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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.
11

Solubility Modeling of Athabasca Vacuum Residue

Zargarzadeh, Maryam Unknown Date
No description available.
12

Decanting and Social Sustainability: Kenya Slum Upgrading Programme (A Case Study)

Ogundele, Anthonia January 2014 (has links)
By the year 2030, over half of the global population will reside in cities. The impacts of this trend are most notable among nations within the global south, which are experiencing rapid urbanization, due to forced displacement, political, economic and environmental conditions. The infrastructure deficit, caused by rapid urbanization, experienced by most nations in the global south has created slum conditions for many of their urban residents. All levels of government including international diplomatic bodies have encouraged urban renewal programs that seek to resolve the “slum issue” in the global south. These urban renewal programs have been the subject of much criticism given the methods of redevelopment. The focus on improving the physical environment of slum dwellers and the limited attention to the resulting social consequences of such programs. The Kenya Slum Upgrading Program is a case study by which the method of redevelopment included the use of a decanting site which facilitated the temporary displacement of residents of the Kibera slum, Soweto East Village to a pre-constructed high-rise estate, until the redevelopment of the Soweto East Village is complete. Using Stren and Polèse’s concept of Social sustainability as a framework, this research seeks to understand the impacts of the use of a decanting site on the targeted community. The decanting site offered a space to understand a community in transition and critically understand the impacts of this method. The research found that social sustainability was impacted both positively and negatively within the decanting site. In fact, decanting sites are an opportunity to build social sustainability for a displaced community, instead of seeking to sustain its previous manifestation in Soweto East. The research also found that the driver for this program were international benchmarks, which may have impeded the ability for all stakeholders, at all levels, to consider the impacts of social sustainability. As we move into a global post- 2015 development framework these findings must be understood as a starting point to understanding the impacts of methods used to support large scale redevelopment programs.
13

Solubility Modeling of Athabasca Vacuum Residue

Zargarzadeh, Maryam 11 1900 (has links)
The solubility parameters for ten fractions of Athabasca vacuum residue were calculated from molecular representations via group additivity methods. Two methods were used; Marrero-Gani and Fedors. The calculated parameters were compared between the fractions for consistency, and also compared with other literature sources. The results from the Marrero-Gani method were satisfactory in that the values were in the expected range and the results were consistent from fraction to fraction. The final stage of the work on group additivities was to estimate the solubility parameter values at the extraction temperature of 473 K, and then compare the solutes to the solvents. The solubility parameters of the solvents were calculated from correlations and from the molecular dynamic simulation; the latter method did not result in fulfilling values. The most reasonable solvent and solute solubility parameters were used to assess the utility of the solubility models to explain the trends. The solubility models were not suitable for these types of materials. Stability of heavy oil fractions undergoing mild thermal reactions were predicted computationally for limited sample cracked molecules.
14

