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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

Ecoeficiência em iluminação pública / Eco-efficiency in street lighting

Oswaldo Sanchez Junior 15 March 2016 (has links)
Na busca por eficiência energética em serviços e produtos de iluminação pública, a maioria das iniciativas concentra-se em procedimentos voltados estritamente à substituição de tecnologias convencionais por outras mais energeticamente eficientes, considerando somente a fase de operação, onde há mais consumo de energia, e o investimento inicial. No entanto, verifica-se que há uma carência de estudos dedicados à análise da sustentabilidade urbana, em particular com o foco na ecoeficiência das iniciativas, em que pese o crescente interesse das empresas por produtos economicamente e ambientalmente sustentáveis. Portanto, a qualidade do serviço de iluminação pública quanto à sua ecoeficiência (componente importante da sustentabilidade urbana) pode ser desenvolvida utilizando-se o pensamento de ciclo de vida de forma simplificada para avaliar tanto economicamente quanto ambientalmente o empreendimento, de modo a viabilizar a comparação de tecnologias, desenvolvimento de projetos e a tomada de decisão para gestores. O objetivo do presente trabalho é propor um modelo analítico que permita, tanto os desenvolvedores de produtos e projetos como a gestores de serviços de Iluminação Pública IP, gerenciar seus recursos para garantir maior ecoeficiência na transição para tecnologias mais avançadas (como o uso de LEDs em produtos), que mitigam os impactos ambientais e o custo desta transição. Como método, utilizou-se uma abordagem qualitativa, se aplicou a técnica de Avaliação de Ciclo de Vida (ACV) para avaliação ambiental e econômica de produtos e instalações para IP baseados na tecnologia convencional e produtos com tecnologia LED. Com isso obteve-se uma medida da ecoeficiência associada a diferentes soluções. Na sequência, as informações foram analisadas, comparadas e um conjunto de parâmetros foi definido para constituir um modelo para tomada de decisão. Em particular, foi dada ênfase à qualidade da iluminação na definição da Unidade Funcional. Todas as fases do ciclo de vida foram analisadas (extração de matérias primas, fabricação de componentes, integração e fabricação de luminárias, manutenção e descarte). Como resultados, foram obtidos critérios mínimos de comparação para instalações de Iluminação Pública a LED; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) em termos de emissões de gases de efeito estufa (CO2 equivalentes) do setor de IP; identificação dos impactos de novas tecnologias (como uso da tecnologia LED) no Custo do Ciclo de Vida de instalações para IP e foi desenvolvido um Modelo de Análise para integrar o desempenho econômico ao ambiental (ecoeficiência) de produtos e instalações de IP. / Introduction: in the search for energy efficiency services and street lighting products, most of the initiatives focuses on procedures aimed strictly to the replacement of conventional technologies by more energy efficient ones considering only their use phase. However, it turns out that there is a lack of studies dedicated to analyzing this field with a focus on eco-efficiency initiatives, despite the growing interest of companies by products economically and environmentally sustainable. Therefore, the quality of the street lighting service for their eco-efficiency can be developed using the Life Cycle Assessment (LCA) technique in a systematic and objective manner, in order to facilitate the comparison of technologies, project development and decision making for managers. Objective: To generate an analytical model that allows both product and project developers and managers of street lighting services to manage its resources to ensure greater eco-efficiency in the transition to more advanced technologies (such as the use of LEDs in products) that mitigate the environmental impacts and the cost of this transition. Method: it was applied the LCA for environmental and economic evaluation of products and street lighting facilities based on conventional technology and products with LED technology. Further, the information was analyzed, compared and a set of parameters has been set to provide a model for decision-making. In particular, it was given emphasis to the quality of lighting in the definition of a functional unit. Every stage of the life cycle was analyzed (extraction of raw materials, component manufacturing, integration and manufacturing lighting fixtures, maintenance and disposal). Results: we obtained minimum criteria of comparison for Street Lighting LED installations, identifying the impact of new technologies (such as use of LED technology) in the carbon footprint of the street lighting industry. Besides, we identified the impact of new technologies (such as use of LED technology) in the cost of life cycle of street lighting facilities. Lastly, it was developed an Analysis Model to integrate environmental economic performance (eco-efficiency) products and street lighting facilities.
72

Non-parametric modelling of pollution-generating technologies : theoretical and methodological considerations, with an application to the case of greenhouse gas emissions in suckler breeding systems in French grassland areas / la modélisation non paramétrique des technologies génératrices de pollution : considérations théoriques et méthodologiques, avec une application au cas des émissions de gaz à effet de serre dans les systèmes d'élevage allaitant dans les zones de prairies françaises

