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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.
31

Programa de resposta à demanda baseado em preços aplicado a consumidores de baixa tensão

Ferraz, Bibiana Maitê Petry January 2016 (has links)
O incremento nos padrões de consumo de energia elétrica e o fácil acesso a diversas tecnologias eletroeletrônicas têm contribuído para a superação anual dos índices de consumo de eletricidade. Tendo em vista que esse insumo ainda não é economicamente armazenável em larga escala, se faz necessário manter o equilíbrio em tempo real entre a oferta/demanda mais perdas. Entretanto, a maioria dos consumidores brasileiros atendidos em baixa tensão paga tarifas baseadas nos custos médios, os quais ocultam os efeitos da alta concentração de consumo de eletricidade em determinados horários do dia. Nesse contexto, o presente estudo analisa o impacto que Programas de Resposta à Demanda (PRD), baseado em tarifas com diferenciação horária, exercem sobre o desempenho dos sistemas de distribuição. A metodologia proposta utiliza o conceito de elasticidade-preço da demanda de energia elétrica, por meio de uma abordagem matricial e permite representar diferentes tipos de consumidores. A partir de uma análise de sensibilidade dos estudos de casos, verificou-se a influência dos parâmetros que compõem as equações do PRD proposto. Para avaliar o desempenho do modelo, foram feitos estudos numéricos usando uma versão modificada do sistema teste IEEE de 34 nós. A análise de sensibilidade entre os estudos de caso apresentou uma avaliação do percentual de adesão dos consumidores, bem como o comportamento das perdas ativas mensais e do perfil de tensão. Os resultados obtidos no presente estudo evidenciam a validade da abordagem proposta, a partir de uma formulação simplificada, além de demonstrar a potencial aplicabilidade a casos reais. / Power consumption behavior increase and easy access to electroelectronics technologies had contributed to annual power consumption rates surpass. As there is not yet an economically sustainable way to store electric power it is necessary to maintain the balance between offer and power demand (considering losses). Brazilian customers majority supplied in low voltage are charged by its mean power consumption masking peak consumption in certain periods of the day. Within this reality the present work analysis the impact of Demand Response Programs (DRP) using Time-Of-Use tariff (TOU) over the power distribution system’s performance. The proposed methodology applies the concept of Price Elasticity demand and uses the representation of different consumers’ types in a matrix approach. The DRP parameters’ variation impact was checked using a sensitivity analysis. In order to evaluate the performance of the proposed model numerical studies were done using the IEEE 34 modified node test feeder. A sensitivity analysis among the case studies presents the customers adherence percentage and the monthly active power losses and voltage profile. The methodology's results besides supporting the proposal approach from a simplified formulation show the potential use on real cases.
32

Elasticidade de substituição: contribuição à análise de competitividade da indústria brasileira de celulose. / Elasticity of substitution: a contribution to the competitivity analysis of the Brazilian pulp industry.

