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Imbedded Integration Rules And Their Applications In Bayesian Analysis, Petros Dellaportas Jan 1990

Imbedded Integration Rules And Their Applications In Bayesian Analysis, Petros Dellaportas

School of Engineering, Computing and Mathematics Theses

This thesis deals with the development and application of numerical integration techniques for use in Bayesian Statistics. In particular, it describes how imbedded sequences of positive interpolatory integration rules (PIIR's) obtained from Gauss-Hermite product rules can extend the applicability and efficiency of currently available numerical methods. The numerical strategy suggested by Naylor and Smith (1982) is reviewed, criticised and applied to some examples with real and artificial data. The performance of this strategy is assessed from the viewpoint of 3 criteria: reliability, efficiency and accuracy. The imbedded sequences of PIIR’s are introduced as an alternative and an extension to the …

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Controlled Stress Rheometry, Kevin Golden Jan 1990

Controlled Stress Rheometry, Kevin Golden

School of Engineering, Computing and Mathematics Theses

The work in this thesis is concerned with a theoretical and experimental investigation of certain time dependent simple flow situations on a controlled stress rheometer. We begin by carrying out a viscoelastic analysis of unidirectional combined steady and oscillatory shear flow, that is valid for large oscillatory shear amplitudes. The theory uses a corotational Goddard-Miller model to describe the non-linear relationship between the shear stress and shear rate in the fluid. Our main interest in this work is the description of the reduction in mean shear stress in the fluid due to the fluctuation of the shear rate about a …

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Pneumatic Hydropower Systems, Ian Christopher Parmee Jan 1990

Pneumatic Hydropower Systems, Ian Christopher Parmee

School of Engineering, Computing and Mathematics Theses

The following thesis investigates the performance and economics of a Pneumatic Water Engine capable of extracting energy from differential heads of water in the two to three metre range. Initial concepts are discussed and a system configuration is physically modelled at a laboratory scale. Outline designs using a variety of materials are developed and these provide a basis for the estimation of a probable capital cost using standard Civil Engineering methods. The proposed system is mathematically modelled using a lumped mass approach to the complex hydrodynamics. The resultant differential equations are solved by means of a variable Runge Kutta numerical …

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Real-Time Portable Multi-Layer Perceptron Voice Fundamental-Period Extractor For Hearing Aids And Cochlear Implants, J. R. Walliker, I. Howard Jan 1990

Real-Time Portable Multi-Layer Perceptron Voice Fundamental-Period Extractor For Hearing Aids And Cochlear Implants, J. R. Walliker, I. Howard

School of Engineering, Computing and Mathematics

No abstract provided.

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Federalism And Federation In Europe: A Comparative Study Of The Germanic Tradition, Kurt Richard Luther Aug 1989

Federalism And Federation In Europe: A Comparative Study Of The Germanic Tradition, Kurt Richard Luther

Other Faculty of Arts, Humanities and Business Theses

This thesis defines "federation" as a set of structures and techniques, by means of which the constituent members of a union are given guaranteed access to and are accommodated within the decision-procedure of the centre. Meanwhile, "federalism" is taken to signify the philosophical, or ideological prescription, or promotion, of such a union. The thesis commences by identifying the major shortcomings of the Anglo-Saxon academic literature on federation for a comparative analysis of federalism and federation in Austria, Switzerland and Germany. The two main aims of the thesis are then outlined. These are first, to identify the nature of the tradition …

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The Structure And Function Of Peripheral Blood Leucocytes And Gut-Associated Lymphoid Tissue In The Cichlid, Oreochromis Mossambicus, Teresa Ann Doggett Jan 1989

The Structure And Function Of Peripheral Blood Leucocytes And Gut-Associated Lymphoid Tissue In The Cichlid, Oreochromis Mossambicus, Teresa Ann Doggett

School of Biological and Marine Sciences Theses

The peripheral blood of O.mossambicus was examined using light and electron microscopy and was found to contain four forms of leucocytes: lymphocytes, thrombocytes, monocytes and three types of granulocytes. The monocyte and two types of granulocyte were found to be phagocytic and ingest colloidal carbon and bacteria. The alimentary tract was found to contain a number of leucocytes, some showing a morphological similarity to those in the peripheral blood, while others were unique to the gut tissue. These intestinal leucocytes were found mainly as a diffuse cell population in the epithelium and lamina propria, and only occasionally as discrete lymphoid …

