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The Impact Of Rapido Trawling For Scallops, Pecten Jacobaeus (L.), On The Benthos Of The Gulf Of Venice, J. M. Hall-Spencer, C. Froglia, R. J.A. Atkinson, P. G. Moore Jan 1999

The Impact Of Rapido Trawling For Scallops, Pecten Jacobaeus (L.), On The Benthos Of The Gulf Of Venice, J. M. Hall-Spencer, C. Froglia, R. J.A. Atkinson, P. G. Moore

School of Biological and Marine Sciences

No abstract provided.

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Intelligent Control Strategies For An Autonomous Underwater Vehicle, Paul Jason Craven Jan 1999

Intelligent Control Strategies For An Autonomous Underwater Vehicle, Paul Jason Craven

School of Engineering, Computing and Mathematics Theses

The dynamic characteristics of autonomous underwater vehicles (AUVs) present a control problem that classical methods cannot often accommodate easily. Fundamentally, AUV dynamics are highly non-linear, and the relative similarity between the linear and angular velocities about each degree of freedom means that control schemes employed within other flight vehicles are not always applicable. In such instances, intelligent control strategies offer a more sophisticated approach to the design of the control algorithm. Neurofuzzy control is one such technique, which fuses the beneficial properties of neural networks and fuzzy logic in a hybrid control architecture. Such an approach is highly suited to …

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Reducing The Computational Effort Associated With Evolutionary Optimisation In Single Component Design, Harish Dhanji Vekeria Jan 1999

Reducing The Computational Effort Associated With Evolutionary Optimisation In Single Component Design, Harish Dhanji Vekeria

School of Engineering, Computing and Mathematics Theses

The dissertation presents innovative Evolutionary Search (ES) methods for the reduction in computational expense associated with the optimisation of highly dimensional design spaces. The objective is to develop a semi-automated system which successfully negotiates complex search spaces. Such a system would be highly desirable to a human designer by providing optimised design solutions in realistic time. The design domain represents a real-world industrial problem concerning the optimal material distribution on the underside of a flat roof tile with varying load and support conditions. The designs utilise a large number of design variables (circa 400). Due to the high computational expense …

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Advanced Magnetic Thin-Film Heads Under Read-While-Write Operation, Frank Zhigang Wang Jan 1999

Advanced Magnetic Thin-Film Heads Under Read-While-Write Operation, Frank Zhigang Wang

School of Engineering, Computing and Mathematics Theses

A Read-While-Write (RWW) operation for tape and/or potentially disk applications is needed in the following three cases: 1. High reliability; 2. Data servo systems; 3. Buried servo systems. All these applications mean that the read (servo) head and write head are operative simultaneously. Consequently, RWW operation will require work to suppress the so-called crossfeed field radiation from the write head. Traditionally, write-read crossfeed has been reduced in conventional magnetic recording heads by a variety of screening methods, but the effectness of these methods is very limited. On the other hand, the early theoretical investigations of the crossfeed problem concentrating on …

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Assessment Of The Effects Of Uv-B In Marine Macroalgae: Potential Biomarkers Of Exposure And Effect, Britt Cordi Jan 1999

Assessment Of The Effects Of Uv-B In Marine Macroalgae: Potential Biomarkers Of Exposure And Effect, Britt Cordi

School of Biological and Marine Sciences Theses

Studies were undertaken to investigate the suitability of several molecular and physiological responses as biomarkers of UV-B exposure in several marine macroalgal species. Investigations into the sensitivity of mature plants and the reproductive unicells were also carried out. Furthermore, experiments were conducted to determine the interaction between UV-B radiation and the antifouling compound Irgarol 1051 in both a fouling alga and two non-target algal species. Chlorophyll fluorescence, in vivo thallus absorptance and ion leakage were investigated for their suitability as physiological biomarkers of UV -B exposure in the intertidal alga Enteromorpha intestinalis and the subtidal alga Palmaria palmata. DNA damage …

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Dietary Interactions Influencing Feed Intake, Nutrient Utilisation And Appetite Regulation In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Tekinay Jan 1999

Dietary Interactions Influencing Feed Intake, Nutrient Utilisation And Appetite Regulation In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Tekinay

School of Biological and Marine Sciences Theses

Dietary factors are one of the most significant considerations in the regulation of appetite in fish since dietary nutrient and energy concentration modulate feed intake in the short and longer term. These interactions may also be important from a commercial aspect, since the objective of aquaculture is to obtain maximum growth, feed efficiency and consumer acceptance of the product. This thesis addresses the major dietary components which are likely to influence appetite in rainbow trout. These include dietary lipid level, carbohydrate content and degree of complexity as well as energy density and protein/energy ratio. Experimental data is presented which examines …

