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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.
281

An investigation of a waste minimisation club for the metal finishing industry.

Thambiran, Namo. January 2002 (has links)
Take care how you place your moccasins upon the earth, step with care, for the faces of the future generations are looking upfrom the earth waitingfor their turnfor life - Lyoru, 1988 Increasing levels of pollution and the increase in demand for water and other resources by industry led to a number of policies and regulations being developed and revised in South Africa. According to the Constitution of the Republic of South Africa (Act 108 of 1996), everyone has the right to an environment that is not harmful to health or wellbeing. In order to have the environment protected and sustained for future use, it became necessary to move away from the traditional fragmented approach to pollution and waste management and focus on an integrated strategy aimed at achieving a balance between ecological sustainability and socioeconomic development. In the Durban Metropolitan Area (DMA) , the Durban Metropolitan Council (Metro) incorporated pollution prevention in their bylaws, which contained stringent discharge limits for heavy metal concentrations. This posed a potential problem for metal fmishers who were concerned about complying with these discharge standards. In addition, the metal finishing industry was considered to be a significant contributor to the pollution load in the DMA, and therefore needed to find suitable solutions to dealing with environmental problems, especially waste management. Waste minimisation was believed to be a good tool for this industry to utilise in order to reduce its pollution load. It was seen from the literature and case studies from international initiatives that waste minimisation results in an improvement in process efficiency and reductions in production costs and environmental impacts, generally at minimal costs. A waste minimisation club was initiated for the metal finishing industry in the DMA in June 1998. The club consisted of twenty-nine members of which the majority were small and medium sized companies. The club was run over a period of thirty months. A core group of sixteen companies actively participated in the activities of the club. During the period of investigation, a total of 391 waste minimisation options were identified for club members and 147 of these options were implemented. This resulted in a total financial saving in excess of R 4 million for the duration of the club's existence. The saving represents combined savings in water, chemicals, metals, energy, effluent treatment, and waste disposal. Corresponding environmental benefits were achieved including a reduced demand for water, reduced toxicity of effluent from chemical and metal reduction, and a reduction in energy requirements. Four companies were investigated in detail and presented as case studies. These companies showed that the payback on implementing waste minimisation options was mostly immediate. The size of the companies was not critical in determining the level of success from running waste minimisation programmes. Success depended mainly on commitment from companies and motivation of project champions. It was found that the greatest barriers to implementing waste minimisation, as identified by companies, were a lack of time, resources, and commitment. Companies joined the club mainly for benefit of reducing costs and complying with legal standards. Aside from successfully raising awareness and promoting the concept of waste minimisation, the waste minimisation club also resulted in an improvement in the relationship between the metal finishing industry and the Metro, and among club members. Based on the results achieved by club members, and from managing the club, it was evident that the club was effective in promoting waste minimisation in industry. For the future running of clubs, it is recommended that waste minimisation assessment training be given to all employees of a company. It would also be more useful if companies reported savings on a more regular basis and more formally. In addition it is recommended that club membership should be limited to between ten and fifteen companies to facilitate improved management of the club. / Thesis (M.Sc.Eng.)-University of Natal,Durban, 2002.
282

Vulnerability to HIV amongst African people in rural areas : the Thusano project / Kediemetse Desireé Victoria Seyama

Seyama, Kediemetse Desireé Victoria January 2006 (has links)
Research has outlined numerous factors that impact on HIV risk behaviours of African people. These include a history of sexually transmitted diseases, number of sexually transmitted diseases, number of sexual partners, the perceived behaviour of peer groups and perceived vulnerability to HIV. Little is known regarding the factors that promote perceptions of vulnerability to HIV and the role this constraint plays in the maintenance of AIDS risk-reduction practices among African people in rural areas. This research paper gives an overview of the vulnerability to HIV among African people in a rural area. The information has been collected in the Kuruman district. The multi-disciplinary survey was undertaken with one of the objectives to investigate the vulnerability to HIV amongst African people in a rural area. The aim was achieved by means of a study of the relevant literature and through empirical research. The available literature on the subject was consulted to determine whether any research has been conducted in this field. The empirical research was conducted to confirm previous research findings. In this study the survey method was used as a systematic fact gathering procedure. Data was gathered by means of an interview schedule. The researcher administrated the schedules by conduction personal interviews with respondents. In this research, which forms part of the Thusano project, the focus was on the vulnerability to HIV/AIDS of people living in a rural area in the Kuruman district. The Thusano project forms part of a multi-disciplinary research project of the Potchefstroom Campus of the North-West University, entitled the Social-motor Empowerment of Families in Impoverished Circumstances under the Leadership of Professor A.E. Pienaar of the School of Biokinetics, Recreation and Sport Science. "Thusano” means to help each other and this is a Nelson Mandela funded project which has to address the needs of families in impoverished circumstances living in seven communities in the Kuruman district. The project is driven by the social worker, Ms Tineke Uys, and field workers. An early childhood programme aiming at school readiness has been implemented by them. However, many other needs are identified by the social worker which they are not able to address properly, such as HIV prevention and counselling, family violence, identification of motor delays and other health related problems. The research was conducted in seven communities of the Kururnan district with regard to 50 respondents from different households. The findings of this research reflect that there definitely are factors such as practising unsafe sex, poverty, poor education and over-crowded households that play an important role in the people's vulnerability to HIV/AIDS in the seven communities of the Kuruman district. / Thesis (M.A. (MW))--North-West University, Potchefstroom Campus, 2006.
283

