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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.
201

A multi-disciplinary conceptual design methodology for assessing control authority on a hybrid wing body configuration

Garmendia, Daniel Charles 07 January 2016 (has links)
The primary research objective was to develop a methodology to support conceptual design of the Hybrid Wing Body (HWB) configuration. The absence of a horizontal tail imposes new stability and control requirements on the planform, and therefore requiring greater emphasis on control authority assessment than is typical for conceptual design. This required investigations into three primary areas of research. The first was to develop a method for designing an appropriate amount of redundancy. This was motivated widely varying numbers of trailing edge elevons in the HWB literature, and inadequate explanations for these early design decisions. The method identifies stakeholders, metrics of interest, and synthesizes these metrics using the Breguet range equation for system level comparison of control surface layouts. The second area of research was the development trim analysis methods that could accommodate redundant control surfaces, for which conventional methods performed poorly. A new measure of control authority was developed for vehicles with redundant controls. This is accomplished using concepts from the control allocation literature such as the attainable moment subset and the direct allocation method. The result is a continuous measure of remaining control authority suitable for use during HWB sizing and optimization. The final research area integrated performance and control authority to create a HWB sizing environment, and investigations into how to use it for design space exploration and vehicle optimization complete the methodology. The Monte Carlo Simulation method is used to map the design space, identify good designs for optimization, and to develop design heuristics. Finally, HWB optimization experiments were performed to discover best practices for conceptual design.
202

World oil supply and unconventional resources : Bottom-up perspectives on tight oil production

Wachtmeister, Henrik January 2018 (has links)
Oil is the world’s largest primary energy source. It dominates the transportation sector which underpins the world economy. Yet, oil is a nonrenewable resource, destined not to last forever. In the mid-2000s global conventional oil production stagnated, leading to rising oil prices and fears of permanent oil scarcity. These fears, together with the high prices, receded with the unforeseen emergence of a new supply source: tight oil. This licentiate thesis investigates unconventional tight oil production and its impacts on world oil supply in terms of resource availability and oil market dynamics, and in turn briefly discusses some possible wider economic, political and environmental implications of these impacts. The thesis is based on three papers. The first investigates the usefulness of bottom-up modelling by a retrospective study of past oil projections. The second looks at how unconventional tight oil production can be modelled on the well level using decline curve analysis. The third derives typical production parameters for conventional offshore oil fields, a growing segment of conventional production and a useful comparison to tight oil. The results show that tight oil production has increased resource availability significantly, as well as introduced a fast responding marginal supply source operating on market principles rather than political ones. The emergence of tight oil production has altered OPEC’s strategic options and led to a period of lower and less volatile oil prices. However, this condition of world oil supply can only last as long as the unconventional resource base allows, and, at the same time, total fossil fuel consumption will have to fall to limit climate change. It is concluded that this breathing space with lower oil prices could be used as an opportunity to develop and implement policy for an efficient managed decline of global oil use in order to achieve the dual goals of increased human economic welfare and limited climate change, and in the process preempt any future oil supply shortage. Unconventional tight oil production can both help and hinder in this endeavor. Accurate models and analyses of oil production dynamics and impacts are therefore crucial when maneuvering towards this preferred future.
203

Le rôle des gaz conventionnels et non-conventionnels dans la transition énergétique en Asie / The role of conventional and unconventional gas in the energy transition in Asia

