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Modeling Of Freight Transportation On Turkish HighwaysUnal, Leyla 01 July 2009 (has links) (PDF)
Transportation planners are often faced with the problem of estimating passenger and freight flows between regions. In the literature there are many models for passenger flows. However, models about freight flows are more limited. Modeling freight flow is also more complex than modeling passenger flow and there are many agents related with freight flows. In addition, data availability is a critical factor. In this research, freight flows between provinces in Tü / rkiye are forecasted by demand analysis.
Transportation is one of the important activities of human beings and plays an important role for spatial interactions in economic growth. In other words, there is a very strong linkage between economic growth and the freight flow, thus transportation demand. Regional trade as spatial flow appears on transportation systems as freight flows.
In this study, using the existing limited data and surveys in Tü / rkiye, nationwide origin-destination (O-D) matrix of freight flows between provinces is obtained. Using this empirical matrix, the generation of freight flows of provinces is formulated depending on the socioeconomic and demographic variables by means of multiple linear regression analysis. In addition, interactions of freight flows between provinces and economic growth of regions are investigated.
The generations and attractions of provinces as freight flow are distributed between provinces with traditional gravity model. By comparing observed O-D matrix and simulated O-D matrix, gravity model is calibrated. Calibration is also performed by freight trip length distribution.
In this research, two steps of traditional &ldquo / four-step analysis&rdquo / , &ldquo / trip generation&rdquo / and &ldquo / trip distribution&rdquo / , are applied to develop nationwide freight demand model between the provinces in Tü / rkiye. The developed model is single-mode, single commodity and nationwide.
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Turkish Trade Flow and the EU : A study of a potential membershipSaid, Robert, Rivero, Adela January 2008 (has links)
<p>This bachelor thesis examines how the trade flow of Turkey would change if the country becomes a member in the EU. This is done by analysing the Turkish trade flow with the EU and ROW over the period 1995 – 2005. The main question is if trade creation and trade diversion occurs?</p><p>The model used in this paper is a gravity model influenced by Soloaga and Winters (2000) gravity model. To be able to answer the purpose of this paper we used a crosssectional regression and base our analysis on our results.</p><p>The conclusion of this paper is that Turkey’s trade flow with the EU will increase if full-membership is accomplished. This leads to trade diversion and trade creation towards the other members-states within EU. We see Turkey as the key to the door for Middle Eastern countries and the EU; this implies that if Turkey becomes a member-state in EU, the trade could increase between these two continents.</p> / <p>Denna kandidatuppsats undersöker huruvida Turkiets handelsflöde kan förändras av ett eventuellt Europeiskt medlemskap. Det är gjort genom att analysera Turkiets handelstrend under perioden 1995 – 2005. Huvudfrågan är huruvida handelsfördelning och handelsökning sker?</p><p>Modellen som används i uppsatsen är en gravitations modell influerad av Soloaga och Winters (2000) gravitations modell. För att kunna besvara syftet i uppsatsen har vi använt oss av en tvärsnittsregression och baserat analysen på resultaten.</p><p>Sammanfattningsvis ser man att Turkiets handelsflöde med EU ökar av ett eventuellt medlemskap i EU. Detta leder till handelsökning samt handelsfördelning gentemot nuvarande medlemmar. Vi anser även att Turkiet är nyckeln Mellanöstern samt EU, vilket innebär att fullt medlemskap ökar handeln mellan dessa två kontinenter.</p>
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High performance algorithms to improve the runtime computation of spacecraft trajectoriesArora, Nitin 20 September 2013 (has links)
Challenging science requirements and complex space missions are driving the need for fast and robust space trajectory design and simulation tools. The main aim of this thesis is to develop new and improved high performance algorithms and solution techniques for commonly encountered problems in astrodynamics. Five major problems are considered and their state-of-the art algorithms are systematically improved. Theoretical and methodological improvements are combined with modern computational techniques, resulting in increased algorithm robustness and faster runtime performance. The five selected problems are 1) Multiple revolution Lambert problem, 2) High-fidelity geopotential (gravity field) computation, 3) Ephemeris computation, 4) Fast and accurate sensitivity computation, and 5) High-fidelity multiple spacecraft simulation. The work being presented enjoys applications in a variety of fields like preliminary mission design, high-fidelity trajectory simulation, orbit estimation and numerical optimization. Other fields like space and environmental science to chemical and electrical engineering also stand to benefit.
