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An Investigation Of Residual Stresses Induced By Forming Processes On The Fatigue Resistance Of Automotive Wheels, Patrick James Mcgrath Jan 2001

An Investigation Of Residual Stresses Induced By Forming Processes On The Fatigue Resistance Of Automotive Wheels, Patrick James Mcgrath

School of Engineering, Computing and Mathematics Theses

The nature and scope of this thesis relates to obtaining an understanding of the way in which sheet metal forming processes affect the residual stresses (plastic deformation) and the fatigue perfomiance of wheel centre discs made of a dual phase steel. Automotive wheels are mainly manufactured from sheet metal plate by forming processes using tools and dies. This manufacturing process is directly concemed with deforming the plate under predominantly applied tensile forces where the component acquires a sfress state which is multi-axiial. This stress state is both complex and difficult to assess from an analytical point of view and thus …

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The Application Of Real-Time Software In The Implementation Of Low-Cost Satellite Return Links, James Tom Slader Jan 2001

The Application Of Real-Time Software In The Implementation Of Low-Cost Satellite Return Links, James Tom Slader

School of Engineering, Computing and Mathematics Theses

Digital Signal Processors (DSPs) have evolved to a level where it is feasible for digital modems with relatively low data rates to be implemented entirely with software algorithms. With current technology it is still necessary for analogue processing between the RF input and a low frequency IF but, as DSP technology advances, it will become possible to shift the interface between analogue and digital domains ever closer towards the RF input. The software radio concept is a long-term goal which aims to realise software-based digital modems which are completely flexible in terms of operating frequency, bandwidth, modulation format and source …

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Natural Algorithms In Digital Filter Design, Stephen Penberthy Harris Jan 2001

Natural Algorithms In Digital Filter Design, Stephen Penberthy Harris

School of Engineering, Computing and Mathematics Theses

Digital filters are an important part of Digital Signal Processing (DSP), which plays vital roles within the modern world, but their design is a complex task requiring a great deal of specialised knowledge. An analysis of this design process is presented, which identifies opportunities for the application of optimisation. The Genetic Algorithm (GA) and Simulated Annealing are problem-independent and increasingly popular optimisation techniques. They do not require detailed prior knowledge of the nature of a problem, and are unaffected by a discontinuous search space, unlike traditional methods such as calculus and hill-climbing. Potential applications of these techniques to the filter …

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Improving Design And Administration Of Government Support Programmes For Industry, Ronald Crayden Downing Jan 2001

Improving Design And Administration Of Government Support Programmes For Industry, Ronald Crayden Downing

School of Engineering, Computing and Mathematics Theses

This thesis describes the research which has been undertaken into a particular area of policy making in the UK, that of the process of designing and implementing programmes aimed at helping industrial firms to become more competitive. Investigations have focused on how the design process is conducted within the Department of Trade and Industry (DTI), which has lead responsibility for industry in Whitehall. The research had Uvo primary aims. First was to provide a detailed description of the process of designing programmes. Based on the research findings it is proposed that the process comprises the components of'Issue Identification', 'Programme Implementation', …

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Modelling Business Processes With Links To Iso 9001, Joachim Gingele Jan 2001

Modelling Business Processes With Links To Iso 9001, Joachim Gingele

School of Engineering, Computing and Mathematics Theses

This work in the domain of quality management and business process design looks at how the requirements of the ISO 9001 standard for quality management systems are designed and implemented in business. It is the aim of the research reported in this thesis to support manufacturing companies when modelling a Fulfil Order Process by identifying the links to the ISO 9001 quality standard and highlighting potential impact from any changes in the process or the standard during a redesign project. It does so by presenting a modelling technique, named IDEF9000, which will enable companies to take a systemic perspective of …

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A Model For Managing Information Flow On The World Wide Web, Michael Paul Evans Jan 2001

A Model For Managing Information Flow On The World Wide Web, Michael Paul Evans

School of Engineering, Computing and Mathematics Theses

This thesis considers the nature of information management on the World Wide Web. The web has evolved into a global information system that is completely unregulated, permitting anyone to publish whatever information they wish. However, this information is almost entirely unmanaged, which, together with the enormous number of users who access it, places enormous strain on the web's architecture. This has led to the exposure of inherent flaws, which reduce its effectiveness as an information system. The thesis presents a thorough analysis of the state of this architecture, and identifies three flaws that could render the web unusable: link rot; …