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Ecology Of The Velvet Swimming Crab Liocarcinus Puber (L.) (Brachyura: Portunidae), Christopher Paul Norman Jan 1989

Ecology Of The Velvet Swimming Crab Liocarcinus Puber (L.) (Brachyura: Portunidae), Christopher Paul Norman

School of Biological and Marine Sciences Theses

Currently, Liocarcinus puber is commercially fished in the United Kingdom and exported to Southern Europe. The species appears particularly vulnerable to overfishing and has a history of overexploitation. The present study has examined the reproduction, growth and diet of L. puber, to provide information on which to manage this fishery. Immature Liocarcinus puber were first observed in late summer at a size of 6-10mm long carapace width (LCW). Growth in immature crabs was rapid, and sexual maturity occurred after approx. one year at 45mm (for males) and 40mm (for females) LCW. To differentiate the modal growth of mature crabs, probit …

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Lchthyophthiriasis In Fish: Genetic Variation In Resistance To Infection, Graham Maurice Clayton Jan 1989

Lchthyophthiriasis In Fish: Genetic Variation In Resistance To Infection, Graham Maurice Clayton

School of Biological and Marine Sciences Theses

The frequency and severity of fish diseases is; increasingly, being reported as a limiting factor in the future development of aquaculture. The control of fish disease is largely performed in retrospect through curative chemotherapy. However, the development of resistant strains of fish places the emphasis on preventative, rather than the curative, control of disease. The freshwater parasite Icthyophthirius multifiliis causes the disease known as ichthyophthiriasis or white spot. Losses of fish due to this parasite are believed to total over one million dollars per annum worldwide. The objective of this study was to examine the genetics of resistance to I. …

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Real Time Microprocessor Techniques For A Digital Multitrack Tape Recorder, Terence Donnelly Jan 1989

Real Time Microprocessor Techniques For A Digital Multitrack Tape Recorder, Terence Donnelly

School of Engineering, Computing and Mathematics Theses

Transport properties of a standard compact - cassette tape system are measured and software techniques devised to configure a low - cost,direct digital recording system. Tape - velocity variation is typically ± 10% of standard speed over tape lengths of 5 µm.with occasional variations of ±40%. Static tape - skew can result due to axial movement of the tape reel when it spools.Dynamic tape skew occurs and is primarily caused by tape - edge curvature with a constant contribution due to the transport mechanism.Spectral skew components range from 0.32 Hz to 8 Hz with magnitude normally within one 10 kbit/ …

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The Numerical Solution Of The Dynamic Fluid-Structure Interaction Problem., Paul John Harris Jan 1989

The Numerical Solution Of The Dynamic Fluid-Structure Interaction Problem., Paul John Harris

School of Engineering, Computing and Mathematics Theses

In this thesis we consider the problem of the dynamic fluid-structure interaction between a finite elastic structure and the acoustic field in an unbounded fluid-filled exterior domain. We formulate the exterior acoustic problem as an integral equation over the structure surface. However, the classical boundary integral equation formulations of this problem do not have unique solutions at certain characteristic frequencies (which depend on the surface) and it is necessary to employ modified boundary integral equation formulations which are valid for all frequencies. The modified integral equation formulation used here involves certain arbitrary parameters and we shall study the effect of …

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A Preconcentration Technique For The Determination Of Trace Elements, Andrea Jane Ambrose Jan 1989

A Preconcentration Technique For The Determination Of Trace Elements, Andrea Jane Ambrose

School of Geography, Earth and Environmental Sciences Theses

A novel preconcentration technique for the determination of trace metal impurities in fine chemicals has been developed. The technique involved forming metal chelates in solution with Chrome Azurol S, and adsorbing them onto powdered activated carbon. Afte r separation by filtration, the enriched carbon was made into a slurry and analysed by ICP-AES. Ca, Cu, Fe(III), Mg, Mn and Ni , were all successfully adsorbed onto the carbon from water with recoveries of 100, 96, 100, 98, 97 and 100% respectively. Cu was adsorbed from aqueous solutions of glucose (30%), sucrose (20%) and potassium nitrate (10%), with recoveries of 100, …