Le, Minh Thong 05 September 2017 (has links)
Les problématiques de l’énergie et de l’environnement sont un des principaux défis pour l’humanité au XXIème siècle. La croissance mondiale de la demande d’énergie est confrontée aux préoccupations environnementales (y compris la pollution, le réchauffement climatique et la réduction des émissions de CO2), en particulier dans les régions en croissance économique rapide comme l’Asie. Le transfert de l’utilisation des sources d’énergies traditionnelles comme le charbon, le pétrole, vers les sources d’énergie plus propres et des énergies renouvelables est une tendance inévitable à l’avenir. Dans le contexte actuel, le gaz naturel est considéré comme une source d’énergie propre qui jouera un rôle important dans le processus de transition énergétique vers une économie bas-carbone. Les conséquences pour les marchés de gaz naturel peuvent être considérables. La condition d’une telle évolution est de disposer d’une offre en gaz naturel importante. Le développement du gaz non conventionnel, en particulier le gaz de schiste, fournit une opportunité d’expansion de l’approvisionnement gazier mondial comme le montre la « révolution du gaz de schiste » aux États- Unis. Celle-ci a profondément modifié les marchés gaziers régionaux. Toutefois, cette « révolution » n’est guère reproductible à d’autres régions du monde. Cette thèse démontre en particulier qu’en dehors des facteurs géologiques, des conditions institutionnelles (fiscalité, droits de propriété), économiques (prix, technologies) et organisationnelles (libéralisation des marchés) sont nécessaires pour assurer un développement à grande échelle des ressources non conventionnelles. Cette thèse montre que ces conditions ne sont pour la plupart pas réunies ni en Europe ni en Asie (notamment en Chine). Dès lors, une transition par le gaz pour répondre aux enjeux climatiques en Asie se fera par la voie des importations et non par une production propre à la région. A partir de trois scénarios du modèle POLES basés sur des hypothèses de politique climatique, de développement du gaz de schiste et d’augmentation rapide de la demande de gaz dans le mix énergétique, en particulier en Asie, deux principales conclusions émergent. Tout d’abord, l’importance du développement des gaz de schistes aux USA, leur bas coût de production induisent au niveau mondial une offre de gaz abondante et compétitive par rapport à d’autres énergies notamment par rapport au charbon. Par conséquent, même sans politique climatique, les conditions sont réunies pour que la part du gaz naturel puisse croître dans le mix énergétique. Deuxièmement, une politique climatique affirmée a des effets contradictoires quant à l’importance du gaz naturel dans les mix énergétiques des pays asiatiques. D’un côté elle permet une pénétration plus importante du gaz naturel dans leur mix énergétique. Mais dans le même temps, limitant la demande d’énergie, les volumes de gaz naturel demandés ne sont que légèrement plus importants que dans des scénarios sans politique climatique. / Energy and environmental issues are one of the main challenges for humanity in the 21st century. Global growth in energy demand links to environmental concerns including pollution, global warming and reduction of CO2 emissions. In particular, it is an urgent request in rapidly growing developing regions such as Asian countries. Using cleaner energy sources, renewable energy instead of traditional energy sources like coal and oil is an inevitable option in the future. In the current context, natural gas is seen as a clean energy source which plays a major role in the energy transition process towards a low-carbon economy. The consequences for natural gas markets are significant and the condition of this change is an abundant supply of natural gas. The development of unconventional gas, particularly shale gas, provides an opportunity to expand the global gas supply. This is illustrated by the “shale gas revolution” in US which has profoundly changed the regional gas markets. However, this "revolution" is hardly reproducible in other regions of the world. This thesis demonstrates particularly that apart from geological, institutional conditions (taxation, property rights), economic (prices, technologies) and organizational (free markets) are necessary for a large scale development of unconventional resources. This research also shows that most of these conditions are not met in Europe or Asia (especially in China). Therefore, an energy transition by natural gas to meet climate challenges in Asia will be solved through imports, rather than through regional production. From three scenarios of the POLES model based on assumptions about climate policy, shale gas development and rapid increase of demand for gas in the energy mix (particularly in Asia), two main conclusions emerge. The developments of shale gas with low cost in the USA make the global gas supply abundant and more competitive than other energies, particularly coal. Therefore, even without climate policy, the conditions are ripe for the increaseof natural gas proportion in the energy mix. Secondly, a strong climate policy has contradictory effects on the relative share of natural gas in the Asian energy mix. On the one hand, it allows natural gas larger penetration into the energy mix of Asia. But at the same time, with limitation of energy demand, requested natural gas volumes are only slightly higher than in scenarios without climate policy.
204