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The Effects of Food Safety Standards on Trade and Welfare: The Case of EU Shrimp ImportsLi, Xiaoqian 01 January 2014 (has links)
This research explores the link between a gravity model and welfare frameworks and then applies the quantitative model system to analyze how trade and welfare is affected by the Minimum Required Performance Limits (MRPL) in the shrimp importing market of European Union.
The quantitative model system consists of two parts: first, this study uses the “phi-ness” gravity model to investigate the trade effects of MRPL on EU shrimp market. The “phi-ness” gravity model partitions the standard variables to avoid biased estimation caused by the correlation between time and country fixed effects and policy variables. The Poisson Pseudo Maximum Likelihood (PPML) method is incorporated into the estimation in order to control for the zero valued observations.
Second, based on the theoretic foundation of the gravity model, this research sets up the specific nested Constant Elasticity of Substitution (CES) model of consumers’ utility and further explores the linkage between these two models. The nested CES model incorporates the effects of MRPL on consumers’ confidence in domestic food as well as foreign food imported from developed and developing countries.
The empirical results confirm a consistent fact with previous empirical studies: stricter MRPL has significant and negative effects on trade integration between EU and trading partners with lower level of food safety standards. The welfare analysis shows that the zero tolerance policy of MRPL standard would dramatically enhance consumers’ demand for domestic shrimps and foreign shrimps imported from developed countries but reduce the quantity of shrimp supplied from developing countries. It is also indicated that the increased level of MRPL lead to an increase in welfare of domestic consumers, suppliers in developing countries, and in total international trade, as well as a decrease in the welfare of domestic suppliers and foreign suppliers from developed countries.
The empirical results also indicate that the combination of GM and Welfare Approach can also be applied to research on other standards or other industries.
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An Empirical Investigation of Optimum Currency Area Theory, Business Cycle Synchronization, and Intra-Industry TradeLi, Dan 19 December 2013 (has links)
The dissertation is mainly made up of three empirical theses on the Optimum Currency Area theory, business cycle synchronization, and intra-industry trade. The second chapter conducts an empirical test into the theory of Optimum Currency Area. I investigate the feasibility of creating a currency union in East Asia by examining the dominance and symmetry of macroeconomic shocks. Relying on a series of structural Vector Autoregressive models with long-run and block exogeneity restrictions, I identify a variety of macroeconomic disturbances in eleven East Asian economies. To examine the nature of the disturbances, I look into the forecast error variance decomposition, correlation of disturbances, size of shocks, and speed of adjustments. Based on both statistical analysis and economic comparison, it is found that two groups of economies are subject to dominant and symmetrical domestic supply shocks, and that the two groups respond quickly to moderate-sized shocks. Therefore, it is economically feasible for the two groups of economies to foster common currency zones.
The third chapter investigates the different effects of intra- and inter-industry trade on business cycle synchronization, controlling for financial market linkage and monetary policy making. The chapter is the first attempt to use intra- and inter-industry trade simultaneously in Instrument Variable estimations. The evidence in my paper is supportive that intra-industry trade increases business cycle synchronization, while inter-industry trade brings about divergence of cycles. The findings imply that country pairs with higher intra-industry trade intensity are more likely to experience synchronized business cycles and are more feasible to join a monetary union. My results also show that financial integration and monetary policy coordination provide no explanation for synchronization when industry-level trade are accounted for.
The fourth chapter extends the third chapter and explores how the characteristics of global trade network influence intra-industry trade. Borrowing the concept of structural equivalence, the similarity of two countries’ aggregate trade relations with other countries, from the social network analysis, this study incorporates this measure of trade network to the augmented gravity model of intra-industry trade. I build up two fixed effects models to analyze intra-industry trade in the raw material and final product sectors among 182 countries from 1962 through 2000. Structural equivalence promotes intra-industry trade flows in the final product sector, but it does not influence intra-industry trade in the crude material sector. Moreover, structural equivalence has been increasingly important in boosting intra-industry trade over time. / Graduate / 0508
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Obchod a politické vlivy: politické determinanty mezinárodních obchodních toků / Trade and Politics: Political Determinants of International Trade FlowsSosnovec, Jan January 2018 (has links)
Charles University in Prague Faculty of Social Sciences Institute of Economic Studies Master's thesis Trade and Politics: Political Determinants of International Trade Flows Author: Bc. Jan Sosnovec Supervisor: Ing. Vilém Semerák, M.A., Ph.D. January 3, 2018 Abstract This thesis takes a comprehensive look at the relationship between international trade and politics. The first part of this thesis is theoretical. Besides providing a useful overview of this highly complex subject, it makes a contribution to the contemporary theory by proposing two simple models. The first of these models explains how because of complementarity of institutions, countries end up stuck with inefficient institutions and consequently high trade costs; countries can break out of this inefficient equilibrium only by coordinating their actions. The second proposed model shows how governments set trade barriers in order to pursue their political aims, while at the same time staying popular in order to remain in power. This model is consistent with a wide variety of regime types and ideologies, and takes into account voter heterogeneity. The second part of this thesis is empirical. It uses the gravity model of trade, with multilateral resistance terms represented either by fixed effects or by the Baier-Bergstrand linear approximation of...
