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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.
281

Changes in the balance between water uses and availability in two Mediterranean hydrosystems : adaptation to climatic and anthropogenic changes / Equilibres entre usage et disponibilité en eau sur deux hydrosystèmes méditerranéens : adaptation aux changements climatiques et anthropiques

Fabre, Julie 07 December 2015 (has links)
La thèse propose une approche originale pour évaluer les évolutions à moyen terme des équilibres entre usages et ressources en eau à l’échelle de bassins versants. Un cadre de modélisation intégrant les dynamiques hydro-climatiques et des activités humaines ainsi que les liens entre demandes et ressources en eau a été développé et appliqué sur deux bassins d’échelles différentes et aux usages de l’eau contrastés : l’Hérault (2500 km2, France) et l’Ebre (85000 km2, Espagne). Les écoulements naturels ont été simulés avec un modèle hydrologique conceptuel et un modèle de gestion de barrage piloté par les demandes associées et les contraintes de gestion a été implémenté. Les demandes en eau municipal, industrielle et d'irrigation ont été estimées à partir de données socio-economiques, agronomiques et climatiques. Des débits environnementaux seuils, en-dessous desquels les prélèvements sont limités, ont été pris en compte. La chaîne de modélisation a été calée et validée sous les conditions anthropiques et hydro-climatiques non-stationnaires de 40 années passées, avant d’être appliquée sous quatre combinaisons de scénarios de changements climatiques et d’usages de l’eau, permettant ainsi de différencier les impacts climatiques et anthropiques. Des simulations climatiques de l’exercice CMIP5 ont été utilisées pour générer 18 scénarios climatiques à l’horizon 2050, et un scénario tendanciel des usages de l’eau a été proposé sur la base de tendances socio-écononomiques locales. La disponibilité en eau a été comparée à la demande à travers des indicateurs de fréquence et d’intensité de satisfaction. L'impact des scénarios climatiques sur la disponibilité et la demande en eau pourrait remettre en question les allocations et débits environnementaux envisagés pour les décennies à venir. Les limitations de prélèvements pourraient devenir pus fréquentes, et la pression anthropique sur les milieux aquatiques pourrait s'intensifier. Pour évaluer le potentiel d’adaptation aux changements climatiques, une analyse de sensibilité des indicateurs aux principaux facteurs d’évolution de la demande et de la gestion de barrages a été réalisée. L’efficacité et la robustesse de mesures individuelles varient entre les bassins et selon les nœuds de demande. Un scénario d’adaptation combinant différentes mesures a ensuite été testé. Ce scénario pourrait réduire sensiblement le stress hydriquel, cependant sa robustesse vis-à-vis des incertitudes climatiques pourrait être insuffisante. Afin d'atteindre un équilibre durable entre usages et ressources en eau et de réduire la vulnerabilité des usages de l'eau, une complémentarité doit être trouvée entre des études quantitatives à l'échelle de bassins versants, comme celle menée dans cette thèse, et des études locales de la vulnérablité socio-économique et des capacités d'adaptation. / This thesis proposes an original approach to assess multi-decadal changes in the balance between water use and availability in managed river basins. A modeling framework integrating human and hydro-climatic dynamics and accounting for linkages between resource and demand was developed and applied in two basins of different scales and with contrasted water uses: the Herault (2500 km2, France) and the Ebro (85000 km2, Spain) basins. Natural streamflow was evaluated using a conceptual hydrological model, and a demand-driven reservoir management model was designed to account for streamflow regulations from the main dams. Urban, industrial and agricultural water demands were estimated from socio-economic and agronomic and climatic drivers. Environmental flows were accounted for by defining streamflow thresholds under which water withdrawals were strictly limited. This framework was successfully calibrated and validated under non-stationary human and hydro-climatic conditions over a past period of 40 years before being applied under four combinations of climatic and water use scenarios to differentiate the impacts of climate- and human-induced changes on streamflow and water balance. Climate simulations from the CMIP5 exercise were used to generate 18 climate scenarios at the 2050 horizon and a trend water use scenario was built based on demographic and local socio-economic trends by the mid-21textsuperscript{st}century. Indicators comparing water supply to demand were computed. The impact of the tested climate projections on both water availability and demand could question the water allocations and environmental requirements currently planned for the coming decades. Water shortages for human use could become more frequent and intense, and the pressure on water resources and aquatic ecosystems could intensify. To assess the efficiency of potential adaptation measures under climate change scenarios, the sensitivity of water stress to variations in the main drivers of water demand and dam management was tested. The effectiveness and robustness of individual measures varied between the basins and within each basin. Finally an adaptation scenario combining different measures was tested in both basins, using the integrative modeling framework. This scenario led to encouraging results regarding the decrease of water stress. However, the adaptation strategies were shown to be insufficiently robust to climate change uncertainties. To achieve a sustainable balance between water availability and demand and reduce the vulnerability of water uses to climate change, a complementarity needs to be found between basin-scale studies of the water balance, such as the ones conducted in this thesis, and local assessments of vulnerability and adaptive capacity.
282

