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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

A dinâmica da estrutura da indústria de carne de frango no Brasil

Oliveira, Carlos Alberto Oliveira de January 2011 (has links)
A indústria de carne de frango no Brasil cresceu e figura, desde 2004, como maior exportadora mundial desta carne, mesmo destinando menos de 30% do volume total produzido no país para o mercado internacional. No Brasil, a carne de frango é a mais consumida, desde 2006, entre as carnes. Neste contexto, é importante o entendimento de como a indústria evoluiu para atingir o patamar atual. Visando analisar a dinâmica da estrutura da indústria de carne de frango no Brasil entre os anos de 2000 e 2010, as Teorias da Organização Industrial e da Localização foram adotadas na pesquisa e utilizou-se o método quantitativo com dados secundários do conjunto de empresas responsáveis pelo abate e industrialização de frangos no Brasil. Para o período entre 2000 e 2010, analisou-se a mobilidade regional das operações de abate; a concentração de mercado foi mensurada, pelos índices Razão de Concentração e Herfindahl-Hirschman; e também se avaliou a mudança de posições das empresas pela análise de turnover. Para os índices de concentração e para o turnover adotou-se como critérios de análise o número de frangos abatidos e o volume de carne de frango exportada de cada empresa anualmente. Os resultados demonstram expansão da indústria de carne de frango e que seu direcionamento está associado à disponibilidade de insumos para alimentação dos frangos. Na região Centro-Oeste, observa-se o maior incremento de participação no abate de frangos no Brasil. Na análise das variáveis estruturais, constata-se que a concentração pelo índice HH é classificada como não concentrada no abate, com exceção de 2009, ano em que as duas maiores empresas responderam por mais de 44% dos frangos abatidos no Brasil. Já as exportações caracterizam-se como moderadamente concentradas. Ao longo do período analisado, ocorre um aumento da concentração no abate e uma moderada redução da concentração nas exportações. Porém, na segunda metade dos anos 2000, registra-se uma intensificação do aumento da concentração no abate de frangos e uma inversão da tendência de queda nas exportações. Como fator, parcial, de explicação para tal fenômeno tem-se os processos de fusões e aquisições, que se intensificaram nessa indústria na segunda metade dos anos 2000. Pela análise de turnover, verifica-se que há mudanças de posições entre as empresas e que estas, também, se intensificaram na segunda metade dos anos 2000. Evidenciam-se mudanças no padrão de consumo domiciliar no Brasil e na pauta das exportações, que indicam decréscimo do frango inteiro e acréscimo desta carne em cortes e de produtos elaborados. Constata-se que a indústria amplia seus mercados internacionais e tem-se a perspectiva de aumento da participação de produtos industrializados na pauta das exportações. Conclui-se que os movimentos ocorridos caracterizam mudanças na estrutura da indústria de carne de frango no Brasil. E nesta trajetória constata-se como importantes direcionadores as fusões e aquisições ocorridas e o aumento do tamanho do mercado. Espera-se, com esta pesquisa, contribuir com informações sobre a evolução recente da indústria, o que pode auxiliar nas proposições de políticas públicas e nas orientações das empresas que atuam, ou venham a entrar nesta indústria. / The Brazilian chicken meat industry has grown and stands out, since 2004, as world’s major exporter of this meat, even allocating less than 30% of the total amount produced in this country to international trade. In Brazil, chicken meat has been the most consumed within the meat types, since 2006. Given this perspective, it is important to understand how the industry has evolved to reach such status. Aiming to analyze the structural dynamics of chicken meat industry in Brazil in 2000 and 2010, Industrial Organization and Location theories were adopted , a quantitative method was used, with secondary data regarding poultry slaughtering and processing companies. Between 2000 and 2010, regional mobility of the slaughtering operations was analyzed; market concentration has been measured through Concentration Ratio and Herfindahl-Hirschman indexes. Changes in the ranking of companies were also assessed, through turnover analysis. In order to undertake the market concentration measurement and the turnover analysis, the number of slaughtered chickens and the volume of chicken meat exported by each company, annually, were adopted as analysis criterion. The results show an expansion of the chicken meat industry, which directioning is related to the availability of inputs for chicken feed. In the Central-West Region, one observes the highest increase in participation in chicken slaughtering in Brazil. When analyzing the structural variables, one notes that market concentration is characterized as not concentrated regarding slaughtering, the exception being 2009, when the two largest companies accounted for more than 44% of chicken slaughtered in Brazil. Concerning exports, they are characterized as moderately concentrated. Throughout the time period that has been analyzed, there is an increase in slaughtering concentration and a moderate reduction in exports concentration. However, in the second half of decade 2000-2010, one records intensification on the concentration increase in chicken slaughtering and an inversion on the decrease trend in exports. As a partial factor of explanation for such phenomenon, there are mergers and acquisition processes, intensified within this industry during the second half of the decade 2000-2010. By means of turnover analysis, one verifies that there are changes in the ranking of the companies, phenomenon that has also been during the second half of the decade 2000-2010. Changes in the domestic consumption patterns in Brazil, as well as in its exports portfolio are observed and indicate a decrease of the whole chicken figures and an increase of cuts and elaborated products. It is found that the industry expands its international markets and there is a perspective of increase in the participation of industrialized products in the exports portfolio. It can be concluded that movements occurred during the observed time period characterize changes in chicken meat industry, in Brazil. And in this evolution it can be seen as important drivers mergers and acquisitions and the increasing of size market. This research is expected to contribute with information on recent developments in the industry, by means of assistance for proposal for public policies, and orientations to companies currently operating in this industry and of those that could possibly enter this market.
12