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Mid-Victorian Plymouth: A Social Geography, Vivien Frances Turner Pointon Jan 1989

Mid-Victorian Plymouth: A Social Geography, Vivien Frances Turner Pointon

School of Geography, Earth and Environmental Sciences Theses

In the 19th century, the two settlements of Plymouth and East Stonehouse grew and coalesced into one urban area. Natural population increase and immigration both contributed to the rapid population growth which gave impetus to the urban expansion. Analysis of the unpublished census manuscripts for I85I and I87I revealed clear patterns of distrihution indicating segregation according to demographic, occupational and birthplace characteristics. There was severe overcrowding, population density was higher than that of mid-Victorian London and Liverpool, and the consequences for local public health and on the morphology of the urban area were substantial. Deprivation and poverty occurred not only …

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Characterisation Of Unresolved Complex Mixtures Of Hydrocarbons, Mark Adrian Gough Jan 1989

Characterisation Of Unresolved Complex Mixtures Of Hydrocarbons, Mark Adrian Gough

School of Geography, Earth and Environmental Sciences Theses

The hydrocarbons of Recent Polluted.., sediments, in-reservoir and laboratory biodegraded crude oils, and certain petroleum products (e. g. lubricating oils) often display "humps" or Unresolved Complex Hixtures (UCHs) when analysed by gas chromatography (CC). Although widespread and often abundant, to date little is known of their detailed molecular composition. Standard chromatographic methods of isolation of model aliphatic and aromatic hydrocarbon UCMs from lubricating oils followed by conventional methods of analysis provided little compositional detail. Thus CC and CC-electron impact mass spectrometry (GC-EIMS) was limited to an estimate of carbon number ranges and to the identification of certain series of *biological …

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Plasma Spectrochemical Analysis Of Slurries, Michael Edward Foulkes Jan 1989

Plasma Spectrochemical Analysis Of Slurries, Michael Edward Foulkes

School of Geography, Earth and Environmental Sciences Theses

The analysis of ores, minerals and refractory materials by slurry atomisation has been investigated using inductively coupled plasma and direct current plasma-atomic emission spectrometry (ICP-AES, DCP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS). Aqueous calibrants were used. Fundamental aspects were modelled. The particle size and dispersion of samples are the most important criteria in slurry nebulisation. The particle size should be below 5 µm, preferably below 3 µm for refractories. Comminution techniques were used to reduce samples to this size range; the comminution time depended upon sample hardness. Suitable dispersants were identified. Laser diffraction measurements showed the modification of aerosol distributions, …

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Analysis Of Organic Samples By Plasma Spectrometry, Evan Hywel Evans Jan 1989

Analysis Of Organic Samples By Plasma Spectrometry, Evan Hywel Evans

School of Geography, Earth and Environmental Sciences Theses

The application of inductively coupled plasma (ICP) spectrometry to the analysis of organic compounds is reviewed. Problems associated with such analyses are identified and methods to overcome them are described.

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Soil Loosening And Drainage Efficiency Of Silt Soils, Stephen John Twomlow Jan 1989

Soil Loosening And Drainage Efficiency Of Silt Soils, Stephen John Twomlow

Other Faculty of Science and Engineering Theses

An experiment was set up to investigate the effects of soil loosening on the drainage efficiency of a structurally unstable silty clay loam in Devon. Such soils are common to the Palaeozoic slates of South West England, and in many parts of Wales and Scotland. The dominance of the fine earth fraction these soils by silt sized particles and the associated low clay fractions ( 10-35%) gives rise to weak structures that are unsuitable f or mole drainage. Six drains were laid with permeable fill at a 20 m spacing on a gently sloping site at Seale-Hayne College Farm. A …

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Water Use By Pigs Managed Under Various Conditions Of Housing, Feeding, And Nutrition, Bhupinder Pal Gill Jan 1989

