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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.
21

A technological capabilities perspective on catching up : the case of the Chinese information and communications technology industry

Long, Vicky January 2014 (has links)
This dissertation provides a capability creation perspective on the story of China’s technological catching up, or resurgence, if viewed from a broader historical perspective. Since the first Asian tigers caught up to modern technological standards (e.g., South Korea, Singapore), two schools of thought have dominated causal explanations (Nelson and Pack, 1999). The first perspective is the conventional accumulation approach, which attributes the major share of growth to the accumulation of physical and human capital, and views learning as a more-or-less automatic byproduct of those investments. The second perspective is the assimilation approach, which emphasizes the arduous learning, risk-taking entrepreneurship, and innovation that is involved in the process and argues that the former proposition neglects this aspect of the endeavour and may therefore lead to erroneous estimates. This dissertation focuses on the second school of thought. Compared to the first-tier Asian tigers, the second-tier tigers, of which China is representative, pose many challenges to the assimilation approach. First, the sheer size of the country results in an unusual scale and scope of activities and interactions in any field. Second, the long history of civilization in China suggests that many modern phenomena have historical roots that are unknown to outsiders and invisible and complex to insiders. The present study aims to contribute a small piece of the puzzle to our understanding of the big picture. By providing an in-depth study of the Chinese information and communication technologies (ICT) sector, this study explores changes that have occurred in the three key building blocks of capability creation; specifically, the sourcing, generation, and appropriation of technological knowledge. A qualitative case study approach was employed for the main, empirical part of the study, which consists of extensive firm-level interviews. Complementary statistical data, including patent data and historical archives, were used to provide context and a deeper look into the study topic. The results are described in five articles. The first article presents establishing overseas research and development (R&D) laboratories as one of the major learning methods for overcoming disadvantages related to dislocation from technology sources and advanced markets. This approach allows China to search for industry-relevant scientific knowledge rather than adopting ready-made technologies introduced by western multinational enterprises in China. The second article describes the modularity-in-design approach, which opens new windows of opportunity for technological advancement. The lack of essential intellectual property rights (IPRs) acts as a key inducement and a factor-saving bias that influences the direction of innovation. When both (international) competitiveness and learning are involved in the catching-up process, the development of industry-wide capability becomes a particularly vital aspect of indigenous innovation. The third article describes the geographic consequences of historically planted industrial capabilities in China’s inland regions, which impact the absorption of different types of industrial knowledge. Fields of industry that are densely populated with patents- IPR thickets- represent a novel situation that was not experienced to the same extent by nations whose technological development occurred earlier. This thesis dedicates two articles to this dimension of knowledge appropriation. The fourth article describes the duality of Chinese ICT patenting, and the fifth article identifies an ambidextrous strategy that depends on where the major competition emerges. In general, the decision to patent and the extent of patenting are determined by four factors: a) the distance to the frontier (Aghion et al., 1997) particularly for technology; b) the nature of the technology (Teece, 1986), but with a rural extension in the case of China; c) the specificities of information (Arrow, 1962) that are embodied in a firm’s origins in China; and d) the supporting institutions that co-evolve in that process. Learning proceeds at different levels: that of individuals, firms, industries, and nations.   This dissertation provides an industry-level perspective on learning and innovation-based technological advancement. / from developing economy to global high-tech competitiveness - the case of Chinese ICT expansion
22

A method for developing a Triple-Bottom-Line business case for the implementation of alternative fuels and technology

