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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.
51

Urban Transformation in China: From an Urban Ecological Perspective

Han, Ruibo 13 September 2012 (has links)
China has undergone significant urban growth and industrialization over the last 30 years and its incredible development continues to move ahead at an increasingly rapid pace. In terms of urban expansion, China has just recently surpassed the world’s average urbanization rate of 50%, as it moves its massive population from rural to urban areas at an astonishing speed. It’s massive population and fast urbanizing speed aside, China is also unique in terms of its socio-political system and historical-cultural context: it is a hybrid of government planning and market forces. Since it encompasses a large part of the global population and has had a vastly different urbanization experience than that of Western countries, around which most theories are based, studying China’s urbanization is an opportunity to contribute to the field of urban studies in an unprecedented manner. However, these differences also make it difficult to develop a comprehensive study of China’s urban system since the predominant theories in the field are best suited to Western cities. This research rises to this challenge by systematically studying the relationship between the socioeconomic and biophysical processes in the Chinese urban system to understand the interaction between human and physical factors, and the landscape patterns that result from these interactions. This complex urban system is examined using a hierarchical, top-down approach. At the highest level is a Macro-scale analysis of the national urban system, followed by a study of the regional urban system: the JingJinJi Metropolitan Area at the Meso-scale, and finally a Micro-scale examination with a focus on the city of Beijing. Since urban systems develop over both time and space, the urban system is analyzed spatio-temporally on all three levels. Research at the national scale is composed of two parts. First, the challenges and opportunities of China’s urban development since the foundation of the People’s Republic of China in 1949 are investigated in a general context. The institutional barriers that impede the management and continuation of China’s urban development are also discussed. Rank-size Analysis and satellite images are used to present the structural transitions of city scaling and urban clusters. These changes come with a series of challenges that are also iterated and discussed. This is followed by an analysis of the spatial distribution and transition patterns of China’s urban system using Centrographic Analysis, particularly since the post-1979 reforms. Second, the Macro-scale research focuses on a study of the urban hierarchy that is based on inter-city interactions as determined by the Synthesized Gravity Model (SGM). Under this model socioeconomic variables are synthesized and represented by the Influential Factor, while the Function Distance is derived from a Network Analysis that is based on multiple transportation methods. As an improvement on the conventional Gravity Model (GM), the SGM is used to accurately establish and represent the nodal structure of China’s urban system, the evolution of its hierarchical structure, and the relationships that exist between the nodal structure and socioeconomic factors. The results based on the SGM indicate that China’s national urban system is characterized by the emergence of urban clusters with stronger inter-city interactions since the 1990s. However, development among cities within certain urban clusters is not even, although the general pattern indicates a lessening inequality among cities. Spatially, while most cities at the top of the hierarchy are located in the east of China, cities in the middle and west of the country are also gaining higher positions in the hierarchy over time. On the Meso-scale, the applicability of the Cellular Automata (CA)-based SLEUTH model for regional urban growth pattern is studied through a focus on the JingJinJi Metropolitan Area (Beijing-Tianjin-Hebei). By integrating socioeconomic factors into a modified SLEUTH model, the urban growth dynamics and future development scenarios of the area are simulated and predicted. The results based on the CA model show that this region is characterized by a dynamic development pattern with high spreading and breeding growth rules that relies greatly on the growing transportation systems. It also allows for the projection of three possible future urban growth scenarios, each occurring under different environmental and development conditions, showing the future urban growth with or without further intervention. This research confirms that four factors play essential roles in the formulation of the urban growth mechanism of the JingJinJi Metropolitan Area: Urban policies, Industry restructuring, Rural-urban migration, and Reclassification of urban boundaries. The Micro-scale study of Beijing is conducted from two perspectives: the social and natural. The social aspect adopts the factorial ecology approach to identify the social landscape patterns and the factors that have shaped Beijing’s social space in 1990 and 2000. The social mosaic has experienced a significant change due to suburbanization, resulting in a more dynamic and complex internal structure since the 2000s. From a natural perspective, Beijing’s physical landscape patterns are extracted by processing remotely sensed images that have the same temporal span. The physical change through landscape metrics demonstrates that Beijing’s expansion has generated a more complex and fragmented land use/cover pattern. Meanwhile, transportation systems play a significant role in urban expansion, although the expansion across the space (zonal rings and directional sectors) is not even. Finally, the relationship between the social and physical landscapes is quantitatively defined by the Geographically Weighted Regression (GWR) technique, using physical landscape metrics as dependent variables and social areas as independent variables. The GWR is able to demonstrate the relationship between the social and physical landscapes at this level: as a city’s social mosaic becomes more varied over time it results in the fragmentation of that city’s physical space.
52