Analyse de cycle de vie conséquentielle appliquée aux ensembles bâtis / Consequential life cycle assessment applied to buildings

Roux, Charlotte 26 September 2016 (has links)
La construction et la réhabilitation des bâtiments et des quartiers induisent des dommages environnementaux de nature diverse (consommation de ressources, émissions de substances toxiques, atteintes aux écosystèmes). De plus, ces impacts peuvent être générés de manière indirecte (déchets radioactifs produits par la consommation d’électricité par exemple). D’où l’importance d’une approche d’évaluation environnementale holistique et multicritère. L’analyse de cycle de vie (ACV) correspond à ce cahier des charges. Cette méthode a été appliquée pour évaluer la contribution d’un bâtiment ou d’un quartier à un ensemble de thématiques environnementales (au contraire d’un outil monocritère comme le bilan carbone) et ce sur l’intégralité du cycle de vie : fabrication des matériaux, construction, utilisation, rénovation, démolition et traitement des déchets. Cette méthode peut être utilisée à différente étapes d’un projet : définition d’objectifs de programme, aide à la conception, aide à la gestion, aide à la rénovation, aide à la stratégie de déconstruction.Cette thèse s’inscrit dans le cadre de l’application de l’ACV à l’éco-conception des ensembles bâtis, de la maison individuelle jusqu’au quartier multifonctionnel. L’objectif est d’améliorer la qualité de l’aide à la décision fournie par les outils d’éco-conception en matière de réalisme et de précision des études.Trois axes de travail en interaction ont été explorés :- Conséquentiel : Quels apports conceptuels et pratiques peut-on mettre en œuvre sur la base des recherches sur l’ACV conséquentielle ?- Dynamique : Comment intégrer les interactions dynamiques entre le parc bâti et son système d’arrière plan, en particulier le système électrique?- Prospectif : Comment tenir compte de la longue durée de vie des ensembles bâtis ?La thèse propose premièrement un nouveau cadre conceptuel pour l’évaluation des projets de conception et de réhabilitation s’inspirant des récents travaux méthodologiques sur l’ACV conséquentielle. L’application pratique de cette nouvelle approche « conséquentielle-projet » nécessite la production de connaissances mobilisant l’ACV dynamique et l’ACV prospective.Concrètement, la thèse propose une modélisation dynamique du fonctionnement du système électrique dans un cadre « type » affranchi des aléas climatiques et économiques. Le modèle sert de base au développement de méthodes d’évaluation originales des impacts de l’électricité : une méthode dynamique moyenne et une méthode marginale. Ces méthodes améliorent la précision d’une étude d’analyse de cycle de vie, quel que soit l’objectif (certification ou écoconception) et l’approche méthodologique associée (attributionnelle ou conséquentielle-projet).La thèse propose ensuite l’intégration de scénarios prospectifs adaptés à l’étude des bâtiments et des quartiers. Celle-ci associe les recherches en prospective énergétique menées à l’échelle nationale et les recherches concernant l’impact du changement climatique sur le comportement thermique des bâtiments. Les effets conjoints de ces deux déterminants sont évalués au sein d’une approche originale et intégrée.La thèse explore également la question du changement d’échelle du bâtiment vers le quartier. Les cas du transport des occupants et du traitement des déchets sont analysés au prisme de l’approche « conséquentielle-projet ». Une méthodologie de couplage des outils de simulation transport au niveau local et de l’ACV est notamment proposée. Elle constitue un premier pas vers un couplage interdisciplinaire des outils d’analyse des projets urbains.Les différents développements méthodologiques sont finalement appliqués à une étude de cas afin d’analyser et d’interpréter l’effet des nouvelles approches sur l’aide à la décision fournie par les outils d’écoconception. / Environmental impacts induced by urban projects concern various topics (resources, health, biodiversity). Some are indirect impacts (for instance radioactive waste generated by electricity consumption). This calls for a holistic and multicriteria approach such as Life-Cycle-Analysis (LCA) in order to evaluate environmental performance of construction or retrofitting projects. Considering cradle to grave impacts this method is used at different project phases: program objectives, design aid, management strategies evaluation, retrofitting project, dismantling, and waste management.The thesis lies in the framework of life-cycle analysis applied to urban project design, from individual houses up to multifunctional neighborhoods. The underlying objective is to improve relevance and accuracy of the decision aid provided by LCA-based design tools.Three interacting topics have been investigated:- Consequential assessment: How can the results of current research on consequential LCA be implemented in Building LCA?- Dynamic: How to integrate dynamic interaction between buildings and the background system, mainly the electricity grid?- Prospective: How to take into account the long life span of buildings and urban districts?The dissertation firstly suggests a new framework for evaluating construction or retrofitting project, grounded in consequential LCA. The practical application of this consequential-project approach requires knowledge generation on dynamic and prospective LCA.A dynamic model of the electricity system has been developed. From this model, a reference operation year of the electricity system has been determined, mitigating climatic and economical hazards of real years. Based on this model, a dynamic average approach and a marginal approach are defined to assess life-cycle impacts of electricity consumption. These developments improve the accuracy of LCA independently of the chosen modeling approach, consequential or attributional.The prospective dimension is explored, through scenarios development. The suggested scenarios bring together national energy prospective research and global warming effects on buildings thermal behavior. The combined effects are evaluated using a novel and integrated approach.The thesis then addresses the scale issue when moving from building to district projects. Following the consequential-project approach principles, the focus is made on integrating daily transport and domestic waste models in LCA of urban projects. A method to combine local transport simulation models and building LCA is suggested. It establishes a first step towards integrated multidisciplinary assessment of urban projects.The developed approaches and methodologies are finally tested on a case study.
283