A dinâmica da estrutura da indústria de carne de frango no Brasil

Oliveira, Carlos Alberto Oliveira de January 2011 (has links)
A indústria de carne de frango no Brasil cresceu e figura, desde 2004, como maior exportadora mundial desta carne, mesmo destinando menos de 30% do volume total produzido no país para o mercado internacional. No Brasil, a carne de frango é a mais consumida, desde 2006, entre as carnes. Neste contexto, é importante o entendimento de como a indústria evoluiu para atingir o patamar atual. Visando analisar a dinâmica da estrutura da indústria de carne de frango no Brasil entre os anos de 2000 e 2010, as Teorias da Organização Industrial e da Localização foram adotadas na pesquisa e utilizou-se o método quantitativo com dados secundários do conjunto de empresas responsáveis pelo abate e industrialização de frangos no Brasil. Para o período entre 2000 e 2010, analisou-se a mobilidade regional das operações de abate; a concentração de mercado foi mensurada, pelos índices Razão de Concentração e Herfindahl-Hirschman; e também se avaliou a mudança de posições das empresas pela análise de turnover. Para os índices de concentração e para o turnover adotou-se como critérios de análise o número de frangos abatidos e o volume de carne de frango exportada de cada empresa anualmente. Os resultados demonstram expansão da indústria de carne de frango e que seu direcionamento está associado à disponibilidade de insumos para alimentação dos frangos. Na região Centro-Oeste, observa-se o maior incremento de participação no abate de frangos no Brasil. Na análise das variáveis estruturais, constata-se que a concentração pelo índice HH é classificada como não concentrada no abate, com exceção de 2009, ano em que as duas maiores empresas responderam por mais de 44% dos frangos abatidos no Brasil. Já as exportações caracterizam-se como moderadamente concentradas. Ao longo do período analisado, ocorre um aumento da concentração no abate e uma moderada redução da concentração nas exportações. Porém, na segunda metade dos anos 2000, registra-se uma intensificação do aumento da concentração no abate de frangos e uma inversão da tendência de queda nas exportações. Como fator, parcial, de explicação para tal fenômeno tem-se os processos de fusões e aquisições, que se intensificaram nessa indústria na segunda metade dos anos 2000. Pela análise de turnover, verifica-se que há mudanças de posições entre as empresas e que estas, também, se intensificaram na segunda metade dos anos 2000. Evidenciam-se mudanças no padrão de consumo domiciliar no Brasil e na pauta das exportações, que indicam decréscimo do frango inteiro e acréscimo desta carne em cortes e de produtos elaborados. Constata-se que a indústria amplia seus mercados internacionais e tem-se a perspectiva de aumento da participação de produtos industrializados na pauta das exportações. Conclui-se que os movimentos ocorridos caracterizam mudanças na estrutura da indústria de carne de frango no Brasil. E nesta trajetória constata-se como importantes direcionadores as fusões e aquisições ocorridas e o aumento do tamanho do mercado. Espera-se, com esta pesquisa, contribuir com informações sobre a evolução recente da indústria, o que pode auxiliar nas proposições de políticas públicas e nas orientações das empresas que atuam, ou venham a entrar nesta indústria. / The Brazilian chicken meat industry has grown and stands out, since 2004, as world’s major exporter of this meat, even allocating less than 30% of the total amount produced in this country to international trade. In Brazil, chicken meat has been the most consumed within the meat types, since 2006. Given this perspective, it is important to understand how the industry has evolved to reach such status. Aiming to analyze the structural dynamics of chicken meat industry in Brazil in 2000 and 2010, Industrial Organization and Location theories were adopted , a quantitative method was used, with secondary data regarding poultry slaughtering and processing companies. Between 2000 and 2010, regional mobility of the slaughtering operations was analyzed; market concentration has been measured through Concentration Ratio and Herfindahl-Hirschman indexes. Changes in the ranking of companies were also assessed, through turnover analysis. In order to undertake the market concentration measurement and the turnover analysis, the number of slaughtered chickens and the volume of chicken meat exported by each company, annually, were adopted as analysis criterion. The results show an expansion of the chicken meat industry, which directioning is related to the availability of inputs for chicken feed. In the Central-West Region, one observes the highest increase in participation in chicken slaughtering in Brazil. When analyzing the structural variables, one notes that market concentration is characterized as not concentrated regarding slaughtering, the exception being 2009, when the two largest companies accounted for more than 44% of chicken slaughtered in Brazil. Concerning exports, they are characterized as moderately concentrated. Throughout the time period that has been analyzed, there is an increase in slaughtering concentration and a moderate reduction in exports concentration. However, in the second half of decade 2000-2010, one records intensification on the concentration increase in chicken slaughtering and an inversion on the decrease trend in exports. As a partial factor of explanation for such phenomenon, there are mergers and acquisition processes, intensified within this industry during the second half of the decade 2000-2010. By means of turnover analysis, one verifies that there are changes in the ranking of the companies, phenomenon that has also been during the second half of the decade 2000-2010. Changes in the domestic consumption patterns in Brazil, as well as in its exports portfolio are observed and indicate a decrease of the whole chicken figures and an increase of cuts and elaborated products. It is found that the industry expands its international markets and there is a perspective of increase in the participation of industrialized products in the exports portfolio. It can be concluded that movements occurred during the observed time period characterize changes in chicken meat industry, in Brazil. And in this evolution it can be seen as important drivers mergers and acquisitions and the increasing of size market. This research is expected to contribute with information on recent developments in the industry, by means of assistance for proposal for public policies, and orientations to companies currently operating in this industry and of those that could possibly enter this market.
13

