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The Design And Implementation Of Manufacturing Infrastructures, Stephen Childe Jan 1991

The Design And Implementation Of Manufacturing Infrastructures, Stephen Childe

School of Engineering, Computing and Mathematics Theses

This work addresses the problem of difficulties in the implementation of Computer Aided Production Management systems, and presents a methodology for their implementation which significantly improves on current practice. The methodology provides a structured approach which leads the company through a series of strategic business decisions which establish the context within which the solution must operate. The work focusses attention upon the design of the whole system with respect to the relationship between computerised functions and the infrastructure of human elements which facilitate and govern the system's operation. A model of the tasks involved in production management is presented. The …

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Development Of A Computing And Information Systems Infrastructure For Capm In A Computer Integrated Manufacturing Environment, Neil Weston Jan 1991

Development Of A Computing And Information Systems Infrastructure For Capm In A Computer Integrated Manufacturing Environment, Neil Weston

School of Engineering, Computing and Mathematics Theses

The continuing failure of many CAPM implementations in the UK, despite the availability of a large and growing supply of software, gave rise to concern within the academic and user community and highlighted a need for a concerted research effort into the causes of failure. The Science and Engineering Research Council responded to this need by sponsoring a major research initiative into CAPM through its ACME (Application of Computers to Manufacturing Engineering) Directorate. The findings reported in this thesis result from the work carried out for ACME by the author as part of the joint Polytechnic South West/Sheffield Business School …

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Linguistic And Semantic Factors In Conditional Reasoning, Matthew Charles Ellis Jan 1991

Linguistic And Semantic Factors In Conditional Reasoning, Matthew Charles Ellis

School of Psychology Theses

Two complementary sets of experiments were carried out to investigate how people understand, and reason with, truth-functional conditional forms. The first four experiments employed abstract materials and sought primarily to investigate the notion that people interpret conditionals like ‘if P then Q’ a ‘fuzzy’ way – that is, as if such a statement means something like ‘if P then, generally speaking, Q’. Evidence was found that people will tolerate, or even expect, a certain degree of fuzziness in a conditional scenario such that they will be prepared to rate such a conditional statement as true despite the existence of a …

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Prediction Of The Flow And Heat Transfer Between A Rotating And A Stationary Cone, Nicholas Edward May Jul 1990

Prediction Of The Flow And Heat Transfer Between A Rotating And A Stationary Cone, Nicholas Edward May

School of Engineering, Computing and Mathematics Theses

This thesis is concerned with the development of a theoretical method for predicting the turbulent flow and heat transfer in the cavity between a rotating and a stationary cone. The motivation for the work stems from the need, in the design process for the gas turbine aero-engine, for a fast and reliable predictive method for such flows. The method developed here is the integral method, which reduces the governing partial differential equations to ordinary differential equations. A number of solution methods for these equations are described, and the optimum in terms of speed and accuracy is indicated. Predicted moment coefficients …

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Chemical Dynamics In North Sea Estuaries And Plumes, Andrew Turner Jan 1990

Chemical Dynamics In North Sea Estuaries And Plumes, Andrew Turner

School of Biological and Marine Sciences Theses

Observational and experimental studies have been undertaken in the southern North Sea environment, including five major estuaries (Humber, Thames, Scheldt, Weser and Elbe), with the aim of elucidating the mechanistic and kinetic details of trace metal reactivity required for the refinement of pollutant transport models. The results of a systematic investigation of suspended particle characteristics (BET specific surface area and porosity, carbon content. Fe and Mn oxide coatings) indicated that, although there exists significant yet explicable variability among the North Sea estuaries, such compositional factors do not exert an observable influence on solid-solution interactions. Furthermore, chemical reactivity was not usually …

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The Immune Responses Of Carp, Cyprinus Carpio L., Following Direct Immersion Immunization, Alan Foster Bridges Jan 1990

The Immune Responses Of Carp, Cyprinus Carpio L., Following Direct Immersion Immunization, Alan Foster Bridges

