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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.
1

Determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume de vendas de gasolina comum : um estudo com dados em painel (2010-2012)

Almeida, Reginaldo Sena de January 2016 (has links)
Este estudo tem como objetivo identificar evidências empíricas sobre os determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume mensal de vendas de gasolina comum. Para tanto, com base numa amostra de 372 postos de combustíveis, operando sob a bandeira da Petrobras Distribuidora, para os quais foram amostradas observações sobre o volume mensal de gasolina comum comercializado e seu respectivo preço de venda, o preço de venda do álcool combustível, a renda do consumidor e o estoque da frota de veículos leves, compondo um painel completo de dados, para o período compreendido entre janeiro de 2010 a dezembro de 2012. Assim, utilizando as ferramentas econométricas para dados em painel, concluiu-se que a abordagem dos efeitos fixos é a que melhor se adequa aos dados da amostra, evidenciando que há influência de efeitos específicos (heterogeneidade não observável) inerentes a cada unidade de corte transversal sobre o respectivo volume de vendas de gasolina. Além disso, foram estimadas as elasticidades da demanda em relação ao preço, à renda e ao estoque da frota de veículos, bem como a elasticidade-preço cruzada em relação aoálcool combustível.A demanda por gasolina comum mostrou-se elástica com relação ao seu preço. Foi confirmado o corretoemprego do etanol como um substituto imperfeito da gasolina. Constatou-se que, o estoque da frota de veículos tende a ter influênciasignificativa e positiva sobre a demanda de gasolina. Entretanto, contrariando a teoria econômica, foi rejeitada a hipótese de influência da variável renda sobre as vendas de gasolina comum. / This study aims to identify empirical evidence on the determinants of the performance of the Brazilian urban fuel stations, in terms of monthly sales of gasoline. Therefore, based on a sample of 372 gas stations operating under the banner of PetrobrasDistribuidora, for which were sampled observations on the monthly volume of traded gasoline and its respective saleprice, the sale price of ethanol, consumer income and the stock of the light vehicle fleet, composing a complete panel data for the period from January 2010 to December 2012. Thus, using econometric tools to panel data, it was concluded that the approach the fixed effects is the best suited to the sample data, evidencing the influence of specific effects (unobservable heterogeneity) inherent in every cross-section unit on the respective volume of gas sales. Moreover, the demand elasticities were estimated in relation to price, income and stock of the vehicle fleet, as well as the cross-price elasticity in relation to ethanol. Demand for regular gasoline was shown to be elastic with respect to its price. It was confirmed the use of ethanol as an imperfect substitute for gasoline. It was found that the stock of vehicle fleet tends to have significant and positive influence on the demand for gasoline. However, contrary to economic theory, the hypothesis of the influence of variable income on sales of gasoline was rejected.
2

Determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume de vendas de gasolina comum : um estudo com dados em painel (2010-2012)