Water Use By Pigs Managed Under Various Conditions Of Housing, Feeding, And Nutrition, Bhupinder Pal Gill

Other Faculty of Science and Engineering Theses

This study investigated the water use of lactating sows (experiment 1), suckling piglets (experiment 2), weaned piglets (experiments 3, 6 and 8) and growing pigs (experiments 4, 5, 7 and 9), according to 3 specific objectives which assessed the effects of: age, live weight, feed intake and physiological status on water demand (experiments 1 to 3); different types of drinker on water use (experiments 4 to 6); dietary mineral content on water demand (experiments 7 and 8). For all classes of pig, feed intake explained between 53 and 83% of the variation in water use (P < 0.001). The relationship between stage of lactation and live weight (experiments 3, 6 and 7) was confounded by feed intake. In sows water use increased linearly in the week before farrowing (P < 0.001) which then decreased from 12.3 ± 1.10 1 the day before, to 9.3 ± 0.84 1 the day of farrowing (P < 0.001). Water use averaged 18.9 ± 0.27 1/day in a 21 day lactation. With suckling piglets, provision of water and/or creep feed between days 8 and 21 did not influence growth ( P > 0.05). Provision of creep …

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The Impact Of Deregulation On The Perceptions Of Urban Public Transport Users, Alison Jane Green Jan 1989

The Impact Of Deregulation On The Perceptions Of Urban Public Transport Users, Alison Jane Green

Other Faculty of Science and Engineering Theses

The deregulation of stage carriage bus services represented a major change in the structure and operation of the bus industry in the U.K. Therefore, there existed a need to monitor the effects of the changes brought about by deregulation on the travelling public. Although, many research projects were set up to monitor deregulation, the paucity of attitudinal research meant that this project fills an important gap in the monitoring process. Plymouth was chosen because it had a fairly typical municipal bus operator, and one other major operator. In addition, no other research establishment was doing any detailed research in the …

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Electricity Use In The Farm Dairy, Robert Christopher Bowes Jan 1989

Electricity Use In The Farm Dairy, Robert Christopher Bowes

Other Faculty of Science and Engineering Theses

Dairy farmers suffered substantially increased energy bills during the 1970's, at a time of herd expansion and modernisation of equipment to allow bulk milk refrigeration and storage on the farm. Little was known of the levels of electricity use in the dairy farming sector, but extrapolations had suggested a figure of 300 to over 400 kWh/cow/annum. Farmers were requesting quantitative estimates for the potential of conservation equipment, particularly plate heat exchangers and heat recovery units. An energy audit of dairy farms in South Devon is described. Over a period of two years, data were collected relating to energy use by …

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The European Perception Of The Native American, 1750 - 1850, Stephanie Rose Pratt Jan 1989

The European Perception Of The Native American, 1750 - 1850, Stephanie Rose Pratt

Other Faculty of Arts, Humanities and Business Theses

The thesis on which I have based my research proposes that while the European perception of the Native American from 1750 to 1850 came to be mediated via all the visual arts, it was specifically via the graphic media that the proliferation of imagery concerning the Native American developed certain iconic and representational conventions and that these consistently overwhelmed other sources of information, from experience to written interpretation. The ubiquity of certain modes of presentation, of figure-types, and of synecdoches which stood for the Native American (e.g. feather decoration or the tomahawk) resulted almost entirely from graphic methods of visual …

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British Seamen's Missions And Sailors Homes 1815 To 1970 Voluntary Welfare Provision For Serving Seafarers, Alston Kennerley Jan 1989

British Seamen's Missions And Sailors Homes 1815 To 1970 Voluntary Welfare Provision For Serving Seafarers, Alston Kennerley

Other Faculty of Arts, Humanities and Business Theses

From the 1820s an ever present feature of most British ports has been the voluntary societies, little studied before, offering spiritual and social welfare support to serving seafarers. The perspective taken in this study is that although there were numerous individual societies, voluntary effort for seafarers constitutes a single movement. The continued existence of many societies well into the twentieth century suggests that the movement should be examined longitudinally in order to assess its contribution in relation to the changing context in which such welfare operated.

