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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.
111

The UK electricity market : its evolution, wholesale prices and challenge of wind energy

Cui, Cathy Xin January 2010 (has links)
This thesis addresses the problems associated with security of the electricity supply in the UK. The British electricity supply industry has experienced a significant structural change. Competition has been brought into the electricity industry and a single wholesale electricity market of Great Britain has been established. The evolution of the British electricity market raises new challenges, such as improving the liquidity of wholesale markets and developing clean energy. The wholesale electricity prices are less transparent and trading arrangements are very complex in the British electricity market. In this thesis a fundamental model, called a stack model, has been developed in order to forecast wholesale electricity prices. The objective of the stack model is to identify the marginal cost of power output based on the fuel prices, carbon prices, and availability of power plants. The stack model provides a reasonable marginal cost curve for the industry which can be used as an indicator for the wholesale electricity price. In addition, the government's targets for climate change and renewable energy bring new opportunities for wind energy. Under the large wind energy penetration scenario the security of the energy supply will be essential. We have modelled the correlations between wind speed data for a set of wind farms. The correlation can be used to measure the portfolio risk of the wind farms. Electricity companies should build their portfolio of wind farms with low or negative correlations in order to hedge the risk from the intermittency of wind. We found that the VAR(1) model is superior to other statistic models for modelling correlations between wind speeds of a wind farm portfolio.
112

Modeling, control, and optimization of combined heat and power plants

Kim, Jong Suk 25 June 2014 (has links)
Combined heat and power (CHP) is a technology that decreases total fuel consumption and related greenhouse gas emissions by producing both electricity and useful thermal energy from a single energy source. In the industrial and commercial sectors, a typical CHP site relies upon the electricity distribution network for significant periods, i.e., for purchasing power from the grid during periods of high demand or when off-peak electricity tariffs are available. On the other hand, in some cases, a CHP plant is allowed to sell surplus power to the grid during on-peak hours when electricity prices are highest while all operating constraints and local demands are satisfied. Therefore, if the plant is connected with the external grid and allowed to participate in open energy markets in the future, it could yield significant economic benefits by selling/buying power depending on market conditions. This is achieved by solving the power system generation scheduling problem using mathematical programming. In this work, we present the application of mixed-integer nonlinear programming (MINLP) approach for scheduling of a CHP plant in the day-ahead wholesale energy markets. This work employs first principles models to describe the nonlinear dynamics of a CHP plant and its individual components (gas and steam turbines, heat recovery steam generators, and auxiliary boilers). The MINLP framework includes practical constraints such as minimum/maximum power output and steam flow restrictions, minimum up/down times, start-up and shut-down procedures, and fuel limits. We provide case studies involving the Hal C. Weaver power plant complex at the University of Texas at Austin to demonstrate this methodology. The results show that the optimized operating strategies can yield substantial net incomes from electricity sales and purchases. This work also highlights the application of a nonlinear model predictive control scheme to a heavy-duty gas turbine power plant for frequency and temperature control. This scheme is compared to a classical PID/logic based control scheme and is found to provide superior output responses with smaller settling times and less oscillatory behavior in response to disturbances in electric loads. / text
113

Three Papers on the Effects of Competition in Engery Markets

Choi, Wai Hong January 2013 (has links)
This thesis comprises three papers examining the impact of competitive pricing or competition on participants in energy markets. The scope of each paper is narrow but focused, dealing with one particular aspect of competition in each market under study. It is hoped that results from these three studies could provide valuable policy lessons to public policy makers in their task to create or maintain competition in different energy markets, so as to improve efficiencies in these markets. The first and second papers examine the load shifting behavior of industrial customers in Ontario under real time pricing (RTP). Using Hourly Ontario Energy Price (HOEP) data from 2005 to 2008 and industry-level consumption data from all industrial customers directly connected to the transmission grid, the first paper adopts a Generalized Leontief specification to obtain elasticities of substitution estimates for various industry groups, while the second paper adopts a specification derived from standard consumer theory to obtain price elasticity estimates. The findings of both papers confirm that in some industries, industrial customers who are direct participants of the wholesale market tend to shift consumption from peak to off-peak periods in order to take advantage of lower off-peak prices. Furthermore, in the first paper, a demand model is estimated and there is evidence that the marginal effect of hourly load on hourly price during peak periods is larger than the marginal effect during off-peak periods. An important policy implication from the results of these papers is that while RTP is currently limited to industrial customers, it does have positive spillover effects on all consumers. The third paper uses a unique panel dataset of all retail gasoline stations across five Canadian cities from late-2006 to mid-2007 to examine the effect of local competition on market shares and sales of individual stations. The base empirical specification includes explanatory variables representing the number of same brand stations and the number of different brand stations within a 3km radius to identify brand affiliation effect. It is found that the number of local competitors is negatively correlated with market share and sales. More interestingly, a same brand competitor has a larger marginal impact on market share and sales than a competitor of a different brand. These findings suggest that additional local competition leads to cannibalization of market share among existing stations, rather than create new demand. Another implication is that relying only on the number of different brands operating within a geographic market could understate the competition intensity in the local market.
114