Dakpo, K. Hervé 15 June 2015 (has links)
La prise en compte des problèmes environnementaux dans la responsabilité sociale des entreprises a généré en économie de nombreuses propositions. Parmi elles, le cadre d’analyse basé sur l’évaluation de la performance en utilisant notamment les techniques d’enveloppement des données (DEA) s’est très vite répandu dans la littérature théorique comme empirique. Ce travail de thèse s’inscrit dans cette logique en mettant l’accent sur la modélisation des technologies polluantes. Par ailleurs, la question des changements climatiques et de la forte contribution de l’agriculture et en particulier de l’élevage dans les émissions de gaz à effet de serre (GES) impose à ce secteur de relever aujourd’hui en plus du défi économique celui de l’amélioration de sa performance environnementale. L’objectif général de cette recherche doctorale est donc de fournir un nouveau cadre d’analyse théorique et empirique dans la modélisation des technologies polluantes afin d’évaluer l’éco-efficience des systèmes productifs, en particulier le cas des émissions de GES en élevage extensif de ruminants. Dans un premier temps, nous montrons les limites théoriques et méthodologiques des modèles existants. Néanmoins, nous insistons sur le fait que les approches basées sur l’estimation de plusieurs sous-technologies indépendantes pour prendre en compte les différents processus présents dans les systèmes productifs sont très prometteuses. Dès lors dans un deuxième temps, nous proposons une nouvelle extension de la méthode « by-production » qui repose sur l’introduction d’interconnections entre les différentes sous-technologies impliquées afin de construire un système plus unifié. Dans un troisième temps, une comparaison empirique utilisant des données d’exploitations de viande ovine de notre extension avec les approches existantes a révélé certaines incohérences de ces dernières. Enfin pour aller plus loin, nous élargissons dans un quatrième temps notre approche afin de prendre en compte les aspects dynamiques et notamment la présence de coûts d’ajustement. Les résultats de l’analyse empirique entreprise avec des données d’exploitations bovines allaitantes (viande) ont révélé la nécessité de prendre en compte ces aspects, mais ont aussi révélé la forte hétérogénéité existante dans les stratégies d’investissements des éleveurs. / The growing importance of environmental matters in social responsibility of firms has generated many frameworks of analysis in the economic literature. Among those frameworks, performance evaluation and benchmarking using the non-parametric Data Envelopment Analysis (DEA) have increased at a very fast rate. This PhD research focuses on models that include undesirable outputs such as pollution in the overall production system, to appraise eco-efficiency of decision making units (DMUs). Besides, the recent awareness on the large contribution of agriculture and particularly livestock farming to global warming, has highlighted for this sector the challenge of reaching both economic and environmental performances. In this line, the overall objective of this dissertation is to provide a theoretical and empirical background in modelling pollution-generating technologies and to suggest theoretical improvements that are consistent with the particular case of greenhouse gas emissions in extensive livestock systems. Firstly, we showed that all existing approaches that deal with undesirable outputs in the non-parametric analysis (i.e. DEA) have some strong drawbacks. However, the models grounded on the estimation of multiple independent sub-technologies offer interesting opportunities. Secondly, I developed a new framework that extends the by-production approach through the introduction of some explicit dependence constraints that link the sub-technologies in order to build a unified system. Thirdly, an empirical comparison, using a sample of French sheep meat farms, of this by-production modelling extension with the existing approaches, revealed some inconsistencies of these latter. Finally, we expanded this new by-production formulation to account for dynamic aspects related to the presence of adjustment costs. The application to the case of French suckler cow farms underlined the necessity of accounting for dynamic aspects and also showed high heterogeneity in investment strategies of these farmers.
73

Eco-conception des motorisations électriques : Application à la machine asynchrone / Eco-design of electrical motors : Application to the induction machine