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Morphology And Electrophysiology Of Retinal Photoreceptor Terminations In The Octopus (Eledone Cirrosa) Optic Lobe, Dominic Anthony Hussey Jan 1999

Morphology And Electrophysiology Of Retinal Photoreceptor Terminations In The Octopus (Eledone Cirrosa) Optic Lobe, Dominic Anthony Hussey

School of Biological and Marine Sciences Theses

Cephalopods possess a well-developed visual system encompassing a pair of camera-type eyes attached to specific visual processing regions of the central nervous system known as the optic lobes. The retina contains a single type of photoreceptive cell, which send axons via a dorso-ventral chiasma to the optic lobes. Although electrophysiological recordings have been routinely obtained from the retina there are few recordings from the optic lobe. This study investigated the morphology and electrophysiology of the first synapse in the Octopus (Eledone cirrosa) visual system. The morphology and innervation patterns of individual optic nerves onto the optic lobe were revealed using …

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Mechanisms For The Formation Of Rhythmic Topography In The Nearshore Region, Giovanni Coco Jan 1999

Mechanisms For The Formation Of Rhythmic Topography In The Nearshore Region, Giovanni Coco

School of Biological and Marine Sciences Theses

The possibility that the periodic features observed in the nearshore region are the result of self-organisational processes is investigated in this work. The behaviour of two numerical models, based on different techniques, has been analysed in order to describe the formation of periodic features in the surf and swash zone respectively. The appearance of periodic patterns in the nearshore region has been traditionally linked to the presence of standing edge waves with the topographic changes passively driven by the flow patterns. A more recent approach indicates the possibility that periodic patterns appear because of feedback processes between beach morphology and …

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The Changing Face Of Policing: Local Issues In National Perspective, Philip Kessell Bunt Jan 1999

The Changing Face Of Policing: Local Issues In National Perspective, Philip Kessell Bunt

School of Law, Humanities and Social Sciences Theses

The thesis reviews the changes which have taken place in policing England and Wales between 1950 and 1998 with particular reference to foui* key themes: community policmg, crime preverition, victims of crime and quality ofservice. It contributes to ah understanding of how policing has developed during a period of significant social change and explores the rationale which has underpinned legislative development and policy making at national and force levels whilst identifying the significance of these changes within a local city environment. The development of the key themes at national level is considered within the local policing environment of the south-west …

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Optimization Of An Automated Fi-Ft-Ir Procedure For The Determination Of O-Xylene, Toluene And Ethyl Benzene In N-Hexane, I. Wells Jan 1999

Optimization Of An Automated Fi-Ft-Ir Procedure For The Determination Of O-Xylene, Toluene And Ethyl Benzene In N-Hexane, I. Wells

School of Geography, Earth and Environmental Sciences

The development and optimization of an automated flow injection (FI) manifold coupled with a Fourier transform infrared (FT-IR) detector for the determination of toluene, ethyl benzene and o-xylene in an n-hexane matrix is described. FT-IR parameters optimized were resolution and number of co-added scans; FI parameters optimized were type of pump tubing, carrier flow rate and sample volume. A TR and transmission flow cells were compared for the determination of o-xylene, the A TR cell was easier to use and gave better figures of merit, except for sensitivity, for which the transmission cell was twice as good. Multivariate calibration routines …

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A Submersible Battery-Powered Flow Injection (Fi) Sensor For The Determination Of Nitrate In Estuarine And Coastal Waters, Arj David, T Mccormack, Pj Worsfold Jan 1999

A Submersible Battery-Powered Flow Injection (Fi) Sensor For The Determination Of Nitrate In Estuarine And Coastal Waters, Arj David, T Mccormack, Pj Worsfold

School of Geography, Earth and Environmental Sciences

The design, construction and performance of a remotely deployed submersible flow injection-based nutrient (total oxidized nitrogen) sensor are described. The sensor featured a custom-built microcomputer and a solid-state, flow-through spectrophotometric detector, and the derivatization chemistry was based on in-line coppercadmium reduction of nitrate to nitrite, and diazotization with N1NED and sulphanilamide. The limit of detection was 0.0014 mg l-1 NO3-N and the linear range was 0.0014- 0.77 mg l-1 with a 260 μl sample volume and a 20 mm path length flow cell. Results from submersed deployments in the Tamar estuary and North Sea are also reported.

