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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.
71

Ekonomické aspekty využití energie z fotovoltaické elektrárny / Economic aspects use of energy of photovoltaic plant

Cerman, Marek January 2013 (has links)
The major topic of this master‘s thesis is to create a complex model of general photovoltaic power plant (PVP). First chapters are engaged in research of photovoltaic. Growth of globally installed power and analysis of situation in Czech Republic are described in this section. The spectrum of conditions is introduced, from current legislative framework up to local Sun radiation. The actual technologies and their advantages are depicted, especially rate of utilization of energy. Expected trends of future development of conversion efficiency are mentioned, with prediction of production costs of photovoltaic. In context with those aspects, the question of grid parity achievement arises. The own assembled model of photovoltaic power plant has been created in Microsoft Excel. The mathematical apparatus is described in a separate chapter, individually solving technical part, which main result – the amount of yearly generated electricity, is applied for economical calculation. Final results are the usual economic indicators, mainly: Net Present Value (NPV), Internal Rate of Return (IRR), Levelized Cost of Electricity (LCOE). There is series of aspects defined by user in the model which may impact the amount of produced electricity and economics of user’s project, such as use of loan, replacement of converters, operational costs etc. These aspects are frequently neglected by project sellers. In the end, intended photovoltaic power plants of 2.75 kWp and 28.98 kWp are simulated by the model in real conditions of 2013. Sensitivity of impact of both proposals to the aspects mentioned above has been analyzed. In the conclusion the achieved results are summarized and the key factors which determine the PVP’s economic efficiency are assessed.
72

Hodnocení ekonomické efektivnosti investičního záměru / Evaluation of Economic Efficiency of Investment Project

Danyśová, Ester January 2017 (has links)
The thesis focuses on determination of cash flow and evaluation of economic efficiency of the development project of the residential construction in Brno. The theoretical part deals with basic evaluation of economic efficiency of investment project including the most used indicators and gives insight into the developing activity including risks that companies must count with in such projects. The practical part deals with the particular project where cash flows are determined and its economic efficiency is evaluated.
73

Sports venues’ effect on social welfare : Cost-Benefit analysis of infrastructure investments within Lugnet area in Falun

Biedrzycki, Remigiusz January 2016 (has links)
Economic analysis and evaluation of sport events and sports infrastructure is a widely researched topic, especially when it comes to mega-sports events. As many of major and mega events require large amount of resources, governments and municipalities worldwide have to make decisions regarding support for the events. To determine whether and to what extent events should be subsidised with public resources, a thorough analysis of potential impacts of the event has to be conducted. Most of the studies within this field choose Economic Impact Analysis as a method, while many researchers point out a need for costbenefit analysis, as only a comprehensive analysis of costs and benefits for society can justify public subsidies for sport events and sports infrastructure. This paper presents a cost-benefit approach of sports venue evaluation. A cost-benefit analysis made in this paper, on the case of Swedish outdoor area of Lugnet, Falun, presents possible effects of sports infrastructure investments on social welfare. Analysis was aimed towards investments made prior to hosting 2015 FIS Nordic World Ski Championships in Falun. Presenting results for three alternative scenarios, this study compares different effects on social benefit. This research paper highlights areas that need to be investigated to ensure the better quality of the results, thus it can be beneficial for further studies of the topic. Results presented in this paper can also be beneficial for policy makers, as many of the potential welfare effects were described.
74

Производительность труда как фактор развития металлургической промышленности : магистерская диссертация / Labor productivity as the factor of metallurgical industry development