An analysis of monetary policy transmission through bond yields

Lloyd, Simon Phillip January 2017 (has links)
In this thesis, I study the transmission of monetary policy through the term structure of interest rates. This is an important topic because, with short-term nominal interest rates in many advanced economies close to their effective lower bound since 2008-2009, central banks have used `unconventional' monetary policies, such as large-scale asset purchases and forward guidance, to stimulate macroeconomic activity by, inter alia, placing downward pressure on longer-term interest rates. I focus on the mechanisms through which monetary policy influences bond yields, domestically and globally, with reference to a canonical decomposition of longer-term interest rates into expectations of future short-term interest rates, and term premia. After an introduction in chapter 1, chapter 2 appraises the use of overnight indexed swap (OIS) rates as measures of expected future monetary policy. Unlike federal funds futures (FFFs), which have regularly been used to construct measures of US interest rate expectations, OIS rates are available in many countries. I find that US OIS rates provide measures of interest rate expectations that are as good as those from FFFs, and that US, UK, Eurozone and Japanese OIS rates up to a 2-year horizon tend to accurately measure interest rate expectations, providing comparable cross-country measures of monetary policy expectations. In chapter 3, I propose a novel method for estimating interest rate expectations and term premia at short and long-term horizons: a no-arbitrage Gaussian affine dynamic term structure model (GADTSM) augmented with OIS rates. Using 3 to 24-month OIS rates, the OIS-augmented model generates estimates of the expected path of short-term interest rates out to a 10-year horizon that closely correspond to those implied by FFFs rates and survey expectations, outperforming existing GADTSMs. I study the transmission of US unconventional monetary policies in chapter 4. Using the OIS-augmented GADTSM, I carry out an event study to demonstrate that US unconventional monetary policy announcements between November 2008 and April 2013 did significantly reduce US longer-term interest rates by affecting expectations and term premia. As a result of these declines, unconventional monetary policies aided US real economic outcomes. Using a structural vector autoregression, I show that changes in interest rate expectations, linked to monetary policy signalling, had more expansionary effects on US real economic outcomes than changes in term premia, associated with portfolio rebalancing. Chapter 5 assesses the international transmission of monetary policy through the term structure of interest rates between advanced economies. I present a micro-founded, two-country model with endogenous portfolio choice amongst country-specific short and long-term bonds, and equity. Within the model, US monetary policy has sizeable effects on longer-term interest rates in other advanced economies, which are similar to empirical estimates. Using the OIS-augmented GADTSM in an event study, I show that US monetary policy has led to changes in interest rate expectations in other advanced economies that amplify global spillovers, which have been partly mitigated by changes in term premia through portfolio rebalancing.
205

Strategic Negligence: Why the United States Failed to Provide Military Support to the Syrian Resistance in 2011-2014

Trautman, Konrad J. 28 March 2018 (has links)
The US military’s culture, structure, and process for providing advice to the president and his national security decision-making team are flawed due to the marginalization of unconventional warfare (UW) expertise -- UW is the military’s doctrinal term for support to resistance activities and movements. This marginalization results in inadequate consideration for applying UW as a strategic option for the nation. Through a qualitative methods case study analysis utilizing macro- and micro-level process-tracing with a conceptual framework based on Niklas Luhmann’s Systems Theory, the author shows that viable and acceptable resistance elements existed in Syria in March 2011 to June 2014 and that the conventional US military failed to recognize this development, adequately analyze its implications, and craft a strategic UW option for the national security decision-makers to consider. This finding is significant in that it exposes a deficiency in the US military’s culture, structure and process that results in an incomplete and insufficient menu of military options for the president. If these cultural, structural, and procedural flaws are left unaddressed, the US is likely to repeat this strategic error in the future. The author identifies specific recommendations for national security practitioners; however, the overarching theme is the need to change the institutional culture and the old structures of the conventional military to be able to provide the president a more complete, comprehensive, and creative menu of options to consider when assessing and responding to violent political crises short of conventional war.
206