Water Supply of Accra, with Emphasis on Sachet Water.

Diawuo, Felix January 2011 (has links)
This project seeks to assess the impact of the sachet water industry on the health, socio-economic and the environmental situation of the inhabitants of Accra, the capital city of Ghana. In addressing the situation, the driving forces which have fuelled the shift of consum-er taste from the normal tap water and the traditional hand-tied-ice water products to the plastic sachet water (commonly known in as "Pure Water") are identified. Lack of access to continuous flow of improved water and the perceived poor quality of the urban water supply system as results of poor management structure are identified as some of the factors for the shift in consumers’ taste for plastic sachet and bottled drinking water. The quality of the plastic sachet is also assessed through the review of previous research results. These are confirmed by laboratory analysis of about six brands of plastic sachet water and two brands bottled drinking water. The laboratory analysis carried out assessed the microbial, physical and chemical quality of the various samples. To assess the health impacts of the products, the results from the analysis are compared with WHO guideline values and other international guideline values. Questionnaires are also administered to ascertain the socio-economic impacts of the products on the life of the young men and women as well sachet water manufacturers. From this, some measures are suggested as to how to mitigate the activities of the sachet water business to reduce its negative effects on the health, the environment and the socio-economic status of the inhabitants of the city.
284

Politiques publiques et Coupe du monde de football 2014 au Brésil : des espoirs aux héritages locaux / Public Policy and 2014 Football World Cup Brazil : from hopes to local heritage

