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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

An integrated framework for environmental management and protection in Zambia

Silengo, M. January 1996 (has links)
This study identifies the major environmental issues and problems affecting Zambia and examines the current state and practice of environmental protection and management. A review of the existing legislation relating to environmental protection in Zambia is made. The relationship between the development process and the environment is explored, in particular giving an overview of the evolution of paradigms in environmental management and development. An outline of the environmental trends in sub- Saharan Africa and the environmental policy in the United Kingdom and how it relates to the framework of EC environmental policy is made. With such a background key issues have been identified to be addressed when considering environmental policy in Zambia. The mining, agricultural and tourism industries form the sectoral case studies of this study. These sectors have been selected on the basis of their dominance in Zambia's development strategy and their impact on the environment. The immense scale of the mining industry warrants its consideration; agriculture has now been given priority as the sector with the highest potential in the overall economy and; in diversifying the economy, tourism development is emerging as one of the most important sectors. The study recognises that the absence of definite crosssectoral guidelines for environmental resources management and a general paucity of information on the environment have been major constraints for the development of environmental protection strategies in Zambia. This has been due to insufficient institutional support for sustained research and monitoring of the environment. Therefore, the study mak?s general sectoral recommendations for addressing the environmental problems identified in the study.
102

The CFD assisted design and experimental testing of a wing-sail with high lift devices

Atkins, D. W. January 1996 (has links)
A wingsail is a solid symmetrical aerofoil section which creates thrust in the same manner as a conventional sail. Wingsails may either be used as a sole power unit, e. g. for a yacht or catamaran, or as an auxiliary power unit on a larger craft, e. g. fishing vessels, cargo ships or passenger liners. To augment the thrust created by the wingsail, high lift devices are employed to increase both the maximum lift and the stall incidence of the aerofoil. A wingsail must be symmetrical and capable of creating an equal lift force with the flow approaching the leading edge from either side of the wing centreline, i. e. the wingsail surface must act as either the upper, or lower pressure surface. Initial experimental work proved that using a symmetrical slat as a leading edge high lift device both delayed the separation of flow over the wingsail upper surface and increased the effective camber of the aerofoil. To increase the thrust created still further, this leading edge high lift device was combined with a trailing edge high lift device, a symmetrical single slotted flap. Due to the large number of possible model configurations, a commercially available CFD package was introduced to assist with the design. A series of validation tests comparing the CFD with published and experimental results showed a qualitative agreement with these results. However, the CFD predictions were not sufficiently accurate to be used quantitatively. The computationally designed triple element model was tested experimentally. Lift, drag, pitching moment and pressure distribution measurements were taken from the model. The results of this testing showed that the triple element wingsail increased the plain wing Coax by 68% and the stall incidence by between 4* and 6'. The final triple element wingsail design also increased the thrust of a plain wingsail over the whole operating region. Thrust was increased by up to 83% at the wind angles where a wingsail is most efficient. The results also proved that a commercially available CFD package can be used as an effective and time saving tool for wingsail design.
103

Utilisation of Environmental Impact Assessment (EIA) technique in assessment of impact of human interference on natural ecology of estuaries : a case study of Mersey Estuary

Aliero, B. A. January 1994 (has links)
A conceptual study of the impacts of human activities on the natural ecology of estuaries was carried out. The Mersey Estuary was used as a case study. Environmental Impact Assessment Techniques (EIA) was used to identify and evaluate impacts generated by various activities of Man on estuaries. The study was conducted with materials and data gathered from scientific papers, documents, reports and other related literature sources. The findings of the research reveal that estuaries exist in several forms and shape. They are characterised by graded salinity ranging from marine condition (3.5%) to fresh water (0.05%) and periodic and spontaneous tidal movements. Estuaries are highly productive ecosystems and support large wildlife and fish. For many years Man has exploited estuarine resources. However, in the last two hundred years, the advent of the industrial revolution led to dramatic growth of navigation and establishment of industries close to estuarine waters. Consequently estuaries attracted large human populations which discharged sewage along with industrial effluent direct into their waters causing rapid deterioration in water quality and severe distress of the biota. The Mersey Estuary is typical of such industrialized estuaries. The level of engineering modification and the extent of pollution witnessed in the Estuary is possibly unparalleled by any other estuary in the U. K. These activities have significantly affected the ecosystem of the Mersey and the socioeconomic lif e of people living within its catchment boundary and beyond. EIA has become an important tool in environmental planning and management. I have used its principles and techniques in the identification and analysis of impacts caused by activities of Man on the Mersey Estuary. Analysis of results indicate that the construction of training wall along the sea channels and the building of the Manchester Ship Canal were most important, reducing estuarine capacity and the stabilization of the inner estuary navigation channel. The heavy organic load from sewage and industry discharged directly into the estuary caused severe deficiency of dissolved oxygen and consequent loss of fish and wildlife. The drive to clean up the Estuary started in the 1970s and so far positive changes are being recorded showing improved wildlife which reflect general improvement in the whole Estuary.
104