Бабаев, Э. Р., Babaev, E. R. January 2021 (has links)
Вопросы повышения экономической эффективности предприятий металлургической промышленности под влиянием различных факторов являются актуальными на современном этапе развития Российской экономики. В современной экономике важнейшим и определяющим фактором является повышение эффективности производства на основе увеличения производительности труда. Целью магистерской диссертации является развитие методических основ исследования влияния производительности труда на эффективность развития предприятий металлургической промышленности. В работе рассматриваются теоретические и прикладные аспекты анализа производительности труда и экономической эффективности в металлургическом производстве, а также и вопросы их взаимосвязи. В качестве источников информации использовались учебно-методическая и научно-исследовательская литература, официальные статистические данные и данные финансовой отчетности предприятий. В магистерской диссертации разработан методический подход к оценке влияния производительности труда на экономическую эффективность предприятий металлургической промышленности, измеряемую на основе показателя рентабельности активов. Методический подход предполагает получение комплексной экономико-статистической оценки на основе анализа взаимосвязи показателей на микроуровне (уровень отдельных предприятий-лидеров по показателю производительности труда) и макроуровне (уровень металлургической промышленности в целом), что развивает методические основы экономико-статистического анализа производственной деятельности и позволяет получать более обоснованные оценки влияния производительности труда на эффективность развития металлургической промышленности. / The issues of increasing metallurgical industrial enterprise’s economic efficiency under the influence of various factors are relevant at the present stage of Russian Federation’s economic development. In the modern economy the key factor is increasing efficiency in production through the labor productivity growth. The aim of the master's thesis is to study the effect of the labor productivity on the economic efficiency of metallurgical industrial organizations. The paper considers theoretical and applied aspects of the analysis of labor productivity and economic efficiency of metallurgical industry, as well as issues of their relationship. The sources of information used educational and research literature, official statistics and financial statements of organizations. The master's thesis developed a methodological approach to assessing the impact of labor productivity on the economic efficiency metallurgical industrial enterprises measured by returns on assets (ROA). The methodological approach involves obtaining comprehensive economic and statistical assessment based on the analysis of the relationship between indicators labor productivity and economic efficiency of metallurgical industry at the micro-level (level of individual enterprises-leaders in labor productivity) and macro-level (level of metallurgical industry as a whole), which one develops methodical basis of economic and statistical analysis and allows to obtain more reasonable estimates of the impact of labor productivity on the economic efficiency metallurgical industrial enterprises.
75

Методический подход к оценке эффективности деятельности предприятий черной металлургии в условиях экологических рисков : магистерская диссертация / A methodical approach to assessing the efficiency of ferrous metallurgy enterprises in conditions of environmental risks

Байметова, М. Г., Baymetova, M. G. January 2024 (has links)
Проведенное исследование посвящено концептуальным основам оценки эффективности деятельности предприятия в условиях воздействия металлургического производства на окружающую среду. В работе раскрывается содержание методики оценки эффективности деятельности предприятия черной металлургии в условиях экологизации производства. Методический подход предполагает последовательную реализацию нескольких этапов и основан на сбалансированной системе частных показателей, приводимых к интегральному. Результаты исследования могут быть использованы при принятии управленческого решения о перспективности инвестиционных вложений в деятельность металлургического предприятия, а также при развитии методических основ в экологии металлургии. / The conducted research is devoted to the conceptual framework for assessing the efficiency of an enterprise in terms of the impact of metallurgical production on the environment. The work reveals the content of the methodology for assessing the efficiency of a ferrous metallurgy enterprise in conditions of greening production. The methodological approach involves the sequential implementation of several stages and is based on a balanced system of partial indicators reduced to an integral one. The results of the study can be used when making management decisions about the prospects of investment in the activities of a metallurgical enterprise, as well as in the development of methodological foundations in the ecology of metallurgy.
76

Pricing-Enabled QoS Guarantee In DiffServ Network / 差異性服務環境中以收費機制提供服務品質保證

林士發, Lin,Shih-Fa Unknown Date (has links)
利用經濟理論以及分析網路資源數量與價錢的關係,提供網路供應者,可以依據目前網路壅塞的情形,讓網路使用者可以彈性選擇個人化網路服務等級,動態保證網路使用者的網路服務品質,透過經濟效益分析,構思出定價策略來保障使用者最大利益,供應者最大收益和社會最大福利。在差異性服務環境下,我們不僅支援多種網路服務等級而且允許網路使用者動態選擇適當網路資源,實驗結果顯示我們的定價方法提供網路服務等級及增加網路供應者的利潤。 / By adopting an appropriate economics theory and analyzing a close connection between quantity and price, we enable network service providers to react instantaneously to network congestions and to provide customers with high flexibility in service class selection. Economic efficiency is well established in pricing strategies to maximize customers’ net benefit, provider’s surplus and social welfare. To achieve this goal, we propose a hybrid pricing strategy which not only supports multiple QoS classes but also allows customers to make personal QoS class selections in Differentiated Service networks. Simulation results show that our pricing strategy can support customer QoS and increase ISP revenue.
77