Castilho, César 07 November 2016 (has links)
Cette étude porte sur l’analyse des impacts sociaux de la Coupe du monde de football FIFA 2014 au Brésil, pays émergent, spécifiquement dans quatre villes d’accueil : Manaus, Recife, Rio de Janeiro et Belo Horizonte. La démarche, s’appuyant sur les principes de la recherche qualitative, cherche à comprendre les processus de décision des organisateurs de l’événement – tant au niveau national que local – et la mise en place des politiques publiques liées aux groupes sociaux défavorisés du pays. Il s’agit d’analyser à la fois l’importance donnée par les responsables aux questions socio-économiques et le rôle joué par les habitants dans l’accueil de l’événement.Le corpus rassemble 63 entretiens [50 acteurs interviewés], 48 séquences d’observation, 87 photographies et des documents publiés [dossiers officiels, articles de journaux, sites officiels, rapports administratifs]. La recherche de terrain a été réalisée entre les années 2013 et 2015 de sorte à observer la préparation de l’événement et les impacts à moyen terme.En analysant les politiques publiques adoptées, la recherche a montré un manque de dialogue entre les organisateurs et la population locale, notamment les groupes sociaux défavorisés, en ce qui concerne les processus de décision et les héritages réels à court et à moyen termes. En général, les responsables ont mis en valeur les aspects tangibles – travaux urbains et nouvelles arènes – au détriment des changements socio-sportifs majeurs. En revanche, les habitants locaux ont joué un rôle crucial dans la réussite de la Coupe du monde au travers de leur accueil des visiteurs et de leur manière singulière de fêter le football. En outre, compte tenu des manifestations survenues en 2013 et 2014, un nouveau mouvement d’opposition aux grands événements sportifs a vu le jour mettant à l’épreuve les aspects économiques soulignés par les institutions organisatrices. / This research focuses on the analysis of social impacts related to the 2014 FIFA World Cup in Brazil, an emerging country, specifically in four host cities : Manaus, Recife, Rio de Janeiro and Belo Horizonte. This approach, based on the principles of qualitative research, seeks to understand the decision process of event organizers – on local and international levels – and the implementation of public policies targeting disadvantaged social groups in the country. This research aims to analyze both the level of consideration given to social issues by the event’s organizing committee; as well as the role played by the host cities’ residents in the reception of visitors.The corpus brings together 63 interviews [50 actors interviewed], 48 observation grids, 87 photographs and published documents [official records, newspapers articles, official websites, business reports]. Field research was carried out between 2013 and 2015 in order to observe the preparation of the event and the medium-term impacts.By analysing public policies, the research showed a lack of dialogue between the organizers and the local population, especially the deprived social groups, regarding the decision process and the real legacies in the short and medium terms. In general, officials have highlighted the tangibles aspects – urban projects and new arenas – at the expense of major social and sporting changes. Conversely, local residents have played a crucial role in the success of the 2014 World Cup through their visitor reception and unique way of celebrating football. Furthermore, given the events that occurred in 2013 and 2014, a new opposition movement against mega sport events was established - challenging the economic aspects highlighted by the organizing institutions.
285

Modeling Of The Biomass Power Generation And Techno-Economic Analysis

Methuku, Shireesha 11 December 2009 (has links)
Biomass is one of the renewable energy sources being used widely for power generation. This research work includes developing a comprehensive model for a biomass based power generation system as well as analyzing the technical, economical, and environmental impacts. The research objectives include modeling of the system, stability studies, and sensitivity analysis using MATLAB/Simulink. A mathematical model for the gas turbine has been developed and successfully interconnected with the distribution network. Transient stability of the power system has been carried out for four bus and six bus test case systems. Maximum rotor speed deviation, oscillation duration, rotor angle, and mechanical power have been taken as the stability indicators to analyze the system characteristics. Additionally, the sensitivity of the system to the changes of gas turbine parameters has been investigated under balanced and unbalanced fault scenarios. The economical and environmental impacts of the biomass have been analyzed using HOMER software developed by the National Renewable Energy Laboratory (NREL). The net present cost of the four biomass resources namely agricultural resources, forest residues, animal waste, and energy crops were obtained and the comparison of the costs of the biomass fuels as well as the diesel have been carried out. To investigate the environmental impact, carbon emissions of the different biomass fuels have been explored using HOMER.
286