Gravity anomalies, flexure, and the long-term rigidity of the continental lithosphere

Jordan, Tom A. R. M. January 2007 (has links)
The cause and distribution of spatial variations in the mechanical properties of the continental lithosphere are fundamental questions for modern geology. In this study variations in long-term lithospheric rigidity have been investigated. These investigations used profile- and grid-based flexural models of the lithosphere’s response to geologically imposed topographic, or buried, loads. These models were constrained by topographic and gravity data allowing recovery of best fitting rigidity values. In Oman a Cretaceous ophiolite acts as a significant load on the continental crust. Flexural models along profiles orthogonal to the ophiolite strike show that the observed gravity data can be best modelled by an elastic beam with standard thickness (T<sub>e</sub>) of 30 km. Along strike there is shown to be significant variation in the foreland shape and the observed gravity signal. This, it is proposed, relates to the complex tectonic processes which occurred as the ophiolite was obducted. The Himalayan foreland has been the focus of controversy over the recovered long-term rigidity of the continents, with recovered T<sub>e</sub> values ranging from 40 to over 90 km. Both profile- and grid-based techniques show that T<sub>e</sub> is high (>70 km) in the foreland region. Across the India-Eurasia collisional system as a whole T<sub>e</sub> values are variable. Beneath the Tibetan plateau recovered values are generally low (<10 km), while the plateau margins are marked by regions of higher rigidity. Recovered T<sub>e</sub> values across the Arabia-Eurasia collisional system range from over 60 km in the foreland region to close to zero beneath the high Zagros mountains. In the eastern part of the foreland, flexural models match the gravity data; however, they disagree with sediment thickness data for the material infilling the foreland. This discrepancy is interpreted in terms of de-coupling of the flexural lithosphere from the shallower crustal levels, caused by the presence of significant salt deposits in this region. Application of grid-based techniques to South America, North America and Europe recover a broad range of Te values from ∼0 to over 90 km. The low T<sub>e</sub> values are explained in active orogenic belts in terms of current processes acting to weaken the lithosphere, and in the continental interiors as the relics of past orogenic events. High T<sub>e</sub> values in the continental interiors correlate with ancient cratonic cores which have undergone little deformation since their formation in the Archean. This study shows that T<sub>e</sub> variations have a critical influence on the development of large compressional orogenic belts. In the Himalayan and Andean orogens there is a correlation between the over-thrusting of the orogenic belt and high T<sub>e</sub> foreland regions. Where lower T<sub>e</sub> regions are seen, less over thrusting is apparent, and in the case of the India-Eurasia collisional system out-flow of lower crustal material may be occurring.
53

Les choix stratégiques des firmes multinationales et la relation entre les exportations et les IDE : application d’un modèle Probit bi-varié, et d’un modèle de gravité dynamique aux pays Méditerranéens / The strategic choice of the multinational firms and the relationship between exports and FDI : application of bivariate probit model, and dynamic gravity model in the Mediterranean area