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The Application Of Modern Portfolio Theory To Hedging In The Dry Bulk Shipping Markets, Kevin Patrick Brendan Cullinane Jan 1989

The Application Of Modern Portfolio Theory To Hedging In The Dry Bulk Shipping Markets, Kevin Patrick Brendan Cullinane

Other Faculty of Science and Engineering Theses

Risk and uncertainty have a vital impact on any business, but are particularly influential in the shipping industry. Although risk and uncertainty constitute the life-blood that courses through the veins of business, decision makers typically attempt to reduce the risks to which their decisions are subject. This is because there inevitably exists a level of risk which the decision maker is unwilling to accept. In May 1985 a new method of risk reduction in shipping became available through the introduction of BIFFEX — the Baltic International Freight Futures Exchange. Participants in shipping can now hedge against their risks in the …

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Modern Cornwall: The Changing Nature Of Peripherality, Philip John Payton Jan 1989

Modern Cornwall: The Changing Nature Of Peripherality, Philip John Payton

Other Faculty of Arts, Humanities and Business Theses

The political events of the 1960s and 1970s in "Celtic Britain" led to the demise of the Anglocentric conventional wisdom which had asserted the fundamental homogeneity of the United Kingdom, and ushered in a new orthodoxy which stressed diversity and the territorial dimension of the state. Ihese events were mirrored to an extent in Cornwall, with competing explanations seeking to interpret "peripheral protest", but with a more comprehensive model emerging to emphasise the complexity of the relationship between "centre" and "periphery" in modern western European states, pointing in particular to the existence of historical phases of peripherality. In an initial …

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Analysis Of Iterative Methods For The Solution Of Boundary Integral Equations With Applications To The Helmholtz Problem, Chen Ke Jan 1989

Analysis Of Iterative Methods For The Solution Of Boundary Integral Equations With Applications To The Helmholtz Problem, Chen Ke

School of Engineering, Computing and Mathematics Theses

This thesis is concerned with the numerical solution of boundary integral equations and the numerical analysis of iterative methods. In the first part, we assume the boundary to be smooth in order to work with compact operators; while in the second part we investigate the problem arising from allowing piecewise smooth boundaries. Although in principle most results of the thesis apply to general problems of reformulating boundary value problems as boundary integral equations and their subsequent numerical solutions, we consider the Helmholtz equation arising from acoustic problems as the main model problem. In Chapter 1, we present the background material …

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Learning And Instructional Success In People With A Mental Handicap, Stephen Charles Strand Jan 1989

Learning And Instructional Success In People With A Mental Handicap, Stephen Charles Strand

School of Psychology Theses

Learning - the process by which new skills and behaviours are acquired - is a central concept in the understanding of mental handicap. Discrimination learning Is specifically identified as an essential pre-requlslte for the acquisition of a variety of more complex behaviours and skills. Many studies have reported that severely mentally handicapped persons show a relative inability to profit from unstructured learning experiences, and frequently fail to learn discriminations trained through simple differential reinforcement (trial-and-error training). Programmed training procedures are identified as important vehicles to facilitate the discrimination learning of severely mentally handicapped children. An initial study is reported that …

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The Nitriding Of High Speed Steel Cutting Tools, Glen Alexander Crust Jan 1989

The Nitriding Of High Speed Steel Cutting Tools, Glen Alexander Crust

School of Engineering, Computing and Mathematics Theses

There is an interest in industry in cost reduction. Tool wear constitutes an important element in the cost of many metalworking processes, not only because of the cost of the tool, but also because of the cost of machine downtime. Saltbath nitriding of high speed steel tools adds only about 1%to the cost of a finished tool, but has been found to confer benefits considerably in excess of this over a range of cutting conditions .A series of cutting tests is described, during which cutting forces and tool temperatures were recorded simultaneously using microcomputer based instrumentation developed at the Polytechnic …

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The Interaction Between Unburnt Hydrocarbons And Soot In Diesel Exhausts, Christopher Richard Seebold Jan 1989

The Interaction Between Unburnt Hydrocarbons And Soot In Diesel Exhausts, Christopher Richard Seebold