Disruption in place attachment: Insights of young Aboriginal adults on the social and cultural impacts of industrial development in northern Alberta

Spyce, Tera Unknown Date
No description available.
287

Disruption in place attachment: Insights of young Aboriginal adults on the social and cultural impacts of industrial development in northern Alberta

Spyce, Tera 11 1900 (has links)
People living in the north have been and will continue to be affected by increasing exploration and exploitation of the region's natural resources. To understand the human impacts a qualitative approach and sense of place, place attachment, and disruption in place theories were used to analyze the experiences of young Aboriginal adults in a Dene Tha' community in northwestern Alberta. The major finding of this study was that the young people developed deep attachments to their place; however, environmental, social, and cultural changes have altered life here and as a consequence many of the young people no longer want to remain living in their community. The results suggest that the Dene Tha' are being gradually displaced and their homeland is becoming increasingly unable to sustain them or their culture. The findings also indicate that gradual environmental deterioration can lead to profound social and cultural changes that should be considered before land use decisions are made. / Rural Sociology
288

Regional Hydrologic Impacts Of Climate Change

Rehana, Shaik 11 1900 (has links) (PDF)
Climate change could aggravate periodic and chronic shortfalls of water, particularly in arid and semi-arid areas of the world (IPCC, 2001). Climate change is likely to accelerate the global hydrological cycle, with increase in temperature, changes in precipitation patterns, and evapotranspiration affecting the water quantity and quality, water availability and demands. The various components of a surface water resources system affected by climate change may include the water availability, irrigation demands, water quality, hydropower generation, ground water recharge, soil moisture etc. It is prudent to examine the anticipated impacts of climate change on these different components individually or combinedly with a view to developing responses to minimize the climate change induced risk in water resources systems. Assessment of climate change impacts on water resources essentially involves downscaling the projections of climatic variables (e.g., temperature, humidity, mean sea level pressure etc.) to hydrologic variables (e.g., precipitation and streamflow), at regional scale. Statistical downscaling methods are generally used in the hydrological impact assessment studies for downscaling climate projections provided by the General Circulation Models (GCMs). GCMs are climate models designed to simulate time series of climate variables globally, accounting for the greenhouse gases in the atmosphere. The statistical techniques used to bridge the spatial and temporal resolution gaps between what GCMs are currently able to provide and what impact assessment studies require are called as statistical downscaling methods. Generally, these methods involve deriving empirical relationships that transform large-scale simulations of climate variables (referred as the predictors) provided by a GCM to regional scale hydrologic variables (referred as the predictands). This general methodology is characterized by various uncertainties such as GCM and scenario uncertainty, uncertainty due to initial conditions of the GCMs, uncertainty due to downscaling methods, uncertainty due to hydrological model used for impact assessment and uncertainty resulting from multiple stake holders in a water resources system. The research reported in this thesis contributes towards (i) development of methodologies for climate change impact assessment of various components of a water resources system, such as water quality, water availability, irrigation and reservoir operation, and (ii) quantification of GCM and scenario uncertainties in hydrologic impacts of climate change. Further, an integrated reservoir operation model is developed to derive optimal operating policies under the projected scenarios of water availability, irrigation water demands, and water quality due to climate change accounting for various sources of uncertainties. Hydropower generation is also one of the objectives in the reservoir operation. The possible climate change impact on river water quality is initially analyzed with respect to hypothetical scenarios of temperature and streamflow, which are affected by changes in precipitation and air temperature respectively. These possible hypothetical scenarios are constructed for the streamflow and river water temperature based on recent changes in the observed data. The water quality response is simulated, both for the present conditions and for conditions resulting from the hypothetical scenarios, using the water quality simulation model, QUAL2K. A Fuzzy Waste Load Allocation Model (FWLAM) is used as a river water quality management model to derive optimal treatment levels for the dischargers in response to the hypothetical scenarios of streamflow and water temperature. The scenarios considered for possible changes in air temperature (+1 oC and +2 oC) and streamflow (-0%, -10%, -20%) resulted in a substantial decrease in the Dissolved Oxygen (DO) levels, increase in Biochemical Oxygen Demand (BOD) and river water temperature for the case study of the Tunga-Bhadra River, India. The river water quality indicators are analyzed for the hypothetical scenarios when the BOD of the effluent discharges is at safe permissible level set by Pollution Control Boards (PCBs). A significant impairment in the water quality is observed for the case study, under the hypothetical scenarios considered. A multi-variable statistical downscaling model based on Canonical Correlation Analysis (CCA) is then developed to downscale future projections of hydro¬meteorological variables to be used in the impact assessment study of river water quality. The CCA downscaling model is used to relate the surface-based observations and atmospheric variables to obtain the simultaneous projection of hydrometeorological variables. Statistical relationships in terms of canonical regression equations are obtained for each of the hydro-meteorological predictands using the reanalysis data and surface observations. The reanalysis data provided by National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) are used for the purpose. The regression equations are