Estimando o impacto do estoque de capital publico sobre o PIB per capita na presenÃa de mudanÃa estrutural. / Esteem the impact of the capital supply I publish on the GIP for head in the presence of structural change

Jimmy Lima de Oliveira 31 October 2006 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente trabalho estima a elasticidade produto-gasto pÃblico para economia brasileira, no perÃodo de 1950 a 2003, utilizando um modelo vetorial de correÃÃo de erro (VECM) para controlar possÃveis mudanÃas estruturais nas sÃries. Quando existem mudanÃas estruturais, os vÃrios testes estatÃsticos de Dickey-Fuller sÃo viesados em direÃÃo da nÃo rejeiÃÃo de uma raiz unitÃria. Este viÃs significa que o teste de Dickey-Fuller à viesado em direÃÃo da hipÃtese nula de uma raiz unitÃria, mesmo se a sÃrie à estacionÃria dentro de cada subperÃodo. Sem controlar para mudanÃas estruturais, os testes de cointegraÃÃo podem apresentar resultados enganosos, e as estimativas obtidas podem ser viesadas. / Aiming to estimate the elasticity product-public expenditure to the Brazilian economy, during the period 1950-2003, it was used a vector error correction model (VECM) to control for possible structural changes in the series. When structural changes were observed, many of the Dickey-Fuller statistic tests are biased towards the non-rejection of the existence of a unit root. This bias means that the Dickey-Fuller test is biased towards the null hypothesis of unit root, even if the series is stationary within each sub period. Without controlling for structural changes, the cointegration tests may present deceiving results and the estimates obtained may be biased.
14

Modelling nonlinearities in long-memory time series : simulation and empirical studies / Modélisation des non linéarités dans des séries à mémoire longue : simulation et études empiriques