Business process re-engineering and organisational change : evaluation of implementation strategies

Vakola, M. January 1999 (has links)
This thesis is based on research carried out within the CONDOR project funded under the European ESPRIT programme, which is a partnership between English, French, and Swedish construction companies. The thesis aims at presenting empirical evidence and discussion that moves toward a theory of successful implementation of change initiatives such as business process re-engineering trying to identif' its main components. The thesis challenges the concept of business proàess re-engineering trying to add to the body of knowledge in this area through the development of a new business process re-engineering methodology applied and evaluated in the three case studies which were participated in the research. The research methodology used is a combination of quantitative and qualitative research methods (triangulation technique). A major element of the thesis is the empirical work carried out, in which the researcher was actively involved using the new business process re-engineering methodology. The analysis of both qualitative and quantitative results showed that the basis of a successful business process re-engineering should concern the development of some organisational characteristics, which would prepare the organisation for a more holistic form of organisational change. Finally, the thesis draws together the different problems and questions that arise in order to develop a business process re-engineering strategy, based upon the literature and empirical findings, in order to improve organisational effectiveness and help the organisations to survive in a continuously changing environment.
105

Communication across the divide : an investigation into the beliefs and behaviours of IS academics with respect to the dissemination of their work

Nevill, N. P. January 2000 (has links)
The IS field prides itself on its closeness to practice and, in recent years, has found itself under growing pressures from government and business for the improved utilisation of research results. This thesis is concerned with the beliefs and behaviours of IS researchers in UK universities with respect to the dissemination of their results. An underlying assumption of the thesis is the potential interest and relevance of IS research results to those working in organisations, based on the author's experience as an IS practitioner. The work is the first phase of a longer research programme which aims to encourage the empowerment of those engaged in IS activity through improved awareness of, and access to, such results. Both the choice of research issue and the research approach itself were informed by the IS literature, in particular Stakeholder Theory, Multiview 2 and the variety of literature based on the Multiple Perspectives approach to problem solving. A critical stance is taken throughout the work, with an holistic consideration of dissemination within the IS research. The critical perspective is promoted in the thesis through the surfacing of assumptions about the activity of IS research and the influence of its stakeholders. Insights into the area of dissemination are presented from in-depth interviews with IS leaders in UK universities, supported by the findings from a broader survey of the IS academic community. The analysis and discussion of findings explore issues from Resource- Dependence and Ethical Theory within IS research, as well as the role of the researcher and dissemination routes to IS practice. The thesis provides an evaluation of the author's learning during the research project, and the contribution of the work to IS theory and practice.
106

Saudi-American relations 1968-78 : a study in ambiguity

Odah, O. S. January 1988 (has links)
The decade 1968-78 saw three major developments in Middle East politics these were the Arab defeat in the Six-Day War in 1967, the British withdrawal from East of Suez in 1971 and the Yom Kippur War of 1973 These events stimulated the United States increasingly to involve itself in regional politics in an attempt to maintain stability and continued access to oil As a major oil producer and the one with the largest proven reserves, Saudi Arabia sought to ensure its security by trading oil for American assistance. This thesis examines Saudi-United States relations from the Six-Day War to the Camp David Agreement of 1978 and the collapse of the Shah's regime in Iran and concludes that Saudi Interests were not obtained but rather those of the U.S. secured. The thesis looks in particular at Saudi security interests, American arms sales and the political tensions produced by the pervasive Arab-Israeli conflict. It draws extensively on official documentation in both Arabic and English, while recognising the highly personal nature of Saudi political reaction to the constraints and opportunities of the period under review. In the final analysis Saudi leaders paid a very high price for a very limited commitment to their own security while the U.S. was able to maintain and enhance its political commitment to the state of Israel.
107

