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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.
81

O planejamento energético brasileiro na perspectiva da oferta e da demanda de gás liquefeito de petróleo e eletricidade / Brazilian energy planning in the perspective of supply and demand of liquefied petroleum gas and electricity

Sgarbi, Felipe de Albuquerque 11 April 2018 (has links)
Garantir o suprimento dos insumos energéticos demandados pelos diferentes setores da economia é indispensável para o desenvolvimento socioeconômico e a soberania de uma nação. De maneira geral, a busca pela segurança energética requer o monitoramento contínuo dos diferentes fatores que podem interferir na evolução da demanda e oferta de energia. Pelo lado da demanda, tais fatores incluem a atividade econômica, o desenvolvimento tecnológico (principalmente aquele relacionado à eficiência energética dos processos), a renda e os hábitos de vida da população, entre outros aspectos. Pelo lado da oferta, poder-se-iam citar, por exemplo, as descobertas de novas e o exaurimento de antigas reservas energéticas, mercados nacionais e internacionais de energia, o desenvolvimento de novas tecnologias de conversão energética e a evolução do arcabouço legal que regula esta atividade. O estudo integrado destas variáveis, tal como definido, de forma ampla, pelo termo Planejamento Energético, permite que riscos e oportunidades associados à segurança energética sejam antecipados e, assim, evitados, mitigados ou potencializados. Neste contexto, a presente tese é composta por quatro artigos focados em diferentes aspectos da demanda e oferta de energia no Brasil: A experiência brasileira com o gás liquefeito de petróleo implicações para políticas públicas; Impactos socioeconômicos e ambientais de usinas hidrelétricas; O papel do setor elétrico brasileiro no contexto do Acordo de Paris e Avaliação da composição dos custos socioambientais de usinas hidrelétricas. A partir de análises sobre tendências de consumo residencial de gás liquefeito de petróleo (GLP) e o papel da temática ambiental no desenvolvimento da matriz de geração de eletricidade, discutem-se perspectivas para o setor energético brasileiro. Os trabalhos apresentados identificam desafios com os quais o país possivelmente terá que lidar para expandir a sua oferta de energia, e, assim, espera-se, contribuem para solidificar o arcabouço teórico sobre o qual o planejamento energético brasileiro é construído. / Ensuring the supply of the energy inputs demanded by the different sectors of the economy is indispensable for the socioeconomic development and the sovereignty of a nation. In general, the search for energy security requires the continuous monitoring of the different factors that may interfere in the evolution of the demand and supply of energy. On the demand side, these factors include economic activity, technological development (mainly the one related to the energy efficiency of processes), income and habits of the population, among other aspects. On the supply side, in can be mentioned, as examples, new discoveries and the exhaustion of old energy reserves, national and international energy markets, the development of new energy conversion technologies and the evolution of the legal framework that regulates this activity. The integrated study of these variables, as broadly defined by the term \"Energy Planning\", enables risks and opportunities associated with energy security to be anticipated and thus avoided, mitigated or enhanced. In this context, the present thesis is composed of four articles focused on different aspects of demand and supply of energy in Brazil: \"The Brazilian experience with liquefied petroleum gas - implications for public policies\"; \"Socioeconomic and environmental impacts of hydropower plants\"; \"The role of the Brazilian electricity sector in the context of the Paris Agreement\" and \"Evaluation of the composition of the socio-environmental costs of hydropower plants\". Based on analyzes of trends in residential consumption of liquefied petroleum gas (LPG) and the role of environmental issues in the development of the electricity generation mix, Brazilian energy sector perspectives are discussed. The papers presented identify challenges that the country may have to deal with in order to expand its energy supply, and thus contribute to solidifying the theoretical framework on which Brazilian energy planning is built.
82