Almeida, Reginaldo Sena de January 2016 (has links)
Este estudo tem como objetivo identificar evidências empíricas sobre os determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume mensal de vendas de gasolina comum. Para tanto, com base numa amostra de 372 postos de combustíveis, operando sob a bandeira da Petrobras Distribuidora, para os quais foram amostradas observações sobre o volume mensal de gasolina comum comercializado e seu respectivo preço de venda, o preço de venda do álcool combustível, a renda do consumidor e o estoque da frota de veículos leves, compondo um painel completo de dados, para o período compreendido entre janeiro de 2010 a dezembro de 2012. Assim, utilizando as ferramentas econométricas para dados em painel, concluiu-se que a abordagem dos efeitos fixos é a que melhor se adequa aos dados da amostra, evidenciando que há influência de efeitos específicos (heterogeneidade não observável) inerentes a cada unidade de corte transversal sobre o respectivo volume de vendas de gasolina. Além disso, foram estimadas as elasticidades da demanda em relação ao preço, à renda e ao estoque da frota de veículos, bem como a elasticidade-preço cruzada em relação aoálcool combustível.A demanda por gasolina comum mostrou-se elástica com relação ao seu preço. Foi confirmado o corretoemprego do etanol como um substituto imperfeito da gasolina. Constatou-se que, o estoque da frota de veículos tende a ter influênciasignificativa e positiva sobre a demanda de gasolina. Entretanto, contrariando a teoria econômica, foi rejeitada a hipótese de influência da variável renda sobre as vendas de gasolina comum. / This study aims to identify empirical evidence on the determinants of the performance of the Brazilian urban fuel stations, in terms of monthly sales of gasoline. Therefore, based on a sample of 372 gas stations operating under the banner of PetrobrasDistribuidora, for which were sampled observations on the monthly volume of traded gasoline and its respective saleprice, the sale price of ethanol, consumer income and the stock of the light vehicle fleet, composing a complete panel data for the period from January 2010 to December 2012. Thus, using econometric tools to panel data, it was concluded that the approach the fixed effects is the best suited to the sample data, evidencing the influence of specific effects (unobservable heterogeneity) inherent in every cross-section unit on the respective volume of gas sales. Moreover, the demand elasticities were estimated in relation to price, income and stock of the vehicle fleet, as well as the cross-price elasticity in relation to ethanol. Demand for regular gasoline was shown to be elastic with respect to its price. It was confirmed the use of ethanol as an imperfect substitute for gasoline. It was found that the stock of vehicle fleet tends to have significant and positive influence on the demand for gasoline. However, contrary to economic theory, the hypothesis of the influence of variable income on sales of gasoline was rejected.
3

Determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume de vendas de gasolina comum : um estudo com dados em painel (2010-2012)

Almeida, Reginaldo Sena de January 2016 (has links)
Este estudo tem como objetivo identificar evidências empíricas sobre os determinantes do desempenho dos postos de combustíveis urbanos brasileiros, em termos do volume mensal de vendas de gasolina comum. Para tanto, com base numa amostra de 372 postos de combustíveis, operando sob a bandeira da Petrobras Distribuidora, para os quais foram amostradas observações sobre o volume mensal de gasolina comum comercializado e seu respectivo preço de venda, o preço de venda do álcool combustível, a renda do consumidor e o estoque da frota de veículos leves, compondo um painel completo de dados, para o período compreendido entre janeiro de 2010 a dezembro de 2012. Assim, utilizando as ferramentas econométricas para dados em painel, concluiu-se que a abordagem dos efeitos fixos é a que melhor se adequa aos dados da amostra, evidenciando que há influência de efeitos específicos (heterogeneidade não observável) inerentes a cada unidade de corte transversal sobre o respectivo volume de vendas de gasolina. Além disso, foram estimadas as elasticidades da demanda em relação ao preço, à renda e ao estoque da frota de veículos, bem como a elasticidade-preço cruzada em relação aoálcool combustível.A demanda por gasolina comum mostrou-se elástica com relação ao seu preço. Foi confirmado o corretoemprego do etanol como um substituto imperfeito da gasolina. Constatou-se que, o estoque da frota de veículos tende a ter influênciasignificativa e positiva sobre a demanda de gasolina. Entretanto, contrariando a teoria econômica, foi rejeitada a hipótese de influência da variável renda sobre as vendas de gasolina comum. / This study aims to identify empirical evidence on the determinants of the performance of the Brazilian urban fuel stations, in terms of monthly sales of gasoline. Therefore, based on a sample of 372 gas stations operating under the banner of PetrobrasDistribuidora, for which were sampled observations on the monthly volume of traded gasoline and its respective saleprice, the sale price of ethanol, consumer income and the stock of the light vehicle fleet, composing a complete panel data for the period from January 2010 to December 2012. Thus, using econometric tools to panel data, it was concluded that the approach the fixed effects is the best suited to the sample data, evidencing the influence of specific effects (unobservable heterogeneity) inherent in every cross-section unit on the respective volume of gas sales. Moreover, the demand elasticities were estimated in relation to price, income and stock of the vehicle fleet, as well as the cross-price elasticity in relation to ethanol. Demand for regular gasoline was shown to be elastic with respect to its price. It was confirmed the use of ethanol as an imperfect substitute for gasoline. It was found that the stock of vehicle fleet tends to have significant and positive influence on the demand for gasoline. However, contrary to economic theory, the hypothesis of the influence of variable income on sales of gasoline was rejected.
4