On the distributive impact of unconventional monetary policy

Lima, Daniel Albuquerque Maranhão de 05 May 2016 (has links)
Submitted by Daniel Albuquerque Maranhão de Lima (daniel.maranhao.lima@gmail.com) on 2016-06-01T02:19:51Z No. of bitstreams: 1 output.pdf: 429570 bytes, checksum: 0fe975444d41f0be6bc01f2cb18d4a2d (MD5) / Rejected by Letícia Monteiro de Souza (leticia.dsouza@fgv.br), reason: Prezado Daniel, Favor alterar seu trabalho de acordo com as normas ABNT: 1 - cabeçalho da capa: O nome da fundação e também da escola devem constar. Favor verificar trabalho de seus outros amigos para comparação. Atenciosamente, Letícia Monteiro 3799-3631 on 2016-06-01T12:09:37Z (GMT) / Submitted by Daniel Albuquerque Maranhão de Lima (daniel.maranhao.lima@gmail.com) on 2016-06-02T02:11:45Z No. of bitstreams: 1 output.pdf: 429714 bytes, checksum: a733d2b7e509a82de2f56129c3f6527e (MD5) / Rejected by Suzinei Teles Garcia Garcia (suzinei.garcia@fgv.br), reason: Bom dia Daniel, Faltou a página de AGRADECIMENTOS após a folha de assinaturas - deve agradecer pelo menos seu orientador. Na capa e contra capa descer um pouco seu nome deixa mais no meio da página. Grata. Suzi 3799-7876 on 2016-06-02T11:59:26Z (GMT) / Submitted by Daniel Albuquerque Maranhão de Lima (daniel.maranhao.lima@gmail.com) on 2016-06-03T01:24:49Z No. of bitstreams: 1 diss.pdf: 430517 bytes, checksum: a8e7f210288cce77003117755a089a5b (MD5) / Rejected by Letícia Monteiro de Souza (leticia.dsouza@fgv.br), reason: Prezado Daniel, Favor alterar seu trabalho de acordo com as normas ABNT: 1- como os agradecimentos são em português, o título também deverá ser. Caso queira deixar o em inglês, favor deixar o texto na língua respectiva. Atenciosamente, Letícia Monteiro 3799-3631 on 2016-06-03T12:23:46Z (GMT) / Submitted by Daniel Albuquerque Maranhão de Lima (daniel.maranhao.lima@gmail.com) on 2016-06-03T12:29:32Z No. of bitstreams: 1 dissertação.pdf: 430340 bytes, checksum: de324c6aaec40365c016a31d8593c460 (MD5) / Approved for entry into archive by Letícia Monteiro de Souza (leticia.dsouza@fgv.br) on 2016-06-03T12:33:10Z (GMT) No. of bitstreams: 1 dissertação.pdf: 430340 bytes, checksum: de324c6aaec40365c016a31d8593c460 (MD5) / Made available in DSpace on 2016-06-03T12:37:54Z (GMT). No. of bitstreams: 1 dissertação.pdf: 430340 bytes, checksum: de324c6aaec40365c016a31d8593c460 (MD5) Previous issue date: 2016-05-05 / Logo após à crise financeira de 2007-08 o Federal Reserve interveio para tentar controlar a recessão. No entanto, ele não apenas baixou os juros, como também adotou políticas não-convencionais, incluindo o empréstimo direto para empresas em mercados de crédito de alto nível. Estas novas medidas foram controversas e alguns opositores protestaram porque elas estariam ajudando disproporcionalmente aquelas pessoas ligadas ao sistema financeiro que já eram ricas. Nós utilizamos um modelo DSGE para a análise de políticas monetária não convencional e introduzimos dois tipos distintos de agentes, capitalistas e trabalhadores, para investigar o seu impacto distributivo. Nós encontramos que a política de crédito to Fed foi bem sucedida no mercado de trabalho, o que ajuda mais os trabalhadores, e introduziu um novo competidor no mercado bancário, o governo, o que prejudica mais os capitalistas. Logo, nós encontramos que a política de crédito diminuiu a desigualdade nos EUA. / In the aftermath of the 2007-08 financial crisis the Federal Reserve intervened to help fight the recession. However, it not only lowered interest rates, but also put in practice unconventional measures, including direct lending to companies in high-grade credit markets. These new measures were controversial and some opponents protested it for helping disproportionately the already wealthy individuals tied to the financial sector. We build on a conventional DSGE model for unconventional monetary policy evaluation and introduce two distinct types of agents, capitalists and workers, to assess its distributive impact. We find that the credit policy by the Fed was effective in labor markets, which helps relatively more workers, and introduced a new competitor to banks, the government, which hurts capitalists more. Thus, we find that the credit policy lowered inequality in the US.
207