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The Use Of Isolators For Cytotoxic Handling In Hospital Pharmacies, Gj Sewell Jan 1999

The Use Of Isolators For Cytotoxic Handling In Hospital Pharmacies, Gj Sewell

School of Health Professions

Many issues elating to isolator use in hospital pharmacies are under debate, including the quality of the background environment, sanitisation of materials transferred into isolators, the use of positive or negative pressure isolators for cytotoxics, ergonomics and gaseous sterilisation. However, continuing improvement in isolator design, isolator monitoring and the understanding of isolator technology means that the use of these devices is now well established in the UK and is becoming increasingly widespread throughout mainland Europe.

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The Role Of The Pharmacist In Provision Of Hi-Tech Health-Care At Home, Gj Sewell, J Loader Jan 1999

The Role Of The Pharmacist In Provision Of Hi-Tech Health-Care At Home, Gj Sewell, J Loader

School of Health Professions

No abstract provided.

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Observations And Possible Function Of The Striking Anterior Coloration Pattern Of Galathea Intermedia (Crustacea: Decapoda: Anomura), J. M. Hall-Spencer, P. G. Moore, L. U. Sneddon Jan 1999

Observations And Possible Function Of The Striking Anterior Coloration Pattern Of Galathea Intermedia (Crustacea: Decapoda: Anomura), J. M. Hall-Spencer, P. G. Moore, L. U. Sneddon

School of Biological and Marine Sciences

No abstract provided.

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An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill Dec 1998

An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill

Peninsula Medical School

The increasing use of alternative crops has meant the introduction of new technologies to process their products. In this work, an alternative method is presented for the extraction of natural indigo from woad (Isatis tinctoria) based on a technique used to extract indigo from Indigofera spp. This method does not rely on the old fermentation procedure used throughout Northern Europe and is cheap, clean and efficient. Evolved from laboratory-based tests, it involves steeping the leaves at low pH in warm water and extracting the indigo at a higher pH, followed by ultra-filtration of the product, which is then left to …

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Conservation Issues Relating To Maerl Beds As Habitats For Molluscs, Jm Hall-Spencer Jun 1998

Conservation Issues Relating To Maerl Beds As Habitats For Molluscs, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman Jun 1998

Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman

School of Geography, Earth and Environmental Sciences

The present paper attempted to forecast the demand for primary energy broadly categorized into: (a) commercial (coal, petroleum, natural gas, and hydropower), and (b) non-commercial energy (rice hull and straw, jute stick, firewoods, crop wastes, etc.) for the period 1992/93-2019/20 AD to facilitate in the energy sector planning and development. The demand forecast, based on past time series data (1972/73-1991/92), is made by utilizing two methods: (a) "Market Penetration Theory" that uses trend extrapolation and inter-fuel substitution priniciples, and (b) "Trend Extrapolation Model" taking into account the the exogenous variables, e.g., GDP and energy/GDP ratio. Results reveal that the fractional …

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Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen Jan 1998

Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen

School of Engineering, Computing and Mathematics Theses

The overall aim of this research was to design, configure and validate a system which was capable of on-line performance monitoring and fault diagnosis of a diesel engine. This thesis details the development and evaluation of a comprehensive engine test facility and automated engine performance monitoring package. Results of a diesel engine fault study were used to ascertain commonly occurring faults and their realistic severities are discussed. The research shows how computer simulation and rig testing can be applied to validate the effects of faults on engine performance and quantify fault severities. A substantial amount of engine test work has …

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3d Object Recognition Based On Constrained 2d Views, Levente Toth Jan 1998

3d Object Recognition Based On Constrained 2d Views, Levente Toth

School of Engineering, Computing and Mathematics Theses

The aim of the present work was to build a novel 3D object recognition system capable of classifying man-made and natural objects based on single 2D views. The approach to this problem has been one motivated by recent theories on biological vision and multiresolution analysis. The project's objectives were the implementation of a system that is able to deal with simple 3D scenes and constitutes an engineering solution to the problem of 3D object recognition, allowing the proposed recognition system to operate in a practically acceptable time frame. The developed system takes further the work on automatic classification of marine …

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Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat Jan 1998

Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat

School of Geography, Earth and Environmental Sciences Theses

Flow through soil into groundwater has been classically conceptualised as taking place through a set of aligned capillary tubes. In solute transport models these approximations are also present. Pore-Cor (a network model) has been used to model the void structure of soil by using water retention and mercury porosimetry curves. The model successfully predicts trends in saturated hydraulic conductivity. The effect of the assumptions used in the Pore-Cor geometry have been investigated by comparing of two dimensional slices of the simulated networks with two dimensional image analysis data. The geometric limitations of the model cause packing inefficiencies which prevent the …

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Creating Practitioners Of Design For Quality Through Education, Aj Robotham Jan 1998

Creating Practitioners Of Design For Quality Through Education, Aj Robotham

School of Engineering, Computing and Mathematics

The WDK Workshop in Pedagogics in Design Education provides an ideal opportunity to reflect upon my experiences of teaching engineering design at tertiary level and review some of the fundamental elements of design education practice. In particular, I will reflect upon the design experience provided at Coventry University where I taught until quite recently.