Le contrat de distribution exclusive et le principe de la concurrence au Canada

Etienne, Gotha 08 1900 (has links)
Les contrats de distribution exclusive sont couramment utilisés dans la mise en marché des produits. Des doutes et des critiques ont été, pourtant, soulevés relativement à leur validité au regard du droit de la concurrence. Ces ententes et les pratiques qui en découlent paraissent, à première vue, anticoncurrentielles. Le propos de ce mémoire est d’examiner dans quelle mesure les contrats de distribution exclusive peuvent, en fait, stimuler la concurrence et de montrer, en conséquence, qu’ils devraient être considérés licites eu égard au droit de la concurrence. Nous trouvons, d’une part, que les pratiques exclusives sont suspectes vu qu’elles réduisent la liberté contractuelle du producteur et du distributeur. Cette restriction est susceptible d’entraver la concurrence à cause du pouvoir de marché qu’elle crée et elle peut, de ce fait, engendrer le monopole. La Loi sur la concurrence interdit de tels agissements. Les contrats de distribution exclusive peuvent, d’autre part, favoriser réellement la concurrence. Ils constituent un instrument stratégique utilisé par les entrepreneurs dans leur lutte pour accroître leur part de marché. La distribution exclusive, en portant les acteurs commerciaux à chercher les meilleures stratégies, renforce la concurrence. Celle-ci doit être entendue non seulement comme une constante rivalité entre toutes les entreprises, mais elle doit aussi inclure la coopération entre certaines entreprises en vue de mieux concurrencer d’autres à un niveau plus général. Une juste appréciation de la concurrence dans les contrats de distribution exclusive requiert le recours à l’analyse économique du droit. Cette analyse permet une évaluation de la concurrence basée sur le critère de l’efficience économique. En vue de déterminer si une pratique donnée augmente ou non le bien-être général (sur quoi l’analyse de l’efficience met l’accent), les effets négatifs de cette pratique devraient être mis en balance avec ses effets positifs résultant des gains en efficience. C’est dans ce sens que le droit de la concurrence a évolué tant dans l’Union européenne qu’aux États-Unis et au Canada pour permettre les ententes qui entraînent des gains nets d’efficience. Ce qu’on aurait pu condamner autrefois pour entrave à la concurrence, peut maintenant paraître comme une stratégie commerciale licite et saine. Compte tenu de ce récent développement, notre analyse nous conduit à la conclusion que les accords de distribution exclusive devraient être considérés licites dans la mesure où ils améliorent le bien-être du consommateur. / Exclusive distribution agreements are commonly used in the marketing of products. However, doubts and criticisms have been expressed concerning their validity as regards competition law: these agreements and the resulting practices appear at first blush to be anticompetitive. In this thesis we propose to examine to what extent exclusive distribution agreements can in fact foster competition and hence should be considered lawful as regards competition law. On one hand, we find that exclusive distribution practices are suspect, because the contractual freedom of the producer and of the distributor is restricted. This restriction may hinder interbrand competition due to market power and can potentially create a monopoly. Such actions are not permissible under the Competition Act. On the other hand, some aspects of exclusive distribution arrangements can actually promote competition. They constitute a strategic tool used by suppliers seeking to increase their market shares. This can reinforce competition by encouraging competitors to try out better strategies. Competition must be understood not merely as the constant rivalry amongst all enterprises, but must also encompass cooperation between certain enterprises in order to better compete with others at a more general level. A fair appreciation of competition in exclusive distribution arrangements requires one to have recourse to the economic analysis of law. The economic analysis of law allows one to assess competition based on the criterion of economic efficiency. In order to determine whether or not a particular practice increases the general welfare ( on which efficiency analysis focuses), the negative effects of that practice should be weighed against its positive effects resulting from efficiency gains. In this sense, competition law has evolved, as much in the European Union, as in the United States and Canada, to allow arrangements that lead to net welfare gains. What might have been previously condemned as an obstacle to competition may now appear as a legitimate and healthy commercial strategy. Taking into account this recent development, our analysis leads us to the conclusion that exclusive distribution agreements should be lawful in so far as they improve consumer welfare.
78