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Process-Property-Fabric Architecture Relationships In Fibre-Reinforced Composites, Neil Robert Lewarne Pearce Jan 2001

Process-Property-Fabric Architecture Relationships In Fibre-Reinforced Composites, Neil Robert Lewarne Pearce

School of Engineering, Computing and Mathematics Theses

The use of fibre-reinforced polymer matrix composite materials is growing at a faster rate than GDP in many countries. An improved understanding of their processing and mechanical behaviour would extend the potential applications of these materials. For unidirectional composites, it is predicted that localised absence of fibres is related to longitudinal compression failure. The use of woven reinforcements permits more effective manufacture than for unidirectional fibres. It has been demonstrated experimentally that compression strengths of woven composites are reduced when fibres are clustered. Summerscales predicted that clustering of fibres would increase the permeability of the reinforcement and hence expedite the …

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Investigation Into Digital Audio Equaliser Systems And The Effects Of Arithmetic And Transform Errors On Performance, Robin John Clark Jan 2001

Investigation Into Digital Audio Equaliser Systems And The Effects Of Arithmetic And Transform Errors On Performance, Robin John Clark

School of Engineering, Computing and Mathematics Theses

Discrete-time audio equalisers introduce a variety of undesirable artefacts into audio mixing systems, namely, distortions caused by finite wordlength constraints, frequency response distortion due to coefficient calculation and signal disturbances that arise from real-time coefficient update. An understanding of these artefacts is important in the design of computationally affordable, good quality equalisers. A detailed investigation into these artefacts using various forms of arithmetic, filter frequency response, input excitation and sampling frequencies is described in this thesis. Novel coefficient calculation techniques, based on the matched z-transform (MZT) were developed to minimise filter response distortion and computation for on-line implementation. It was …

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Women's Employment In Bangladesh Agriculture: Composition, Determinants And Scope, S Rahman Oct 2000

Women's Employment In Bangladesh Agriculture: Composition, Determinants And Scope, S Rahman

School of Geography, Earth and Environmental Sciences

Gender composition of labour use and factors determining demand and supply of female labour in crop production is examined using survey data from 14 villages in two agro-ecological regions of Bangladesh. The share of women in labour use ranges between 11-18% in foodgrain (rice and wheat) and 14-48% in non-cereal (highest for vegetables) production. Incidence of female labour hire is very low and varies directly with land size classes while supply from family varies inversely. Cultivation of diverse crops (local and modern varieties of rice, jute, oilseeds and vegetables), education as well as women's ownership of land increases demand for …

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A Holistic Approach To The Evaluation Of Socio-Economic And Environmental Impacts Of Technological Change In Agriculture: An Application In Bangladesh, S Rahman, Jk Routray Jul 2000

A Holistic Approach To The Evaluation Of Socio-Economic And Environmental Impacts Of Technological Change In Agriculture: An Application In Bangladesh, S Rahman, Jk Routray

School of Geography, Earth and Environmental Sciences

No abstract provided.

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Guanylyl Cyclase Activity Associated With Putative Bifunctional Integral Membrane Proteins In Plasmodium Falciparum, Dj Carucci, Aa Witney, Dk Muhia, Dc Warhurst, Et Al Jul 2000

Guanylyl Cyclase Activity Associated With Putative Bifunctional Integral Membrane Proteins In Plasmodium Falciparum, Dj Carucci, Aa Witney, Dk Muhia, Dc Warhurst, Et Al

School of Biomedical Sciences

We report here that guanylyl cyclase activity is associated with two large integral membrane proteins (PfGCalpha and PfGCbeta) in the human malaria parasite Plasmodium falciparum. Unusually, the proteins appear to be bifunctional; their amino-terminal regions have strong similarity with P-type ATPases, and the sequence and structure of the carboxyl-terminal regions conform to that of G protein-dependent adenylyl cyclases, with two sets of six transmembrane sequences, each followed by a catalytic domain (C1 and C2). However, amino acids that are enzymatically important and present in the C2 domain of mammalian adenylyl cyclases are located in the C1 domain of the P. …

