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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.
31

Custo social de oportunidade na trajet?ria de acesso ao ensino superior: o caso dos ingressantes na UFRN nos vestibulares de 2006 a 2010

Oliveira, Ridalvo Medeiros Alves de 30 August 2011 (has links)
Made available in DSpace on 2014-12-17T14:36:31Z (GMT). No. of bitstreams: 1 RidalvoMAO_TESE.pdf: 3012875 bytes, checksum: f4ffef2e215903a0c0f94266c9f9e251 (MD5) Previous issue date: 2011-08-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Access is a problem of higher education in Brazil that has existed since the formalization of this has occurred since the installation of the Portuguese court in Brazil in 1808. Only 10% of young people between 18 and 24 years of age attending this level of education in 2000, arriving in 2010 just 15%, far from that determined the National Education Plan in 2001, triple that percentage by the year 2010. In addition, a majority of seats of public HEIs is populated by students from the private network, especially in high-demand courses. In this context, this study aims to identify the costs related to the trajectories of students who were successful in the vestibular UFRN editions from 2006 to 2010. Presents an overview of higher education in Brazil, a brief history of vestibular, as well as new forms of access, and some of the policies to expand such access, highlighting the argument Inclusion UFRN. Focusing on the theme of the paper presents the concepts of opportunity costs and social. After collecting data through a questionnaire and consultation of databases COMPERVE was developed to search for a descriptive and analytical, with the participation of 3,995 students, of whom 1642 (41.1%) had completed secondary education in schools public, and 2,078 (52%) in private schools. The profile indicates that 90% are single, about 50% are 21 years of age, are white and female. In the course of preparation for college entrance exams, 80% chose the course during or after completion of the last year of high school, and almost 70% said they had started preparing at that time. Findings related to the costs involved with this preparation indicate that, in most cases there were school fees and disbursements and workshops, and the purchase of books and other materials, with parents primarily responsible for this cost, the amount disbursed each month was up $ 300 for 64% of respondents and only 7% of them exceeded $ 1,000, the major non-financial costs were characterized by the following resignations: job opportunities (24%) or temporary work (20%) courses of languages (26%), leisure activities (48%), leisure travel (43%), and parties and / or shows (54%). Of social investments by the government, stand out in the tax waiver scholarships for study in private institutions, grant exemption from the registration fee of vestibular, the preparatory courses UFRN, and seminars by COMPERVE / UFRN with networks of high school. From the junction of the opportunity costs (private costs) and social costs (public costs), a new concept: the social opportunity cost, which measures the combined efforts of families and government to finance the opportunity to access higher education of an individual. This concept can and should be incorporated as a strategic vector for the sake of democratic university, which reflects the social model that is sought / O acesso ? um problema do ensino superior no Brasil que existe desde a formaliza??o deste, ocorrida ap?s a instala??o da corte portuguesa no pa?s, em 1808. Somente 10% dos jovens entre 18 e 24 anos de idade frequentavam esse n?vel de ensino no ano 2000, chegando em 2010 a apenas 15%, muito distante do que determinava o Plano Nacional de Educa??o em 2001: triplicar aquele percentual at? o ano 2010. Al?m disso, a maioria das vagas das IES p?blicas ? preenchida por alunos provenientes da rede privada, principalmente nos cursos de alta demanda. Nesse contexto, o presente estudo objetiva identificar os custos relacionados com as trajet?rias dos estudantes que obtiveram sucesso no vestibular da UFRN nas edi??es de 2006 a 2010. Apresenta uma retrospectiva do ensino superior no Brasil, um breve hist?rico do vestibular, bem como das novas formas de acesso, e algumas das pol?ticas de amplia??o desse acesso, destacando o Argumento de Inclus?o da UFRN. Focando o tema central do trabalho, s?o apresentados os conceitos de custos de oportunidade e sociais. Os dados dessa pesquisa, de car?ter descritivo e anal?tico, foram coletados por meio de um question?rio eletr?nico e de consultas aos bancos de dados da COMPERVE, com a participa??o de 3.995 alunos, dos quais 1.642 (41,1%) cursaram o ensino m?dio em escolas da rede p?blica, e 2.078 (52%) em escolas da rede privada. O perfil indica que 90% s?o solteiros; cerca de 50% tem at? 21 anos de idade, s?o de cor branca e do sexo feminino. Na trajet?ria de prepara??o para o vestibular, 80% escolheram o curso durante ou ap?s a conclus?o do ?ltimo ano do ensino m?dio, e quase 70% afirmaram ter iniciado a prepara??o nessa mesma ?poca. Descobertas relacionadas aos custos envolvidos com essa prepara??o apontam que: na maioria dos casos houve desembolsos com mensalidades escolares e cursinhos, e com a aquisi??o de livros e outros materiais, sendo os pais os principais respons?veis por esse custeio; o valor desembolsado mensalmente foi de at? R$ 300 para 64% dos respondentes e, para apenas 7% destes ultrapassou R$ 1.000; os principais custos n?o financeiros se caracterizaram pelas seguintes ren?ncias: oportunidades de empregos (24%) ou trabalhos tempor?rios (20%); frequentar cursos de idiomas (26%); atividades de lazer (48%); viagens de lazer (43%); e festas e/ou shows (54%). Dos investimentos sociais por parte do governo, destacam-se a ren?ncia fiscal na concess?o de bolsas de estudo em IES privadas, a concess?o de isen??o de taxa de inscri??o do vestibular, os cursinhos preparat?rios da UFRN, e a realiza??o de semin?rios pela COMPERVE/UFRN com as redes de ensino m?dio. A partir da jun??o dos custos de oportunidade (custos privados) com os custos sociais (custos p?blicos), surge um novo conceito: o de custo social de oportunidade, que mede o esfor?o conjunto das fam?lias e do governo para o financiamento da oportunidade de acesso ao ensino superior de um indiv?duo. Esse conceito pode e deve ser incorporado como um vetor estrat?gico para a causa da universidade democr?tica, que reflete o modelo de sociedade que se busca
32