Economics of intermittent renewable energy sources : four essays on large-scale integration into European power systems

Henriot, Arthur 05 May 2014 (has links) (PDF)
This thesis centres on issues of economic efficiency originating from the large-scale development of intermittent renewable energy sources (RES) in Europe. The flexible resources that are necessary to cope with their specificities (variability, low-predictability, site specificity) are already known, but adequate signals are required to foster efficient operation and investment in these resources. A first question is to what extent intermittent RES can remain out of the market at times when they are the main driver of investment and operation in power systems. A second question is whether the current market design is adapted to their specificities. These two questions are tackled in four distinct contributions.The first chapter is a critical literature review. This analysis introduces and confronts two (often implicit) paradigms for RES integration. It then identifies and discusses a set of evolutions required to develop a market design adapted to the large-scale development of RES, such as new definitions of the products exchanged and reorganisation of the sequence of electricity markets.In the second chapter, an analytical model is used to assess the potential of intraday markets as a flexibility provider to intermittent RES with low production predictability. This study highlights and demonstrates how the potential of intraday markets is heavily dependent on the evolution of the forecast errors.The third chapter focuses on the benefits of curtailing the production by intermittent RES, as a tool to smooth out their variability and reduce overall generation costs. Another analytical model is employed to anatomize the relationship between these benefits and a set of pivotal parameters. Special attention is also paid to the allocation of these benefits between the different stakeholders.In the fourth chapter, a numerical simulation is used to evaluate the ability of the European transmission system operators to tackle the investment wave required in order to manage the production of intermittent RES. Alternative financing strategies are then assessed. The findings reveal that under the current trend of tariffs, the volumes of investment forecasted will be highly challenging for transmission system operators.
115

Changes in the market structure of food retailing, 1940-1957

Garoian, Leon. January 1959 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 368-374).
116

As articulações escalares da indústria de confecções em Cianorte - Pr /

Gonçalves, Márcio Teixeira. January 2005 (has links)
Orientador: Raul Borges Guimarães / Banca: Alice Yatiyo Asari. / Banca: Maria Encarnação Beltrão Sposito / Resumo: Realizamos neste trabalho um estudo centrado na análise do desenvolvimento da indústria do ramo de confecções de Cianorte, PR, tomando-o como elemento indutor da produção e articulação entre as escalas geográficas. Cianorte caracteriza-se por apresentar um forte processo de industrialização pautado no ramo de confecções, sobretudo a partir de meados da década de 1980, como saída para enfrentar a crise econômica de uma economia agrícola que predominava até então. Compreender como se deu esse processo de transformação funcional em Cianorte constitui uma das questões motivadoras deste trabalho. Neste sentido, analisamos o processo de transformação da organização industrial da área a ser pesquisada, resgatando como se deu sua inserção no sistema de acumulação flexível, além de discutir o processo de criação e articulação entre as escalas geográficas, tomando a indústria de confecções de Cianorte como elemento de articulação entre o espaço local e o global. As transformações no espaço urbano de Cianorte que se vinculam a este processo recente de especialização industrial no ramo de confecções também constitui foco de análises neste trabalho. Partindo da idéia de "síntese de múltiplas escalas", procuramos valorizar o papel exercido pelas relações sociais de cooperação/competição entre os atores privilegiados naquela realidade local, a fim de verificar as implicações que vinculam a indústria de confecções como processo econômico e suas conseqüências espaciais em Cianorte. Neste caso, a criação do slogan "Cianorte: Capital do Vestuário",...(Resumo completo, clicar acesso eletrônico abaixo). / Abstract: We carried out in this work a study focused on the analysis of the clothing industry development in Cianorte, PR, taking it as an inductor of production and articulation among geographic scales. Cianorte has a strong industrialisation process based on the clothing field, especially since the 1980s, as a way to face the economic crises of an agricultural economy which was predominant in that time. To understand how this functional transformation process happened in Cianorte is one of the questions that motivated the development of this work. Therefore, we analysed the transformation process of the industrial organisation in the area to be researched, bringing back how its insertion in the system of flexible accumulation happened, besides discussing the creation and articulation process among the geographic scales, taking the clothing industry of Cianorte as an element of articulation between the local and the global space. The transformations in the urban space of Cianorte which have been linked to this recent process of industrial specialisation in the clothing field is also a focus for analysis in this work. From the idea of "synthesis of multiple scales", we try to value the role taken by the social relations of cooperation/ competition among the privileged actors in that local reality, so as to check the implications that link the clothing industry as an economic process and its spatial consequences in Cianorte. In this case, the creation of the slogan "Cianorte: capital of clothing", of Expovest and wholesale shopping centres, has to be taken as a result of a struggle of interests...(Complete abstract, click electronic address below). / Mestre
117