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The Bloom's Syndrome Gene Product Promotes Branch Migration Of Holliday Junctions, Jk Karow, A Constantinou, J-L Li, Sc West, Id Hickson Jun 2000

The Bloom's Syndrome Gene Product Promotes Branch Migration Of Holliday Junctions, Jk Karow, A Constantinou, J-L Li, Sc West, Id Hickson

School of Biomedical Sciences

Bloom's syndrome (BS) is an autosomal recessive disorder associated with dwarfism, immunodeficiency, reduced fertility, and elevated levels of many types of cancer. BS cells show marked genomic instability; in particular, hyperrecombination between sister chromatids and homologous chromosomes. This instability is thought to result from defective processing of DNA replication intermediates. The gene mutated in BS, BLM, encodes a member of the RecQ family of DExH box DNA helicases, which also includes the Werner's syndrome gene product. We have investigated the mechanism by which BLM suppresses hyperrecombination. Here, we show that BLM selectively binds Holliday junctions in vitro and acts on …

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From Robotic Toil To Symbolic Theft: Grounding Transfer From Entry-Level To Higher-Level Categories1, A Cangelosi, A Greco, S Harnad Jun 2000

From Robotic Toil To Symbolic Theft: Grounding Transfer From Entry-Level To Higher-Level Categories1, A Cangelosi, A Greco, S Harnad

School of Engineering, Computing and Mathematics

Neural network models of categorical perception (compression of within-category similarity and dilation of between-category differences) are applied to the symbol-grounding problem (of how to connect symbols with meanings) by connecting analogue sensorimotor projections to arbitrary symbolic representations via learned category-invariance detectors in a hybrid symbolic/non-symbolic system. Our nets are trained to categorize and name 50 × 50 pixel images (e.g. circles, ellipses, squares and rectangles) projected on to the receptive field of a 7 × 7 retina. They first learn to do prototype matching and then entry-level naming for the four kinds of stimuli, grounding their names directly in the …

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Pesticide Demand Among Hybrid Vegetable And Cereal Seed Producers In Bangladesh: A Simultaneous Equation Analysis, S Rahman, Mz Hossain Jun 2000

Pesticide Demand Among Hybrid Vegetable And Cereal Seed Producers In Bangladesh: A Simultaneous Equation Analysis, S Rahman, Mz Hossain

School of Geography, Earth and Environmental Sciences

Demand for pesticides, inorganic and organic fertilizers were jointly estimated using survey data from a randomly selected 81 BRAC ‘contract hybrid vegetables and cereal seed growers’ in northwestern Bangladesh applying a simultaneous equation framework. Pesticide cost accounts for 6.9% of the gross value of output in hybrid seeds of vegetables and 3.2% in cereals. About 87% of farmers used pesticides at least once with mean number of application of 4.4 times. Twenty-seven brands of pesticides were used including a substantial number of banned pesticides. Price elasticity of demand for pesticides, fertilizers and biofertilizers were estimated at –0.83, –0.21 and –1.13, …

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Molecular Cloning Of A Gene Encoding A 20s Proteasome Β Subunit From Plasmodium Falciparum, G-D Li, J-L Li, M Mugthin, Sa Ward May 2000

Molecular Cloning Of A Gene Encoding A 20s Proteasome Β Subunit From Plasmodium Falciparum, G-D Li, J-L Li, M Mugthin, Sa Ward

School of Biomedical Sciences

A novel gene was cloned from Plasmodium falciparum. Database searches indicated this gene to be a member of the 20S proteasome beta-subunit family. Comparison of the gene's genomic DNA sequence with cDNA sequence revealed a 156-bp intron 85 bp downstream from the start codon. The nucleotide sequence of the gene contains one open reading frame encoding 265 amino acids with a predicted molecular mass of 30.9 kDa and a pI of 6.2. Northern blot analysis showed the transcript size to be approximately 1.6 kb indicating that some 800 bp of the transcript is non-coding.