Modelo dinâmico para a gestão e manejo sustentável de sistemas de irrigação comunitários, no marco do Bom Viver: estudo do caso na bacia do Rio Pisque / Dynamic model for the management and sustainable operation of community irrigation systems, within the framework of Good Living: a case study in the Pisque River basin

Ulcuango, Charles Jim Cachipuendo 21 February 2018 (has links)
A disponibilidade da água fornecida para a agricultura reduz-se por efeitos das mudanças dos ciclos hidrológicos e pelo crescimento populacional, portanto, põem-se em risco a sustentabilidade dos sistemas de irrigação comunitários. Em vista de isso, os usuários da irrigação estabelecem estratégias que permitam sobrelevar as novas realidades. Sem embargo, as políticas e a análise da gestão e manejo da irrigação são feitas a partir da hidrologia, a hidráulica, sociologia e economia de forma separada, em esse sentido, o propósito de este trabalho foi estudar as inter-relações sociais, ambientais, econômicas e culturais que ocorrem nos sistemas de irrigação comunitários e como o enfoque da gestão comunitária da água estabelecida na constituição e legislação do Equador no marco do Bom Viver, ajuda a sua sustentabilidade e a melhorar o uso da água na agricultura. O estudo foi realizado em 13 sistemas de irrigação comunitários da bacia do rio Pisque, localizada na serra norte do Equador. Foi usada a metodologia de dinâmica de sistemas a qual permite, avaliar sistemas complexos de forma qualitativa e quantitativa. A participação da organização comunitária foi importante e foram usadas ferramentas como: observações em campo, entrevistas, etnografia, grupos de diálogo e avaliações de vazões e volume da água utilizada na produção agrícola. Neste trabalho se encontrou que a irrigação comunitária é concebida como um sistema integral, composto pela natureza, comunidade e infraestrutura, na qual os usuários da irrigação conformam organizações com resiliência, sendo a tecnificacão da irrigação uma estratégia para reduzir as perdas da água e incrementar a produtividade agrícola. Os indicadores, eficiência técnica e produtividade económica da água foram avaliados, em três sistemas de produção, leite, produção de flores em ambientes protegidos e na agricultura diversificada familiar, sendo a produção de flores a mais eficiente. A tecnificacão dos sistemas de irrigação melhora a agricultura, mas também provoca mudanças nos comportamentos socioculturais, no meio ambiente e nas relações socioeconômicas no território comunitário. Portanto o modelo para a gestão e manejo sustentável dos sistemas da irrigação comunitários considera estas realidades locais e conforma-se por três subsistemas, natureza, uso do solo e a comunidade, onde em cada um destes interatuam variáveis exógenas e endógenas que intervêm na sustentabilidade dos sistemas de irrigação. Incorporar variáveis sociais inerentes à comunidade na estrutura do modelo permitiu identificar e compreender o comportamento das causalidades nas variáveis da natureza e da produtividade do uso da água e do solo, de maneira que as soluções aos problemas, sejam abordadas de forma integral tendo em conta os princípios da sustentabilidade e do Bom Viver, sendo os fundamentos do enfoque da gestão comunitária da água. / The availability of water supplied to agriculture is reduced by the effects of the changes in the hydrological cycle and population growth. This fact puts at risk the sustainability of the community irrigation systems. Therefore, irrigation users stablish strategies that allow overcome new realities. However, the policies, management and operation of irrigation are done considering the hydrology, hydraulics, sociology, and economics separately. In this sense, the purpose of this work was to study the social, environmental, economic, and cultural interrelationships that occur in the community irrigation systems. In addition, this research analyses the community\'s water management approach established in Ecuador`s Constitution of 2008 focusing in the Good Living framework, which conceptually tries to reach sustainability and improve the use of water in agriculture. The study was conducted in 13 community irrigation systems at the Pisque river basin, located in the highlands in Ecuador. The methodology consisted in the systems dynamics which allows to evaluate complex systems in a qualitative and quantitative way. The participation of the community was a key element and different tools were applied such as field observations, interviews, ethnography, focus groups, and assessments of water flow and volume used in agricultural production. This study shows that community irrigation is conceived as an integrated system composed by nature, the community, and infrastructure. Within this system, the irrigation users form resilient organizations and the modernization of irrigation is a strategy to reduce water losses and increase agricultural productivity. The indicators technical efficiency and economic productivity of water were evaluated in three production systems: milk, flower production in protected environments, and family\'s diversified agriculture. The results demonstrate that flower production is the most efficient. The technification of the irrigation systems improves agriculture but also causes changes in the socio-cultural behavior, the environment, and the socio-economic relationships within the community. Thus, the model for the operation and a sustainable management of the community irrigation systems considers these local realities, and it is formed by three subsystems: nature, land use and community. Each subsystem has exogenous and endogenous variables that intervene in the sustainability of the irrigation systems. Social variables inherent to community were incorporated in the model structure which allowed identifying and understanding the behavior of the causalities in nature and water and land productivity. Therefore, solutions to problems are addressed in an integral way considering the principles of sustainability and Good Living, as fundamentals of the community\'s water management approach.
79