Por uma cultura ecológica / The pursuit of the Ecological Culture

Gomez-Rivera, Sara Maria 13 August 2010 (has links)
O presente trabalho busca compreender e analisar a partir de um ponto de vista conceitual o termo cultura ecológica, que vem sendo usado como sinônimo de uma infinidade de conceitos associados à racionalidade econômica capitalista. O objetivo principal deste trabalho não é definir o quê é cultura ecológica, mas apontar as suas possíveis potencialidades conceituais, já que até agora tem se forjado como um termo mais normativo do que conceitual. Este trabalho propõe uma análise teórica - critica do termo e de vários aspectos ligados a ele, questionando e refletindo sobre a atual crise socioambiental. Primeiramente faz-se uma análise dos termos cultura, ecologia e cultura ecológica, apontando para os usos atuais desta idéia. Baseando-se em alguns aspectos teóricos de Karl Marx, de Max Weber e usando o conceito de cultura política de Gabriel Almond e Sidney Verba, analisaram-se algumas possibilidades de estudo da cultura ecológica. Depois, refletiu-se sobre a relação entre idéias e práticas ecológicas apoiando-se no conceito de práxis, o que levou também a tratar do espaço público, da cidadania e do individualismo. / This study aims to understand and analyze from a conceptual point of view the term ecological culture, which has been used as a synonymous of several concepts associated to the capitalist economic rationality. Thus, the main objective is not to define what ecological culture is, but to point at the possible conceptual potentialities, since it has been shaped as a normative term, instead of a conceptual one. This study suggests a theoretical and critical analysis of the term and of several aspects linked to it, inquiring and reflecting on the current socio environmental crisis. First of all, an analysis of the terms culture, ecology and ecological culture is done, pointing at the current usages of the term ecological culture. Some possibilities of study of the ecological culture are analyzed based upon theoretical aspects from Karl Marx, Max Weber and using the political culture concept from Gabriel Almond and Sidney Verba. Finally, a reflection on the relation between ecological ideas and practices is made using the praxis concept, what leads to treat about public sphere, citizenship and individualism.
83

An analysis of the management and economics of salmon aquaculture

Liu, Yajie 05 1900 (has links)
Salmon aquaculture can be a potential solution to bridge the gap between declining capture fisheries and increasing seafood demand. However, the environmental impacts it creates have generated criticism. The overall objectives of this dissertation are to examine the economic consequences of environmental issues associated with salmon aquaculture, and to explore policy implications and recommendations for reducing environmental impacts. These objectives are addressed in five main analyses. The growth of salmon aquaculture is analyzed based on farmed salmon production in the four leading producing countries and the sector as a whole. Analyses indicate that salmon aquaculture is unlikely to continue to grow at its current pace. A joint production function approach is used to estimate pollution abatement costs for the salmon aquaculture industry. Results reveal that pollution abatement costs vary among observations and models. On average, pollution abatement cost is estimated at 3.5% in terms of total farmed salmon production, and 6.5% in terms of total revenue of farmed salmon. The ecological and economic impacts of sea lice from salmon farms on wild salmon population and fisheries are also studied. Analyses suggest that these effects are minor when the sea lice induced mortality rate is below 20%, while they can be severe if the mortality is greater than 30%. Sea lice have greater ecological and economic impacts on pink salmon than on chum salmon. These effects are greater under a fixed exploitation rate than under a target escapement policy. The economic performance of open netcage and sea-bag production systems for salmon aquaculture is compared. Netcage systems appear to be more economically profitable than sea-bag systems when environmental costs are either not or only partially included. Sea-bag systems can be financially profitable only when the salmon they produce can achieve a price premium. Finally, policy implications are explored and recommendations are made for sustaining salmon aquaculture in a holistic manner based on the results from previous chapters. Technologies, economic-based instruments and more stringent environmental policies can be employed to reduce environmental impacts. However, there is no single solution to solve these environmental impacts, and a combination of policy options is needed.
84

An Integrated Multi-model Approach for Predicting the Impact of Household Travel on Urban Air Quality and Simulating Population Exposure

Hatzopoulou, Marianne 19 January 2009 (has links)
The population and economic growth experienced by Canadian metropolitan areas in the past twenty years, has been associated with increased levels of car ownership and vehicle kilometres travelled leading to a deterioration of air quality and public health and an increase in greenhouse gas emissions. The need to modify urban growth patterns has motivated planning agencies in Canada to develop a broad range of policies aiming at achieving a more sustainable transportation sector. The challenge however, remains in the ability to test the effectiveness of proposed policy measures. This situation has led to a renewed interest in integrated land-use and transport models to support transport policy appraisal. This research is motivated by the need to improve transport policy appraisal through the use of integrated land-use and transport models linked with a range of sub-models that can reflect transport externalities. This research starts with an exploration of the transport policy environment in Canada through a questionnaire-based survey conducted with planners and policy-makers. The survey results highlight the need for tools reflecting the sustainability impacts of proposed policies. While the second part of this research explores sustainability indicators and recommends a set of social, economic, and environmental measures, linked with integrated land-use and transport models; effort is dedicated to estimate the environmental indicators as part of this thesis. As such, the third part of this research involves the development of an emission-dispersion-exposure modelling framework. The framework includes a suite of sub-models including an activity-based travel demand model (TASHA), an emission factor model (Mobile6.2C), a meteorological model (CALMET), and a dispersion model (CALPUFF). The framework is used to estimate link-based emissions of light-duty vehicles in the Greater Toronto Area under a base scenario for 2001. Dispersion of emissions is then conducted and linked with population in order to estimate exposure to air pollution.
85