Search strategies of benthic predators : an experimental and modelling study

Hill, Simeon January 1997 (has links)
No description available.
284

Tungmetaller i Mobekken : Spridning, risker och eventuella åtgärdsbehov

Waara, Stina January 2016 (has links)
This report details the study of a freshwater stream carrying high doses of heavy metals into an already affected fjord. The purpose is to find out how the measured levels of heavy metals vary across the industrial area, and if these levels are posing an environmental or health threat to the surroundings. According to the water directive of the European Union, all waters should be protected in order to reach ’good status’, and deterioration should be prevented. To keep track of the status of waters, environmental quality standards (limit values known as EQS) are used by Norwegian environmental authorities to indicate pollution levels. All measured contents in this report are therefore compared with EQS or similar limit values. New water samples were taken along the stream and in the soil and sediments during the spring of 2016. The measured levels were then compared with older water samples, and showed clear variations across the industrial area for most of the substances. For some substances, high levels of pollution were found in the soil, sediment and water. Despite this, most measured heavy metals pose no threat environmentally or health-wise due to the very alkaline water in the stream, likely to leave most metals nonbioavailable. Although the stream is heavily loaded with various heavy metals, its lack of finer matter prevents metals from binding to organic ligands, allowing the stream to become more of a transportation means than a place for accumulating metals in the soil and sediments.
285

Fault tolerant ATM LAN/LAN internetworking for connectionless data services and their performance evaluation

Odeh, Abdel-Rahman M. M. January 1995 (has links)
No description available.
286

The changing importance of OCA arguments in the national discussions about euro accession in the new EU member-states of Central and Eastern Europe in times of crisis

Slezák, Milan January 2013 (has links)
The Eurozone has been the object of much controversy recently. Both on the member-state and on the EU level, policies are being made to cope with the many problems of the Eurozone. In this paper we state that academic economics is often unable to give the right advice for policymakers in the case of the Eurozone crisis, because this is a new situation where academics are disagreeing fundamentally about the best remedy for the problem. We come to this conclusion by first showing how one of the most prominent theories about monetary unions (the Optimum Currency Area theory) is unable to give any good advice to policymakers. After that we make a country-comparitive study between the ten new EU members in Central and Eastern Europe that joined in 2004 and 2007, which shows us that these countries respond fundamentally different on the Eurocrisis and that these reactions are more based on political and public support and national economic performance than on formal academic economics.
287

Future of the U.S.-Japan security alliance [electronic resource] : foundation for a multilateral security regime in Asia? / Future of the United States-Japan security alliance

Allen, Keith W. 06 1900 (has links)
The U.S.-Japan Security Alliance was the foundation of the United States' bilateral alliance system during the Cold War. The alliance suffered severe strains in the immediate aftermath of the Cold War primarily due to the loss of its primary mission, containment of Soviet expansion. The terrorist attacks of September 11, 2001 breathed new life into the alliance. Japan quickly joined in the anti-terrorism coalition, providing logistical support to U.S. forces involved in the War on Terrorism. North Korea's October 2002 admission of a covert nuclear weapons program also changed the strategic dynamic for Japan, pushing it towards "normal" nation status. Multilateralism in Asia developed a life of its own during the 1990's. Numerous multilateral organizations were created to help resolve regional security issues. China is attempting to use multilateral security forums as a means to balance against U.S. regional power. Japan also proposed developing a new multilateral security regime in the Asia-Pacific. This thesis examines issues related to the future of the U.S.-Japan Security Alliance and the possible emergence of a new multilateral security regime in the Asia-Pacific. The United States should enhance the U.S.- Japan Security and lead the way on developing a new multilateral security regime for the Asia-Pacific. / US Navy (USN) author.
288