A gestão da demanda em cadeias de suprimentos: um estudo no setor atacadista distribuidor de produtos de mercearia básica

Melo, Daniela de Castro 29 March 2011 (has links)
Made available in DSpace on 2016-06-02T19:50:10Z (GMT). No. of bitstreams: 1 3520.pdf: 2416853 bytes, checksum: 440e192e9b7986c17526e5ea7efd70e1 (MD5) Previous issue date: 2011-03-29 / Financiadora de Estudos e Projetos / Demand management is an emerging topic in supply chain management. It is focused on a fast and adequate integration of supplier needs in order to balance and strategically align demand with operational capability in the supply chain. The lack of demand alignment deals with problems in supply chain, which leads to inefficient customer service, poor stock rotation, and high obsolescence rate aggravated by the wide diversity of products. The objective of this thesis was to develop a framework for demand management in the supply chain of grocery products considering the dyadic relationship between the supplier and the wholesale. The research revealed that the framework can be divided into 1) determining factors for the implementation of demand management between the wholesale and supplier and 2) the implementation process of the demand management between these firms. The determining factors involve strategic intent; internal alignment of the strategic policies; supplier segmentation; customer segmentation; reward, expertise, legitimate power and collaborative supply chain orientation. The implementation of this process can be divided into three phases: 1) joint alignment of strategic policies, 2) formulation of business plan and 3) implementation and monitoring of the business plan. Moreover, this process has four elements that permeate it: top management involvement, inter and intra-firm interactions, challenges and benefits of demand management. The benefits reflect on a reduction of the effect of the demand amplification, profitability by improving efficiency and effectiveness, as well as knowledge sharing and learning. / A gestão da demanda é um tema emergente no campo de conhecimento da gestão da cadeia de suprimentos. O que se busca com a gestão da demanda é a rápida e adequada integração das necessidades originadas do mercado na direção dos fornecedores, de modo a balancear e alinhar estrategicamente a demanda com a capacidade operacional ao longo da cadeia de suprimentos. Esse alinhamento da demanda na cadeia de suprimentos enfrenta dificuldades provocando ineficiência no atendimento a clientes, redução do giro de estoque e alto índice de obsolescência agravada pela grande diversidade de produtos. O objetivo desta tese foi desenvolver um modelo para a gestão da demanda na cadeia de suprimentos de produtos de mercearia básica considerando os elos fornecedor e atacadista distribuidor. Para tal, realizou-se uma pesquisa qualitativa por meio da revisão sistemática da literatura e de estudo de caso na empresa Martins e em nove fornecedores desta empresa. A pesquisa revelou que o modelo de gestão da demanda pode ser dividido em 1) fatores condicionantes para a implantação da gestão da demanda entre os elos atacadista distribuidor e fornecedor e 2) processo de implantação da gestão da demanda entre estes elos. Os fatores condicionantes envolvem intenção estratégica; alinhamento interno das diretrizes estratégicas; segmentação de fornecedores; segmentação de clientes; poder de recompensa, de especialização e legítimo; orientação para a colaboração na cadeia de suprimentos. O processo de implantação pode ser dividido em três fases: 1) alinhamento conjunto das diretrizes estratégicas das empresas; 2) formulação do plano de negócios e 3) execução e acompanhamento do plano de negócios. Além disso, este processo apresenta quatro elementos que o permeiam: envolvimento da alta gerência, interações inter e intraempresas, desafios e benefícios da gestão da demanda. Estes benefícios compreendem a diminuição do efeito da amplificação da demanda, o aumento da rentabilidade por meio da melhoria da eficiência e eficácia, como também o compartilhamento de conhecimento e aprendizado pelas empresas.
118