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Managerial Decisions: A Discursive Analysis, Teresa Ann Mcconville Apr 2000

Managerial Decisions: A Discursive Analysis, Teresa Ann Mcconville

Plymouth Business School Theses

Decision making activity is at the heart of organisations and, as an essential managerial function, it has been the subject of an immense body of literature. As the majority of research has been undertaken within the disciplines of economics and psychology, studies have tended to emphasise economic rationality as the basis for cognitive reasoning, decision processes and judgement and as the analytic paradigm. However, in the face of new problems, and in times of profound change, conventional forms of thought may be problematic in themselves. This project suggests and assesses a Foucaultian framework as an alternative approach to the study …

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Sexual Stage-Specific Expression Of A Third Calcium-Dependent Protein Kinase From Plasmodium Falciparum, J-L Li, Da Baker, Ls Cox Apr 2000

Sexual Stage-Specific Expression Of A Third Calcium-Dependent Protein Kinase From Plasmodium Falciparum, J-L Li, Da Baker, Ls Cox

School of Biomedical Sciences

A third calcium-dependent protein kinase (CDPK) gene has been isolated from the human malaria parasite Plasmodium falciparum by vectorette technology. The gene consists of five exons and four introns. The open reading frame resulting from removal of the four introns encodes a protein of 562 amino acid residues with a predicted molecular mass of 65.3 kDa. The encoded protein, termed PfCDPK3, consists of four distinct domains characteristic of a member of the CDPK family and displays the highest homology (46% identity and 69% similarity) to PfCDPK2, the second CDPK of P. falciparum. The N-terminal variable domain is rich in serine/threonine …

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Ecological Risk Assessment Of Endocrine Disruptors, Th Hutchinson, R Brown, Ke Brugger, Pm Campbell, M Holt, R Länge, P Mccahon, Lj Tattersfield, Egmond R Van Jan 2000

Ecological Risk Assessment Of Endocrine Disruptors, Th Hutchinson, R Brown, Ke Brugger, Pm Campbell, M Holt, R Länge, P Mccahon, Lj Tattersfield, Egmond R Van

School of Geography, Earth and Environmental Sciences

No abstract provided.

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A Molecular Approach To Calanus (Copepoda:Calanoida) Development And Systematics, Penelope Kate Lindeque Jan 2000

A Molecular Approach To Calanus (Copepoda:Calanoida) Development And Systematics, Penelope Kate Lindeque

School of Biological and Marine Sciences Theses

Production and recruitment measurements in marine copepods of the genus Calanus have been addressed via the study of genes involved in early embryogenesis. The first sequence from a Calanus helgolandicus (C. helgolandicus) developmental gene (Cal-Antp) has been cloned by screening a C. helgolandicus genomic library with a homologous Calanus homeobox probe. Sequencing of an isolated and sub-cloned fragment of this gene, plus further analysis by Inverse Polymerase Chain Reaction (IVPCR), has shown it to be homologous with other Antennapedia homeobox genes. The temporal expression of Cal-Antp was analysed through its messenger RNA (mRNA) complement by Reverse Transcription Polymerase Chain Reaction …

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Spatial And Seasonal Variation In The Performance Of Algorithms For Deriving In-Water Properties From Ocean Colour, Anthony Guy Westbrook Jan 2000

Spatial And Seasonal Variation In The Performance Of Algorithms For Deriving In-Water Properties From Ocean Colour, Anthony Guy Westbrook

School of Biological and Marine Sciences Theses

The on-going calibration and validation of visible satellite imagery remains a core activity of the scientific community in pursuit of high quality data characterising the oceanic chlorophyll field, providing input to models assessing primary productivity and the potential role of the oceans in climatic regulation. This work serves to examine the operational characteristics of semi-analytical algorithms that are designed to derive key optical properties from space born observations of ocean colour. The collection of water samples contemporaneously with precision profiled radiometry conforming to similar spectral bands to those of the NASA Sea Viewing Wide Field of view Sensor (SeaWiFS) was …

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From Rivers To Oceans: A Comparison Of Contrasting Aquatic Ecosystems Using Benthic Size Spectra, Ahmed El-Sayed Ahmed Abada Jan 2000