A robust wide area measurement based controller for networks with embedded HVDC links

Agnihotri, Prashant 12 August 2016 (has links)
The advent of Wide-Area measurement Systems has spurred interest in the use of non-local feedback signals for power swing damping control. Although damping can be improved through generator excitation systems, dc links and other grid connected power electronic converters, the full potential of wide-area measurements can be realized by coordinating the strategies used for multiple controllable devices in a grid. These strategies also need to be robust to partial or complete loss of communication, changes in operating points, topology and equipment outages, improve damping of all the controllable swing modes, and have adequate stability margins to avoid destabilization of untargeted modes. This thesis investigates a control strategy for multi-infeed and multi-terminal (also referred to as multiple embedded dc links in this thesis) dc links using local frequency difference signals as well as the frequency difference signals obtained from other dc links. This strategy combines the advantages of the local frequency difference signal with the additional degrees of freedom provided by the use of non-local frequency difference signals, to achieve targeted and enhanced swing mode damping for the poorly damped modes. Since the strategy uses only a limited set of non-local signals, the signals may be directly communicated to the dc links without having to be centrally collated with other system-wide measurements. The key aspect of the proposed strategy is the use of a symmetric positive definite (spd) gain matrix. This results in enhanced damping for all controllable swing modes. Furthermore, loss of communication between the dc links does not destroy the symmetric positive definiteness and the gain elements can be tuned to selectively enhance damping of poorly damped modes. Eigenvalue sensitivity analysis and case studies on a 3 machine 9 bus and 16 machine 68 bus system with multiple HVDC links are presented to demonstrate the key attributes and the effectiveness of this strategy. / October 2016
289

Dimensiones sociales de los problemas ambientales en la Región Metropolitana de Chile, a través de un análisis de caso.

Aedo, María Paz January 2005 (has links)
En esta línea, el trabajo que se expone a continuación constituye una investigación cualitativa y exploratoria, que analizará dos problemas ambientales en el ámbito local, teniendo en cuenta su dimensión política y social. Para ello se identificarán las características de los problemas, los actores involucrados y los mecanismos desarrollados para su comprensión y abordaje, desde la perspectiva de las organizaciones ciudadanas, el sector público y el sector privado. Se tomará como referencia una comunidad de la Comuna de Cerro Navia, conocida como la Villa Montijo Norte, que está en contacto directo con dos focos de conflicto ambiental: contaminación atmosférica y contaminación por residuos sólidos domiciliarios . Se han escogido estos dos conflictos por su carácter crítico en términos de los problemas ambientales y territoriales que afectan a la Región Metropolitana desde hace al menos dos décadas.
290

Localization and parcellation of the supplementary motor area using functional magnetic resonance imaging in frontal tumor patients

Vera, Matthew Ramon 18 June 2019 (has links)
Neurosurgery is an effective method for prolonging life and improving outcomes for patients with brain tumors. However, this option bears the risk of damaging areas of eloquent cortex, areas associated with motor and language tasks that, when lesioned, will result in a functional deficit for the patient. Functional magnetic resonance imaging (fMRI) is a valuable tool in the localization of eloquent cortex for preoperative neurosurgical planning. Through use of this modality of functional neuroimaging, the neurosurgeon can adjust the surgical trajectory to incur the least amount of damage to sites of functional activity. The supplementary motor area (SMA) is one such site of eloquent cortex that must be visualized preoperatively due to the risk of postoperative deficit with lesions in this area. However, due to both the effects of tumor pathology and naturally occurring interindividual variability, the SMA’s location and functional fingerprint can be highly variable. We present a study in which patients with frontal tumor (n=46) underwent task-based fMRI for motor and language network mapping. The patient-specific functional data were normalized and evaluated using ROI analysis to illustrate group-level activation patterns within the SMA during the language and motor tasks. The results illustrate a distinct pattern of activation including a rostro-caudal organization of language and motor activation, overlapping extent cluster volumes throughout the two functional subdivisions of the SMA, the pre-SMA and SMA proper, and discrete activation foci.

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