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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.
181

Atividades humanas e mudanca climatico-ambientais: um arelacao inevitavel / Human activities and climate and environment changes: an inevitable relation

SANCHEZ, ARETHA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:20Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
182

Atividades humanas e mudanca climatico-ambientais: um arelacao inevitavel / Human activities and climate and environment changes: an inevitable relation

SANCHEZ, ARETHA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:20Z (GMT). No. of bitstreams: 0 / A interferência antrópica no meio ambiente e conseqüente alteração do clima, é hoje um consenso. Esta interferência climática se dá de forma local, regional e, conjuntamente com os gases de efeito estufa, de forma também global. Essa alteração climática, de maneira reversa, interfere por sua vez, no meio ambiente. Tal ciclo de interferências se processa sob várias formas e resulta em várias conseqüências. Porém o chamado Aquecimento Global é, certamente, o efeito de conseqüências globais de maior impacto. A causa principal do aumento da temperatura (Efeito Estufa) está no uso intensivo que se faz de energéticos fósseis. Assim, para minimizar as mudanças climáticas deve-se focar o esforço principalmente em ações que visem à diminuição, substituição e o uso mais eficiente dos energéticos fósseis. Olhando para o passado, parece que os antigos agricultores podem ter lançado gases estufa desde milênios atrás, alterando de maneira lenta, mas significativa, o clima do planeta muito antes do que na Era Industrial. Confirmada essa teoria, suas conseqüências seriam decisivas para a história do homem na Terra. Por exemplo, as temperaturas atuais de partes da América do Norte e Europa poderiam ser até 4 graus Celsius menores, o suficiente para inviabilizar nessas áreas, a agricultura e, conseqüentemente, o desenvolvimento humano e histórico dessas regiões. Este trabalho tem como foco principal fazer uma retrospectiva sobre algumas culturas que colapsaram frente a problemas ambientais e fazer um histórico das atividades humanas ao longo do tempo, desde os primórdios do homem até a Revolução Industrial, notadamente com o que diz respeito à vi agricultura e pecuária, no sentido da sua interferência na dinâmica natural do clima global e no meio ambiente. Mostrando, através de comparações de dados e inferências, que as emissões dessas atividades tiveram uma magnitude até significativa, comparativamente as mudanças induzidas após a própria Revolução Industrial. Demonstra-se, também, que essa interferência climático-ambiental era inevitável, no sentido que a evolução humana deveu-se a essas mesmas atividades. Outro ponto importante é uma reflexão sobre como a evolução humana (e conseqüentemente sua ciência e tecnologia) irá, porventura, encontrar as soluções dos problemas causados por essas mudanças climáticas e ambientais e a importância, neste contexto, para as soluções de problemas de ordem social / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
183

A multi-disciplinary optimisation model for passenger aircraft wing structures with manufacturing and cost considerations

Wang, Lina January 2000 (has links)
In traditional aircraft wing structural design, the emphasis has been on pursuing the minimum weight or improved performance. The manufacturing complexity or cost assessments are rarely considered because it is usually assumed that the minimum weight design is also the minimum cost design. However, experience from industry has shown that this is not necessarily the case. It has been realised that in the cases where no manufacturing constraints are imposed, the extra machining cost can erode the advantages of the reduced weight. As manufacturing cost includes material cost and machining cost, whilst reducing weight can reduce the material cost, if the manufacturing complexity increases greatly as a result the overall cost may not go down. Indeed, if the manufacturing complexity is not checked, the machining cost could increase by more than the amount by which the material cost reduces. To enable the structural manufacturing complexity to be controlled, manufacturing constraints are established in this thesis and integrated into the optimisation of the aircraft wing structural design. As far as the manufacturing complexity is concerned, attention has been paid to both 3-axis and 5-axis machining. The final designs of optimisations with manufacturing constraints prove the efficiency of these constraints in guiding the design in the manufacturing-feasible direction.
184

Development of a Life Cycle Impact Assessment procedure for Life Cycle Management in South Africa