Petri-net-based supervisory control of discrete event systems and their ladder logic diagram implementations

Uzam, M. January 1998 (has links)
The last decade has witnessed rapid developments in computer technology, which in return, has found widespread applications in manufacturing systems, communication networks, robots etc. Such systems are called Discrete Event Systems (DESs), in which properties such as non-determinism, conflict and parallelism are exhibited. As DESs become more complex, the need for an effective design tool and its implementation becomes more important. Supervisory control theory, based on finite state machines (FSM) and formal languages, is a well established framework for the study of DESs. In supervisory control, given a model of the system and the desired system behaviour specifications, the objective is to find a supervisor (controller) such that the controlled behaviour of the system does not contradict the specifications given and does not unnecessarily constrain the behaviour of the system. In general, the classes of specifications that have been considered within the supervisory control fall into two categories: the forbidden state problem, in which the control specifications are expressed as forbidden conditions that must be avoided, and the desired string problem, in which the control specifications are expressed as sequence of activities that must be provided. In supervisory control, there are some problems when using FSMs as an underlying modelling tool. Firstly, the number of states grows exponentially as the system becomes bigger. Secondly, FMSs lack from graphical visivalisation. To overcome these problems Petri nets have been considered as an alternative modelling tool for the analysis, design and implementation of such DESs, because of their easily understood graphical representation in addition to their well formed mathematical formalism. The thesis investigates the use of Petri nets in supervisory control. Both the forbidden state problem and the desired string problem are solved. In other words, this work presents systematic approaches to the synthesis of Petri-nets-based supervisors (controllers) for both the forbidden state problem and the desired string problem and introduces the details of supervisory design procedures. The supervisors obtained are the form of a net structure as oppose to supervisors given as a feedback fiinction. This means that a controlled model of the system can be constructed and analysed using the techniques regarding to Petri net models. In particular the thesis considers discrete manufacturing systems. The results obtained can be applied to high level control of manufacturing systems, where the role of the supervisor is to coordinate the control of machines, robots, etc. and to low-level control of manufacturing systems, where the role of the supervisor is to arrange low-level interactions between the control devices, such as motors, actuators, etc. An approach to the conversion from the supervisors to ladder logic diagrams (LLDs) for implementation on a programmable logic controller (PLC) is proposed. A discrete manufacturing system example is then considered. The aim of this is to illustrate the applicability, strengths and drawbacks of the design techniques proposed.
108

Amorphous metal cores in medium frequency power transformer

Razaz, M. January 1993 (has links)
Theoretical designs have been carried out which demonstrate the possible weight and volume reductions to be obtained when using amorphous metal in place of silicon-iron for the core material in medium frequency power transformers. The amorphous metal provides such savings by its ability to operate at high flux densities without excessive core losses. The reduced core size also benefits the winding size, the overall reduction in weight and volume is particularly appropriate for rail and air borne power supply equipment. Of the various amorphous metal alloys available in ribbon form, two were selected for evaluation for the frequency band 50 to 3000 Hz. Several cores were built suitable for use in a3 kHz 20 kVA transformer using purpose built core winding facilities. The wound cores, after annealing, were subjected to a comprehensive series of tests using both sinusoidal and square wave supply voltages. The thesis contains a valuable analysis of the results obtained and related to the magnetic properties of amorphous metal. The effect of mechanical stresses has also been investigated. The wound amorphous ribbon cores were found to be slightly flexible and prone to flaking, as a consequence several methods of core protection were investigated. Temperature rise tests have been conducted on the completed cores and various methods of heat dissipation tried. The research has shown the viability of the use of amorphous metal for the cores of medium frequency power transformers.
109

Beggars can't be choosers : an ethnography of post-school transitions in a high unemployment area