Integrated processing for heavy crude oil

Lopez, Yadira January 2015 (has links)
Energy based on non-renewable resources such as gas, oil, coal and nuclear fission, even with their serious problems of pollution, contributes to 86% of the global energy consumption. Oil will remain the dominant transport fuel: about 87% of transport fuel in 2030 will still be petroleum-based. Discoveries of conventional sources of light easy-to-access crude oil are becoming less common and current oil production levels are struggling to match demand, it is necessary to develop new non-conventional sources of oil in order to supplement conventional oil supply, whose demand is increasing continuously. A possible clue to solve this situation could be to take advantage of the extensive reserves of heavy crude oils existing in different places around the world, which could be an excellent source of more valuable hydrocarbons. In this context, some facilities called upgraders are used to process theses heavy crude oils to both increase the hydrogen-carbon ratio and improve their quality, reducing their density and decreasing their viscosity, sulphur, nitrogen and metals. The main objective in this work is to study the heavy crude oil upgrading processes in order to identify new operation schemes which explore different opportunities of integration between the upgraders and other processes or new schemes for upgraders that can sustain on its own through the production of a wide range of products. Each design alternative has been modelled with state-of-the-art commercial software packages. The crude oil dilution process was evaluated using naphtha and a light crude oil as diluents. Sensitivity analyses were done with the purpose of selecting the type and flow rate of diluent. Once the best diluent was selected, the integration of an upgrader to a refinery was studied. Heavy ends from both the upgrader and the refinery were taken as feedstocks to an integrated gasification combined cycle (IGCC). The best operation schemes for IGCC, in order to achieve the requirements of power and hydrogen for the upgrader and the refinery was determined. Different schemes for heavy crude oil processing to produce transportation fuel instead of syncrude were proposed, too. Finally, economic evaluation of all the schemes was performed to find the best solution for heavy crude oils. The best results for the dilution process of heavy crude oils were obtained when naphtha was used as diluent. The configuration proposed for the upgrader allows producing a synthetic crude oil with 35.5 °API. The integration of the upgrader to a refinery allows the treatment of the heavy streams of the refinery and transforms them into products of higher qualities. The integration of the IGCC to the upgrader and the refinery permits a complete elimination of the heavy residues produced in these units and produces hydrogen and power to be used in the site or to export. Economic evaluation shows that all the proposed processing schemes studied are economically attractive. The proposed processing schemes chosen include the integration between upgrader refinery and IGCC unit with CCS.
15

Increasing competitive advantage through upgrading : the automotive component manufacturing industry in South Africa

Grota, Paul 03 April 2011 (has links)
The research project investigates whether automotive component manufacturers located in South Africa are taking advantage of their participation in global value chains to functionally upgrade. Two factors, namely position in the value chain and global connectedness are assessed in terms of their effect on the propensity for firms to innovate and upgrade. Continuous pressure from value chain leaders to reduce costs coupled with increasing competition from other low-cost, developing economies means that South African automotive component manufacturers have to upgrade to improve their competitiveness and maintain their positions in the global value chain. This quantitative study analysed data collected through interviews from 76 companies in the National Association of Automotive Component and Allied Manufacturer‟s database of firms. The results support previous literature and demonstrate that indigenous innovation does occur under certain conditions. Whilst participation in global value chains seems to stimulate innovation, it does not necessarily guarantee that innovation will occur nor does it mean that innovation will automatically result in upgrading. Questions that require further investigation include among others the upgrading trajectory firms over time and a deeper understanding of the mechanisms used by innovation leaders to absorb and deploy the knowledge and technology obtained from global interactions. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted
16

Post Production Heavy Oil Operations: A Case for Partial Upgrading

Lokhandwala, Taher 14 March 2013 (has links)
The transportation of heavy oil is a pressing problem. Various methods have been devised to mitigate the reluctance to flow of these highly dense and viscous oils. This study is focused on evaluating a case for post-production partial upgrading of heavy oil. Specifically, we analyze the impact of visbreaking, a mild thermal cracking method, on the economic and energy demands of the post-production process. Using conservative modeling techniques and principles we find significant cost and energy savings can potentially result out of visbreaking. Cost savings result as a consequence of reduced diluent usage. Even the most conservative modeling scenario under consideration exhibits significant cost savings in the form of reduced diluent usage; these savings not only offset operational costs but provide short payback periods on capital expenditures. Additionally, the lower gravity blend resulting from visbreaking can also bring about energy and cost savings in pipeline transportation and positively impact the heavy oil value chain from the producer to a refinery or regional upgrading facility. From this basic analysis of the potential of visbreaking, we can recommend investing resources to study its viability in the field. Using this analysis as a tipping off point and with a detailed look at the chemistry of the oil in question it is possible to make a very viable case for visbreaking. In a similar vein, this analysis can serve as a guide in making a case for other partial upgrading methods as well.
17

Průmyslový upgrading a regionální rozvoj: Český automobilový průmysl / Industrial upgrading and regional development - Czech automotive industry