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Problem Based Learning And Its Use On The Automotive Engineering Design Course At Coventry University, Aj Robotham Jan 1998

Problem Based Learning And Its Use On The Automotive Engineering Design Course At Coventry University, Aj Robotham

School of Engineering, Computing and Mathematics

The Automotive Engineering Design course at Coventry University has been in operation since October 1989 and has earned a reputation for creating able engineers well prepared for industry. When originally conceived, a problem led approach to learning was adopted across the course. This approach best enables the course objectives to be satisfied. However, there is nothing new about problem-based learning for engineering design educators but for our engineering science colleagues a degree of novelty has been encountered by this approach. But is the success of the course purely down to this teaching and learning approach? This paper will discuss the …

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Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray Jan 1998

Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray

School of Geography, Earth and Environmental Sciences

There is a dearth of information on the employment effects of modern agricultural tech nology on rural women in Bangladesh. The present study1 looks at women's participation in crop production activities, examines their influence in the diffusion of modern technol ogy and their participation in the hired labor market. Data for this study comes from two intensive surveys conducted in the crop years 1989 and 1996 in three agro-ecological regions of Bangladesh. Findings suggest that the prevailing claim-that women are involved only in post- harvest processing of crops-underestimates their contribution to agricultural production. Women's share of total labor is 10-18 …

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Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor Jan 1998

Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor

School of Geography, Earth and Environmental Sciences Theses

A low pressure-inductively coupled plasma (LP-ICP) ion source has been investigated for the production of atomic and molecular ions for mass spectrometry (MS). A dedicated LPICP- MS was constructed, by modifying a Hewlett Packard mass selective detector, to detect ions from the LP-ICP. The ion sampling interface and ion optics were designed using established theory and the use of a computer simulation program. Perfluorotributylamine was continuously introduced into the LP-ICP, via a molecular leak, and the ion sampling interface, plasma forward power, and plasma gas flow rates, were optimised. When the LP-ICP ion source was sustained at 6W with a …

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Behaviour, Welfare And Nutrition Of Group-Housed Sows Fed In An Electronic Sow Feeding System, Nicola Jane Hodgkiss Jan 1998

Behaviour, Welfare And Nutrition Of Group-Housed Sows Fed In An Electronic Sow Feeding System, Nicola Jane Hodgkiss

Other Faculty of Science and Engineering Theses

A programme of study was undertaken to assess the welfare status of multiparous gestating sows housed in dynamic groups in a straw yard and fed by electronic sow feeders (ESF).Comparison of production figures from the Seale-Hayne herd with those nationally confirmed its status as a typical commercial unit. In an initial series of investigations, detailed ethograms were compiled to describe the animals' repertoire of activities and interactions. Lying and straw manipulation were found to be the predominant behaviours and attacks directed towards the head were the most commonly performed type of interaction. Although there was little evidence of aggressive behaviour, …

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The Generation Of Compound Nominals To Represent The Essence Of Text The Commix System, Jennifer Vivien Norris Jan 1998

The Generation Of Compound Nominals To Represent The Essence Of Text The Commix System, Jennifer Vivien Norris

Other Faculty of Science and Engineering Theses

This thesis concerns the COMMIX system, which automatically extracts information on what a text is about, and generates that information in the highly compacted form of compound nominal expressions. The expressions generated are complex and may include novel terms which do not appear themselves in the input text. From the practical point of view, the work is driven by the need for better representations of content: for representations which are shorter and more concise than would appear in an abstract, yet more informative and representative of the actual aboutness than commonly occurs in indexing expressions and key terms. This additional …

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The Later Political Career Of R.A. Butler 1951-1964, Nicholas Adam Patch Jan 1998

The Later Political Career Of R.A. Butler 1951-1964, Nicholas Adam Patch

Other Faculty of Arts, Humanities and Business Theses

R. A. Butler was one of the most influential and yet enigmatic of twentieth century politicians. He did more than anyone to stimulate the revival of post-war Conservatism, which led to three consecutive general election victories. He was a powerful figure in all Conservative Cabinets from 1951 to 1964, serving in each of the three main offices of state, and he nearly became Prime Minister twice. This thesis seeks to challenge the commonly held belief that the post-war Conservative policies developed by Butler represented an acceptance of the mixed-economy welfare-state, as established by the Labour Government between 1945 and 1951. …