Dynamic efficiency under uncertainty

Wagner, Christina 24 June 2015 (has links)
Der Milchsektor ist einer der bedeutendsten landwirtschaftlichen Sektoren in der Europäischen Union. Seit die Reformen der Gemeinsamen Agrarpolitik 2005 in Kraft traten, wurde der Markt stark liberalisiert und ist durch zunehmende Preisschwankungen gekennzeichnet. Für die Michviehbetriebe ist dies eine Herausforderung, denn Faktorpreisunsicherheit ist eng mit den betrieblichen Entscheidungsprozessen für die optimale langfristige Nutzung der Produktionsfaktoren verbunden. Ein weitreichender Teil der Literatur analysiert den Zusammenhang zwischen Betriebsgröße oder Betriebsführung und ökonomischer Effizienz. Die statische Effizienzmessung ist weitverbreitet, vernachlässigt jedoch die zeitliche Abhängigkeit und die Anpassungsprozesse der quasi-fixen Faktoren. Dies wird im Konzept der dynamischen Effizienzmessung aufgegriffen. Das verwendete Effizienzmodell berücksichtigt zudem Faktorpreisunsicherheit. Der Beitrag dieser Dissertation ist es, die dynamische Effizienz westdeutscher Milchviehbetriebe erstmals unter Unsicherheit zu analysieren. Es wird untersucht, ob die Produktionsfaktoren technisch und allokativ effizient einsetzen werden. Zudem wird die Rolle der Unsicherheit für die Faktornachfrage und die Effizienzmessung beleuchtet. Die Ergebnisse zeigen, dass die Milchviehbetriebe auf einem hohen technischen Effizienzniveau arbeiten im Vergleich zur allokativen Effizienz und dass die Futternachfrage negativ mit der Futterpreisvolatilität verbunden ist. Investitionen reagieren negativ auf die Volatilität des Milchpreises, wobei der Einfluss der Unsicherheit mit zunehmender Betriebsgröße steigt. Die Ergebnisse belegen, dass die Preisunsicherheit bei der (dynamischen) Effizienzmessung von entscheidender Bedeutung ist und die Vernachlässigung zu niedrigeren Effizienzwerten führt und die Betriebe ineffizient erscheinen. Diese Ergebnisse sind nicht nur für Milchviehbetriebe relevant, sondern auch für Sektoren, die durch volatile Marktbedingungen gekennzeichnet sind. / Dairy farming, the most important farming sector in the European Union, has been subject to considerable de-regulation since the 2005 EU Common Agricultural Policy came into effect and to increased commodity price volatility. This is a new challenge for dairy farms, since price volatility is related to farm-level decision-making with regard to the optimal factor allocation in the long run. A vast body of literature relates economic efficiency to dairy farm characteristics such as size or managerial ability. However, it is common for static approaches of efficiency which ignore the role of time and the adjustment processes of farms with respect to the quasi-fixed factors to be applied. The intertemporal linkages of production and investment decisions are emphasized by dynamic efficiency and an extended model incorporates factor price volatility. The contribution of this thesis is to analyze the dynamic efficiency of German dairy farms under uncertainty, which thus far has not been done. The application aims to investigate whether West German dairy farms use their production factors in a technically and allocative efficient way in the long run. Moreover, the application will explore the role of uncertainty for factor demand and efficiency measurement. The results show that the farms operate at high levels of technical efficiency in comparison to allocative efficiency and that feed demand is negatively related to the variance of the feed concentrate price. Investment is negatively related to the variance of the milk price and the effect increases with farm size. The results further show empirical evidence for considering uncertainty when deriving (dynamic) efficiency measures: neglecting uncertainty within the estimation procedure will underestimate the average efficiency score, and thus farms appear inefficient. This finding is not only interesting for dairy farms; it also applies to other sectors that operate in highly-volatile markets.
80