Ženka, Jan January 2011 (has links)
Disertační práce vychází z perspektivity globálních hodnotových řetězců a globálních produkčních sítí, které poskytují vhodný konceptuální rámec pro analýzu pravděpodobnosti delokalizace a intenzity průmyslového upgradingu. Průmyslový upgrading je považován za nezbytnou podmínku udržení konkurenceschopnosti vyspělých zemí, které čelí růstu cen výrobních faktorů. V první části práce se autor zabývá otázkou, které obory zpracovatelského průmyslu Česka jsou nejvíce ohroženy přesunem výroby do zahraničí a zda dochází ke koncentraci mezinárodně mobilních, nákladově orientovaných investic v zaostávajících regionech s vysokou mírou nezaměstnanosti a dostupnými investičními pobídkami. V druhé části byla pro období 1998-2006 měřena intenzita upgradingu široce vymezeného automobilového průmyslu Česka, jakožto nosného oboru české ekonomiky. Cílem bylo zjistit, zda byly firmy v automobilovém průmyslu Česka schopny inovovat a modernizovat své výrobní kapacity pro udržení konkurenceschopnosti navzdory rostoucím nákladům i poklesu poptávky v krizovém období 2008-2009. Vzhledem k nadměrné orientaci české ekonomiky na automobilový průmysl byly očekávány významné dopady na vývoj regionálního vzorce nezaměstnanosti. Pro tyto účely byly vytvořeny dvě unikátní databáze mikrodat, založených na ročních podnikových...
18

Essays in Firm Responses to Demand and Competition Shocks

Medina Quispe, Pamela Milagros January 2016 (has links)
<p>The aim of this dissertation is to examine, model and estimate firm responses to</p><p>demand shocks by focusing on specific industries where demand shocks are well</p><p>identified. Combining reduced-form evidence and structural analysis, this dissertation</p><p>extends the economic literature by focusing on within-firm responses of firms</p><p>to two important demand shocks that are identifiable in empirical settings. First,</p><p>I focus on how firms respond to a decrease in effective demand due to competition</p><p>shocks coming from globalization. By considering China's accession to the World</p><p>Trade Organization in 2001 and its impact on the apparel industry, the aim of these</p><p>chapters is to answer how firms react to the increase in Chinese import competition,</p><p>what is the mechanism behind these responses, and how important they are in explaining</p><p>the survival of the Peruvian apparel industry. Second, I study how suppliers'</p><p>survival probability relates to the sudden disruption of their main customer-supplier</p><p>relationships with downstream manufacturers, conditional on suppliers' own idiosyncratic</p><p>characteristics such as physical productivity.</p> / Dissertation
19

Arquitetos militantes em urbanização de favelas: uma exploração a partir de casos de São Paulo e do Rio de Janeiro / Militant architects in urbanization of favelas: an exploration from the cases of São Paulo and Rio de Janeiro