School of Biological and Marine Sciences Theses

The investigations presented in this thesis include studies on a) the immune responses of carp following direct immersion immunization and subsequent intraperitoneal (i.p.) challenge, b) the uptake and accumulation in carp of a direct immersion vaccine and c) phagocytic uptake by carp peritoneal exudate cells (PECs). To assess the cell-mediated immune response of carp, a micro chemotaxis technique was developed, measuring the production of chemotactic factor-like activity in supernatants from incubations of pronephric cells with antigen. In no case were serum antibody titres or a cell-mediated immune response detectable after immersions alone in antigen. It was found that an i.p. …

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The Immune Response Of The Grey Mullet, Chelon Labrosus (Risso, 1826), To Cryptocotyle Lingua (Creplin, 1825), (Digenea), Bradbury Patrick Wood Jan 1990

The Immune Response Of The Grey Mullet, Chelon Labrosus (Risso, 1826), To Cryptocotyle Lingua (Creplin, 1825), (Digenea), Bradbury Patrick Wood

School of Biological and Marine Sciences Theses

The ability of thick-lipped grey mullet to mount both humoral and cellular immune responses to Cryptocotyle lingua has been demonstrated here for the first time. Of the 3 procedures for immunisation investigated, namely exposure to live cercariae, intraperitoneal (ip) injection of whole killed cercariae and ip injection of a cercarial sonicate, the former gave the highest primary antibody titres with a peak response at 4 weeks post infection. Peak titres occurred at 5 and 7 weeks after immunisation by ip injection of sonicated cercariae and whole killed cercariae respectively. An enhanced secondary antibody response was observed following challenge by ip …

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In Vitro Selection And Characterization Of Lead Resistant Somaclonal Variants From Daucus Carota L., Janice Mary Bateson Jan 1990

In Vitro Selection And Characterization Of Lead Resistant Somaclonal Variants From Daucus Carota L., Janice Mary Bateson

School of Biological and Marine Sciences Theses

Lead was shown to inhibit both callus initiation and callus growth in cultures of Daucus carota L. subsp. sativus (Hoff. Thell.) cv. Nantes ''Tiptop'' and ''Nanthya''. Taproot explants of Daucus carota were stressed with lead. The callus cell lines which initiated under this stress were shown to exhibit resistance to the effects of lead ions. The growth of the selected and nonselected cell lines on non-lead containing media was comparable and the resistance possessed by the selected cell lines did not result in reduced growth rates in the presence of lead. The resistance characteristic was shown to be stable and …

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Factors Affecting The Pathogenicity Of Yersinia Ruckeri, Maria Dolores Furones Nozal Jan 1990

Factors Affecting The Pathogenicity Of Yersinia Ruckeri, Maria Dolores Furones Nozal

School of Biological and Marine Sciences Theses

A group of 42 strains of Yersinia ruckeri were characterized and found to show homogenous biochemical profiles. The optimal conditions for in vitro culture of a representative strain of Y. ruckeri were established. The virulence was increased by passage through fish. A standard method for infection of rainbow trout (Oncorhynchus mykiss) with Y. ruckeri was devised. As a result cultures of Y. ruckeri grown on full strength of BHIA for 5 h at 30°C in static conditions were found to be most suitable for infection by both intraperitoneal injection and immersion. Virulence of stored cultures was maintained for over 1 …

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Immune Response Of Carp Cyprinus Carpio (L.) To IChthyophthirius Multifiliis (Foquet), With Reference To Events Within The Epidermis, Martin Leslie Cross Jan 1990

Immune Response Of Carp Cyprinus Carpio (L.) To IChthyophthirius Multifiliis (Foquet), With Reference To Events Within The Epidermis, Martin Leslie Cross

School of Biological and Marine Sciences Theses

The in vitro and in situ immune responses of carp Cyprinus carpio to Ichthyophthirius multifiliis were investigated in order to characterise the immune mechanisms involved in protection. 'O' group and adult carp were immunised against I.multifiliis by controlled infection procedures. Sterile immunity was not achieved; theronts were observed to penetrate the skin of immunised fish, although in the majority of cases this did not lead to successful trophozoite establishment. It was concluded that most parasites prematurely exited the epidermis of immunised fish within two hours of penetration as an active survival strategy. Trophozoites remaining in immunised fish beyond two hours …