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Uma avaliação de efeitos potenciais de acordos regionais entre Brasil e União Européia para as exportações de produtos agrícolas brasileiros / An assessment of potential effects of regional agreements between Brazil and the European Union for exports of Brazilian agricultural productsDiogo Del Fiori 18 November 2015 (has links)
As relações entre a União Europeia (UE) e os seus parceiros comerciais incluem Acordos Preferenciais de Comércio (APCs) com países em desenvolvimento para produtos agrícolas e industriais, destacando-se países da África, Caraíbas e Pacífico. A política de caráter cooperativo no setor agrícola da APC-UE, possui por objetivo a preservação do ambiente, segurança alimentar, crescimento econômico e desenvolvimento sustentável. Excetuando-se esses Acordos Preferenciais, a União Europeia possui no setor agrícola um dos segmentos de maior proteção comercial. Trata-se do principal mercado para os produtos agrícolas brasileiros. No entanto, esse setor, no Brasil, poderia obter melhor desempenho caso a UE não praticasse tarifas de importação elevadas aos seus produtos. Assim sendo, aplica-se no presente trabalho o modelo gravitacional para mensurar o efeito de criação ou desvio de comércio, resultado da aplicação de tarifas pela União Europeia com relação aos seus 48 parceiros comerciais selecionados, incluindo-se o Brasil, e também o impacto de um possível Acordo Preferencial de Comércio entre Brasil e União Europeia. A análise enfoca os efeitos para um grupo selecionado de produtos agrícolas, que recebem a incidência de picos tarifários, incluindo-se carne bovina congelada, carne bovina fresca, carne de frango, carne suína, açúcar bruto e suco de fruta. O período considerado para a análise compreende os anos de 1996 a 2013, ou seja, desde o alargamento da União Europeia no ano de 1995. O modelo gravitacional é estimado por meio do modelo de efeitos fixos e os resultados mostram a existência de desvio de comércio com relação às importações europeias de carne bovina fresca (SH 0202) e carne suína (SH 0203) e impacto positivo da concretização de um Acordo Preferencial de Comércio para carne bovina fresca (SH 0201), carne bovina congelada (SH 0202) e carne de frango (SH 0207). Tais resultados confirmam as hipóteses levantadas na literatura com relação à consolidação do referido acordo. Ou seja, os resultados indicam que o Brasil pode aumentar suas exportações de produtos agrícolas para a União Europeia caso ocorra um acordo preferencial que elimine as barreiras tarifárias impostas pelo bloco da UE. / Trade relations between the European Union (EU) and its trading partners have feature for the granting of tariff reduction or exemption for developing countries, through preferential agreements. With regard to preferential trade agreements (PTA) put in place by the European Union, stands out those performed with the group of African, Caribbean and Pacific (ACP) countries for agricultural and industrial products. The cooperative nature of politics in the ACP-EU agricultural sector has the objective of preserving the environment, food security, economic growth and sustainable development. Except for some preferred sealed agreements with some countries, the European Union has in the agricultural sector, one of the segments most subject to trade protection. With regard to Brazil, the European Union is the main market for its agricultural products. Even so, the Brazilian agricultural sector could have a better performance if the EU did not ascribe excessively high import tariffs to their products. Therefore, a gravity model is used in this analysis to measure the effect of trade creation or trade diversion as a result of the tariff applied by the European Union in relation for 48 selected trading partners, including Brazil and also the impact of a possible Preferential Trade Agreement between Brazil and the European Union. The analysis focuses on the effects for a selected group of agricultural products receiving the incidence of tariff peaks, including frozen beef, fresh beef, chicken, pork, raw sugar and fruit juice The period considered for the analysis covers the years from 1996 to 2013, which incorporates the enlargement of the European Union starting at 1995. The gravity model is estimated using the fixed effects model and the results show the existence of trade diversion with respect to European imports of fresh beef (HS 0202) and pork (HS 0203) and positive impact of the implementation of a Preferential Trade Agreement for fresh beef (HS 0201), frozen beef (HS 0202) and chicken (HS 0207). These results confirm the hypotheses rose in the literature with regard to the consolidation of the Agreement. That is, the results indicate that Brazil could increase its exports of agricultural products to the EU in the event of a preferential agreement eliminating tariff barriers imposed by the EU bloc.