Manhães, Giácoma Frasson 07 April 2011 (has links)
O setor brasileiro de celulose é um importante pilar da economia nacional. Só em 2010 a exportação de celulose trouxe para o País US$ 4,7 bilhões. Dada a sua importância, este setor já foi alvo de vários estudos de competitividade. No entanto, a mudança no cenário concorrencial global, marcada pela entrada de novos agentes, requer uma avaliação da posição competitiva do Brasil frente aos concorrentes emergentes. Neste contexto, este trabalho teve como objetivo identificar os novos players, descrever a dinâmica concorrencial nos principais mercados, propor ferramentas adequadas para avaliar os resultados dos países exportadores de celulose de fibra curta, e explicar as razões de liderança entre os países exportadores. A fim de mensurar os resultados dos países fornecedores, foi empregada uma função de subcusto translog restrita para obtenção da elasticidade de substituição entre as polpas de fibra curta dos principais países exportadores. Para essa análise foram considerados, separadamente, os mercados americano e chinês. Os resultados obtidos foram analisados levando-se em conta aspectos técnicos da polpas de fibra curta, com foco na morfologia das fibras, e também o histórico de formação dos setores de celulose no Brasil, na Indonésia (fornecedor emergente, principal fornecedor de celulose de fibra curta para a China) e no Canadá (fornecedor tradicional de celulose, principal concorrente do Brasil nos Estados Unidos). Foram também avaliadas as barreiras de mercado à polpa indonésia a partir do testemunho de funcionários e dirigentes de fábricas de papel na América do Norte, Europa e Ásia. As observações feitas sobre a organização setorial e tecnológica dos concorrentes foram comparadas aos modelos correntes de catch up tecnológico a fim de se identificar comportamentos que contribuam para a extensão da teoria nesta área. Os resultados do trabalho indicam que a competitividade brasileira no setor de celulose se apoia na produtividade florestal, resultado da acumulação de competências tecnológicas relacionadas ao eucalipto. Isso garante a competitividade brasileira frente aos concorrentes tradicionais. Frente à polpa indonésia, que vem acumulando competências tecnológicas relacionadas à acácia, a polpa brasileira é competitiva hoje. A manutenção da competitividade da polpa brasileira frente à indonésia no futuro dependerá da intensidade de investimentos em inovação feitos por ambos os países. / Pulp industry is a mainstay of Brazilian economy. In 2010, Brazilian pulp exports totaled US$ 4.7 billion. Given its importance, this industry has been the focus of several studies on competitiveness. However, the change in the competitive global scenario, marked by the entry of new players, requires an assessment of Brazil\'s competitive position towards emerging competitors. In this context, this work aimed to identify new players, to describe the dynamics of competition in key markets, to propose appropriate tools to assess the performance of hardwood pulp exporting countries, and explain the reasons for leadership among the exporting countries. In order to measure the supplier countries results, a restricted translog subcost function was applied to obtain the elasticity of substitution between hardwood pulp from the main exporters. This analysis was performed for both the U.S. and Chinese markets. Results were evaluated considering technical features of hardwood pulp, especially fiber morphology, and also a historic appraisal of pulp industry establishment in Brazil, Indonesia (emerging supplier, main hardwood pulp supplier to China) and in Canada (traditional pulp supplier, Brazil\'s main competitor in the U.S.). Market barriers to the entry of Indonesian pulp were also assessed based on the personal testimony of employees and executives of paper mills in North America, Europe and Asia. Observations on the competitors industry and technology setup were compared to current models of technological catch up in order to identify behaviors or patterns that contribute to the extension of the theory in this area. The results of this study indicate that the competitiveness of the Brazilian pulp industry is based on forest productivity, which result from the accumulation of technological capabilities related to eucalyptus. This ensures Brazilian competitiveness against traditional competitors. Compared to the Indonesian pulp industry, which has been accumulating technological capabilities related to acacia, the Brazilian pulp is currently competitive. Maintaining the competitiveness of Brazilian pulp against the Indonesian in the future will depend on the intensity of innovation investments made by both countries.
33

Mudanças nos usos da terra no Brasil entre 1995 e 2006 / Land use changes in Brazil between 1995 and 2006