Ferreira, Lara Isa Costa 09 May 2017 (has links)
O foco desta pesquisa é a atuação de arquitetos e urbanistas militantes em urbanização de favelas. Para tal recorremos acasos concretos de experiências de urbanização de favelas com a participação destes técnicos na Região Metropolitana de São Paulo e Município do Rio de Janeiro da década de 60 aos anos 2010. Pretendemos desta forma olhar para este campo de atuação do arquiteto e urbanista, mas focando naqueles que historicamente têm exercitado intervenções mais justas, mais integradoras, mais emancipadas em favelas. Trata-se de um reconhecimento da atuação destes arquitetos - sujeitos políticos, mas também a apresentação de uma retrospectiva sobre as suas práticas, muitas vezes pioneiras no seu campo de atuação. Trata-se também de uma reflexão sobre os alcances e limites da sua ação militante. Selecionamos sujeitos que se destacam nessa atuação e cujas experiências que acontecem num tensionamento entre técnica, estética e ética. Na prática, os resultados são por vezes limitados, e muitas vezes frustrantes, mas ao mesmo tempo, seguramente inspiradores. A partir dos seus relatos e reflexões, mesmo que em contexto muito diversificados, encontramos pontos de contato nas metodologias, nas ações e nas intenções e que denominamos como práticas militantes em urbanização de favelas. Com esta pesquisa propomos um mapeamento de possíveis referências, mas também o questionamento sobre o lugar do arquiteto frente a territórios de conflito. / This research focus on the action of militant architects and urban planners in what regards slum upgrading processes in favelas from the 60\'s to the 10\'s decades. In order to do so, we resort to concrete cases of slum upgrading experiences in favelas that counted upon the participation of theses subjects in the metropolitan region of São Paulo, as well as in the municipality of Rio de Janeiro. We aimed at regarding this field of action of architects and urban planners focusing on the professionals that have been proposing interventions that seek to be more just, more integrated, and more emancipated in favelas. This work intends to recognize the background of these architects - understood as political subjects herein - but also, to approach a retrospective about their experiences that usually reveal to be pionneer in their professional field. It also aims at analyising the limits and advances of their militant action. We have chosen professionals that stand out in their field of action, and whose experiences stress the boundaries of ethics, aesthetics and techinique. In the end, the results of their experiences are rare, generally frustrating, but at the same time, surely inspiring. We have built our analysis upon their oral information and their own relfections over their experience, and, despite the different contexts, we have come to common points in terms of methods, practice and inteverntions, that we have have designated as militant practices in slum upgranding. Through this research, we present a mapping of possible references, but also a questioning over the role of architects in territories of conflicts.
20

Upgrading e inserção nas Global Value Chains: o caso do Cluster vitivinícola do submédio do Vale do São Francisco na ótica dos novos produtores mundiais

CRISÓSTOMO, Antonio Pires 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T17:37:36Z (GMT). No. of bitstreams: 2 arquivo7686_1.pdf: 2140925 bytes, checksum: 3a2b53d19640a7de63957ed5c3817353 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nos últimos 25 anos, a vitivinicultura mundial tem passado por grandes transformações, por meio das quais velhos produtores têm perdido espaço para os novos . Entre os fatores que contribuíram para essa mudança estão a adoção de práticas de P&D e a habilidade desses novos produtores em utilizar os conceitos de marketing e de marca. Estudiosos sobre competitividade enfatizam que a forma mais segura para as empresas, principalmente as dos países em desenvolvimento, inserirem-se nas global value chains (GVC) é por meio da formação de clusters, que nesses países são caracterizados por pequenas e médias empresas e intensa colaboração entre elas, com apoio institucional. Tal situação é favorável à realização de upgradings, essenciais para atender aos exigentes compradores globais, muito influentes nos clusters. Este estudo se dedica à análise de várias pesquisas sobre duas novas regiões produtoras de vinho em âmbito mundial África do Sul e Chile , usando-a para comparar e propor condições que possibilitem a realização de upgradings e a inserção do cluster vitivinícola do Submédio do Vale do São Francisco nas GVC. Para isso, no primeiro momento, realizou-se o levantamento bibliográfico e efetuou-se a participação em vários workshops internacionais sobre cadeias globais e upgradings. Posteriormente, foi realizada a pesquisa de campo, incluindo entrevistas com diretores, enólogos e agrônomos de todas as empresas produtoras de vinho da região do Vale do São Francisco, entre outros especialistas. A região do Submédio do Vale do São Francisco se caracteriza por constante aumento na produção de vinhos finos, apesar de o panorama vitivinícola nacional apresentar tendência contrária: redução na produção desses vinhos e aumento na produção dos vinhos comuns. Conclui-se que essa região tem apresentado algumas características similares às das outras duas analisadas, mais rapidez na produção de vinhos finos de qualidade e início de inserção nas cadeias de valor global, necessitando, contudo, de alguns ajustes que facilitem a competitividade. De uma forma geral, muitos problemas afetam a competitividade da vitivinicultura no Brasil. Para a região do Submédio do Vale do São Francisco, este estudo propõe estratégias que podem facilitar a realização de upgradings e a inserção do seu vinho nas GVC. As mudanças sugeridas são classificadas em três níveis: da empresa, do cluster e do Estado

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