An Integrated Multi-model Approach for Predicting the Impact of Household Travel on Urban Air Quality and Simulating Population Exposure

Hatzopoulou, Marianne 19 January 2009 (has links)
The population and economic growth experienced by Canadian metropolitan areas in the past twenty years, has been associated with increased levels of car ownership and vehicle kilometres travelled leading to a deterioration of air quality and public health and an increase in greenhouse gas emissions. The need to modify urban growth patterns has motivated planning agencies in Canada to develop a broad range of policies aiming at achieving a more sustainable transportation sector. The challenge however, remains in the ability to test the effectiveness of proposed policy measures. This situation has led to a renewed interest in integrated land-use and transport models to support transport policy appraisal. This research is motivated by the need to improve transport policy appraisal through the use of integrated land-use and transport models linked with a range of sub-models that can reflect transport externalities. This research starts with an exploration of the transport policy environment in Canada through a questionnaire-based survey conducted with planners and policy-makers. The survey results highlight the need for tools reflecting the sustainability impacts of proposed policies. While the second part of this research explores sustainability indicators and recommends a set of social, economic, and environmental measures, linked with integrated land-use and transport models; effort is dedicated to estimate the environmental indicators as part of this thesis. As such, the third part of this research involves the development of an emission-dispersion-exposure modelling framework. The framework includes a suite of sub-models including an activity-based travel demand model (TASHA), an emission factor model (Mobile6.2C), a meteorological model (CALMET), and a dispersion model (CALPUFF). The framework is used to estimate link-based emissions of light-duty vehicles in the Greater Toronto Area under a base scenario for 2001. Dispersion of emissions is then conducted and linked with population in order to estimate exposure to air pollution.
86

Sustainable phosphorus removal in onsite wastewater treatment

Eveborn, David January 2013 (has links)
Aquatic eutrophication is a serious environmental problem that occurs all over the world. To protect surface waters (in particular the Baltic Sea), the regulatory pressure on onsite wastewater treatment (OWT) systems have increased in Sweden. Stringent requirements have led to uncertainties regarding the capability of conventional treatment techniques (soil treatment systems (STS)) to remove phosphorus (P), but they have also stimulated the development and introduction of enhanced P treatment techniques. In this thesis the accumulation and mobility of P as well as the chemical P removal mechanisms were studied in soils and reactive filter media. This knowledge was then used in environmental systems analysis. A model based on life cycle assessment (LCA) methodology was developed to evaluate the overall environmental performance of conventional and enhanced P treatment systems under various local conditions. The P accumulation in the studied STS varied (320-870 g m-3) and the accumulated P was rather mobile in some soils. Phosphorus compounds were identified in alkaline reactive filter media (calcium phosphates predominated) by means of X-ray Absorption Near Edge Structure (XANES). In sandy soils from STS aluminium was found to be a key element for P removal, as evidenced by a strong relationship between oxalate-extractable P and Al. The LCA studies indicated that enhanced P treatment systems may be beneficial from an eutrophication and P recycling perspective but causes increased impacts in terms of global warming and acidification. Despite the drawbacks, enhanced P treatment techniques should be considered suitable substitutes to surface water discharge STS under most conditions. This is because the latter systems have such a strong eutrophication impact. On the other hand, under appropriate conditions, STS with groundwater discharge may be advantageous. These systems generally caused low environmental impacts except for the dispersion of P resources. / <p>QC 20130419</p>
87

Life Cycle Assessment of Cruising Ship Superstructure

Hou, Qianqian January 2011 (has links)
This thesis project was conducted to compare the environmental impacts between two types of material for a superstructure of cruising ship (Norwegian Gem) using life cycle assessment (LCA) methods. With the increasing price of industrial raw materials and finite resources, more and more corporations or manufacturers endeavor in seeking more economical materials and less environmental impacts within the ship building field. In recent years, lightweight composite material has been applied in various industrial fields, for instance, green buildings, aircraft and wind turbine blade. In order to study impacts of steel superstructure and composite material superstructure of the ship, a detail study was conducted which using the comparative LCA method and SimaPro software. Two different superstructures are compared, steel superstructure and sandwich material superstructure. The results showed thatover the life cycle the environmental impacts of sandwich superstructure type are much less than for the steel superstructure. The main contribution of impacts over the life time is operation phase due to fuel consumption. When increasing the waste recycling section for composite structure, the influence on environment has an obvious decrease compared to steel superstructure.
88