Luiza Carneiro Mareti Valente 06 November 2012 (has links)
As mudanças nos usos da terra no Brasil têm sido muito discutidas atualmente, principalmente por causar desmatamento, degradação do solo, redução da biodiversidade e aumento da emissão de gases de efeito estufa, influenciando nas mudanças climáticas. Entretanto, a atividade agropecuária é importante para a economia brasileira por ser grande geradora de emprego e renda. Dessa forma, é necessário que o governo brasileiro, por meio de políticas agrícolas e ambientais, consiga regular a interação entre o meio ambiente e a produção agrícola de modo a gerar os maiores benefícios possíveis para a sociedade tanto do ponto de vista econômico quanto do ambiental. Para contribuir nessa discussão esse trabalho é composto por três artigos. O primeiro discutiu a evolução recente das políticas e instrumentos de políticas públicas que atuam diretamente nos usos das terras agrícolas privadas: o Código Florestal Brasileiro, o Importo Territorial Rural além de políticas públicas mais recentes de pagamentos por serviços ambientais. Concluiuse que a pouca fiscalização prejudica a efetividade das políticas e, consequentemente, não induz ao comportamento esperado dos produtores. Entretanto, as políticas de pagamentos por serviços ambientais e a criação da cota de reserva ambiental tem grande potencial de influenciar os produtores em direção a atitudes mais responsáveis ambientalmente. O segundo artigo discutiu as mudanças no uso do solo e a evolução da produção agrícola abordando o Brasil e cada um dos biomas brasileiros separadamente. Observou-se que as lavouras tem se expandido sobre as áreas de pastagens e florestas. Assim, é necessário aumentar a fiscalização e controle das atividades agrícolas de modo a direcionar a pressão para as áreas de pastagens, estimulando a intensificação da bovinocultura. Além disso, é necessário o desenvolvimento de alternativas específicas para a região da caatinga, visando melhorar a produção agrícola desse bioma. O terceiro e último artigo estudou os principais determinantes do uso do solo no Brasil e nos biomas. Identificou-se grande influência da mecanização em todos os usos de solo e, para o caso da cana-de-açúcar, da presença de usinas no município. Ainda, no modelo para o Brasil, as dummies de biomas e as variáveis de altitude, precipitação e temperatura apresentaram influencia significativa. Ainda, as elasticidades área preço calculadas identificaram pouca influência dos preços sobre as áreas plantadas, principalmente relacionados às áreas de pastagens e florestas. Concluiu-se que os resultados do modelo estimado podem não refletir adequadamente as pressões para as alterações nos usos da terra e diversas melhorias são sugeridas. Finalmente, conclui-se que é necessária uma abordagem interdisciplinar para compreender e abordar adequadamente as mudanças do uso do solo no Brasil. / Changes in the land use in Brazil have been much discussed today, mainly for causing deforestation, soil degradation, decrease of biodiversity and increased emission of greenhouse gases, influencing the climate change. The agricultural activity, however, is important for the Brazilian economy as it is a great generator of employment and income. Thus, it is necessary that the Brazilian government, through agricultural and environmental policies, gets to regulate the interaction between the environment and agricultural production in order to generate the greatest possible benefits to society not only from the economic but also from the environmental point of view. This work consists of three articles to contribute to this discussion. The first discussed the recent development of the public policies and policy instruments that act directly on the uses of private agricultural land: the Brazilian Forestry Code, the Rural Land Tax besides the latest public policies on payments for environmental services. It was concluded that little oversight undermines the effectiveness of policies and therefore does not lead to the expected behavior of producers. However, the policies of payments for environmental services and the creation of environmental reserve quota has great potential to influence attitudes towards producing more environmental responsibility. The second article discussed the changes in land use and the development of agricultural production in Brazil and each of the Brazilian biomes separately. It was observed that crops have expanded over the grazing areas and forests. Thus, it is necessary to increase the supervision and control of agricultural activities in order to direct the pressure to grazing areas, encouraging intensification of livestock production. Moreover, it is necessary to develop specific alternatives to the caatinga region, to improve agricultural production in this biome. The third and final article studied the main determinants of land use in Brazil and its biomes. A major influence of mechanization was identified in all land use and, for the sugar cane, the presence of industrial plants in the county also influenced its area. Still, in the model for Brazil, the dummies of biomes and the variables of altitude, rainfall and temperature had significant influence. Still, the area price elasticities calculated identified little influence of the prices on the areas planted, mainly related to grazing areas and forests. It was concluded that the results of the estimated model may not accurately reflect the pressures for changes in land uses and several improvements are suggested. Finally, it is concluded that an interdisciplinary approach is required to understand and properly deal with the changes of land use in Brazil.
34

The Making of the Swedish Life Insurance Market 1855-1914

Eriksson, Liselotte January 2008 (has links)
This licentiate thesis examines the development of the life insurance industry during the period 1855-1914. The aim with the study is to recognise dimensions not frequently addressed by previous research on the insurance industry, namely the impact of social dimensions, including the implicit and explicit economic importance of social movements and the diffusion of knowledge in society at large for the development of the life insurance industry. The study shows that income and price had limited importance in explaining the demand for life insurance before the 20th century and that this can be attributed to a lack of sufficient knowledge regarding financial issues and to a far too high access cost in acquiring a life insurance for a large part of society. The development of the life insurance industry must therefore be understood through improved knowledge both on the part of the life insurance companies and on part of the consumers. The licentiate further shows how diffusion of knowledge throughout society also was due to a diffusion of democratic ideas and the rise of social movements, movements that life insurance actors were a part of. These actions helped open up the financial market for the masses and probably also strengthened the trust towards the industry. It is however hard to dismiss the life insurance actors’ engagement in women’s movement as a cover-up for other disguised motives not so honourable, while a direct economic gain for the life insurance industry is hard to establish.
35

Otimização da cobrança pelo uso da água para a gestão da demanda hídrica em cenários de longo prazo / Water pricing optimization for demand management in long-term scenarios