Electrical transport properties of URhGe and BiPd at very low temperature

Barraclough, Jack Matthew January 2015 (has links)
URhGe has garnered interest recently as one of the few known ferromagnetic superconductors. The superconductivity in this material appears to arise from magnetic fluctuations rather than phonons, and take a triplet form which is remarkably resistant to field. In this thesis, a number of measurements on the material are presented. Some probe the Fermiology, with strong evidence appearing for a model which as both light open sheets and heavy, small, closed pockets. The open sheets, associated with chains of real-space electron density running along the b axis, dominate the conductivity in most circumstances. Evidence for their existence arises from the general large and non-saturating magnetoresistance, and from the unusual observation of negative temperature coefficient of resistance at high fields. The closed pockets have provided a few Shubnikov-de Haas oscillations, but mostly they remain inferred from the high specific heat γ and their role in the magnetism. In order to better probe the superconductivity, a high precision low noise DC resistance measurement bridge was built using a SQUID. Along with conventional measurements, this provides evidence that the two pockets of superconductivity on the phase diagram are the same phase. The re-entrance an be understood simply as a result of magnetic field being a tuning parameter, but also suppressing bulk superconductivity through orbital limiting. The SQUID bridge allowed the detection of domain wall superconductivity linking up these two pockets. The SQUID bridge was also used to study the highly structured superconducting transition in BiPd. This material lacks inversion symmetry in its crystal structure, so is a good candidate for unusual forms of superconductivity. Here again non-bulk superconductivity is considered the most likely cause for the structure. Unusual and distinctive IV curves have been measured, and a simple model of inhomogeneous conductivity channels with different critical currents is proposed as an explanation.
208

Avaliação do potencial gerador da formação Tremembé, bacia de Taubaté, área de Pindamonhangaba e Moreira César-SP / Evaluation of the generation potential of the Tremembé formation, Pindamonhangaba - Moreira César area

Fernanda Setta Duarte 16 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo aborda a caracterização faciológica e quimioestratigráfica do intervalo de folhelhos betuminosos da Formação Tremembé (Oligoceno da Bacia de Taubaté), bem como a avaliação econômica desses depósitos na região de Pindamonhangaba e Moreira César, SP. A partir da coleta sistemática de amostras de testemunhos do poço MOR-SP, foram determinados os teores de COT, S e RI, assim como dados de Pirólise Rock-Eval. Com base nesses dados seis unidades quimioestratigráficas(designadas de I a VI a partir da base) foram definidas no intervalo de cerca de 40 metros de espessura. Dados previamente estudados dos poços TMB-SP e PND-SP foram utilizados para correlação dessasunidades.Com base nos dados de Pirólise RockEval foi possível quantificar o volume de óleo potencialmente recuperável através do aproveitamento industrial dos folhelhos betuminosos. No intervalo mais promissor (unidades VI e V), compreendendo uma seção de cerca de 17 metros de espessura, o rendimento de óleo é de cerca de 25,7 milhões de barris por km2, na área do poço MOR-SP.Os dados obtidos apontam para uma importante jazida não convencional de folhelho betuminoso (oilshale), cujo aproveitamentoeconômico, se executado,requerirá, além de novas soluções tecnológicas, a implementação de ações de forma a minimizar os impactos sociais e ambientais de uma possível operação extrativa desse recurso. / The present study deals with the faciologic and chemostratigraphic characterization of the oil shale interval of the TremembéFormation(Oligocene, TaubatéBasin), and the economic evaluation of these deposits in the Pindamonhangaba and Moreira Cesar,SP regions. From the systematic sampling of the MOR-SP borehole, we determined TOC, S and IR contents, as well as data from Rock-Eval pyrolysis. Based on these data, six chemostratigraphic units (designated from I up to VI in the base) were defined in the interval of about 40 meters in thickness. Data previously studied of TMB-SP and PND-SP wells were used for correlation of these units. Based on data from Rock-Eval pyrolysis, it was possible to quantify the volume of oil potentially recoverable through industrial exploitation of bituminous shale. In the most promising interval (units V and VI), comprising a section of about 17 meters thick, the oil yield is about 25.7 million barrels perkm2 in the area of MOR-SP well. The data point is an important deposit of non-conventional bituminous shale (oilshale), which sees an economic use, if implemented, will require additional new technological solutions, the implementation of actions to minimize the social and environmental impacts of a possible extractive operation of this resource.
209

Zeeman effects in heavy electron superconductors / Effets Zeeman dans les supraconducteurs à électrons lourds