Monitoring Expertise: A perspective on environmental impacts monitoring in northeast British Columbia

Twerdoclib, Christine 08 September 2015 (has links)
The shale gas industry in northeast British Columbia is rapidly expanding and is promoted by the provincial government as a promising economic venture for the entire province. However, the industry is having impacts on the traditional territory of the Fort Nelson First Nation, although they have constitutionally recognized treaty rights to continue to use the land to meet their subsistence needs. I conducted this research in partnership with the Fort Nelson First Nation Department of Lands and Resources, with a focus on critically assessing the challenges they face. This research focuses on determining how the Fort Nelson First Nation can protect their treaty rights by taking control of, or inserting themselves into the data collection and monitoring activities of the shale gas industry. Utilizing a theory of knowledge politics, this research analyzes two strategies that challenge what knowledge should count, and on what terms: (1) the Fort Nelson First Nation’s participation and appropriation of the professionalized science regime and (2) the development of the Fort Nelson First Nation’s community-based monitoring program and its ability to impact decision-making. Drawing on primary research, participant observation, literature reviews and document analyses, I argue that these strategies are crucial and can create – but do not guarantee – links to affecting natural resource management decisions. / Graduate
89

Η ανάλυση κύκλου ζωής ώς εργαλείο εκτίμησης των περιβαλλοντικών επιπτώσεων. Η περίπτωση της παραγωγής αλεύρων σε Ελληνική βιομηχανία / Life cycle assessment as a tool for assessing the environmental impacts. The case study of the flour production in Greek industry

Ζυγούρας, Γεώργιος 28 June 2007 (has links)
Οι καταναλωτές τα τελευταία χρόνια ενδιαφέρονται ολοένα και περισσότερο για την προέλευση και την ποιότητα των τροφίμων, συμπεριλαμβανομένης και της προέλευσης των Ά υλών. Η ασφάλεια, η θρεπτική αξία και πιο πρόσφατα οι περιβαλλοντικές επιπτώσεις των συστημάτων παραγωγής και διανομής των τροφίμων επίσης αντιμετωπίζονται με ανάλογο ενδιαφέρον. Το αλεύρι είναι το κύριο συστατικό του ψωμιού που θεωρείται ως η βάση της υγιούς διατροφής παγκοσμίως, των προϊόντων ζαχαροπλαστικής και άλλων αρτοσκευασμάτων. Επιπλέον στις μεσογειακές χώρες τα προϊόντα αυτά βρίσκουν μεγάλη αποδοχή από τους καταναλωτές. Στην Ελλάδα το αλεύρι καλλιεργείται σε σημαντικές ποσότητες και οι αλευροβιομηχανίες εφοδιάζουν τις βιομηχανίες τροφίμων και τους φούρνους αρτοποιίας με πολλούς τύπους αλεύρου. Οι ανάγκες της χώρας για τα διάφορα προϊόντα αλεύρου παρουσιάζουν ένα μέσο ετήσιο ρυθμό αύξησης περίπου 1,5% για τη διετία 1999-2000, ενώ οι ανάγκες για το έτος 2000 ήταν 753.000 τόνοι. Για το ίδιο έτος η εθνική παραγωγή ανέρχεται σε 825.000 τόνους. Η Ανάλυση Κύκλου Ζωής (ΑΚΖ) είναι ένα σχετικά νέο περιβαλλοντικό εργαλείο λήψης αποφάσεων που πρόσφατα τυποποιήθηκε από το Διεθνή Οργανισμό Προτύπων (International Standardisation Organisation (ISO)). Η ΑΚΖ είναι ένα εξαιρετικό εργαλείο για την περιβαλλοντική διαχείριση, καθώς παρέχει σημαντικές πληροφορίες για τους περιβαλλοντικούς κινδύνους που σχετίζονται με ένα προϊόν, μια διαδικασία ή οποιαδήποτε ανθρώπινη δραστηριότητα γενικότερα. Σε αυτή τη μελέτη μια απλουστευμένη ΑΚΖ εφαρμόζεται με μια προσέγγιση «από τη γέννηση ως την πύλη» (“cradle-to-gate”) για να αναγνωρισθούν τα κρίσιμα σημεία της διαδικασίας παραγωγής του αλεύρου στην Ελλάδα. Το λογισμικό SimaPro χρησιμοποιήθηκε για την ανάλυση των δεδομένων της απογραφής και της εκτίμησης των επιπτώσεων του συστήματος συνολικά (από τους σπόρους σιταριού ως την παραγωγή του αλεύρου). Το σύστημα που αναλύθηκε περιλαμβάνει την καλλιέργεια μαλακού σιταριού, τη μεταφορά, τη βιομηχανική άλεση και τη συσκευασία του αλεύρου. Η χρήση ενέργειας και υλικών, καθώς και οι εκπομπές στο περιβάλλον υπολογίσθηκαν και εκτιμήθηκαν τα κύρια δυναμικά των περιβαλλοντικών επιπτώσεων. Η εφαρμογή των λιπασμάτων, η μεταφορά και η χρήση ηλεκτρικής ενέργειας βρέθηκαν να είναι τα πιο σημαντικά σημεία για τις περισσότερες, όχι όμως για όλες, τις κατηγορίες επιπτώσεων και συγκεκριμένες ενέργειες προτάθηκαν με στόχο τη βελτίωση του περιβαλλοντικού προφίλ του τελικού προϊόντος. / Consumers have become increasingly interested in the origin and the quality of their food, including the source of food’s raw materials, its safety and nutritional value and most recently the environmental impacts of the production systems adopted in producing and delivering the food. Flour is the main ingredient of bread, cakes, pastries and other bakery products which are considered as the base of modern healthy diet worldwide. Moreover, in Mediterranean countries these products have an outstanding acceptance by consumers. In Greece, wheat is cultivated in significant quantities and a number of milling industries supply the food industries and small bakeries with many different types of flour. The national demand for various products of flour-producing industries presented a mean annual increase rate of about 1.5% for the years 1999-2000, while the demand for the year 2000 was 753.000 tons. For the same year the national production ranged up to 825.000 tons. Life Cycle Assessment (LCA) is a relatively new, cutting edge environmental decision support tool recently standardised by the International Standardisation Organisation (ISO). LCA is an excellent tool for environmental management, as it provides important information about the environmental burdens associated to a product, a process or any human activity. In this study, a simplified LCA following the “cradle-to-gate” approach has been applied to identify the critical points of the flour production in Greece. The SimaPro software was used for analyzing the main inventory data and estimating the environmental impacts of the overall system (from wheat grain to flour production). The system investigated includes agricultural production of soft wheat, transportation, industrial milling and packaging of the flour. Energy use, material use and emissions were quantified and the main potential environmental effects were assessed. The application of fertilizers, transportation and electrical energy consumption were found to be the ‘hot spots’ for many, but not all, of the impact categories investigated and specific actions were proposed in the aim to improve the environmental profile of the final product.
90