Silva, Fernando Simão e 06 November 2009 (has links)
A cobrança pelo uso da água é um instrumento de gestão de recursos hídricos previsto na Lei 9433/97, dentre outros objetivos, para incentivar o uso racional da água. Porém, os estudos e simulações feitos tratam a cobrança apenas como instrumento de arrecadação. Este trabalho tem o objetivo de propor preços unitários para a água com base na necessidade de redução da demanda futura na bacia do Tietê-Jacaré. Para isso, apoia-se em cenários de demanda e oferta hídricas para os anos de 2010, 2025 e 2050 elaborados por Macêdo (2005), cujas estimativas de demanda são também melhoradas neste trabalho. Para modelar a relação entre cobrança e demanda, são usados modelos econométricos adaptados de outras bacias, especialmente a do Paraíba do Sul. Tudo isso serve de base para um algoritmo de otimização, usado para propor mudanças na política de cobrança, levando ao atendimento de metas como a redução da escassez dos recursos hídricos no futuro. / Water pricing is a water resources management tool according to brazilian law 9433/97 and it serves the purpose of giving incentive to rational use of water, among others. However, studies and simulations treat pricing as a revenue generator mechanism only. This dissertation aims to propose water unit prices based on demand reduction needs in the Tietê-Jacaré basin, Brazil. In order to do it, it uses demand and supply scenarios for 2010, 2025 and 2050 developed by Macêdo (2005), whose estimates are also slightly improved here. Econometric models are used to model the relationship between pricing and demand and they are adapted from other basins, mainly the Paraíba do Sul one. All this serves as base for an optimization algorithm, which is used to propose changes in water pricing policy, leading to the attainment of water stress reduction goals in the future.
36

DEVELOPMENT OF A TRANSLATIONAL MODEL OF CO-USE OF ALCOHOL AND NICOTINE FOR TESTING POTENTIAL PHARMACOTHERAPIES

Maggio, Sarah Elizabeth 01 January 2019 (has links)
Co-users of alcohol and nicotine are the largest group of polysubstance users worldwide. Although pharmacotherapies are available for alcohol (EtOH) or tobacco use disorders individually, it may be possible to develop a single pharmacotherapy to treat heavy drinking tobacco smokers through capitalizing on the commonalities in their mechanisms of action. Towards this goal, several models of concurrent access to EtOH and nicotine were explored as potential preclinical models of co-use using female alcohol-preferring (P) rats. Additionally, potential pharmacotherapeutics for the treatment of EtOH and nicotine co-use disorder were tested using different variations of our model. Treatments tested included (1) varenicline, a nicotinic acetylcholine receptor (nAChR) partial agonist with high affinity for the α4β2* subtype; (2) r-bPiDI, a subtype-selective antagonist at α6β2* nAChRs; (3) (R)-modafinil, an atypical inhibitor of the dopamine transporter (DAT); and (4) naltrexone, a clinically available µ-opioid receptor antagonist used to treat alcohol use disorder (AUD). Results from the current dissertation show success in developing a translational animal model in female P rats for co-use of EtOH and nicotine under which pharmacologically relevant levels of both EtOH consumption and nicotine intake are achieved. Additionally, our model was successfully used in testing potential pharmacotherapeutics for the treatment of EtOH and nicotine co-use disorder. Although none of the drugs tested were effective as a monotherapy, results from testing the known smoking cessation agent varenicline and the known AUD treatment naltrexone indicate that our model is effective for selectively measuring changes in EtOH and nicotine intake separately, which suggests the beneficial utility of this model for future treatment research. Furthermore, by applying behavioral economic principles to our findings, we found that EtOH acts as an economic substitute for nicotine. Additionally, our behavioral economic analyses revealed that when the cost of nicotine is changed via response requirements vs dose per infusion, there are differences in the elasticity of demand for concurrently available EtOH and nicotine. Finally, the relatively flat consumption curve for EtOH following varenicline pretreatment suggests that pretreatment with varenicline acts to disrupt the relationship between EtOH and nicotine such that EtOH no longer acts as an economic substitute for nicotine.
37

The Making of the Swedish Life Insurance Market 1855-1914

Eriksson, Liselotte January 2008 (has links)
<p>This licentiate thesis examines the development of the life insurance industry during the period 1855-1914. The aim with the study is to recognise dimensions not frequently addressed by previous research on the insurance industry, namely the impact of social dimensions, including the implicit and explicit economic importance of social movements and the diffusion of knowledge in society at large for the development of the life insurance industry. The study shows that income and price had limited importance in explaining the demand for life insurance before the 20th century and that this can be attributed to a lack of sufficient knowledge regarding financial issues and to a far too high access cost in acquiring a life insurance for a large part of society. The development of the life insurance industry must therefore be understood through improved knowledge both on the part of the life insurance companies and on part of the consumers. The licentiate further shows how diffusion of knowledge throughout society also was due to a diffusion of democratic ideas and the rise of social movements, movements that life insurance actors were a part of. These actions helped open up the financial market for the masses and probably also strengthened the trust towards the industry. It is however hard to dismiss the life insurance actors’ engagement in women’s movement as a cover-up for other disguised motives not so honourable, while a direct economic gain for the life insurance industry is hard to establish.</p>
38

The Great Indian Affordable Housing Crisis: Determining the Price and Income Elasticities of Urban Rental Housing Demand