Michal, Vincent P. 31 October 2012 (has links)
Comprendre les propriétés des composés à électrons fortement corrélés nouvellement découverts est un important défi à la fois pour des raisons fondamentales et un impact industriel à long terme. Une activité expérimentale sur les métaux et supraconducteurs à électrons lourds a mis en évidence des effets qui se démarquent clairement de notre compréhension actuelle. Le but de cette thèse est de modéliser les effets de spin spéciaux qui ont été observés en réponse à un champ magnétique dans le supraconducteur CeCoIn(5). Elle est composée de deux parties. Dans un premier temps nous avons à faire à la distribution anormale du champ magnétique local dans le réseau de vortex révélé par les expériences de diffraction de neutrons à petits angles et rotation de spin muonique. Sur la base de a théorie de Ginzburg-Landau avec prise en compte de l'effet de spin, nous analysons l'inhomogénéité du champ local dans le réseau de vortex et calculons des expressions pour les facteurs de forme en diffraction neutronique et la largeur de raie statique en rotation de spin muonique. Nous montrons que les données expérimentales anormales sont le résultat de supercourants générés par le spin circulant autour du cœur du vortex et donnent une augmentation de l'inhomogénéité du champ sur une distance de l'ordre de la longueur de corrélation du supraconducteur à partir de l'axe du vortex. L'importance de l'effet est contrôlée par une seule quantité (le paramètre de Maki) qui permet la détermination de propriétés physiques du système à partir de données expérimentales. La seconde partie traite d'une transition d'onde de densité de spin presque commensurable dans un supraconducteur non-conventionnel. Elle est motivée par l'observation du confinement d'un ordre d'onde de densité de spin dans la phase supraconductrice de CeCoIn(5) dans un champ magnétique. Dans le cadre de la formulation spin-fermion nous proposons un mécanisme pour la transition de l'état fondamental qui consiste du ralentissement du mode collectif de fluctuation de densité de spin induit par le champ (exciton de spin) vers un ordre statique. Cela représente un scénario par lequel la transition vers l'ordre de spin est reliée intrinsèquement au supraconducteur. / Understanding the properties of newly discovered strongly correlated electron compounds is a considerable challenge for both fundamental matters and long-term industrial impact. Experimental activity on heavy electron metals and superconductors has lead to highlighting effects that depart from current knowledge. The thesis is aimed at modelling effects that have been observed in response to magnetic field in the heavy electron superconductor CeCoIn$_5$. This consists of two parts. In the first time we deal with the vortex lattice state anomalous local magnetic field space variations as highlighted by small angle neutron scattering and muon spin rotation experiment. On the basis of the Ginzburg-Landau theory with account of spin effect, we analyse the local field inhomogeneity in the vortex lattice and derive expressions for the neutron scattering form factors and muon spin rotation static linewidth. The anomalous experimental data are shown to be result of spin driven supercurrents which circulate around the vortex cores and lead to an increase with external field in the internal field inhomogeneity on a distance of the order of the superconducting coherence length from the vortex axis. The importance of the effect is controlled by a single quantity (the Maki parameter). The second part is on nearly commensurate spin density wave transition in a quasi two-dimensional superconductor. It is motivated by observation of the confinement of spin density wave ordering inside the superconducting state of CeCoIn$_5$ in magnetic field. In the frame of the spin-fermion formulation we propose a mechanism for the ground state transition consisting in the field-induced slowing down of a collective spin density fluctuation mode (spin-exciton) to static ordering. This represents a scenario by which the transition to spin ordering is intrinsically related to superconductivity
210

Custos de manutenção em HIS construídas com o sistema inovador de parede de placas moldadas in loco: um estudo de casos no conjunto Mariz I em João Pessoa-PB