Belkhouja, Mustapha 29 June 2010 (has links)
Cette thèse porte sur l'identification et l'estimation des ruptures structurelles pouvant affecter des données économiques et financières à mémoire longue. Notre étude s'est limitée dans les trois premiers chapitres au cadre univarié où nous avons modélisé la dépendance de long terme et les changements structurels simultanément et séparément au niveau de la moyenne ainsi que la volatilité. Dans un premier temps nous n'avons tenu compte que des sauts instantanés d'état ensuite nous nous sommes intéressés à la possibilité d'avoir des changements graduels et lisses au cours du temps grâce à des modèles nonlinéaires plus complexes. Par ailleurs, des expériences de simulation ont été menées dans le but d'offrir une analyse comparative des méthodes utilisées et d'attester de la robustesse des tests sous certaines conditions telle que la présence de la mémoire longue dans la série. Ce travail s'est achevé sur une extension aux modèles multivariés.Ces modèles permettent de rendre compte des mécanismes de propagation d'une variation d'une série sur l'autre et d'identifier les liens entre les variables ainsi que la nature des ces liens. Les interactions entre les différentes variables financières ont été analysées tant à court terme qu'à long terme. Bien que le concept du changement structurel n'a pas été abordé dans ce dernier chapitre, nous avons pris en compte l'effet d'asymétrie et de mémoire longue dans la modélisation de la volatilité. / This dissertation deals with the detection and the estimation of structural changes in long memory economic and financial time series. Within the rest three chapters we focused on the univariate case to model both the long range dependence and structural changes in the mean and the volatility of the examined series. In the beginning we just take into account abrupt regime switches but after we use more developed nonlinear models in order to capture the smooth time variations of the dynamics. Otherwise we analyse the efficiency of various techniques permitting to select the number of breaks and we assess the robustness of the used tests in a long memory environment via simulations. Last, this thesis was completed by an extension to multivariate models. These models allow us to detect the impact of some series on the others and identify the relationships among them. The interdependencies between the financial variables were studied and analysed both in the short and the long range. While structural changes were not considered in the last chapter, our multivariate model takes into account asymmetry effects and the long memory behaviour in the volatility.
15

A Laser Raman spectroscopic study of the pH induced structural changes in Guanosine-5’ monophosphate and its derivatives

Pambi, Daniel 01 December 1988 (has links)
The purpose of this study was to determine the protonation sites in guanosine-5'-monophosphate (5'-GMP), and to correlate the ease of protonation with the chemical nature and composition of substituent groups. The laser Raman spectra of 5'-GMP, 7-methyl-guanosine-5'-monophosphate (m7-GMP), and 8-bromoguanosine-5'-monophosphate (8-Br-GMP) at various pH and pD values were recorded with a Spex Ramalog-6 spectrometer. Based on the spectral changes observed in these studies, the preferred order of protonation sites for 5'-GMP and 8-Br-GMP is N7, 06 and N3. In the case of m7-GMP, the preferred sites are 06 and N3. The opening of the imidazole ring in m7-GMP is observed at pH value of about 9.4. It appears that the presence of the methyl group has a stabilizing effect on the protonated (keto) species. As expected, the vibrational modes of the phosphate group are unaffected by substituents on the guanine part of 5'-GMP. The complete spectra and vibrational assignments for 5'-GMP, m7- GMP and 8-Br-GMP are presented in this thesis.
16

Static structure and dynamical structural changes of nanoparticles using XFEL pulses / XFELパルスを利用したナノ粒子の静的構造・動的構造変化の研究

Hiraki(Nishiyama), Toshiyuki 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22239号 / 理博第4553号 / 新制||理||1654(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)准教授 松田 和博, 教授 田中 耕一郎, 教授 佐々 真一 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
17

Structural Changes and Urban Transformations-Accidental Housing Revival, Case Study of Niš, Serbia