Maniar, Megha 01 January 2012 (has links)
The Indian urban rental market is complex and yet ever-changing, with the ups and downs of housing demand playing a fundamental role in the affordability and stability of the market. This paper determines the income and price elasticities of demand using the demand function and Slutsky equation, respectively, for the urban rental market in order to help craft suitable national housing policy. Through this analysis, it is determined that the urban rental price elasticity of demand is -0.93 and the income elasticity is 0.81, suggesting that rental price subsidies and private income taxes are the most effective policy measures to ensure affordability in urban India.
39

Efterfrågans priselasticitet på cigaretter på kort- och lång sikt : En studie av effekten på cigarettskatten och cigarettpriset i Sverige mellan år 1996-2012

Jesper, Hamrén, Anna, Viktorsson January 2014 (has links)
The study examines the price elasticity of demand for cigarettes in the short- and long run in Sweden. The time period for the study is 17 years and covers the years 1996-2012. The results of the study shows that the price elasticity of demand for cigarettes in the long run is higher than in the short run for the Swedish consumers, which is in line with previous studies in the area. The fact that the price elasticity of demand for cigarettes is higher in the long run, indicates that the substitution effect has a significant impact on the price elasticity of demand for cigarettes in the long run. The study was conducted in two parts where the authors investigated the effect of cigarette tax on cigarette prices and in addition the cigarette prices impact on the demand for cigarettes in Sweden. The combined result of the study demonstrates that increasing the cigarette tax by 10 per cent means that the demand for cigarettes is reduced by 5 per cent, while government revenues from the cigarette tax will increase by 4.5 per cent. The result in this paper shows why the state's incentive to raise the cigarette tax is twofold, since a tax increase will generate health benefits through reduced consumption and generate increased revenues to the state. These incentives are also shown to have a greater impact in the long term. / Studien undersöker efterfrågans priselasticitet på cigaretter på kort- och lång sikt i Sverige. Tidsperioden för undersökningen är 17 år och omfattar åren 1996-2012. Studiens resultat visar att efterfrågans priselasticitet på lång sikt är högre än på kort sikt för de Svenska konsumenterna, vilket ligger i linje med tidigare studier inom ämnet. Det faktum att priselasticiteten för cigaretter är högre på lång sikt indikerar på att substitutionseffekten har betydande effekt för efterfrågans priselasticitet på cigaretter på lång sikt. Studien har genomförts i två delar där författarna undersökt cigarettskattens effekt på cigarettpriset och i sin tur cigarettprisets effekt på efterfrågan på cigaretter i Sverige. Det kombinerade resultatet i studien påvisar att en ökning av cigarettskatten med 10 procent medför att efterfrågan på cigaretter minskar med 5 procent, samtidigt som statens intäkter från cigarettskatten ökar med 4,5 procent. Resultatet i denna uppsats visar därför att statens incitament till att höja cigarettskatten är tvådelad, då en skatteökning genererar hälsovinster genom minskad konsumtion samt genererar ökade intäkter till staten och att dessa incitament har en större påverkan på lång sikt.
40

Wine investment, pricing and substitutes

Fogarty, James January 2006 (has links)
[Truncated abstract] This thesis consists of six chapters, and the main research contributions are contained in chapters two through five inclusive. The topics addressed in each chapter are distinct, but related, and the specific contributions to knowledge made by the different chapters are related to: (i) understanding more fully the nature of the demand for alcohol; (ii) explaining the relationship between reputation characteristics and consumers’ willingness to pay for wine; (iii) estimating the rate of return to Australian wine; and (iv) using financial analysis to reveal the risk diversification benefits available by including wine in an investment portfolio. The details of each contribution are briefly outlined below. Chapter 2 discusses the nature of the demand for alcohol. The demand for alcoholic beverages is an area much studied, and there are numerous studies estimating the own-price elasticity of alcoholic beverages. A review of relevant published studies indicates reported: beer own-price elasticity estimates range from -.02 to -3.00, with a mean estimate value of -.46, and standard deviation of -.41 (n = 139); wine own-price elasticity estimates range from -.05 to -3.00, with a mean estimate value of -.72, and standard deviation of .53 (n = 140); and spirits own-price elasticity estimates range from -.01 to -2.18, with a mean estimate value of -.74, and standard deviation of .47 (n = 136). Chapter 2 contributes to understanding the demand for alcohol, not by adding yet another set of elasticity estimates to an already substantial literature, but by providing a framework through which all known own-price elasticity estimates can be understood. Specifically, a meta-regression framework is employed to study previously published own-price elasticity estimates. This framework allows the effect of model design attributes to be isolated, and the underlying trend in consumer responses to price changes to be identified.

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