Filtros de cartéis baseados em dinâmicas de preço: uma aplicação ao varejo de combustíveis do Brasil

Silva, André Suriane da 27 April 2016 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-28T12:19:36Z No. of bitstreams: 1 andresurianedasilva.pdf: 5569442 bytes, checksum: 9543cb88ee183f3ffc1ddef094863011 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-28T12:26:01Z (GMT) No. of bitstreams: 1 andresurianedasilva.pdf: 5569442 bytes, checksum: 9543cb88ee183f3ffc1ddef094863011 (MD5) / Made available in DSpace on 2016-07-28T12:26:01Z (GMT). No. of bitstreams: 1 andresurianedasilva.pdf: 5569442 bytes, checksum: 9543cb88ee183f3ffc1ddef094863011 (MD5) Previous issue date: 2016-04-27 / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Este trabalho consiste em identificar e realizar a aplicação de metodologias capazes de filtrar comportamentos anticompetitivos através da análise da dinâmica de preços praticados pelas firmas no mercado de gasolina a varejo do Brasil. O objetivo foi avaliar métodos capazes de filtrar mercados com maior potencial de conluio, analisando padrões de precificação próprios de cartel no setor. A principal justificativa para este estudo, é contribuir na tarefa de reunião de indícios da existência de cartel para o SBDC (Sistema Brasileiro de Defesa da Concorrência), que ainda carece de estudos aprofundados sobre instrumentos de detecção de cartéis. Para a execução dos objetivos, considerou-se os casos de cartel julgados pelo CADE, em conjunto com a caracterização do mercado. Os padrões de precificação associados aos mercados colusivos foram comparados com dados simulados de concorrência, por meio da construção de indicadores estimados por métodos de séries de tempo, para compor estatísticas próprias de cada natureza competitiva. Os modelos de séries de tempo utilizados foram baseados em testes de: cointegração, assimetria de preço, variância, quebras estruturais e mudanças de regime. Por fim, os indicadores foram avaliados quanto à capacidade de diferenciar comportamento colusivo de competitivo no mercado de gasolina a varejo do Brasil, e conjuntamente foi construído um indicador para diferenciação destes comportamentos. Os resultados gerais mostraram que dinâmicas de preço são relevantes para filtrar cartel, sendo as análises de variância ao longo do tempo, variância entre firmas e mudanças de regime de precificação, os mais significativos para inferir a possibilidade de conluio. / This work aims to identify and implement methodologies capable of filtering anticompetitive behavior by analyzing the dynamics of firms’ prices in the Brazil’s retail gas market. The objective was to evaluate methods capable to filter markets with the greatest collusion potential, analyzing pricing patterns similar to ones used by the sector’s cartels. The main reason for this study is to contribute in the existing cartel evidences to the SBDC (Brazilian System of Competition Defense), which still lacks depth studies on cartel detection instruments. To implement the proposed objectives, it analyzed the cartel cases judged by CADE along with the characterization of the market. The pricing patterns associated with collusive market were compared with simulated competition data, through the construction of indicators estimated by time series methods to compose own statistics of each competitive nature. The time series models chosen were based on the tests of: cointegration, price asymmetry, variance, structural breaks and changes of regimes. Finally, it evaluated the indicators on their ability to differentiate competitive from collusive behavior in Brazil’s retail gas market, also it was built an indicator to differentiate these behaviors. The overall results showed that are relevant dynamic price for filtering cartel being analyzes of variance over time , variance between firms and pricing regime changes, the most significant to infer the possibility of collusion.
5