Vranic, Petar January 2012 (has links)
This master thesis is intended as a contribution to the understanding of the influencestructural changes has on urban transformation in housing domain, by focusing onmechanisms behind the upgrading as accidental model for regeneration of the collectivehousing. In particular, the aim is to do so in relation to a comparison between differentoperational scales on which process is carried out. The process is investigated at the city,neighborhood and street/square scale. With the use of qualitative methods, such asinterviews, in depth analysis of policies and regulations and observations, differences inmanifestation of the regeneration on different scales are discovered. It is suggested thatundefined strategy, indifferent attitude of local authorities, inconsistent legislativeenvironment, disconnection between the operational scales and presence of the market asessential driving force of the process, results in asymmetric outcomes of upgrading, both inphysical and social terms. But on the other hand, in respect to wider political and economicalenvironment in which regeneration happened, it is acknowledged that considerable housingstock is renovated and living standards are improved. The most critical issue in the process isproved to be the uneven awareness of the importance of the regeneration among the actorsat different scales and consequently their performance in respect to it. Furthermore,influence of upgrading on the community life and social relation in the regeneratedneighborhoods are totally neglected, which has for its consequences decreased use ofcommon space between the buildings and erosion of existed communities. It is proved alsothat fully market driven regeneration has rather regressive consequences on urbantransformation in context of Nis but in same time gives valuable lessons for improvement ofthe future upgrading as regeneration model for collective housing. Based on these lessons,adaptive policy changes are suggested and platform for further studies in system or processoriented urban regeneration and design is established. Thesis is organized as follows: firstmethodological approach is explained, second it situate problem in wider regional and localcontext in respect to urban transformation and housing trends, third thesis discuss analysisof operational scales and conclude with final cross-scale discussion and potentials for furtherresearch.
18

ECONOMIC ANALYSIS ON PRODUCTION CHANGES, MARKET INTEGRATION AND EXPORT CHALLENGES OF COFFEE SECTOR IN INDONESIA / インドネシアコーヒー産業の構造変化、市場統合と輸出競争に関する経済分析

Agus, Nugroho 23 May 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19902号 / 農博第2185号 / 新制||農||1044(附属図書館) / 学位論文||H28||N5006(農学部図書室) / 32979 / 京都大学大学院農学研究科生物資源経済学専攻 / (主査)教授 福井 清一, 教授 伊藤 順一, 准教授 沈 金虎 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
19

Investigation of the Influence of Transition Metal Ions on the Fe-S Cluster Biosynthesis Protein SufU

Jayawardhana, W. Geethamala Dhananjalee 07 December 2015 (has links)
No description available.
20

Modeling and Characterization of Dynamic Changes in Biological Systems from Multi-platform Genomic Data

Zhang, Bai 30 September 2011 (has links)
Biological systems constantly evolve and adapt in response to changed environment and external stimuli at the molecular and genomic levels. Building statistical models that characterize such dynamic changes in biological systems is one of the key objectives in bioinformatics and computational biology. Recent advances in high-throughput genomic and molecular profiling technologies such as gene expression and and copy number microarrays provide ample opportunities to study cellular activities at the individual gene and network levels. The aim of this dissertation is to formulate mathematically dynamic changes in biological networks and DNA copy numbers, to develop machine learning algorithms to learn these statistical models from high-throughput biological data, and to demonstrate their applications in systems biological studies. The first part (Chapters 2-4) of the dissertation focuses on the dynamic changes taking placing at the biological network level. Biological networks are context-specific and dynamic in nature. Under different conditions, different regulatory components and mechanisms are activated and the topology of the underlying gene regulatory network changes. We report a differential dependency network (DDN) analysis to detect statistically significant topological changes in the transcriptional networks between two biological conditions. Further, we formalize and extend the DDN approach to an effective learning strategy to extract structural changes in graphical models using l1-regularization based convex optimization. We discuss the key properties of this formulation and introduce an efficient implementation by the block coordinate descent algorithm. Another type of dynamic changes in biological networks is the observation that a group of genes involved in certain biological functions or processes coordinate to response to outside stimuli, producing distinct time course patterns. We apply the echo stat network, a new architecture of recurrent neural networks, to model temporal gene expression patterns and analyze the theoretical properties of echo state networks with random matrix theory. The second part (Chapter 5) of the dissertation focuses on the changes at the DNA copy number level, especially in cancer cells. Somatic DNA copy number alterations (CNAs) are key genetic events in the development and progression of human cancers, and frequently contribute to tumorigenesis. We propose a statistically-principled in silico approach, Bayesian Analysis of COpy number Mixtures (BACOM), to accurately detect genomic deletion type, estimate normal tissue contamination, and accordingly recover the true copy number profile in cancer cells. / Ph. D.

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