Sabra, Mahmoud 07 July 2011 (has links)
Dans cette thèse, nous discutons la relation entre les exportations et l’IDE, et tentons de trouver une relation de long terme entre ces variables. Dans cette analyse, nous étudierons tout d’abord de manière empirique les déterminants des exportations et des l’IDE, à la fois au niveau micro et macro. Ceci nous permettra par la suite de détecter plus précisément la relation entre ces deux variables. Plus précisément, cette thèse comporte les points suivant : Au niveau micro (niveau de la firme), les multinationales sont susceptibles de mettre en œuvre les deux activités (exportations et IDE) pour servir les marchés étrangers, mais les choix stratégiques des multinationales permettent aussi de choisir entre exportations et IDE. Sur ce point, la productivité des entreprises multinationales ainsi que leurs autres caractéristiques ont un rôle crucial pour éclairer le mécanisme de choix entre les stratégies et la relation entre exportations et investissements. Ceci fera l’objet de la première partie qui proposera une application au cas français. Dans cette partie, nous distinguerons également les décisions stratégiques en fonction de la taille de l’entreprise (très grandes ou grandes entreprises françaises). Au niveau macro, nous chercherons à identifier les déterminants simultanés des exportations et des IDE. Pour se faire, un système gravitaire dynamique bivarié sera estimé afin d’éclairer le rôle de ces déterminants et la relation entre exportations et IDE. Ceci fera l’objet de la seconde partie, qui sera appliquée aux échanges entre la France et dix partenaires euro-méditerranéens. Le choix de ces pays s’appuie sur l’importance qu’ils revêtent dans les échanges français. Par ailleurs, l’absence de littérature appliquée à ces pays dans ce domaine constitue une motivation supplémentaire. / In this thesis, we discuss the relationship between exports and FDI, and we aim to find a long-term relationship between these variables. In the course of the thesis analysis, we study empirically the exports and FDI determinants, at macro and micro analysis. This allows us to detect precisely the relationship between the both variables. In other words, this thesis carry out the following points: at micro level (company level), the multinationals are likely to implement the two activities (exports and FDI) to serve the foreign market, but the multinationals strategic choice can also choose between exports and FDI. On this point, the productivity of the multinational corporations and their other characteristics have a crucial role to clarify the mechanism of the choice between strategies and the relationship between exports and FDI. In fact, this is the first empirical part, which is the first similar application on the French companies. In the part, we also distinguish between strategic decisions based on company on the company size (large, very large and both groups of French enterprises).At the macro level, we will seek to identify the simultaneous determinants of exports and FDI. To do so, a gravity system is estimated bivariate dynamic equations to illuminate the role of these determinants and the relationship between exports and FDI. This is the second empirical part, which is applied on the capital and goods exchange between France and ten Mediterranean partners. The choice of these countries based on their importance in French trade. Moreover, the lack of the literature applied to these countries in this area is extra motivation.
54

On the Determinants of Global Bilateral Migration Flows

Crespo Cuaresma, Jesus, Moser, Mathias, Raggl, Anna 06 1900 (has links) (PDF)
We present a method aimed at estimating global bilateral migration flows and assessing their determinants. We employ that fact that available net migration figures for a country are (nonlinear) aggregates of migration flows from and to all other countries of the world in order to construct a statistical model that links the determinants of (unobserved) migration ows to total net migration. Using simple specifications based on the gravity model for international migration, we find that migration flows can be explained by standard gravity model variables such as GDP differences, distance or bilateral population. The usefulness of such models is exemplified by combining estimated specifications with population and GDP projections in order to assess quantitatively the expected changes in migration flows to Europe in the coming decades. / Series: WWWforEurope
55

Les mutations géographiques et technologiques de l’industrie automobile : une analyse par l’approche gravitationnelle / Geographical and technological mutations of the automotive industry : an analysis by gravitational approach