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Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon Jan 1998

Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon

School of Geography, Earth and Environmental Sciences Theses

The distribution of trace metals (Fe, Mn, Cu, Cd and Pb) has been determined in dissolved and particulate phases, along with relevant hydrographic parameters, from the nearshore coastal zone of the western North Sea (between 52ON and 56ON) during four Land Ocean Interaction Study (LOIS) surveys covering the seasonal cycle (autumn 1994 to summer 1995) The behaviour of the redox-sensitive metals, Fep and Mnp in the western North Sea were strongly correlated (r>0 44 for all seasons, P<0 05) in all surveys and exhibited maximum concentrations in winter (16 mg g -1 and 700 ug g-1 respectively) which progressively decreased throughout the year Distinct seasonal variations were also observed for particulate Cu, Cd and Pb For example, enhanced concentrations of Cup (36 ± 39 ug g-1) and Cdp (0.36 ± 0.42 ug g -1) in the Humber coastal zone during summer were attributed to preferential particulate organic/biogenic-metal interactions. In contrast enhanced, though diffuse, atmospheric inputs of Pb from continental winds were considered to have contributed to the elevated Pbp concentrations (82 ± 27 ug g -1) observed offshore during winter Results from radiotracer incubation experiments suggest that biological activity makes a significant contribution to the removal of dissolved Mn and Cd to the particulate phase. However, a phase lag of two to three months between maximum primary productivity and maximum particulate metal adsorption (KD=2 X 104 & 5 x 102 for Mn and Cd respectively) indicates a decoupling from the spring plankton bloom In general metal distributions in the Humber coastal zone were significantly influenced by freshwater discharge, tidal regime at the mouth of the estuary and prevailing wind conditions Total trace metal fluxes across the mouth of the Humber Estuary were highest during spring (311, 8 96 & 1045 kg day-1, for Cu, Cd and Pb respectively) and lowest during summer (25 7, 1 .12 & 33 4 kg day-1, for Cu, Cd and Pb respectively) They were dominated by variations in freshwater outflow and the tidal range during sampling On an annual basis comparison to estuarine inputs (rivers, industry and sewage sources) suggested retention of Cu (25%) and Cd (56%) Estimates of partitioning (KD) were derived from the dissolved and particulate data for Cu, Cd and Pb over the seasonal cycle Copper was dominated by the particulate phase (73-80%) in all seasons but summer, whilst Cd showed particulate phase dominance (54-70%) in autumn and winter only The Pb distributions were dominated by the particulate phase (94-99%) independent of season Trace metal settling velocities implied that the Humber Plume was acting as a sink for Cu, Cd and Pb in winter and spring However settling velocities calculated for Cd and Pb (flood tide) in summer were similar to background suspended particulate matter (SPM) suggesting long range transport with the residual circulation. Modelling of Pb isotopic ratios in the Humber Plume suggested that on average 32-39% of the extracted Pbp originated from anthropogenic sources The data from this study has given unique information concerning the concurrent seasonal distributions of particulate trace metals in the western North Sea and have yielded new insights into mechanisms affecting trace metal cycling and transport, essential in the development and refinement of coupled hydrodynamic-geochemical models.

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A Young Lens Of Red Sea Water In The Arabian Sea, S. L. Meschanov, G. I. Shapiro Jan 1998

A Young Lens Of Red Sea Water In The Arabian Sea, S. L. Meschanov, G. I. Shapiro

School of Biological and Marine Sciences

No abstract provided.

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Automated Interpretation Of The Background Eeg Using Fuzzy Logic, Edward Peter Riddington Jan 1998

Automated Interpretation Of The Background Eeg Using Fuzzy Logic, Edward Peter Riddington

School of Engineering, Computing and Mathematics Theses

A new framework is described for managing uncertainty and for deahng with artefact corruption to introduce objectivity in the interpretation of the electroencephalogram (EEG). Conventionally, EEG interpretation is time consuming and subjective, and is known to show significant inter- and intra-personnel variation. A need thus exists to automate the interpretation of the EEG to provide a more consistent and efficient assessment. However, automated analysis of EEGs by computers is complicated by two major factors. The difficulty of adequately capturing in machine form, the skills and subjective expertise of the experienced electroencephalbgrapher, and the lack of a reliable means of dealing …

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