virtual Reality (VR) technology is one tool that has been applied successfully to the training requirements across a wide range of industries. In the past two years there is evidence to show that VR technology is becoming more widely used, partly due to the reduced cost and a reduction in the perceived technological complexity. As the cost of computing falls and the fidelity of the virtual worlds increases, VR is considered a viable option for a number of applications. Two prototype VR systems were designed and built. The first, a risk visualisation system, enhances a virtual environment with a risk-based overlay. The relationships between dangerous areas and equipment can be visualised in 3D. It also provides a framework for evaluating the risk programmatically at an arbitrary location. The second is a surface mine simulator that uses a hazard identification system as a tool to aid the training of haul truck operators in surface mine. This system includes a world construction tool that allows users to import and prepare the terrain, construct the virtual world, and specify any hazards. The training system can evaluate the performance of a trainee in the virtual world using a simple scoring algorithm.

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