Thiets, Robert Clyde 13 May 2008 (has links)
Alternative fuels and technologies for truckload carriers can provide significant environmental and social benefits over traditional heavy duty diesel vehicles by reducing petroleum-based fuel consumption and vehicle tailpipe emissions. These alternative fuels and technologies, however, often carry a cost premium or require significant capital investment. Dedicating vehicles, equipment, and infrastructure to an alternative fuel or technology also represents a significant risk in the extremely volatile trucking business. A Triple-Bottom-Line analysis, which includes economic, social, and environmental impacts of an alternative fuel or technology will strengthen the business case by incorporating the benefits of emissions reduction. A stronger business case will promote the use of alternative fuels and technologies while mitigating the risk. This thesis proposes a method for identifying alternative fuels and technologies that provide the best Triple-Bottom-Line benefit and provides a structure for modeling the emissions of the target application, quantifies the value of emissions reduction, and constructs a Triple-Bottom-Line business case. The Triple-Bottom-Line business case proposed by this method is incremental. It presupposes an existing or planned truckload carrier business already exists and only investigates the changes which occur with implementation of an alternative fuel or technology. This method may be useful for any carrier business or any company with an extensive shipping and logistics network. A case study, which was created for large automotive manufacturer, details the Triple-Bottom-Line business case for an on-site compressed natural refueling system and vehicles.
23

The socio-economic efficacy of improved wood stoves upon two non-electrified, low income peri-urban areas of Pietermaritzburg, South Africa /

Mabaso, McWilliam Chipeta. January 2009 (has links)
Thesis (M.Soc.Sc.) - University of KwaZulu-Natal, Pietermarizburg, 2009. / Full text also available online. Scroll down for electronic link.
24

Análise por impedância eletroquímica 'on line' de conjuntos eletrodo/membrana (MEA) de células a combustível a membrana polimérica (PEMFC)

SANTOS, ANTONIO R. dos 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:31Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP / FAPESP:03/08041-6
25

Análise por impedância eletroquímica 'on line' de conjuntos eletrodo/membrana (MEA) de células a combustível a membrana polimérica (PEMFC)

SANTOS, ANTONIO R. dos 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:53:55Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:31Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho apresenta resultados de estudos e caracterizações de Conjuntos Eletrodo/Membrana (MEAs) de Células a Combustível a Membrana Polimérica (PEMFC). Algumas condições de operação de células e diferentes processos de produção de MEA foram investigados. A técnica de Espectroscopia de Impedância Eletroquímica (EIE) (em situ - 0 a 16 A) foi usada \"on-line\" como uma ferramenta de diagnóstico, relativa ao desempenho de célula. As medidas de EIE foram feitas através do Sistema de EIE para células a combustível FC350 (GAMRY), junto a um PC4 Potentiostato/Galvanostato e conectado à carga dinâmica (TDI) para experimentos de EIE \"on-line\" (100 mHz - 10 kHz, dU = 5 mV). MEAs com 25 cm2 de área ativa, usando eletrocatalisadores PtM/C 20 % (M = Ru, Sn ou Ni) fabricados usando o Método de Redução por Álcool (MRA). A tinta catalítica foi diretamente aplicada no Tecido de Carbono (GDL) e este prensado na membrana de Nafion® (105). MEAs usando eletrocatalisadores Pt/C e PtRu/C 20 % da E-TEK foram fabricados para comparação. Todos os cátodos foram confeccionados com Pt/C 20% da E-TEK. Foram fixadas as concentrações de metal nobre em 0,4 mg Pt.cm-2 no anodo e 0,6 mg Pt.cm-2 no catodo (E-TEK). Diagramas de Nyquist dos MEAs com Pt/C e PtRu/C da E-TEK ou PtM/C MRA apresentaram as mesmas resistências de ôhmicas para os MEAs. Este fato pode ser explicado por supressão de aglomerados durante o processo de preparação do MEA ou pela homogeneidade do eletrocatalisador ancorado ao carbono. Também pôde ser observado, a baixas densidades atuais que há uma diferença de desempenho significante entre o eletrocatalisadores da ETEK e os preparados pelo MRA. Os resultados das curvas de polarização confirmaram que PtM/C MRA apresentara um aumento de atividade para as células alimentadas com metanol e etanol. A técnica de EIE se mostrou eficiente para a avaliação do método de preparação dos MEAs e do desempenho da célula, os resultados de EIE mostraram uma coerência na escolha do modelo do circuito elétrico para os MEAs utilizando hidrogênio, metanol e etanol. Esta coerência indica que outras resistências não consideradas no modelo não são relevantes na resistência total dos MEAs. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP / FAPESP:03/08041-6
26