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Erosion And Electrode Energy Distribution In Switches With Silver-Cadmium-Oxide Contacts, Hassan Nouri Jan 1990

Erosion And Electrode Energy Distribution In Switches With Silver-Cadmium-Oxide Contacts, Hassan Nouri

School of Engineering, Computing and Mathematics Theses

The cathode and the anode fall of the DC arcs are measured by fast oscilloscope for Ag-CdO contacts over a range of gap-lengths from 0.05 mm to 1 mm, and currents of 4-10 Amps at atmospheric pressure, with a known electrode closing speed, using the Moving Electrode Method. It was observed that the anode fall can occur in a few places within the arc voltage waveform, and is dependent of the electrodes' surface condition. Both cathode and anode falls increase with gap-length and decrease with current. It was found that when arc length is shorter than electrode separation, discontinuity within …

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The Sedimentology, Palaeoecology And Stratigraphy Of Cretaceous Rocks In N.W. Scotland, Sharon Mary Braley Jan 1990

The Sedimentology, Palaeoecology And Stratigraphy Of Cretaceous Rocks In N.W. Scotland, Sharon Mary Braley

School of Geography, Earth and Environmental Sciences Theses

Sediments of Cretaceous age in N.W. Scotland outcrop in small, often isolated exposures throughout the Inner Hebrides and Morvern, and have been dealt with cursorily in most previous work on the Cretaceous rocks of Britain. The aims of this study were (i)to propose a formal integrated stratigraphic scheme for the Cretaceous strata of N.W. Scotland and (ii)to model the development of the Inner Hebrides Basin (where these strata outcrop) during the Cretaceous Period. Detailed field observations, macro- and micropalaeontology (including palynology), sedimentology and structural data were integrated in an attempt to achieve these aims. Fieldwork was conducted in Morvern (Argy …

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Determination Of Trace Metals By Lon-Chromatography With Chemiluminescence Detection, Timothy Paul Williams Jan 1990

Determination Of Trace Metals By Lon-Chromatography With Chemiluminescence Detection, Timothy Paul Williams

School of Geography, Earth and Environmental Sciences Theses

It is generally considered that the detection step for the determination of trace metals by liquid-chromatographic systems is the weakest area of the analytical procedure. Various post-column reagent systems, for trace metal analysis, based on the highly sensitive luminol-peroxide chemiluminescence (CL) reaction have been developed and are described. A simple cation-exchange chromatographic system was developed and used to separate cobalt from other metal ions. These cobalt ions were detected using an optimised luminol-peroxide CL post-column reagent. A detection limit of 0.5 ng 1̵¹ was achieved without the need for preconcentration, for a 200 µl sample. The cobalt content of a …

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The Characterization And Modelling/Of Soil Water Pathways Beneath A Coniferous Hillslope In Mid Wales, Nicholas Arthur Chappell Jan 1990

The Characterization And Modelling/Of Soil Water Pathways Beneath A Coniferous Hillslope In Mid Wales, Nicholas Arthur Chappell

School of Geography, Earth and Environmental Sciences Theses

Streams draining coniferous plantations contain higher loadings of hydrogen ion, aluminium, sulphate and nitrate, in comparison with streams in adjacent grasslands. Almost all of this ion-load is transported to streams via subsurface water-pathways. An incontrovertible, physical characterization of these pathways within a natural, layered hillslope, has yet to be presented. This research has sought to provide such a characterization for two hillslopes - one afforested with conifers, the other an improved grassland. Much of the uncertainty associated with the identification of soil-water-pathways stems from an inadequate characterization of the errors imposed by the use of each measurement technique. This research …

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Slurry Atomisation System For Process Control, Benedict Evelyn Fairman Jan 1990

Slurry Atomisation System For Process Control, Benedict Evelyn Fairman

School of Geography, Earth and Environmental Sciences Theses

The mechanistic processes of slurry atomisation - Direct Current Plasma - Atomic Emission Spectroscopy (DCP-AES) were investigated using excitation temperature (Texc) measurements , simplex optimisation, particle transport experiments and computerised tomography .