Brent, Alan Colin 15 September 2004 (has links)
Competitive industries in the manufacturing sector have a holistic Life Cycle Management (LCM) view of business practices. Life Cycle Assessment (LCA), which forms part of the LCM approach, is increasingly used as a decision support tool in the South African manufacturing industry. The Life Cycle Impact Assessment (LCIA) phase of the LCA tool has been standardised within the ISO 14000 family and aims to quantify the environmental impacts of economic activities. A number of LCIA methodologies have been developed in Europe, which can be applied directly when life cycle systems are assessed. The LCIA procedures that are most commonly used in the South African manufacturing industry include the CML, Ecopoints, EPS and Eco-indicators 95 and 99 procedures. The five European methods are evaluated based on the applicability of the respective classification, characterisation, normalisation and weighting elements for the South African situation. The evaluation and comparison is further based on a cradle-to-gate Screening Life Cycle Assessment (SLCA) case study of the production of dyed two-fold wool yarn in South Africa. Shortcomings are identified with the European methodologies in the South African context in terms of comprehensiveness and modelling approaches. A LCIA framework and calculation procedure, termed the Resource Impact Indicator (RII) model, is subsequently proposed for South Africa, which is based on the protection of four natural resource groups: water, air, land, and mined abiotic resources. A distance-to-target approach is used for the normalisation of midpoint categories, which focuses on the ambient quality and quantity objectives for the four resource groups. The quality and quantity objectives are determined for defined South African Life Cycle Assessment (SALCA) regions and take into account endpoint or damage targets. Following the precautionary approach, RIIs are calculated for the resource groups from conventional Life Cycle Inventories (LCIs). The calculation of the RIIs ensures that all natural resources that are important from a South African perspective are duly considered in a LCIA. The results of a LCIA are consequently not reliant on detailed LCIs and the number of midpoint categories that converge on a single resource group. The proposed model is evaluated with the SLCA wool case study. The case study establishes the importance of region-specificity, for LCIs and LCIAs. The proposed LCIA model further demonstrates reasonable ease of communication of LCIA results to decision-makers or managers. Subjective weighting values for the resource groups are also proposed, based on survey results from manufacturing industry sectors in the South African automotive value chain, and the expenditure of the South African national government on environmental issues. The subjective weighting values are used to calculate overall Environmental Performance Resource Impact Indicators (EPRIIs) when comparing life cycle systems with each other. The EPRII approach is applied to a specific LCM problem in the South African context, i.e. evaluating and comparing environmental performance for supply chain management purposes in the developing country context. Thereby, RIIs are provided for key Cleaner Production process parameters in the South Africa context: water usage, energy usage, and waste produced per manufactured product. / Thesis (PhD (Engineering and Technology Management))--University of Pretoria, 2005. / Graduate School of Technology Management (GSTM) / unrestricted
185

Risk management in the application of the systems development life cycle

Cronje, Danie 28 September 2011 (has links)
The purpose of this report is to make a contribution to the South African Post Office Technology division. This is achieved by starting with a number of fundamental theoretical principles in related disciplines. Risk management is proposed to the management in an attempt to increase the success rate of information technology projects. Concentrating on methodology is not the only answer. Management should accept that risks are part of the development process and should be managed. Even though risks appear throughout the development life cycle, management should realise that the starting phase of any systems development life cycle is one of the most crucial events. There is a saying in Afrikaans: "Goed begin is half gewin". Meaning that if a project starts on a healthy basis, the rest should be clean sailing. This report should provide a useful starting point for further empirical analysis since it provides an overall theoretical framework for the systems development life cycle. / Dissertation (MBA)--University of Pretoria, 2011. / Graduate School of Management / unrestricted
186

A process systems methodology for environmental impact minimization

Stefanis, Stavros Konstantinou January 1997 (has links)
No description available.
187

The development of preliminary design and assessment methodologies for enhanced combat aircraft supportability

Whittle, Richard Geoffrey January 1997 (has links)
No description available.
188

Evaluating the Impact of the Pac Success Academy on Court-Mandated Families

Unknown Date (has links)
This study compared the effectiveness of a multi-family treatment program on court-mandated families and voluntary families. The participants (n=109) included 36 voluntary families and 38 mandated families. Demographically, the families in each group were similar in age and education level but were somewhat dissimilar in their ethnicity and presenting issues. Participants completed a pre and posttest questionnaire, the Family Assessment Measurement III, which revealed that both groups improved on overall family functioning and had high attendance and graduation rates. The implications of these findings for practitioners are presented. / A Dissertation submitted to the Department of Family and Child Sciences in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester, 2007. / April 16, 2007. / Court-ordered Therapy, Multifamily Therapeutic Groups, Court-mandated Therapy, Psycho-educational Groups, Multifamily Groups / Includes bibliographical references. / Ann K. Mullis, Professor Directing Dissertation; Nicholas F. Mazza, Outside Committee Member; Mary W. Hicks, Committee Member; Ronald L. Mullis, Committee Member.
189

Using preference/utility curves in the creation of a computer program for decision evaluation display analysis

Rice, Pamela F. 26 January 2010 (has links)
Master of Science
190

Navy positive displacement pump standardization study

Cohen, Edward L. 30 March 2010 (has links)
see document / Master of Science

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