The contribution of renewable energy technologies to sustainable community development in Rusitu Valley, Zimbabwe

Mavindidze, Zororo January 2012 (has links)
Magister Artium (Development Studies) - MA(DVS) / This exploratory study is based on the case of the Rusitu Valley, a low income rural community in Zimbabwe. Data was collected using largely qualitative methods and quantitative methods were used to obtain supportive descriptive statistics. Information elicited from focus group discussions conducted with members of the Rusitu Valley community as well as responses obtained from a brief structured questionnaire were used to abstract the Rusitu Valley as a complex adaptive system. Input from in-depth interviews with government representatives in energy policy, local government and non-governmental organisations as well as a review of secondary sources was used to support the analysis and confirm the contextual validity of the study. This study revealed that there is intimate connection between renewable energy technologies and sustainable community development. A key finding was that the contribution of renewable energy technologies in Rusitu Valley is mostly towards the economic dimensions of the community and is relatively limited with regard to social and environmental dimensions. Therefore, this study concluded that renewable energy technologies have not sufficiently contributed towards sustainable community development in the Rusitu Valley. This study also found that the contribution of renewable energy technologies is constrained not only by internal limitations but also external factors. A conclusion drawn from this study was that effective contribution of renewable energy technologies towards social, economic and environmental facets can be enhanced through mainstreaming of renewable energy in policy and planning, as well strengthening institutions and local capacity which would have the overall effect of sustainable community development in low income communities
27

Comparação entre os meios filtrantes areia e nãotecido sintético na eficiência da filtração lenta para tratamento de água / Comparision between sand filter media and non-woven synthetic fabric in the efficicency of slow filtration as water treatment