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Arsenic Speciation In Food, Simon Branch Jan 1990

Arsenic Speciation In Food, Simon Branch

School of Geography, Earth and Environmental Sciences Theses

A high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method has been developed for the separation and quantification of ~g kg-1 levels of arsenobetaine, monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA) , arsenite and arsenate. Using this coupling, arsenic species in fruit and vegetables grown on soils containing up to 1.4% w\w arsenic have been surveyed and DMAA, MMAA, arsenite and arsenate identified in the plants. Although extraction efficiencies were poor, typically 10%, total arsenic determinations demonstrated that arsenic uptake by the plants was low, with the highest arsenic level being 60-70 mg kg-1 dry weight in unpeeled potato. Provided the …

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A Continuum Mixture Theory Approach To Sediment Transport With Application To Turbulent Oscillatory Boundary Layers, John Nigel Aldridge Jan 1990

A Continuum Mixture Theory Approach To Sediment Transport With Application To Turbulent Oscillatory Boundary Layers, John Nigel Aldridge

School of Geography, Earth and Environmental Sciences Theses

Two aspects of the modelling of suspended sediment transport are investigated. One is the development of a theoretical base for sediment transport models starting from the continuum theory of immiscible mixtures (also know as two-phase flow theories). The other is a comparison with experimental data of numerical predictions from a number of turbulence models for oscillatory, turbulent boundary layer flow containing suspended sediment. A review is given of previous work that has applied continuum mixture theories to the field of sediment transport. Turbulent averaged forms of the mixture equations are presented and, in the dilute particle concentration limit and neglecting …

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Aspects Of The Micropalaeontology And Stratigraphy Of Cretaceous Shelf Carbonates From The Oman Mountains, Michael Derek Simmons Jan 1990

Aspects Of The Micropalaeontology And Stratigraphy Of Cretaceous Shelf Carbonates From The Oman Mountains, Michael Derek Simmons

School of Geography, Earth and Environmental Sciences Theses

Five outcrop sections (Wadi Mi'aidin, Wadi Bani Kharus, Jebel Madar, Jebel Madamar and Jebel Salak), exposing Thamama and Wasia Group sediments were sedimentologically logged and sampled. Thin sections of each of the Thamama Group samples were prepared for micropalaeontological and microfacies analysis. The foraminifera, calcareous algae and calpionellids in each sample were recorded in order to provide a means of biostratigraphic subdivision, and together with microfacies analysis and sedimentological observations made in the field, provide a means of elucidating the depositional environments of the Thamama Group in the study area. Correlation between outcrop sections has been attempted using a biozonation …

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Studies Of Tin Oxide Gas Sensors For Gas Chromatographic Detection, Peter William Ash Jan 1990

Studies Of Tin Oxide Gas Sensors For Gas Chromatographic Detection, Peter William Ash

School of Geography, Earth and Environmental Sciences Theses

Gas sensitive semiconductors have been known for many years and applied in static gas alarm systems for the monitoring of hazardous gases, however, their application has been limited by a lack of selectivity. In this work a semiconducting gas sensor has been configured for use as a gas chromatographic detector thus combining the sensitivity of semiconductor sensors with the selectivity of gas chromatography. The study has been confined to tin oxide devices, more specifically the Taguchi gas sensor (TGS) . The majority of this work has concentrated on the TGS 813 although the use of other TGS is described. The …

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Geochemistry Of Suspended Particles In The Tamar Estuary, John Smith Findlay Jan 1990