Abi Zeid, Antoine 04 June 2018 (has links)
Les pays émergents dotés d’un marché dynamique sont devenus l’« espace » principal de la production automobile. Les pays développés restent les principaux exportateurs. Dans cette thèse nous mesurons la valeur des exportations théoriques des pays émergents par rapport aux paramètres (PIB, coûts d’échange) d’un modèle de gravité augmenté. Les exportations de voitures de la plupart des pays émergents risquent de stagner à cause de la faible économie de la connaissance et des coûts élevés d’échange dans ces pays. L’Iran a une opportunité pour augmenter ses exportations automobiles en améliorant la qualité de ses produits domestiques ou en construisant des plateformes exportatrices pour les FMN. Les exportations de la Turquie et du Mexique risquent de stagner à moins que le Mexique augmente ses exportations vers l’Europe et l’Asie, et que la Turquie améliore la valeur ajoutée de son industrie. Le véhicule électrique et la batterie lithium-ion incarnent l’avenir de l’industrie automobile. Il est prévu que la Chine et les États-Unis soient les principaux exportateurs de la batterie li-ion. Il est fort probable que les exportations américaines augmentent surtout vers les pays les plus avancés en matière des technologies de l’information et de la communication. / Emerging countries (EC) endowed with dynamic markets became the main automotive production area. Developed countries are still the main exporters. In this thesis, we measure the theoretical value of exports of EC based on the parameters (GDP, trade costs) of an augmented gravity model. The car exports of the majority of EC risk stagnation because of weak knowledge economy & high trade costs in these countries. Iran has an opportunity to increase its automotive exports under the condition of improving its domestic products and/or building export-platforms for global automakers. The exports of Turkey & Mexico risk stagnation unless Mexico increases its exports to Europe & Asia, and Turkey increases the added-value of its industry. Electric vehicles and lithium-ion batteries are the future of the automotive industry. China & the USA are expected to be the main exporters in the field of li-ion batteries. The growth of American batteries exports is highly probable notably to countries with advanced ICT infrastructure.
56

International and domestic Migration Patterns : International immigration effect on internal out-migration patterns in the German states between 1993 and 2016

Frey, Reik January 1994 (has links)
Internal migration has frequently been subject of empirical research. This study attempts to find a relationship between international immigration and internal out-migration in all German states, covering the time period between 1993 and 2016. The underlying theories were established by Card et al. (2008), Schlömer (2012), Florida (2002) and Chiswick and Miller (2015). These were used to develop a modified version of the gravity model. The dataset was received from the Federal Statistical Office of Germany (Statistisches Bundesamt). The regressions were executed using a fixed effects model and a pooled OLS as a robustness check. The empirical findings suggest no evidence of a statistically significant effect of international immigration on internal out-migration patterns in the covered period. Control variables suggest policymakers to focus on other factors when the effects of immigration policies on internal out-migration are being considered.
57

Determinantes do investimento estrangeiro direto bilateral: uma abordagem do ambiente de negócios / Determinants of bilateral direct foreign investment: a business environment approach

Weeks, Daniel Valladares 23 April 2014 (has links)
O investimento estrangeiro direto - IED é um dos principais fluxos de capitais internacionais, sendo um fator importante para o balanço de pagamentos, além de ser considerado também um condutor de transferências tecnológicas entre países e indutor de desenvolvimento econômico. O estudo dos determinantes deste tipo de investimento transnacional, apesar de relativamente recente, tem ganhado relevância no debate econômico. Através da abordagem do modelo gravitacional, este trabalho explora diversas metodologias econométricas para a estimação desse modelo. O método Poisson Pseudo-Maximum-Likelihood - PPML mostrou estatísticas mais robustas para as estimações, indo de encontro com a literatura econômica que o elege como o método mais adequado para as características dos dados utilizados na investigação do problema em questão. Os resultados obtidos mostraram que, além das variáveis usualmente utilizados na abordagem clássica do modelo gravitacional, como tamanho do PIB e distância, os fatores ligados ao ambiente de negócios também são significantes em explicar a determinação do IED bilateral. Desta maneira, a aplicação de reformas e medidas com o objetivo de melhorar o ambiente de negócios é desejável para a aumentar a atratividade de recursos nesta modalidade de investimento. / The foreign direct investment - FDI is one of the main international capital flows, being considered an important component of the balance of payments and also a driver of technological transfers between countries and promoter of economic development. The study of that kind of transnational investment, although relatively recent, has gained importance in the economic debate. This work explores many econometric methodologies in a gravity model approach. The Poisson Pseudo-Maximum-Likelihood method - PPML showed more robust results to the estimations, as appointed by the economic literature. The results obtained showed that, beyond the usual variables used in the gravity models, such as GDP size and distance, variables connected to the business environment are significant to explain the determination of bilateral FDI. Therefore, reforms and measures aimed to improve the business environment are desirable for increasing the attractiveness of that kind of international investment.
58