Craine, S. F. January 1993 (has links)
My thesis seeks to explore and document the processes involved in the career transitions of a specific sample of unqualified minimum age school leavers drawn from a high unemployment inner city area. The main body of data was collected ethnographically between 1985 and 1990, although the original 'data-base', entrée into the field, and 'insider status' were derived from my former employment in a Youth and Community Project in the study area. The research has identified three broad patterns of labour market transition: the first involved a minority of participants and was a traditional post-school transition to primary employment; the second involved a slightly larger group in protracted transitions via combinations of experiences which included unemployment, underemployment and government schemes; the third and most common pattern involved a cyclical post-school transition described by some study participants as the 'Black Magic Roundabout'. Cyclical transitions entailed early careers in which participants became trapped on a (not so) merrygo- round of unemployment, government schemes and special programmes, youth jobs, work in the informal economy, more unemployment, schemes, and so on. Generally, this transition preceded the slide into cynicism, disillusionment and labour market withdrawal. Each of the labour market transitions reflected a complementary career pattern in terms of entry into and progress through adult domestic life. Case studies explore individual responses which were mediated by the inter-relationships between labour market and domestic career transitions and trends in government policy, the economy, local labour market conditions, housing and the family. By far the largest group among research participants were those who had moved through cyclical transitions and labour market withdrawal into long-term unemployment. My study illustrates how this group restricted social networks to others in a similar position, built on a common sense of identity and reduced commitment to the orthodox labour market. My study reveals that to those for whom employment was perceived as only a distant and diminished possibility, alternative status systems were subculturally conceived. Significantly large numbers of participants proactively explored, constructed and pursued sub- and anti-employment careers. Affiliation to the sub- and anti-employment subcultures enabled participants to offset threats to psychological well-being posed by their objective labour market positions and provided alternative routes to income, status, identity and meaning. Of all the post-sixteen progression routes, the slide into the informal economy and acquisitive criminality is the most under-researched. Detailed exploration of these nonconventional routes contributes to the contemporary understanding of post-school transitions and provides knowledge of the 'career points' through which this transition occurs.
110

Management of innovation in school technology

Toft, P. N. January 1988 (has links)
This thesis documents and evaluates two associated topics of action research in the form of case studies in school technology. Its emphasis is on the role of strategic planning in the management of innovation within this increasingly important area of the English school curriculum. The research was carried out during a period in which British industrial innovation, and its effective management, was seen to be crucial to the nation's economic well being in the face of international competition. Growing acceptance of the importance of technology in general schooling, evidenced by its inclusion in the national curriculum embodied in the 1988 Education Reform Act, is set against the interlinked cultural, epistemological and professional barriers to its acceptance as high status activity within schools. It is argued that considerable energy expenditure is required before the intentions of the Reform Act become reality, and that innovation will need to be effectively managed. The study is therefore set against a review of the literature of innovation management in three spheres: curriculum development; the diffusion of Innovations; and industrial management. The first case study examines the implementation of an innovatory interpretation of the school subject Craft, Design and Technology (CDT) within the City of Manchester Education Authority. It tests the feasibility of developing a 'concept base' approach to CDT by teachers collaborating and being supported by the authority's inspector for CDT. It concludes that the innovation in a simple form is feasible, given that certain conditions and levels of resourcing can be met, but that in a more elaborate form, the innovation is severely problematic. The turbulence and rapid change being experienced within schools in the late nineteen eighties increases the severity of these problems. The second case study describes a project carried out in the North West of England in which various local education authorities and institutions of higher education collaborated to reduce perceived severe qualitative and quantitative shortages of CDT teachers. Five project aims were tested within the research and it is concluded that under certain conditions they are achievable, but that collaboration between institutions with different goals and customs is difficult, and that the quality of management information available to CDT staffing decision makers in the region W4S insufficiently accurate or sophisticated for effective innovation to proceed. In conclusion, certain generalisations are made relating to the effective management of innovation in school technology. These include: the inevitability of transactional distortion of objectives in the journey from intention-to outcome; the need to formulate and understand objectives and defend them from this drift, albeit in flexible ways; the need for incentives and central control in such collaborative endeavours; and finally the need for simple and effective communications within innovations.

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