Geochemistry Of Suspended Particles In The Tamar Estuary, John Smith Findlay

School of Geography, Earth and Environmental Sciences Theses

ICP analyses of total rare earth element (REE) abundances in intertidal sediments and suspended particles from the Tamar Estuary show little variation in REE concentrations along the estuary and only minor fractionation relative to standard shale. Fe, Mn, Cu, Zn, Ni & Co abundances in the estuarine suspended particles show significant variations in the turbid upper estuary. Acid leachable REE display different shale normalised patterns with slight enrichment of the mid to heavy REE. Sediment porewater analyses confirm the diagenetic mobility of the REE and show significant heavy REE enrichment consistent with their derivation from a non-detrital source. Detailed studies …

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Cognitive Processes In Engineering Design, Linden John Ball Jan 1990

Cognitive Processes In Engineering Design, Linden John Ball

School of Psychology Theses

The central aim of the current research programme was to gain an understanding of the cognitive processes involved in engineering design. Since little previous empirical research has investigated this domain, two major exploratory studies were undertaken here. Study One monitored seven final-year students tackling extended design projects. Diary and interview data were used to construct detailed design behaviour graphs that decomposed activities into structured representations reflecting the goals and subgoals that were pursued. Study Two involved individual observation (using video) of six professional engineers "thinking-aloud" as they tackled a small-scale design problem in a laboratory setting. A taxonomic scheme was …

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Enzyme Linked Immunological Studies Of Cholinesterases In Human Blood, Jeffrey Wynn Jones Jan 1990

Enzyme Linked Immunological Studies Of Cholinesterases In Human Blood, Jeffrey Wynn Jones

Other Faculty of Health Theses

A modified Ellman method using acetylthiocholine as substrata has been used to reliably measure erythrocyte AChE activity (CV=7%). Reliable immunological quantitation of this enzyme (CV=7%) was achieved using monoclonal antisera to AChE (AE-1 and AE-2) in a fluid phase homogeneous enzyme-linked antiglobulin test (ELAT). AChE activity and antigen levels were similar for both adult male and female samples. Cord samples at term measured 60% of the adult value and reached 100% within 5 months. An overall increase in AChE activity was observed as pregnancy progresses with patients 1 to 3 days post delivery showing significantly elevated levels of activity and …

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Pedestrianisation In Plymouth: The Effect On Car Users' Accessibility To And Within The Traffic Free Zone, Julia Meaton Jan 1990

Pedestrianisation In Plymouth: The Effect On Car Users' Accessibility To And Within The Traffic Free Zone, Julia Meaton

Other Faculty of Science and Engineering Theses

When pedestrianisation was introduced in Plymouth, in February 1987,, there were two important physical changes to the city centre; environment changes and accessibility changes. Environmentally, the city centre was improved aesthetically and also in terms of safety for pedestrians,, less congestion, and ease of movement within the traffic free zone. The process of pedestrianisation initially reduced the accessibility of the city centre, particularly for car users, because the scheme removed nearly all the on-street parking meters together with two small short stay car parks. This caused a temporary reduction in car parking facilities, and the replacement facilities, completed in late …

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A Navigation And Automatic Collision Avoidance System For Marine Vehicles, Keith Mcgowan Miller Jan 1990

A Navigation And Automatic Collision Avoidance System For Marine Vehicles, Keith Mcgowan Miller

Other Faculty of Science and Engineering Theses

Collisions and groundings at sea still occur, and can result in financial loss, loss of life, and damage to the environment. Due to the size and capacity of moden vessels, damage can be extensive. Statistics indicate that the primary cause of accidents at sea is human error, which is often attributed to misinterpretation of the information presented to the mariner. Until recently, data collected from sensors about the vessel were displayed on the bridge individually, leaving the mariner to assimilate the material, make decisions and alter the vessels controls as appropriate. With the advent of the microprocessor a small amount …

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Ideologies In Practice : The Context Of The Youth Training Scheme, Ken Parsons Jan 1990