applied to the simulated GCM output to model future projections of hydro-meteorological predictands. An advantage of the CCA methodology in the context of downscaling is that the relationships between climate variables and the surface hydrologic variables are simultaneously expressed, by retaining the explained variance between the two sets. The CCA method is used to model the monthly hydro-meteorological variables in the Tunga-Bhadra river basin for water quality impact assessment study. A modeling framework of risk assessment is developed to integrate the hydro¬meteorological projections downscaled from CCA model with a river water quality management model to quantify the future expected risk of low water quality under climate change. A Multiple Logistic Regression (MLR) is used to quantify the risk of Low Water Quality (LWQ) corresponding to a threshold DO level, by considering the streamflow and water temperature as explanatory variables. An Imprecise Fuzzy Waste Load Allocation Model (IFWLAM) is adopted to evaluate the future fractional removal policies for each of the dischargers by including the predicted future risk levels. The hydro-meteorological projections of streamflow, air temperature, relative humidity and wind speed are modeled using MIROC 3.2 GCM simulations with A1B scenario. The river water temperature is modeled by using an analytical temperature model that includes the downscaled hydro-meteorological variables. The river water temperature is projected to increase under climate change, for the scenario considered. The IFWLAM uses the downscaled projections of streamflow, simulated river water temperature and the predicted lower and upper future risk levels to determine the fraction removal policies for each of the dischargers. The results indicate that the optimal fractional removal levels required for the future scenarios will be higher compared to the present levels, even if the effluent loadings remain unchanged. Climate change is likely to impact the agricultural sector directly with changes in rainfall and evapotranspiration. The regional climate change impacts on irrigation water demands are studied by quantifying the crop water demands for the possible changes of rainfall and evapotranspiration. The future projections of various meteorological variables affecting the irrigation demand are downscaled using CCA downscaling model with MIROC 3.2 GCM output for the A1B scenario. The future evapotranspiration is obtained using the Penman-Monteith evapotranspiration model accounting for the projected changes in temperature, relative humidity, solar radiation and wind speed. The monthly irrigation water demands of paddy, sugarcane, permanent garden and semidry crops quantified at nine downscaling locations covering the entire command area of the Bhadra river basin, used as a case study, are projected to increase for the future scenarios of 2020-2044, 2045-2069 and 2070-2095 under the climate change scenario considered. The GCM and scenario uncertainty is modeled combinedly by deriving a multimodel weighted mean by assigning weights to each GCM and scenario. An entropy objective weighting scheme is proposed which exploits the information contained in various GCMs and scenarios in simulating the current and future climatology. Three GCMs, viz., CGCM2 (Meteorological Research Institute, Japan), MIROC3.2 medium resolution (Center for Climate System Research, Japan), and GISS model E20/Russell (NASA Goddard Institute for Space Studies, USA) with three scenarios A1B, A2 and B1 are used for obtaining the hydro-meteorological projections for the Bhadra river basin. Entropy weights are assigned to each GCM and scenario based on the performance of the GCM and scenario in reproducing the present climatology and deviation of each from the projected ensemble average. The proposed entropy weighting method is applied to projections of the hydro-meteorological variables obtained based on CCA downscaling method from outputs of the three GCMs and the three scenarios. The multimodel weighted mean projections are obtained for the future time slice of 2020-2060. Such weighted mean hydro-meteorological projections may be further used into the impact assessment model to address the climate model uncertainty in the water resources systems. An integrated reservoir operation model is developed considering the objectives of irrigation, hydropower and downstream water quality under uncertainty due to climate change, uncertainty introduced by fuzziness in the goals of stakeholders and uncertainty due to the random nature of streamflow. The climate model uncertainty originating from the mismatch between projections from various GCMs under different scenarios is considered as first level of uncertainty, which is modeled by using the weighted mean hydro-meteorological projections. The second level of uncertainty considered is due to the imprecision and conflicting goals of the reservoir users, which is modeled by using fuzzy set theory. A Water Quantity Control Model (WQCM) is developed with fuzzy goals of the reservoir users to obtain water allocations among the different users of the reservoir corresponding to the projected demands. The water allocation model is updated to account for the projected demands in terms of revised fuzzy membership functions under climate change to develop optimal policies of the reservoir for future scenarios. The third level of uncertainty arises from the inherent variability of the reservoir inflow leading to uncertainty due to randomness, which is modeled by considering the reservoir inflow as a stochastic variable. The optimal monthly operating polices are derived using Stochastic Dynamic Programming (SDP), separately for the current and for the future periods of 2020-2040 and 2040-2060 The performance measures for Bhadra reservoir in terms of reliability and deficit ratios for each reservoir user (irrigation, hydropower and downstream water quality) are estimated with optimal SDP policy derived for current and future periods. The reliability with respect to irrigation, downstream water quality and hydropower show a decrease for 2020-2040 and 2040-2060, while deficit ratio increases for these periods. The results reveal that climate change is likely to affect the reservoir performance significantly and changes in the reservoir operation for the future scenarios is unable to restore the past performance levels. Hence, development of adaptive responses to mitigate the effects of climate change is vital to improve the overall reservoir performance.
289