Boughanmi, Walid 30 November 2012 (has links)
Environ 300 millions de moteurs électriques, de puissance moyenne comprise entre 0,75 kW et 300 kW, sont utilisés dans l’industrie, l’infrastructure et les grands bâtiments. En plus, 30 millions sont renouvelés chaque année. En France, l’énergie électrique consommée par ces moteurs représente environ deux-tiers l’énergie électrique consommée dans l’industrie. Une amélioration, même faible, des performances environnementales de chaque unité apporte donc des gains environnementaux conséquents. La démarche d’éco-conception d’une machine électrique permet d’introduire, contrairement aux autres démarches classiques, les aspects environnementaux lors de la conception de la machine en tenant compte de toutes les phases du cycle de vie, depuis l’extraction des matières premières nécessaires à la fabrication des pièces de la machine jusqu’à son démantèlement et son recyclage. Cette démarche permet de concevoir une machine électrique avec un meilleur écobilan global. Dans ce travail, un outil performant destiné à l’Analyse du Cycle de Vie (ACV), prenant en compte plusieurs critères d’impacts afin d’éviter le transfert de pollution d’un critère à l’autre, a été utilisé pour améliorer significativement les performances éco-énergétiques des moteurs électriques. Un premier prototype de moteur « vert » réalisé avec de nouveaux concepts a été fabriqué et comparé à une machine de référence. Sa réalisation a été dictée par le souci de réduire au maximum son empreinte environnementale en utilisant des matériaux plus respectueux de l’environnement, mais aussi en augmentant son efficacité énergétique. Le prototype est ainsi fabriqué à base de tôle à grains orientés, de fil émaillé UV sans solvant, de plastique d’origine végétale et de roulements éco-énergétiques. Ce moteur prototype possède une haute éco-efficacité énergétique puisque son rendement est augmenté de l’ordre de trois points par rapport au moteur standard, sans augmenter sa masse, de plus il comporte un système d’isolation qui n’utilise pas de solvant et des plastiques biosourcés. / Approximately 300 million of electric motors, with average power range from 0.75 kW to 300 kW, are used in industry, infrastructure and large buildings. In addition, 30 millions are renewed each year. In France, the electrical power consumed by these motors is about two-third of the electrical energy consumed in the industry. Thus, an improvement, even small, of the environmental performance of each motor would provide substantial environmental benefits. Contrary to the conventional approaches, the eco-design of an electrical machine can introduce environmental aspects during the design of the machine, taking into account all phases of the life cycle from the extraction of raw materials to the decommissioning and the recycling. This approach has been applied in this study to design an electrical motor, which has a better global energetic eco-balance. Therefore, a Life Cycle Analysis (LCA) tool is used; it takes into account several impact criteria to avoid pollution transfers from one criterion to another. A first "Green" prototype motor made with a high energetic eco-efficiency was fabricated and tested. The study was dictated by the need to minimize its global environmental impact by using materials more environmentally friendly, but also in order to increase its energy efficiency. The prototype is made with a grain oriented steel sheets, an enameled wire polymerized by UV and without solvents, some plastic based on biopolymers and with eco-energetic bearings. The eco-designed motor has a high energetic eco-efficiency; its performance is increased by about 3 % compared to the standard motor and without increasing its mass.
74

SUSTAINABILITY PERFORMANCE EVALUATION MANAGEMENT SYSTEMS MODEL FOR INDIVIDUAL ORGANIZATIONS AND SUPPLY CHAINS

Coelho, Jose Flavio Guerra Machado, f.coelho@bigpond.com January 2006 (has links)
The title of the research is Sustainability Performance Evaluation Management Systems Model for Individual Organizations and Supply Chains. This research has achieved its aim to develop and demonstrate the practical implementation of a simple and objective sustainability performance evaluation management system model for individual organizations and supply chains. It has resulted in the recognition that a new concept – Network of Interested Partners – underpins the achievement of sustainability. The term acknowledges the interdependence and reflects the essential cooperation that must be achieved between business organisations, their commercially related entities and the local community if progress towards sustainability is to be achieved. It therefore encompasses and extends the concept of a supply chain as currently used. Sustainable Development is defined by the World Commission on Environment and Development as development, which meets the needs of the present without compromising the ability of future societies to meet their own needs. Organizations, as part of human activities, also have to be sustainable. The sustainability of organizations is directly linked to the continual improvement of business performance. Many organizations have found a way to improve performance through the establishment of management systems. International Organization for Standardization (ISO) standards are recognized worldwide as reliable and efficient tools for the implementation of management systems. However, they do not always result in the desired improvement in outcomes. Therefore, if the required improvement of business performance is to be achieved, improved methodologies for development and implementation of performance evaluation (PE) processes are necessary. These methodologies must take into consideration sustainability principles. They also have to be applicable to individual entities and supply chains, with or without management systems in place. Supply chains are important because it is being increasingly recognized that overall supply chain performance is a means of adding value and competitive advantage to all businesses. In the first part of the research a performance evaluation model or PE (version 1 model) was developed. This was used as criteria to compare and evaluate existing performance evaluation processes and outcomes of individual organisations and their respective supply chain within the Gladstone region, Australia. Questionnaires have also been used to identify and evaluate the needs of the interested parties in relation to the organizations’ and supply chains’ business performance and processes of performance evaluation. All the information provided in the first part of the research was used by the researcher to develop the Sustainability Performance Evaluation Management Systems model or SPEMS (version 2 model). This incorporates the concepts of Network of Interested Parties/Partners. In particular, one of the outcomes is recognition that organizations need to establish partnerships if effective supply chain performance improvement is to be achieved. Therefore the establishment of partnerships has become a key requirement for the implementation of SPEMS. The establishment of partnership among participants of a supply chain of Gladstone and implementation of the eight first steps of the SPEMS (version 2 model) in this supply chain was commenced successfully through workshops. The supply chain was formed by commercial organizations, government entities and interested parties from the community. SPEMS requires that partners all have the same level of ownership and authority in the decisions of the supply chain. Some new terms and their definitions have been created within the research to support the new SPEMS model. They include: Network of Interested Partners, sustainability for organizations, sustainability KPI and sustainability friendly organizations. All of the above are encompassed within the final SPEMS (version 3 model).
75