Ideologies In Practice : The Context Of The Youth Training Scheme, Ken Parsons

Other Faculty of Arts, Humanities and Business Theses

The central concern in the thesis is the relationship between the 'concept of ideology' and the philosophies, motivations and lived experience of Youth Training Scheme (YTS) trainees and trainers. This incorporates both the application, effects and impact of official ideologies, expressed in youth policy initiatives and ideologies of the wider society. This in turn is related to the cultural and societal reproduction of young people as gendered and class specific workers in a segmented labour market. The empirical data were collected over a 20 month period at two off-the-job training establishments in the city of Surfton in the South West …

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'Household Class. The State And Public Attitudes To Welfare', Mark Hyde Jan 1990

'Household Class. The State And Public Attitudes To Welfare', Mark Hyde

Other Faculty of Arts, Humanities and Business Theses

Two specific shifts have occurred in the sectoral bases of welfare provision in the UK since the last war. The first involved in establishment of collective state provision whilst the second has involved a significant expansion of owner occupation. These developments have been interpreted at various times as signifying substantial changes in the nature of British society, particularly in the way that they are alleged to have attenuated class based social divisions and patterns of consciousness. In contemporary debates, owner occupation is alleged to have generated a conservative domestic oriented attitudinal disposition among manual households. Further, such households are held …

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Geographical Perspectives On Residential Provision For The Elderly: With Special Reference To The Voluntary Sector, Margaret Bochel Jan 1990

Geographical Perspectives On Residential Provision For The Elderly: With Special Reference To The Voluntary Sector, Margaret Bochel

Other Faculty of Arts, Humanities and Business Theses

At a time of increasing concern as to how best to care for the growing elderly population in Britain, this thesis examines the spatial distribution of residential care and sheltered housing for this group of the population. With the present government policies of reducing public expenditure and reliance on State welfare services, the main focus of the thesis is on the changing role of the voluntary sector and in particular on its geographical distribution. Little is known about the size and scope of the voluntary sector in Britain, still less about the operation of such organisations in service provision.

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Optimal Weather Routeing Procedures For Vessels On Trans-Oceanic Voyages, Simon Calvert Jan 1990

Optimal Weather Routeing Procedures For Vessels On Trans-Oceanic Voyages, Simon Calvert

Other Faculty of Science and Engineering Theses

Three sets of algorithms are formulated for use in a variety of models :- * Ship performance algorithms. * Optimisation algorithms. * Environmental data. Optimisation models are constructed for deterministic minima, with time, fuel and cost objective functions. Models are constructed for an actual ship, (M. V. DART ATLANTIC), and realistic working solutions are obtained based on real-time weather information, simulating an actual on-board, computer based system, using dynamic programming. Several combinations of algorithm types are used in the the models, enabling comparisons of effectiveness. Thus, the ship performance algorithms incorporate severally; simple ship speed loss curves, ship resistance, ship …

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Topographically Induced Internal Waves And Enhanced Vertical Mixing In An Estuary, Darrell Richard Mark Sturley Jan 1990

Topographically Induced Internal Waves And Enhanced Vertical Mixing In An Estuary, Darrell Richard Mark Sturley

Other Faculty of Science and Engineering Theses

Stratified tidal flow over topographic features has often been thought to give rise to enhanced vertical mixing in estuaries. So far no estimates have been made of the transfer of energy from the barotropic tide to internal waves, and subsequently to increased potential energy of the water column. Observations have been made over a topographic depression at Cargreen in the Tamar Estuary. This work shows clearly the formation and evolution mechanisms for internal waves on the thermocline, on a neap and a spring tide. On a neap tide an internal wave formed as a nonlinear response to the tidal flow. …

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Probation: Politics, Policy And Practice, Tim Peter May Jan 1990

Probation: Politics, Policy And Practice, Tim Peter May

Other Faculty of Arts, Humanities and Business Theses

The aim of this study is to understand changes in the criminal justice system and their effects on policy and practice within the probation service In England and Wales. Towards this aim it utilises the techniques of participant observation, interviews, documentary research and an extensive self-completion questionnaire. The study proceeds by examining the history and politics of the Service and the relationship of these to changes in internal policy and occupational practice. More specifically, it then considers the responses of one probation area. Therefore, the study does not separate the issue of environmental effects on an organisation and how that …

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