Drivers influencing the end price of fuel in the Czech Republic and implications for relevant businesses / Elementy ovlivňující koncovou cenu paliv v České republice a implikace pro relevantní společnosti

Fingl, Filip January 2013 (has links)
This thesis deals with understanding drivers influencing the end price of fuel in the Czech Republic and ramifications for relevant companies. Its aim is to provide a comprehensive understanding of all relevant elements have been influencing end prices of gasoline and diesel during last 8 years, understand their leverage and uncover which of those were the most important for this development. These are then researched using mainly graphical analysis and basic statistical tools. The delivery is that both prices of gasoline and diesel are highly correlated with the price development of crude oil and the prices of their respective commoditized barges expressed in the nominal value of CZK. It was also discovered that there are visible tendencies for asymmetrical pricing reaction and reaction lags, which could serve as a basis for a follow-up work. Based on these findings several conclusive recommendations for relevant companies were built and delivered.
6

Avalia??o de HPA e BTEX no solo e ?gua subterr?nea, em postos de revenda de combust?veis: estudo de caso na cidade de Natal -RN

Anjos, Raoni Batista dos 14 December 2012 (has links)
Made available in DSpace on 2014-12-17T14:08:52Z (GMT). No. of bitstreams: 1 RaoniBA_DISSERT.pdf: 2283831 bytes, checksum: 9e3bfc1213fc5b5ac439fb175ddc5631 (MD5) Previous issue date: 2012-12-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The retail fuel stations are partially or potentially polluters and generators of environmental accidents, potentially causing contamination of underground and surface water bodies, soil and air. Leaks in fuel retail stations? underground storage systems are often detected in Brazil and around the world. Monoaromatic hydrocarbons, BTEX (benzene, toluene, ethylbenzene and xylenes) and polycyclic aromatic hydrocarbons (PAHs) are an indication of the presence of contamination due to its high toxicity. This paper presents a case study of contamination in a Fuel Retail Station by petroleum derivative products in the city of Natal. For identification and quantification of the hydrocarbons, EPA analytical methods were used. The values of benzene quantified by EPA method 8021b CG-PID/FID, ranged from 1.164 to 4.503 mg.Kg-1 in soil samples, and from 12.10 to 27,639 μg.L-1 in underground water samples. Among the PAHs, naphthalene and anthracene showed the most significant results in soil samples, 0.420 to 15.46 mg.Kg-1 and 0.110 to 0,970 mg.Kg-1, respectively. In underground water samples, the results for Naphthalene varied between 0.759 and 614.7 μg.L-1. PAHs were quantified by EPA Method 8270 for GCMS. All of the results for the chemical analysis were compared with the values for the CONAMA 420/2009 resolution. The results for benzene (27,639 μg.L-1) showed levels highly above the recommended by the CONAMA 420 resolution, wherein the maximum permissible for underground water is 5 μg.L-1. This is a worrying factor, since underground water makes up 70% of the city of Natal?s water supply / The retail fuel stations are partially or potentially polluters and generators of environmental accidents, potentially causing contamination of underground and surface water bodies, soil and air. Leaks in fuel retail stations? underground storage systems are often detected in Brazil and around the world. Monoaromatic hydrocarbons, BTEX (benzene, toluene, ethylbenzene and xylenes) and polycyclic aromatic hydrocarbons (PAHs) are an indication of the presence of contamination due to its high toxicity. This paper presents a case study of contamination in a Fuel Retail Station by petroleum derivative products in the city of Natal. For identification and quantification of the hydrocarbons, EPA analytical methods were used. The values of benzene quantified by EPA method 8021b CG-PID/FID, ranged from 1.164 to 4.503 mg.Kg-1 in soil samples, and from 12.10 to 27,639 μg.L-1 in underground water samples. Among the PAHs, naphthalene and anthracene showed the most significant results in soil samples, 0.420 to 15.46 mg.Kg-1 and 0.110 to 0,970 mg.Kg-1, respectively. In underground water samples, the results for Naphthalene varied between 0.759 and 614.7 μg.L-1. PAHs were quantified by EPA Method 8270 for GCMS. All of the results for the chemical analysis were compared with the values for the CONAMA 420/2009 resolution. The results for benzene (27,639 μg.L-1) showed levels highly above the recommended by the CONAMA 420 resolution, wherein the maximum permissible for underground water is 5 μg.L-1. This is a worrying factor, since underground water makes up 70% of the city of Natal?s water supply
7

Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veis / Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veis

Coelho, Eduardo Philipp Medeiros 31 January 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:52Z (GMT). No. of bitstreams: 1 EduardoPMC_DISSERT.pdf: 2258770 bytes, checksum: b0f9f75ce68f7e376f8b9edab280c699 (MD5) Previous issue date: 2011-01-31 / Today a major responsibility for the contamination of soil and groundwater and surface water are establishments known as gas stations of fuel which has attracted increasing attention from both the general population as the state agencies of environmental control due to leaks in storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other services, like oil changes and car wash are also causes for concern in this type of establishment. These leaks can cause or waste produced, and the contamination of aquifers, serious health problems and public safety, since most of these stations located in urban areas. Based on this, the work was to evaluate soil contamination of a particular service station and fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni, Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as optical emission spectrometry with inductively coupled plasma source (ICP OES), Total Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the soil through particle size analysis. Samples were taken in 21 georeferenced points and collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine sand to medium sand. The other study sites ranged from fine sand to medium sand, except the point P8 showed that only the type size medium sand and P19, indicating a particle size of the coarse type. The small correlation of organic matter with the elements studied in this work suggests that these are not of anthropogenic origin but geochemical support / Hoje um dos grandes respons?veis pela contamina??o do solo e ?guas subterr?neas e superficiais s?o os estabelecimentos conhecidos como postos de revenda de combust?veis que vem merecendo cada vez mais aten??o tanto da popula??o em geral como dos ?rg?os estaduais de controle ambiental devido a vazamentos em tanques de armazenamento, e principalmente ao rompimento da tubula??o de bombeamento e corros?o dos tanques. Outros servi?os como, troca de ?leo e lavagem de autom?veis tamb?m s?o motivos de preocupa??o neste tipo de estabelecimento. Estes vazamentos ou residuais produzidos podem causar, al?m da contamina??o de aq??feros, graves problemas de sa?de e de seguran?a p?blica, visto que a maioria destes postos localiza-se em ?reas urbanas. Baseado nisto, o trabalho realizado teve como objetivo avaliar a contamina??o do solo de um determinado posto de servi?os e revenda de combust?veis na Cidade de Natal, RN, por meio da quantifica??o de metais pesados como Cd, Cu, Cr, Ni, Pb, Zn, do teor de carbono org?nico total (COT) e da mat?ria org?nica utilizando t?cnicas distintas como espectrometria de emiss?o ?ptica com fonte de plasma indutivamente acoplado (ICP OES), analisador de Carbono Org?nico Total e an?lise gravim?trica respectivamente. E ainda caracterizar o solo por meio de an?lise granulom?trica. As amostragens foram realizadas em 21 pontos georeferenciados e coletadas no mesmo per?odo. Os solos amostrados nas esta??es de coleta P3, P5, P6, P10, P11, P12, P13, P14, P15, P17, P18 e P20 apresentaram as menores fra??es granulom?tricas variando de areia muito fina a areia m?dia. As demais esta??es de coleta variaram de areia fina a areia m?dia, exceto o ponto P8 que apresentou somente granulometria do tipo areia m?dia e P19, indicando granulometria do tipo grossa. A pequena correla??o da mat?ria org?nica com os elementos estudados neste trabalho sugere que estes n?o sejam de origem antr?pica e sim de suporte geoqu?mico

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