Integração regional e desenvolvimento: o caso da Comunidade Econômica dos Estados da África Ocidental (CEDEAO) / Regional Integration and development: the case of economic community of West African States-(ECOWAS)

Santos, Celso Medina 14 April 2014 (has links)
Esta dissertação foi realizada como requisito parcial para aquisição do título de mestre em Relações Internacionais pelo Instituto de relações Internacionais da Universidade de São Paulo (IRI-USP). Ela compreende dois artigos diferentes. No primeiro, discute-se a teoria da integração regional a partir de abordagens da Ciência Política e da Economia Internacional. Para tanto, desenvolve um estudo de caso a respeito do processo de integração regional na África, qual seja, compreender os resultados no domínio da cooperação econômica a respeito do CEDEAO (Comunidade Econômica dos Estados da África Ocidental). O argumento principal do artigo é o de que o processo pode ser lido de acordo com a perspetiva neofuncionalista da integração regional. No segundo artigo avalia-se o efeito da criação da CEDEAO através do modelo Gravitacional. Trabalha-se com dados em painel e corrige-se o viés de seleção para estimar o efeito do acordo regional em termos de criação e desvio de comércio. Os resultados indicam que a CEDEAO nem promoveu a criação de comércio intra-bloco e nem produziu o efeito de desviar o comércio internacional com terceiros países de fora do bloco, em benefício dos membros. / This research was conducted as partial requirement for the achievement of the master\'s degree in International Relations at the Institute of International Relations, University of São Paulo (IRI-USP). It comprises two separate articles. First, given the economic objective of the initial motivation for the establishment of ECOWAS, we question why the ill=observed results were not an impediment to the pursuit of the integration. The interpretative insights were derived from historical and political context in dialogue with the neo-functionalist theory of regional integration. The article`s main argument is that the challenge of sub-regional security led to the outgrow of political objectives. Understanding that there is a new convergence of interests, the bloc undergoes constant pursuit of a consistent institutional matrix including the objectives which were added, and in the other hand, reflects the degree of involvement of the various national groups that determine the external behavior of each member country. In the second paper, we attempt to evaluate the effect of the instruments of the trade policy on welfare in ECOWAS applying a Gravitational Model. Using panel data and correcting for selection bias, we estimate the effect of the agreement in terms of trade creation and trade diversion. Results show that ECOWAS did not diverted trade, but had a small effect on intra block trade. The variable that captures the effect of trade creation is not statistically significant.
59

Requisitos ambientais no mercado de soja brasileiro: descrição e avaliação de impacto / Environmental requirements in the Brazilian soybean market: description and impact assessment