Social Cost-Vehicle Routing Problem in Post-Disaster Humanitarian Logistics

Sadeghi, Azadeh 10 September 2021 (has links)
No description available.
33

Multi-objective optimization strategies for design and deployment of hydrogen supply chains / Stratégies d'optimisation multi-objectif pour la conception et le déploiement de chaînes logistiques hydrogène

Ochoa Robles, Jesus 05 July 2018 (has links)
L'hydrogène est l'un des vecteurs énergétiques les plus prometteurs dans la recherche d'un mix énergétique plus durable. Plusieurs études et feuilles de route ont été réalisées sur le potentiel d'une économie « hydrogène » et ont identifié que même si de nombreuses technologies requisessont déjà disponibles aujourd'hui, le déploiement d'infrastructures hydrogène constitue la tâche la plus difficile de son développement, dont la mesure où on doit atteindre des coûts compétitifs et avoir l'acceptation du marché. La conception de la chaîne logistique de l’hydrogène (HSC), enparticulier à des fins de mobilité, implique une série de décisions importantes à différents niveaux (sources d'énergie, production, transport et stockage) et peut être considérée comme un problème multi-échelle et multi-période avec plusieurs parties prenantes. L'objectif de ce travail est de proposer un cadre méthodologique pour aborder le problème de conception de la HSC de manière complémentaire au travail proposé dans le travail de doctorat de (Sofia de Leon Almaraz, 2014) dans lequel une formulation multi-objectif a été mise en œuvre via la méthodologie - contrainte pour obtenir le front de Pareto, en optimisant trois objectifs en même temps : le coût journalier total, le potentiel de réchauffement global et un indice de risque de sécurité. Une analyse de sensibilité basée sur un plan d'expérience en utilisant les méthodes de plan factoriel et surface de réponse a été réalisée pour identifier les principaux paramètres (facteurs) et leur interaction affectant le critère économique, soit le coût journalier total (TDC) (réponse), englobant les coûts capitaux et opérationnels. Cette analyse de sensibilité souligne que la demande est de loin le paramètre le plus important qui conditionne fortement le critère TDC, de sorte que davantage d'efforts sont nécessaires pour modéliser l'incertitude de la demande de façon homogène. Dans la formulation initiale de la conception de la HSC, la taille du problème liée au nombre de variables binaires conduit souvent à des difficultés pour résoudre le problème. Dans ce travail, le potentiel des algorithmes génétiques (GA) via une variante de NSGA-II est exploré pour faire face à la formulation multi-objectif, afin de produire automatiquement le front de Pareto. La formulation du modèle a ensuite été étendue pour tenir compte de l'incertitude de la demande, ce qui donne plus de robustesse à l'approche proposée. Deux études de cas soutiennent cette analyse : d'abord au niveau régional, les résultats de la conception de la HSC pour l'ancienne région Midi-Pyrénées obtenus avec les deux modèles sont comparés. Les solutions obtenues par GA présentent le même ordre de grandeur que celles obtenues avec MILP (Programmation Linéaire en Nombres Entiers) dans le problème mono-critère, mais de meilleures solutions de compromis sont produites dans la formulation multi-objectif et des résultats plus flexibles sont obtenues avec la modélisation de l’incertitude de demande. Puis l’écosystème aéroportuaire, Tarbes-Lourdes, a été étudié : l'infrastructure aéroportuaire est une étude de cas intéressante, car un aéroport est une source d'émissions qui affectent le climat à cause des émissions générées par les activités faites à l'intérieur et à l'extérieur du périmètre de l'aéroport, liées à l’opération et utilisation de l’aéroport. Enfin, une analyse post-optimale sur une solution de compromis de la HSC est réalisée sur la base d'une évaluation sociale, via deux analyses coûts-bénéfices (CBA) d'un point de vue social (SCBA) et gouvernemental (subventions et taxes), montrant que l'incorporation d'externalités aide à financer une proportion importante des coûts. L'approche SCBA pour le déploiement de l'hydrogène intègre les avantages sociétaux induits à travers la réduction des émissions de gaz à effet de serre, la réduction de la pollution atmosphérique mais aussi les coûts sociaux par l'augmentation de la consommation de platine. / Hydrogen is one of the most promising energy carriers in the quest for a more sustainable energy mix. Several studies and roadmaps have been carried out about the potential of a « hydrogen » economy and have identified that even if many of the required technologies are already available today, the deployment of hydrogen infrastructures constitutes the most challenging task for its development, so as to achieve competitive costs and mass market acceptance. The design of a hydrogen supply chain (HSC), in particular for mobility purpose, involves a series of important decisions at different levels, i.e. energy sources, production, transportation and storage and can be viewed as a multi-echelon, multi-objective and multi-period problem with multiple stakeholders. The objective of this work is to propose a methodological framework to tackle the HSC design problem in a complementary manner to the work proposed in the PhD work of (Sofia de Leon Almaraz, 2014) in which a multi-objective formulation was implemented via the -constraint method to generate the Pareto front, optimising three objectives at the same time, total daily cost, global warming potential and a safety risk index. A sensitivity analysis based on a design of experiments through the Factorial Design and Response Surface methods was carried to identify the major parameters (factors) and their interaction affecting the economic criterion, i.e., the total daily cost (TDC) (response), encompassing capital and operational expenditures. This sensitivity analysis highlights that the demand is by far the most significant parameter that strongly conditions the TDC criterion so that more effort is needed to model demand uncertainty consistently in HSC design, especially since a long horizon time is considered for hydrogen deployment. Besides, in the initial formulation of HSC design, the size of the problem related to the number of binary variables often leads to difficulties for problem solution. In this work, the potential of genetic algorithms (GA) via a variant of NSGA-II is explored to cope with the multi-objective formulation, in order to automatically produce the Pareto front. The model formulation has then been extended to take into account demand uncertainty, giving more robustness to the proposed approach. Two case studies support the analysis: first at regional level, the results of a HSC design for the former Midi-Pyrénées region obtained with both models are compared. The solutions obtained by GA exhibit the same order of magnitude as those obtained with MILP (Mixed Integer Linear Programming) in the mono-criterion problem, but better compromise solutions are produced in the multi-objective formulation and more flexible ones are obtained with demand uncertainty modelling. Then an airport ecosystem, i.e. Tarbes-Lourdes has been studied: the airport infrastructure is an interesting case study, since an airport is a source of emissions that affect climate, including the emissions generated from activities occurring inside and outside the airport perimeter fence associated with the operation and use of an airport. Finally, a post-optimal analysis on a compromise solution of HSC configuration is carried out based via two cost-benefit analyses (CBA) from a social (SCBA) and governmental perspective (subsidies and taxes). The SCBA approach for hydrogen deployment integrates societal benefits for the reduction of greenhouse gas emissions, noise air pollution abatement and social costs for the increase in platinum consumption in the manufacture of fuel cells. By including external costs, economic benefits of the replacement of ICEV (internal combustion engine) by FCV (Fuel Cell Vehicles) were highlighted as well as the generation of positive social net present values
34