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O EFEITO FRONTEIRA DO COMÉRCIO DO ESTADO DO RIO GRANDE DO SUL COM OS PAÍSES DO BRICS: UMA ANÁLISE GRAVITACIONAL / THE EFFECT OF THE BORDER TRADE OF THE STATE OF RIO GRANDE DO SUL WITH THE COUNTRIES OF THE BRICS: A GRAVITATIONAL ANALYSISMissaggia, Silvia Zanoso 17 December 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation is intended to measure the size of the home bias of commerce of the state of Rio Grande do Sul from 1999 to 2010. The size of the domestic bias gaucho trade was estimated using a gravity model, encompassing variables such as income, distance, population, and dummies adjacency and border effect. Empirically, the model was estimated with panel data via pooled OLS, and the data of bilateral trade flows correspond to trade status with the brazilian federal units and the BRICS countries. The results found for the size of home bias of commerce of the state of Rio Grande do Sul via OLS indicates that trade flows gaucho state with the other brazilian federative units is about 2.23 times larger than the state of bilateral flows Rio Grande do Sul with the BRICS countries. / Essa dissertação tem por objetivo mensurar o tamanho do viés doméstico de comércio do estado do Rio Grande do Sul no período de 1999 a 2010. O tamanho do viés doméstico de comércio gaúcho foi estimado por meio do modelo de gravidade, englobando variáveis como renda, distância, população, e dummies de adjacência e efeito fronteira. Empiricamente o modelo foi estimado com dados em painel via MQO pooled, sendo que os dados de fluxos comerciais bilaterais correspondem ao comércio do estado com as unidades federativas brasileiras e para países do BRICS. O resultado encontrado para o tamanho de viés doméstico de comércio do estado do Rio Grande do Sul aponta que os fluxos comerciais do estado gaúcho com as demais unidades federativas brasileiras é cerca de 2,23 vezes maior do que os fluxos bilaterais do estado do Rio Grande do Sul com os países do BRICS.
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DETERMINANTES DAS EXPORTAÇÕES DE CASTANHA DE CAJU DA GUINÉ- BISSAU (1986 2011): UMA ANÁLISE SOB A ÓTICA DO MODELO DE GRAVIDADE DE BERGSTRAND / DETERMINANTS OF THE EXPORTS OF GUINEA-BISSAU'S CASHEW NUTS (1986 - 2011): AN ANALYSIS FROM THE OPTICS OF THE BERGSTRAND S GRAVITY MODELCateia, Julio Vicente 21 January 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aims to analyze the determinants of cashew nuts exports from Guinea-Bissau to
India (1986-2011), by using the Bergstrand s (1985) gravity model. An equation was
estimated using panel data (OLS-pooled) and suggests that the cashew nuts exports are
negatively related to the distance between the commercial centers and positively related to the
exchange rate and gross incomes and per capita incomes, which is consistent with the
theoretical assumptions of gravity models and the seminal studies of the economic literature
with application of these models. To consider the effect of participation of the Guinea-Bissau
in international organizations, the data were stacked and separated into two periods, before
(1986-1996) and after (1997-2011) integration. Accordingly, two equations were estimated. In
the first period it was identified a positive relationship between exports of cashew nuts and
gross income, per capita income, exchange rate and distance. In the second one, the estimated
equation shows that cashew nuts exports respond negatively to the distance and to variation in
per capita income and positively to changes in exchange rate and gross income / O presente estudo tem como objetivo analisar os determinantes das exportações de castanha
de caju da Guiné-Bissau para a Índia (1986-2011), utilizando o modelo de gravidade de
Bergstrand (1985). Uma equação foi estimada através de dados em painel (MQO-pooled) e
sugere que as exportações de castanha de caju são negativamente relacionadas com a distância
entre os centros comerciais e positivamente relacionadas com a taxa de câmbio e rendas
brutas e rendas per capitas, o que é consistente com os pressupostos teóricos dos modelos
gravitacionais e com os estudos seminais da literatura econômica com a aplicação desses
modelos. Para considerar o efeito de participação da Guiné-Bissau nos organismos
internacionais, os dados foram empilhados e separados em dois períodos, antes (1986-1996) e
depois (1997-2011) da adesão. Por conseguinte, foram estimadas duas equações. No primeiro
período foi identificada uma relação positiva entre exportações de castanha de caju e a renda
bruta, a renda per capita, a taxa câmbio e a distância. Já no segundo período a equação
estimada mostra que as exportações de castanha de caju respondem negativamente à distância
e à variação da renda per capita e positivamente às variações da taxa de cambio e da renda
bruta.