Essays in international trade and energy / Essais dans le commerce international et l'énergie

Monastyrenko, Evgenii 24 September 2018 (has links)
Dans le chapitre 1, j’examine les résultats des fusions entre producteurs européens d’énergie en termes d’efficacité. Je calcule l’éco-efficacité en utilisant l’analyse de l’enveloppement des données et l’indice de productivité Malmquist-Luenberger. Je trouve que les fusions horizontales nationales, qui sont soigneusement réglementées, n’ont pas d’impact. Les fusions horizontales transfrontalières nuisent à l’éco-efficacité à court terme mais la stimulent deux ans après l’achèvement. Les fusions verticales nuisent à l’éco-efficacité. Je présente des suggestions de politiques concernant la réglementation des fusions. Le chapitre 2 est un travail conjoint avec Julian Hinz. Nous enquêtons sur les effets de l’embargo russe auto-imposé sur les importations de produits alimentaires en provenance des pays occidentaux. Nous construisons un modèle ricardien avec des liens sectoriels, des échanges de biens intermédiaires et une hétérogénéité sectorielle dans la production. L’étalonnage du modèle avec des données réelles permet de simuler les résultats de l’embargo en termes de changements de bien-être et de prix. Nous quantifions en outre l’impact sur les prix à la consommation en Russie à l’aide de la méthode des doubles différences. Le chapitre 3 est basé sur un article co-écrit avec Cristina Herghelegiu. Nous enquêtons sur l’utilisation des conditions commerciales internationales (Incoterms). Ce sont les schémas prédéfinis de la répartition des coûts et des risques entre les acheteurs et les vendeurs. Nous nous appuyons sur un ensemble de données très détaillées sur les exportations russes durant la période 2012-2015. Nous constatons que les grandes entreprises sont plus susceptibles d’assumer des responsabilités. Les gros acheteurs assument plus de responsabilités, quelle que soit la taille du vendeur, alors que les gros vendeurs le font uniquement lorsque leur partenaire est petit. C’est plus probable que les risques et les coûts sont sur les acheteurs dans les transactions de biens intermédiaires et de biens d’équipement. / In Chapter 1 I investigate firm-level efficiency outcomes of mergers between the European energy producers. I compute eco-efficiency using data envelopment analysis and the Malmquist-Luenberger productivity index. I find that carefully regulated domestic horizontal mergers do not have a statistically significant impact. Cross-border horizontal mergers hamper eco-efficiency in the short run but stimulate it two years after completion. Vertical mergers are detrimental to eco-efficiency. I put forward policy suggestions regarding the regulation of mergers. Chapter 2 is joint work with Julian Hinz. We investigate the effects of self-imposed Russian embargo on food import from Western countries. We build a Ricardian model with sectoral linkages, trade in intermediate goods and sectoral heterogeneity in production. The calibration of the model with real data allows to simulate the outcomes of embargo in terms of changes in welfare and prices. We further quantify the impact on consumer prices in Russia with the difference-in-differences estimator. Chapter 3 is based on a paper co-written with Cristina Herghelegiu. We investigate the use of International Commercial Terms. They are pre-defined schemes of repartition of costs and risks between buyers and sellers, which serve to mitigate the uncertainty. We rely on a highly detailed dataset on Russian exports over the 2012-2015 period. We find that big firms are more likely to take on responsibilities. Big buyers bear more responsibilities regardless of the seller size, whereas big sellers do so only when their partner is small. Risks and costs are more likely on buyers in transactions of intermediate and capital goods.

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