An analysis of the management and economics of salmon aquaculture

Liu, Yajie 05 1900 (has links)
Salmon aquaculture can be a potential solution to bridge the gap between declining capture fisheries and increasing seafood demand. However, the environmental impacts it creates have generated criticism. The overall objectives of this dissertation are to examine the economic consequences of environmental issues associated with salmon aquaculture, and to explore policy implications and recommendations for reducing environmental impacts. These objectives are addressed in five main analyses. The growth of salmon aquaculture is analyzed based on farmed salmon production in the four leading producing countries and the sector as a whole. Analyses indicate that salmon aquaculture is unlikely to continue to grow at its current pace. A joint production function approach is used to estimate pollution abatement costs for the salmon aquaculture industry. Results reveal that pollution abatement costs vary among observations and models. On average, pollution abatement cost is estimated at 3.5% in terms of total farmed salmon production, and 6.5% in terms of total revenue of farmed salmon. The ecological and economic impacts of sea lice from salmon farms on wild salmon population and fisheries are also studied. Analyses suggest that these effects are minor when the sea lice induced mortality rate is below 20%, while they can be severe if the mortality is greater than 30%. Sea lice have greater ecological and economic impacts on pink salmon than on chum salmon. These effects are greater under a fixed exploitation rate than under a target escapement policy. The economic performance of open netcage and sea-bag production systems for salmon aquaculture is compared. Netcage systems appear to be more economically profitable than sea-bag systems when environmental costs are either not or only partially included. Sea-bag systems can be financially profitable only when the salmon they produce can achieve a price premium. Finally, policy implications are explored and recommendations are made for sustaining salmon aquaculture in a holistic manner based on the results from previous chapters. Technologies, economic-based instruments and more stringent environmental policies can be employed to reduce environmental impacts. However, there is no single solution to solve these environmental impacts, and a combination of policy options is needed.

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