From Rivers To Oceans: A Comparison Of Contrasting Aquatic Ecosystems Using Benthic Size Spectra, Ahmed El-Sayed Ahmed Abada

School of Biological and Marine Sciences Theses

This thesis uses a range of different size spectra to compare contrasting benthic habitats in the aquatic realm. Temporal and spatial variation in benthic size spectra were investigated across a full salinity gradient (i.e. from freshwater, through estuarine to marine) in the River Yealm, south Devon, in order to gauge the influence of large differences in taxonomy and evolutionary history. Abundance and biomass size spectra showed a similar pattern among sites in all seasons but winter, suggesting that the size structure of benthic communities may be similar in sites with very different community compositions. A subsequent study comparing size spectra …

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Determination Of Larval Fish Survival From Feeding And Distribution Observations, David Vernon Pollock Conway Jan 2000

Determination Of Larval Fish Survival From Feeding And Distribution Observations, David Vernon Pollock Conway

School of Biological and Marine Sciences Theses

The series of papers round which this thesis is based highlight the inherent problems in assessing larval fish feeding success from sampling programmes and gut contents analysis, and show through novel observations, that counting the number of food items in the gut is not necessarily a good indication of feeding success. Food type, digestibility and size, gut passage rates and the particular lipid classes the food contains, must all be considered, illustrating the difficulties in interpreting larval fish energetics from field studies. The resistance to digestion demonstrated for copeped eggs, means that a potentially rich source of energy cannot be …

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Large-Scale Temporal And Spatial Patterns Of Marine Phytoplankton In The North-East Atlantic, Martin Edwards Jan 2000

Large-Scale Temporal And Spatial Patterns Of Marine Phytoplankton In The North-East Atlantic, Martin Edwards

School of Biological and Marine Sciences Theses

Phytoplankton constitute the main algal biomass in pelagic ecosystems and, therefore, play a fundamental role in the functioning of the marine trophic web. Information on long-term trends in marine phytoplankton may help to distinguish between biological responses to natural oscillations in climate and global warming, and to evaluate possible regional effects of eutrophication. The aim of this work was to contribute to the general understanding of how phytoplankton are spatio-temporally structured at the large-scale. To achieve this aim, the Continuous Plankton Recorder (CPR) survey data were used to identify the dominant large-scale spatial patterns of phytoplankton in north-western European continental …

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Dynamics Of A Small Tidal Estuarine Plume, Mark Pritchard Jan 2000

Dynamics Of A Small Tidal Estuarine Plume, Mark Pritchard

School of Biological and Marine Sciences Theses

Small-scale estuarine plume discharges into adjacent seas are common inshore features responsible for the transportation and dispersion of brackish water in the coastal zone. However, the physics that govern small-scale mixing in the frontal regions of river plumes are still poorly understood. The current study quantified and compared the observed hydrodynamic properties present inside a radially spreading river plume discharge from the River Teign, Teignmouth, Devon, UK, to those predicted by a generic plume model. Numerical simulations designed to replicate time dependent radial plume spreading from a constant source predicted the development of an internal interfacial bore that lagged the …

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Development Of The Random Amplified Polymorphic Dna (Rapd) Technique To Measure The Effects Of Genotoxinsin Aquatic Organisms, Franck Andre Atienzar Jan 2000

Development Of The Random Amplified Polymorphic Dna (Rapd) Technique To Measure The Effects Of Genotoxinsin Aquatic Organisms, Franck Andre Atienzar

School of Biological and Marine Sciences Theses

Studies were undertaken to evaluate the potential of random amplified polymorphic DNA (RAPD) to detect DNA effects (including DNA damage and mutations) in aquatic invertebrates, following their exposure to a variety of environmental contaminants under laboratory conditions. After rigorous optimisation of the RAPD method, the protocol, which used a high annealing temperature (50"C for 10-mer primers), was found to generate good-quality DNA profiles from groups of organisms belonging to the bacterial, plant and animal kingdoms. The RAPD method was initially used to detect benzo(a)pyrene [B(a)P] and copper-induced DNA effects in the water flea Daphnia magna and ultraviolet-mediated DNA effects in …