Silva, Maisa Beatriz Marinho Fausto da 31 March 2016 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2017-07-20T13:50:17Z No. of bitstreams: 1 arquivototal.pdf: 3151113 bytes, checksum: 11e87c35ec2899531a26a1da6a8d7bd0 (MD5) / Made available in DSpace on 2017-07-20T13:50:18Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3151113 bytes, checksum: 11e87c35ec2899531a26a1da6a8d7bd0 (MD5) Previous issue date: 2016-03-31 / Financiadora de Estudos e Projetos - Finep / The buildings are degraded over time, requiring therefore performing maintenance services. These services generate costs, which are the maintenance costs. And when you speak of the study of maintenance costs in Social Housing, this is a little explored subject, and when it comes to the ones which were built with some innovative/ unconventional building system even more. From the knowledge of this gap in terms of maintenance costs on Social Housing and starting from this scenario this dissertation addresses the issue of maintenance costs in Social Housing that used the innovative building system of "sealing walls in molded concrete slabs on site" from the district Mariz I, located in João Pessoa-PB. For the elaboration of the aforementioned dissertation the approach method was deductive, we used the techniques of direct and indirect documentation (extensive) and was adopted probabilistic sampling process. The research that was carried out and has as product this dissertation is classified as to nature, in quantitative, as the purpose in applied, as the type, descriptive and on the design, in survey research. This work proposes to detail all the items that have undergone maintenance over the years studied in the Social Housing addressed, as well as costs arising from this activity, called actual costs; seeking in prior, with the known values of maintenance expenditures, to project itself in terms of future costs for a given period in each case, from the development of a measurement tool for the maintenance costs that uses the principle of cost-significant item (CSI) and aided by statistical mechanisms. However, as the work progressed other relevant factors were becoming notorious, such as the influence of socioeconomic status of the buildings residents with maintenance costs; the calculation of the cost items that were not done maintenance work, but it was found the need to be made, those called potential costs; the perception of the buildings conservation status in the optics of quality of maintenance practice, among others. In general it was found that the maintenance of the activity was carried out informally and in corrective manner. It has been seen that 22% of maintenance items contributed to 95% of the actual costs of the analyzed buildings. The paint item was the most representative, in terms of effective maintenance costs. About the potential costs, in the most of dwellings, there was a tendency of proportional reversal of the amount thereof compared to actual costs. The values of the maintenance costs were directly proportional to the purchasing power of residents, income limitations of these influenced the absence / postponement of the building’s maintenance, and also in the final result of their execution. / As edificações sofrem degradação com o tempo, necessitando, portanto, da realização de serviços de manutenção. Esses serviços geram despesas, que são os custos de manutenção. E quando se fale do estudo dos custos de manutenção em HIS, este é um assunto pouco explorado, e se tratando das que foram construídas com algum sistema construtivo inovador/não convencional ainda mais. A partir do conhecimento desta lacuna em termos de custos de manutenção em HIS e partindo desse panorama a presente dissertação aborda a questão dos custos de manutenção em HIS que utilizaram o sistema construtivo inovador de “paredes de vedação em placas de concreto moldadas in loco” do conjunto Mariz I, localizado na cidade de João Pessoa- PB. Para a construção da supracitada dissertação o método de abordagem utilizado foi o dedutivo, foram utilizadas as técnicas de documentação indireta e direta (extensiva) e foi adotado o processo de amostragem probabilista. A pesquisa que foi realizada e tem como produto esta dissertação, classifica-se quanto à natureza, em quantitativa, quanto à finalidade em aplicada, quanto ao tipo em descritiva e quanto ao delineamento, em pesquisa de levantamento. Este trabalho se propôs a detalhar todos os itens que sofreram manutenção ao longo dos anos estudados nas HIS abordadas, bem como os custos oriundos desta atividade, denominados de custos efetivos; buscando a priori com os valores conhecidos dos gastos com manutenção se projetar apenas em termos de custos futuros para um dado período em cada caso específico, a partir do desenvolvimento de uma ferramenta de mensuração de custo de manutenção que utiliza-se do princípio de itens custos significativos (CSI) e auxiliada por mecanismos estatísticos. No entanto, à medida que se deu o andamento do trabalho outros fatores relevantes foram se tornando notórios, tais como: a influência da situação socioeconômica dos moradores das edificações com os custos de manutenção; o cálculo dos custos de itens em que não foram feitas intervenções de manutenção, mas que se constatou a necessidade de serem feitas, estes denominados de custos potenciais; a percepção do estado de conservação das edificações na ótica da qualidade da prática da manutenção, entre outros aspectos. Em linhas gerais constatou-se que a atividade de manutenção, foi realizada informalmente e de maneira corretiva. Foi visto que 22% dos itens de manutenção contribuíram com 95% dos custos efetivos das edificações analisadas. O item pintura foi o mais representativo, em termos de custos efetivos de manutenção. Sobre os custos potenciais, na maioria das moradias, há uma tendência de inversão proporcional do montante destes, em relação aos custos efetivos. Os valores dos custos de manutenção foram diretamente proporcionais ao poder aquisitivo dos moradores, as limitações de renda destes influenciaram na ausência/protelação da manutenção das edificações, mas também no resultado final da sua execução.

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