Santos, Flavia Ferreira de Souza dos, 1985- 29 August 2018 (has links)
Orientadores: José Euclides Stipp Paterniani, Túlio Assunção Pires Ribeiro / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-29T00:00:03Z (GMT). No. of bitstreams: 1 Santos_FlaviaFerreiradeSouzados_D.pdf: 6754875 bytes, checksum: 9a804a4e184846e60d2063d6b1aa1326 (MD5) Previous issue date: 2015 / Resumo: O nãotecido sintético é um material de fácil obtenção e baixo custo, cujo uso na filtração lenta juntamente com areia acarretou em resultados satisfatórios, em termos de qualidade de água produzida e facilidade de operação. Esta pesquisa teve como objetivo avaliar o desempenho de um filtro lento com meio filtrante constituído exclusivamente por nãotecido sintético em diferentes espessuras e compará-lo ao desempenho de um filtro lento de areia tradicional. Construiu-se um sistema piloto de filtração em que os dois filtros lentos operavam em paralelo sob influência de três taxas de filtração (3, 6 e 9 m3.m-2.dia-1). No decorrer das carreiras de filtração foram monitorados a evolução da perda de carga de cada filtro, os parâmetros físico-químicos e bacteriológicos da água bruta e água tratada pelo filtro de areia e por cada uma das 12 espessuras (entre 1 e 40 cm) do filtro de nãotecido. O filtro lento de nãotecido proporcionou carreiras de longa duração, quando comparado ao filtro de areia, além de reduzir a frequência e a complexidade do processo de limpeza do filtro. A formação da schmutzdecke foi observada na camada superficial do filtro de nãotecido, o qual teve período de amadurecimento semelhante ao filtro de areia, aproximadamente 15 dias. O desempenho satisfatório do filtro lento de nãotecido abrangeu as três taxas de filtração avaliadas. Em termos de remoção de cor aparente e turbidez da água bruta, atendeu os padrões de potabilidade de água designados pela legislação vigente. E, em termos de remoção de bactérias heterotróficas, coliformes totais e E. coli, o filtro de nãotecido alcançou eficiência superior a 99,5%, estatisticamente similar ao filtro lento de areia. Os resultados obtidos indicam que a espessura ótima de nãotecido sintético para remoção de cor aparente e turbidez da água seria de 25 cm, e sugerem que a espessura de 15 cm de nãotecido seria suficiente para remoção de bactérias, com possibilidade de emprego de taxa de filtração considerada elevada para o tratamento por filtração lenta (9 m3.m-2.dia-1). Desta forma, concluiu-se que o meio filtrante constituído exclusivamente por nãotecido sintético de 25 cm de espessura tem potencial para substituir a areia no tratamento de água por filtração lenta, uma vez que obteve desempenho similar ao filtro lento de areia, além de simplificar os procedimentos operacionais e de manutenção do filtro / Abstract: Non-woven synthetic fabric is an easily available and low-cost material which has brought satisfactory results in terms of both the quality of produced water and its operational value. The aim of this research is to assess the performance of a slow filter made up exclusively of non-woven synthetic fabrics of a number of different thicknesses and to compare it to that of a traditional sand filter. A pilot filtering system was built where the two slow filters operate in a parallel way under the influence of three filtering rates (3, 6 and 9 m3.m-2.d-1). Along the filtering runs the evolution of the headloss and the physical-chemical and bacteriological parameters of both raw water and water treated through the 12 thicknesses (ranging from 1 to 40 cm) of non-woven were monitored as well as that filtered through sand. The slow non-woven filter yielded long-term runs when compared to the sand filter, as well as reducing the frequency and complexity of the filter¿s cleaning process. The formation of schmutzdecke was observed on the superficial layer of non-woven filter, a process which had a similar maturing period to that of the sand filter, approximately 15 days. The satisfactory performance of the slow non-woven synthetic fabric filter covered all three filtering rates. In terms of the removal of apparent color and turbidity of raw water it met the drinkability standards set by the existing legislation. In terms of the removal of heterotrophic bacteria, total coliform and E. coli the non-woven filter obtained an efficiency level above 99,5%, statistically similar to the slow sand filter. The results indicate the optimal thickness of non-woven synthetic fabric for apparent colour and turbidity removal to be 25 cm, and suggest that a 15cm thickness would be enough to remove, with the possibility of using filtering rates considered elevated by slow filtering treatment standards (9 m3.m-2.d-1). Therefore, it concludes that the filter medium constituted exclusively of 25-cm-thick non-woven synthetic fabric has the potential to substitute sand in slow-filtering water treatment once it has obtained similar performance to the slow sand filter / Doutorado / Agua e Solo / Doutora em Engenharia Agrícola
28

A review of appropriate energy technologies for household use in underdeveloped areas in South Africa

Law, Stephen Mark January 1991 (has links)
The development of technologies and structures providing energy for household use in South Africa have for many years been dominated by the needs of "white" households. While these needs have been comprehensively met through cheap and efficient energy supplies, the needs of those in the "homelands" and townships have effectively been ignored. Thus, for roughly two-thirds of the population in South Africa, the struggle to meet basic energy needs for cooking, water heating, space heating and lighting is time consuming and expensive. The planning of a national energy strategy for the future can no longer overlook the energy needs of underdeveloped areas. While the immense task of building institutions and techniques for providing all with adequate and affordable energy supplies will require substantial technical intervention and a large amount of capital, ignoring these problems will incur even greater political, social and environmental costs. Interest in the field of energy for underdeveloped areas has been increasing in recent years, and has led to research on various appropriate energy technologies and the highlighting of energy problems in various locations. However, there has been no overview of experience to date, nor any comparative assessment of these technologies and their potential role in an energy supply strategy. By drawing together the body of research into one publication, this thesis hopes to provide an overview, to allow different energy technologies and supply options to be assessed and compared, and to provide a starting point for debate on suitable energy strategies for underdeveloped areas.
29