Soares, Aline Fernanda 19 December 2016 (has links)
A soja vem se destacando como proteína vegetal e seu consumo deve aumentar nos próximos anos, acompanhando a tendência geral de demanda crescente por alimento. No entanto, o aumento da oferta de soja, assim como de outros produtos agrícolas, pode gerar impacto negativo para o meio ambiente, o que levanta uma série de preocupações sobre este setor, exigindo resposta dos agentes da cadeia produtiva de soja para que essas preocupações não se tornem restrições de demanda e altere os padrões de comércio. Este estudo foi estruturado em formato de artigos científicos, trazendo, no primeiro deles, uma análise qualitativa e crítica das iniciativas do setor sojicultor para atender aos novos paradigmas relacionados aos requisitos ambientais, e, particularmente, aqueles impostos pelo mercado internacional. O conjunto de iniciativas realizadas pelo governo brasileiro, quer seja pelos agentes da cadeia, governo ou organizações não-governamentais, tende a se complementar, contribuindo para uma proteção mais efetiva do meio ambiente. A Moratória da Soja não conseguiu diminuir a ocupação da soja em áreas desflorestadas dos estados do Mato Grosso, Pará e Rondônia, situados no bioma Amazônia; mas o avanço foi muito pequeno, principalmente quando comparado ao que ocorreu nas áreas em que a Moratória não incide, como é o caso do cerrado mato-grossense e de MATOPIBA. O programa Soja Plus, além de preencher a lacuna do governo brasileiro em extensão rural, abrange elementos tão relevantes quanto a conversão de vegetação, como o uso responsável de herbicidas. O segundo artigo apresenta uma análise empírica, visando quantificar o impacto dos requisitos ambientais nas exportações do complexo soja. Os resultados da equação gravitacional, estimada para o período de 1993 a 2014, tendo como variável dependente as exportações de soja em grão, farelo e óleo de soja dos três maiores exportadores do complexo soja, Brasil, Estados Unidos e Argentina, indicam que a queda na razão de decoupling, variável proxy do meio ambiente, impacta positivamente as exportações do complexo soja. Isto comprova a tese de Porter e Linde de que é possível produzir de forma ambientalmente correta e aumentar a competitividade no mercado internacional. / Soy has gained highlight as vegetable protein and its consumption should increase in the coming years, following the general trend of increasing demand for food. However, the increase in soybean supply, as well as other agricultural products, can have a negative impact on the environment, which raises a number of concerns about this sector, requiring response of the soy productive chain to these concerns do not become demand restrictions and change trade patterns. This study was structured in scientific articles format, bringing, in the first of them, a qualitative and critical analysis of soybean industry initiatives to meet the new paradigms that emerge related to environmental requirements and, particularly, those imposed by the international market. The set of initiatives undertaken whether by the Brazilian government, chain actors, government or non-governmental organizations, tends to complement and contribute to a more effective protection of the environment. Soy Moratorium failed to reduce the soybean occupation in deforested areas in the Amazon biom of Mato Grosso, Para and Rondonia states; but the increase was very small, especially when compared to what occurred in areas where the Moratorium does not apply, as is the case of Mato Grosso cerrado (savanna) and MATOPIBA. The Soja Plus program, in addition to filling the gap of the Brazilian government in rural extension, addresses relevant issues as important as vegetation conversion, such as the responsible use of herbicides. The second article presents an empirical analysis to quantify the impact of environmental requirements on the soy complex exports. The results of the gravity equation, estimated for the period from 1993 to 2014, to soybean, soymeal and soybean oil exports from the three world largest exporters, Brazil, the United States and Argentina, indicate that the drop in the decoupling ratio, a proxy for environment variable, impacts posively the soy complex exports. This reassures the Porter and Linde\'s thesis that it is possible to produce in an environmentally friendly way while increasing competitiveness in the international market.
60

Climate, Conflict and Forced Migration

Abel, Guy, Brottrager, Michael, Crespo Cuaresma, Jesus, Muttarak, Raya January 2019 (has links) (PDF)
Despite the lack of robust empirical evidence, a growing number of media reports attempt to link climate change to the ongoing violent conflicts in Syria and other parts of the world, as well as to the migration crisis in Europe. Exploiting bilateral data on asylum seeking applications for 157 countries over the period 2006-2015, we assess the determinants of refugee flows using a gravity model which accounts for endogenous selection in order to examine the causal link between climate, conflict and forced migration. Our results indicate that climatic conditions, by affecting drought severity and the likelihood of armed conflict, played a significant role as an explanatory factor for asylum seeking in the period 2011-2015. The effect of climate on conflict occurrence is particularly relevant for countries in Western Asia in the period 2010-2012 during when many countries were undergoing political transformation. This finding suggests that the impact of climate on conflict and asylum seeking flows is limited to specific time period and contexts.

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