Les modes d'organisation de la production chez les firmes étrangères et leurs impacts sur les économies agricoles locales : le cas du secteur maraîcher au Maroc / The production organization modes of foreign firms and their impacts on the local agricultural economics : the case of the vegetable sector in Morocco

Bensalk, Sana 26 June 2013 (has links)
Dans un environnement marqué par une forte pression sur les ressources locales, des firmes étrangères à capitaux européens se sont implantées dans le secteur maraîcher au Maroc dans un contexte de recherche de coûts plus compétitifs. Notre étude propose une analyse conjointe des modes d'organisation de la production chez les firmes étrangères et de leurs impacts sur les économies agricoles locales. D'un point de vue théorique, cette analyse s'appuie sur la théorie des coûts de transaction, la littérature relative à l'économie et le bien-être des ménages et le modèle de Jovanovic relatif à la croissance de la firme. D'un point de vue empirique, les données primaires ont été collectées grâce à une enquête qualitative auprès des firmes étrangères et une enquête quantitative auprès des ménages agricoles locaux au Maroc. Notre étude révèle une diversité des modes d'organisation chez les opérateurs étrangers selon les spécificités de la production et de la commercialisation. Ces opérateurs ont différents niveaux d'implication en amont. En effet, ils ont élaboré diverses relations directes avec des ménages agricoles locaux via les marchés des inputs et des outputs. Des ménages locaux ont développé un salariat auprès des IDE dans des logiques d'accumulation de revenus et de minimisation de risques liés à leurs faibles revenus agricoles. Ces ménages ont affecté les revenus tirés de ces emplois à un réinvestissement dans le secteur agricole ou à une amélioration de leur bien-être. Nous montrons que les liens directs des firmes étrangères avec les ménages locaux via le marché des outputs ont des effets positifs sur la croissance de la SAU des exploitations domestiques, contrairement à leurs liens via le marché du travail et celui du foncier. Nos résultats confirment les prédictions théoriques du modèle de Jovanovic. La présence des IDE a été associée à une diffusion des effets spillovers horizontaux positifs sur la croissance de la SAU des exploitations locales, situées à proximité des IDE, mieux dotées en technologies et exportatrices. Le capital social de ménages locaux et leur zone de localisation ont joué un rôle important dans la croissance de leurs ressources foncières. Pour mieux comprendre cette dynamique, il est indispensable d'analyser les impacts des firmes étrangères sur l'évolution de la force du travail des exploitations agricoles domestiques. / Foreign firms with European capital in the vegetable sector in Morocco are developing in an environment marked by strong pressure on local resources, in the research of more competitive costs. Our study proposes a joint analysis of the production organization modes of foreign firms and their impact on the local agricultural economics. For our theoretical approach, this analysis is based on the theory of transaction costs, the literature on the economics and the welfare of households and the Jovanovic's model of firm growth. For our empirical approach, the primary data were collected through a qualitative survey with foreign firms and a quantitative survey with local farm households in Morocco. Our study reveals a diversity of production organization modes of foreign operators depending on the production and marketing specificities. These operators have different levels of implication in upstream. In fact, they have various direct relationships with local farm households through the inputs and outputs markets. Local households developed employments within FDI in the logics of income accumulation and risks minimizing related to their low farm incomes. These households affected income of these jobs to a reinvestment in agriculture or an improvement of their welfare. We show that the direct links of foreign firms with local households through the outputs market have positive effects on the growth of the domestic farms physical size, unlike their links through the labor and land markets. Our results confirm the theoretical predictions of the Jovanovic's model. The presence of FDI was associated with a diffusion of positive horizontal spillovers effects on the growth of local farms, located near the foreign firms, better endowed in technology and exporting firms. The social capital of local households and their location area have an important role in the growth of their land resources. Our study should be completed by impacts analysis of foreign firms on the labor force evolution of domestic farms.
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Les impacts des expositions internationales et universelles sur les dynamiques métropolitaines des villes de la péninsule ibérique : Séville, Lisbonne et Saragosse