THE EFFECTS OF JOB SEEKER PERCEPTIONS OF NETWORKING AND EXTRAVERSION ON NETWORKING BEHAVIOR

Menzies, Derek T. January 2021 (has links)
No description available.
35

The Effects of Urban Form on Vehicle Emissions - Focusing On Urban Form Factors and Three Conventional Air Pollutions and Carbon Dioxide -

Lee, Jae Choon 20 December 2012 (has links)
No description available.
36

Šest esejí o meta-regresní analýze / Six Essays on Meta-Regression Analysis

Havránková, Zuzana January 2015 (has links)
This dissertation thesis consists of six papers on macroeconomics, international economics, and energy economics. All the papers are tied together by the use of meta-regression analysis, which is essential for the derivation of robust policy-relevant conclusions from often conflicting results presented in the empirical literature. I use meta-analysis to quantitatively synthesize the reported research results on a given topic, correct the literature for publication selection bias, and filter out the effect of various misspecifications present in some primary studies. My results can be summarized as follows: 1) The elasticity of intertemporal substitution in consumption, a key input to all dynamic models in finance and macroeconomics, varies significantly across countries. The differences can be explained by the level of stock market participation, when countries with higher participation exhibit larger values of the elasticity; the mean reported elasticity is 0.5. 2) The effect of borders on international trade, which most authors find to be surprisingly large, can be explained away by innovations in methodology introduced in the last decade. When these innovations are taken into account jointly, the border effect disappears for developed countries, and is relatively small for developing countries. 3) When...
37

Carbon Lock-in and Decarbonization Pathways at the University of Dayton

Worsham, Matthew 24 May 2017 (has links)
No description available.
38

Comparative analysis of the optimization, size, economic feasibility, and carbon emissions for fixed and single-axis tracking solar photovoltaic arrays that meet the total electric power needs of Miami University

Soules, Travis P. 01 August 2017 (has links)
No description available.

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