A methodology to aid in appropriate forest technology decision-making for developing countries

Grobbelaar, Frederik Russouw 03 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: Grobbelaar, F.R. 2000. A methodology to aid in appropriate technology decision-making for developing countries. M.Sc thesis. University of Stellenbosch. In the process of selecting what we believe to be suitable technology for timber harvesting and transport, economics are usually the determining factor, whether in the form of capital investment or personnel cost. Internationally we see a move towards mechanisation in forestry for various reasons: e.g., high wages, labour shortage, and occupational safety. The realities of South Africa highlights other issues requiring attention: e.g., high unemployment, skills' shortage, global competition, rampant AIDS pandemic, and a poor safety and security record. This should focus our attention on finding local solutions to the problem of finding suitable or appropriate technology to support South Africa's quest for sustainable development. This thesis attempts to establish a methodology for the objective evaluation of alternative technologies for a specific timber harvesting situation, considering the economic, social and environmental implications. / AFRIKAANSE OPSOMMING: Grobbelaar, F.R. 2000. A methodology to aid in appropriate technology decisionmaking for developing countries. M.Sc tesis. Universiteit van Stellenbosch. Tydens die keuse van sogenaamde toepaslike tegnologie vir houtinoesting en -vervoer is ekonomie meestal die deurslaggewende faktor, hetsy verteenwoordig deur kapitaal belegging of personeelkoste. Internasionaal is daar tans In neiging na meganisasie in bosbou vir In verskeidenheid redes: bv., hoë arbeidskoste, arbeidtekort, en beroepsveiligheid. Die werklikhede van Suid-Afrika beklemtoon egter ander sake wat daadwerklike optrede vereis: nl., hoë werkloosheid, gebrek aan vaardighede, internasionale mededinging, ernstige VIGS pandemie, en In swak veiligheid-en sekuriteit rekord. Dit behoort ons aandag te fokus op die vind van plaaslike oplossings tot die probleem met die keuse van geskikte of toepaslike tegnologie ter bevordering van Suid Afrika se strewe na volhoubare ontwikkeling. Hierdie tesis poog om In metodiek te ontwikkel vir die objektiewe beoordeling van alternatiewe tegnologieë vir houtinoesting binne bepaalde omstandighede, met inagneming van ekonomiese, sosiale en omgewings implikasies.
30

Early Childhood Teacher Perspectives of Developmentally Appropriate use of Computer Applications

White, Heather S. 01 January 2015 (has links)
There is little evidence in the literature that early childhood (EC) teachers are using developmentally appropriate practices (DAP) in implementing computer applications in their classrooms. The purpose of this study was to identify EC teachers' perspectives about the use of developmentally appropriate computer applications and to identify their perspectives on strategies for implementing change toward greater use of developmentally appropriate computer applications. The study was based upon Joseph and Reigeluth's conceptual framework of systemic change processes, which provides educators with the foundation to achieve sustainable changes. The research questions that guided this qualitative case study were designed to obtain teachers' perspectives about the use of DAP while embedding technology into EC classrooms and strategies that might be used in encouraging use of DAP computer applications. Data collection included semistructured interviews with 10 EC teachers in one school and reviews of relevant documents. Data from interviews and document reviews indicated a perceived need for more integration of developmentally appropriate computer technology in the classroom and for increasing teachers' knowledge of DAP through training and staff development. Recommendations for schools included finding more and varied technology funding sources, placing greater school emphasis on the importance of a learning organization, and increasing stakeholder involvement. For teachers, recommendations were to develop additional instructional strategies for embedding DAP technology into the classroom. This study has the potential to help stakeholders and EC teachers enhance the fidelity of instruction and students' learning in the classroom.

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