School of Engineering, Computing and Mathematics Theses

The potential health risk of diesel particulate (DP) has stimulated research into its physical and chemical composition. Its interaction with unburnt hydrocarbons (UHC) at exhaust temperatures was studied (i.e. composition and microstructure), at varying engine conditions. A hot whole exhaust filtration system was developed to collect DP on Pallflex TX-40 PTFE coated filters (for minimal artefact formation) down the exhaust of a Ricardo E6/T IDI diesel engine. Electron microscopy (SEM and TEM) and a gravimetric BET method determined particle size, specific surface area (SSA) and pore character. An in vacuo gravimetric thermal degassing (TD) apparatus was constructed to extract adsorbed …

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Compressive Membrane Action In Bridge Deck Slabs, Paul Austin Jackson Jan 1989

Compressive Membrane Action In Bridge Deck Slabs, Paul Austin Jackson

School of Engineering, Computing and Mathematics Theses

An elastic analysis of restrained slab strips shows that membrane action enhances serviceability behaviour. However, the enhancement is not as great as for strength and serviceability is critical when membrane action is considered in design. A relatively simple form of non-linear finite element analysis is developed which is able to model bridge deck behaviour allowing for membrane action. This reduces some of the disadvantages of non-linear analysis which have prevented its use in practice. It uses line elements but, because of novel features of the elements and because it considers all six degrees of freedom at each node, it is …

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Developmental Changes In The Distribution And Diet Of Nucella Lapillus (L.) From A Mussel Dominated Shore, Jean Harris Jan 1988

Developmental Changes In The Distribution And Diet Of Nucella Lapillus (L.) From A Mussel Dominated Shore, Jean Harris

School of Biological and Marine Sciences Theses

Aspects of the developmental biology of an intertidal predatory gastropod, Nucella lapillus were investigated for a population located on a mussel dominated shore at Whitsand Bay, Cornwall. A field sampling programme revealed that the centre of abundance of small Nucella {<3.4mm) occurred at lower shore levels than that of a larger individuals and the egg capsules. Laboratory studies demonstrated that hatchlings are both negatively geotactic and phototactic, directing than upshore and into crevices.The relative profitabilities of four different sized mussels to four developmental stages of Nucella were investigated using both ability to promote growth and energy gain per unit handling time (E/T) as measures of prey value. The response curves were similar in that proportionately large and small prey were less profitable than medium sized prey with the optimal prey size increasing with predator size. However the most profitable size according to the E/T model was larger than in the growth rate model because large meals appeared to be less efficiently utilized.An ontogenetic- shift in prey size selection was demonstrated in laboratory and field, the results of which were more accurately predicted by the growth rate model of prey value. Predatory events in the field were investigated using borehole dimension as an index of predator size. The feeding and growth of Nucella were investigated at differing periods of tidal emersion. Growth rates were substantially reduced at emersion periods of above 30%, but these could not be wholly attributable to reduced feeding rates. Field growth trials demonstrated that a mature size could be reached in 19-21 months, that growth does not cease at maturity, and that juveniles grow throughout the year. A strong correlation existed between growth rate and environmental temperature. Growth rates in the field were about 75% those in the laboratory, suggesting few constraints on foraging in the field.

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Osmoregulation In The Prawn Palaemon Longirostris (Caridea, Palaemonidae), Peter J Campbell Jan 1988

Osmoregulation In The Prawn Palaemon Longirostris (Caridea, Palaemonidae), Peter J Campbell

School of Biological and Marine Sciences Theses

Salinity tolerance, and several aspects of osmoregulation, ionic regulation and permeability were measured for Palaemon longirostris at three temperatures (4, 12 & 20°C). Influence of ontogenetic stage on salinity tolerance and osmoregulation was investigated by testing separately individuals sorted, using carapace length, into 'small' (10-18mm), 'medium' (18-24mm), 'large' (>24mm) and 'ovigerous' (>24mm) size groupings. Effect of seasonal acclimatization on salinity tolerance and osmoregulation was taken into account by comparing responses of summer- with winter-collected prawns. Irrespective of temperature and size, summer Palaemon longirostris were extremely euryhaline and had >90% survival in various salinities from 0.5-34 º/oo . For …

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