Valor de empresas e medidas de desempenho econômico: um estudo em empresas atacadistas brasileiras

Miranda, Gilberto José 28 February 2005 (has links)
Universidade Federal de Uberlândia / The present study has as main objective to verify which the concepts and methodologies of measurement of economical acting have been used in Brazilian wholesale companies, that can contribute to the adoption of models based in the value. Considering that the approaches of the Residual Economical Result (RER), Discounted Cash flow (FCD) and Integral Economical Result (REI - GECON) they are methodologies that have potential to contribute with the Value Based Management (VBM), it was looked for to verify if the pertinent concepts to these methodologies have been implemented in practice. For so much, an empiric research was accomplished in 101 wholesale companies and Brazilian distributors. It was verified that the most generic concepts on the approach of the value are quite disseminated in those companies. However, when it breaks for the pragmatic use, this reality changes, because it was not identified a group of companies that used the approach of the value in the fullness. The one that it identified was the existence of companies with some appropriate instruments, and another using in a partial way the concepts requested on the part of the Value Based Management. It seems there to be an attempt of the companies in applying what is possible in agreement with the reality of each one of them. However, of course the traditional measures of acting (revenue, gross and operational margin, profit and return on the investment) still prevail in the researched atmosphere. / O presente estudo tem como objetivo principal verificar quais os conceitos e metodologias de mensuração de desempenho econômico têm sido utilizados em empresas atacadistas brasileiras, que possam contribuir para a adoção de modelos baseados no valor. Levando-se em consideração que as abordagens do Resultado Econômico Residual (RER), Fluxo de Caixa Descontado (FCD) e Resultado Econômico Integral (REI GECON) são metodologias que têm potencial para contribuir com a Gestão Baseada em Valor (GBV), buscou-se verificar se os conceitos pertinentes a estas metodologias têm sido implementados na prática. Para tanto, foi realizada uma pesquisa empírica em 101 empresas atacadistas e distribuidores brasileiros. Verificou-se que os conceitos mais genéricos sobre a abordagem do valor se encontram bastante disseminados nessas empresas. No entanto, quando se parte para o uso pragmático, esta realidade muda, pois não foi identificado um grupo de empresas que utilizasse a abordagem do valor em sua plenitude. O que se identificou foi a existência de empresas com alguns instrumentos adequados, e outras utilizando de forma parcial os conceitos requeridos por parte da Gestão Baseada em Valor. Parece haver uma tentativa das empresas em aplicar aquilo que é possível de acordo com a realidade de cada uma delas. No entanto, ficou claro que as medidas tradicionais de desempenho(faturamento, margem bruta e operacional, lucro e retorno sobre o investimento) ainda prevalecem no ambiente pesquisado. / Mestre em Administração
119

The Global Expansion of Transnational Retailers: A Case Study of the Localization Strategy of Costco in Taiwan

Yeh, YunLung 12 1900 (has links)
This research focuses on the global expansion of the transnational retail industry. Globalization is a phenomenon experienced by many industries in the present global economy. The global production network (GPN) framework can be used to explain and interpret the phenomenon of transnational firms' adaptation strategies. Due to market saturation in their home countries, retailers began to expand into East Asia in the 1980s. However, cultural differences and legislative limitations created barriers and restrictions for the transnational retailers making this transition. How do firms overcome these challenges? Through a case study of Costco in Taiwan, this research investigates the ways in which retailers adapt their strategies with regard to three concerns: site decisions, product mix selection, and supply network consolidation. The results shows that Costco opted for a strategy of lesser localization in all three domains. This research provides evidence to support this characterization along with examples of Costco's localization strategies via a case study and focuses on the issue of the balance between localization and standardization in the GPN framework.
120

Marketingový audit vybrané společnosti / Marketing Audit of a Company

Ermolin, Daniil January 2021 (has links)
The master‘s thesis deals with marketing auditing of company Tungaloy Rus with a special focus on its employees’ satisfaction. The theoretical part of the thesis defines the meaning and importance of marketing audit, as well as the concept of employees’ satisfaction and modern approaches to its measurement. The analytical part of the thesis focuses on performing the marketing audit of company Tungaloy Rus and surveying the satisfaction of its employees. The proposal part of the thesis aims to making a set of recommendations based on the results of the marketing audit and the satisfaction research, which leads to improving the company's marketing activities.

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