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Impactos da facilitação sobre os fluxos de comércio internacional: evidências do modelo gravitacional / Impacts of facilitation upon international trade flows: evidences from gravity modelMauricio Jorge Pinto de Souza 16 June 2009 (has links)
A intensificação do comércio internacional e a liberalização comercial ocorrida nos últimos anos têm aumentado a importância relativa dos procedimentos de fronteira como determinante dos custos de comercialização associados ao comércio internacional. Uma parcela desses custos está associada a atrasos portuários, a ausência de transparência na aplicação de regras, a burocracia e a procedimentos aduaneiros desatualizados. Nesse contexto, a facilitação de comércio começou a receber destaque no cenário político internacional. Entendida como medidas que reduzem os custos de comercialização internacional, a facilitação de comércio tornou-se tópico de discussão na OMC a partir da conferência Ministerial de Cingapura de 1996. Estudos relacionados à facilitação de comércio, principalmente estudos que abrangem o Brasil e seus parceiros comerciais ainda são raros. O presente estudo tencionou contribuir nessa direção avaliando os efeitos da facilitação de comércio, definida em termos da transparência da política comercial, sobre o padrão de comércio bilateral de um conjunto de 43 países que inclui o Brasil e alguns de seus principais parceiros comerciais. Para isso, são descritas primeiramente as relações entre a facilitação de comércio, transparência da política comercial e os fluxos comerciais. A idéia central é que a reforma da política comercial que promova a transparência, através de maior previsibilidade e simplificação, pode contribuir para a redução dos custos de comercialização associados ao comércio internacional e ampliar os fluxos de comércio entre os países. A partir de indicadores de facilitação de comércio relacionados à transparência da política comercial são construídos, para cada país da amostra, três índices de transparência utilizando a técnica estatística multivariada da análise fatorial: dois índices de transparência nas importações e um índice de transparência nas exportações. A relação desses índices com o padrão de comércio bilateral entre os países é estimada utilizando um modelo gravitacional construído com dados de comércio bilateral dos 43 países desagregados em Capítulos do Sistema Harmonizado. O modelo gravitacional é estimado através do modelo de efeitos fixos e os resultados indicam que os índices de transparência nas importações e o índice de transparência nas exportações estão positivamente associados com o comércio bilateral e são estatisticamente significativos. Dessa maneira, a introdução de reformas nas áreas de facilitação de comércio, que levariam a um incremento relativo dos índices de transparência, pode resultar na ampliação do comércio entre os países. / The intensification of international trade and the trade liberalization that occurred in the last years have increased the relative importance of border procedures as a determinant of trade costs associated to international trade. These costs are partly associated to delay in port operations, lack of transparency in rule applications, bureaucracy and outdated customs procedures. In this context, trade facilitation became increasingly important in the international political scenario. Trade facilitation is interpreted as measures that reduce international trade costs and started to be discussed at the WTO from the Singapore ministerial conference of 1996. Studies on trade facilitation, particularly including Brazilian and trade partner issues, are still scarce, therefore the present study aims to contribute in this direction evaluating the effects of trade facilitation, defined as the transparency of trade policy. It is applied to the pattern of bilateral trade of a 43 - country set including Brazil and some of its major trade partners. For that purpose, the relations between trade facilitation, transparency of trade policy and trade flows are firstly described. The central idea is that the trade policy reform that promotes transparency through greater predictability and simplification can contribute to reduce trade costs associated with international trade and expand trade flows between countries. Based on trade facilitation indicators related to trade policy, three transparency indexes are constructed for each country of the sample, using multivariate statistics and factor analysis: two transparency indexes for imports and one transparency index for exports. The relation of these indexes with the bilateral trade pattern between countries is estimated using a gravity model constructed with bilateral trade data of the 43 countries disaggregated in chapters of the Harmonized System. The gravity model is estimated by a fixed effects model and the results indicate that the transparency indexes for imports and exports are positively associated with bilateral trade and are statistically significant. Therefore, reforms in trade facilitation areas that would lead to a relative increase of the transparency index can be an way to expand trade between the countries.
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