Castet, Jean-Bernard 22 November 2011 (has links)
Plus que d’autres types de grands évènements, les expositions internationales et universelles contribuent à changer le visage des villes organisatrices. Résolument comparative, cette analyse se propose de travailler sur trois expositions ayant eu lieu ces dernières décennies dans la péninsule ibérique. Les exemples de Séville, Lisbonne et Saragosse, villes de taille comparable et de contraintes similaires permettent de mieux évaluer les impacts de cette catégorie de grand évènement à la fois aux échelles métropolitaine, régionale et nationale. Au-delà de cet apport, l’objectif est également de dégager des éléments permettant d’analyser les bénéfices et les limites de ce type de grand évènement atour de quatre principaux items : l’impact urbain, l’impact économique, l’impact en termes d’image et l’impact sur les acteurs. Cette thèse vise à comprendre ce que ces expositions récentes ont apporté à ces villes, à la fois sur le court et le long terme, en analysant successivement les temps de la projection, de la réalisation et de la reconversion des sites d’exposition Ce travail démontre ainsi que les expositions, au-delà des réflexions postulant pour leur déclin progressif et inexorable, sont en fait de véritables accélérateurs du développement urbain et du processus de métropolisation. Mieux préparées et utilisées, elles pourraient donc être appelées aujourd’hui plus qu’hier encore à transformer les villes, notamment pour leur permettre de se mettre en cohérence avec les critères d’un développement métropolitain plus durable. / More than other major events, universal and international exhibitions contribute to revamp host cities. Associated to a comparative method, this analysis intends to study the three exhibitions which took place those ultimate decades in the Iberian peninsula. The examples of Sevilla, Lisbon and Saragossa, comparable towns with similar issues allow to evaluate the impacts of this kind of major events considering the metropolitan, regional and national scales. Beyond this contribution, the goal is to underline the elements that allow to analyse the benefits and the limits of that type of major events given four principal elements: urban impact, economical impact, representative impact and social impact. This thesis aims at understanding the exhibition’s contribution to those towns, on a medium and a long term, considering the time of projection, realization and reconversion of exhibitions spots.This work also demonstrates that exhibitions, beyond the assumption of a progressive and inexorable decline, are real boosters for urban development and metropolisation process. Better prepared and used, exhibitions could be involved now more than ever in cities’ transformation, particularly to respect the criteria of a more sustainable metropolitan development.

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