Exigências de energia e proteína e composição do ganho em peso compensatório de novilhos Nelore por meio do indicador óxido de deutério / Energy and protein requirements and compensatory gain composition of Nellore steers through the marker deuterium oxide

Aferri, Gabriela 13 December 2007 (has links)
Foram utilizados 36 novilhos da raça Nelore, alojados em baias individuais em regime de confinamento, com 20 meses de idade e 359 kg no início do experimento, para determinar as exigências de energia e proteína líquidas para mantença e para ganho de peso, e também para avaliar o efeito da restrição alimentar sobre o desempenho e composição do ganho de peso, bem como o perfil hormonal dos animais e para avaliar a eficiência bioeconômica do ganho de peso compensatório em confinamento. Para isso foram realizados dois experimentos em seqüência, o primeiro teve uma duração de 58 dias e o segundo 78 dias. No primeiro foi fornecida uma mesma dieta, em três níveis de ingestão de matéria seca (MS), sendo alimentação ad libitum (TAL), 75 g MS/kg PV0,75 (T75) e 60 g MS/kg PV0,75 (T60). A composição corporal foi estimada com o óxido de deutério como marcador, que possibilitou a repetição das medidas nos mesmos animais e o estudo de suas respostas à realimentação. Os animais apresentaram exigência de energia líquida para mantença (ELm) de 0,070 Mcal/kg PV0,75 e a exigência de energia líquida para ganho (ELg) foi descrita pela equação ELg = 0,0467 * PCVz0,75 * GPCVz0,8585. A exigência de proteína metabolizável para mantença (PMm) foi determinada pela equação PMm = 4,32 * PV0,75 e a exigência de proteína metabolizável para ganho (PMg) foi de 266 g/kg GPCVz. No segundo experimento, os animais que receberam alimentação restrita na primeira fase foram alimentados ad libitum com a mesma dieta. Os hormônios avaliados foram influenciados pelo padrão de alimentação imposto aos animais e pelo ganho de peso compensatório. Animais que apresentaram ganho de peso compensatório apresentaram melhor eficiência bioeconômica. / Thirty six Nellore steers with a mean weight and age of 359 kg and 20 months at the beginning of the experiment were fed individually to determine the energy and protein requirements for maintenance and gain and also to evaluate the effect of the feed restriction on the performance and gain composition, hormonal profile and bio economic efficiency during re-alimentation. Two sequential experiments were developed, the first lasted 58 days and the second 78 days. In the first the steers were fed the same diet in three levels of dry matter intake, ad libitum (TAL), 75 g DM/kg LW0,75 (T75) and 60 g DM/kg LW0,75 (T60). The body composition was estimated with the marker deuterium oxide that allowed repeated water estimative of the same animal and the re-alimentation study. The steers had a net energy requirement for maintenance (NEm) of 0,070 Mcal/kg EBW0,75 and the net energy requirement for gain (NEg) was described by the equation NEg = 0,0467 * EBW0,75 * LWGVz0,8585. The metabolizable protein requirement for maintenance (MPm) was described by the equation MPm = 4,32 * LW0,75, and the metabolizable protein for gain (MPg) was 266 g/kg ELWG. In the second experiment the animals that had restricted intake in the first phase were fed ad libitum. The hormones evaluated were influenced by the feeding pattern that the animals were submitted and by the compensatory weight gain. Animals that showed compensatory gain had greater bio economic efficiency.

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