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Spatial Variation In Zooplankton Size And Taxonomic Community Structure Along A 50ºn To 50°S Transect Of The Atlantic, Rachel Sarah Woodd-Walker Jan 2000

Spatial Variation In Zooplankton Size And Taxonomic Community Structure Along A 50ºn To 50°S Transect Of The Atlantic, Rachel Sarah Woodd-Walker

School of Biological and Marine Sciences Theses

Zooplankton play a vital role in the world's oceans in terms of transport of carbon out of the surface layer and providing food for fish. Zooplankton are patchily distributed on all scales, and this has important consequences for both sampling and understanding their role in the ocean. The distribution of zooplankton on different scales forms the focus of this study. Three Atlantic Meridional Transect (AMT) cruises were carried out and data made available from three previous cruises. Zoo plankton data were collected using a combination of vertical nets and using an optical plankton counter (OPC) sampling from the pumped seawater …

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An Evaluation Of The Use Of Spectral Properties In Monitoring Stress In Marine Macroalgae, Sarah Jane May Jan 2000

An Evaluation Of The Use Of Spectral Properties In Monitoring Stress In Marine Macroalgae, Sarah Jane May

School of Biological and Marine Sciences Theses

The overall aim of this thesis was to assess the potential of developing specific quantifiable assays of pollutant damage based on changes on the in vivo optical properties of macroalgae, applicable to laboratory and remote systems. The green macroalgae, E.intestinalis, was exposed to selected trace metals (copper and zinc), triazine herbicides (Irgarol 1051 and atrazine) and a series of alcohols (n = 1 - 9). The algal in vivo spectral properties, measured using a spectrophotometer fitted with an integrating sphere, determined changes due to exposure, and results were compared with established methods, including growth and fluorescence, to assess algal health …

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Models Of Oxidative Stress Induced By Disease Or Pollution In Invertebrates And Vertebrates, Heather Clare Meigh Jan 2000

Models Of Oxidative Stress Induced By Disease Or Pollution In Invertebrates And Vertebrates, Heather Clare Meigh

School of Biological and Marine Sciences Theses

Glutathione and its related enzymes have a central role in the antioxidant mechanisms of both invertebrates and vertebrates. Evidence suggests that changes in antioxidant defence mechanisms are associated with the late complications of diabetes. In addition, invertebrates show changes in antioxidant mechanisms in response to contamination; these changes have the potential to be utilised in the environmental monitoring of pollution. The present study investigated the role of glutathione and its related enzymes with regard to complications of diabetes and toxicity exposure using the crab, Carcinus maenas. A preliminary investigation showed that glutathione peroxidase and glutathione reductase activities are unaltered in …

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Investigation Into The Feasibilty Of Providing Intelligent Support For Computer Mediation Decision Making Groups, Andrew Martyn Morley Jan 2000

Investigation Into The Feasibilty Of Providing Intelligent Support For Computer Mediation Decision Making Groups, Andrew Martyn Morley

School of Psychology Theses

This thesis investigated the claim that the adaptation to the keyboard interface of a computer-mediated (CM) decision making group leads to differences in the style of communication when compared to that of a face-to-face (FTF) group. More importantly it examined the possibility that changes in satisfaction with the process and the decision outcome are determined not by the mode of communication, but rather the style of communication the decision makers employed in response to the keyboard interface. The decision processes of CM and FTF groups were examined using a simulated panel of enquiry presented via computer databases and containing inconsistent …

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A Generic Approach, Employing Information Systems, For Introducing Manufacturing Information Systems In Sme 'S, Zahoor Ahmed Qurashi Jan 2000

A Generic Approach, Employing Information Systems, For Introducing Manufacturing Information Systems In Sme 'S, Zahoor Ahmed Qurashi

School of Engineering, Computing and Mathematics Theses

This thesis presents an approach which the small and medium size firms can use in-house to introduce manufacturing information systems. The approach developed is generic and employs information system design and analysis techniques to guide Small and Medium size Enterprises (SME's) from specification of their need, right through to the implementation of an appropriate solution. Although there are various tools and methodologies that are available for large organisations needs, none are available for SME's. Therefore, the approach presented in this thesis provides original and significant improvements on current practice. The approach emphasises the importance of taking a company wide approach …

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