Com a reestruturação do modelo do setor elétrico brasileiro, a partir do Projeto RE-SEB, as empresas de distribuição de energia elétrica no Brasil tiveram que se adequar às novas regras de mercado, bem como alterar a sua maneira de administrar a empresa. Com o conceito de regulação por incentivos e competição por mercado, e não competição no mercado, novos mecanismos de mitigação de riscos de mercado foram introduzidos no modelo do setor elétrico, de tal forma que as empresas de distribuição de energia elétrica sejam ressarcidas de maneira justa pelo serviço prestado à sociedade. Diante desse contexto, a gestão eficiente da empresa e, conseqüentemente, o fato de atingir as metas de desempenho pré-estabelecidas pela alta administração de cada distribuidora depende cada vez mais do conhecimento das regras de mercado por seus colaboradores, bem como da utilização dos mecanismos de mitigação de riscos de mercado das distribuidoras. Assim, esse trabalho pretende analisar os principais mecanismos de mitigação de riscos de mercado das distribuidoras envolvidos no processo de repasse dos custos de aquisição de energia elétrica às tarifas dos consumidores finais, bem como avaliar os dispositivos previstos na regulamentação legal, inserindo um estudo de caso que analisa o portfólio de contratação de uma empresa de distribuição de energia elétrica fictícia, simulando variações nos níveis de contratação da mesma bem como no portfólio, avaliando a utilização dos mecanismos de mitigação de riscos de mercado e as alternativas simuladas, como também identificando os pontos de sucesso e os pontos a serem melhorados na gestão e contratação da distribuidora. / As the restructuring of the model of the Brazilian electric sector, with the Project RE-SEB, the electric energy distribution companies in Brazil had to adjust themselves to the new rules of the market, as well as modify their way of manage the company. As the concept of regulation for incentives (price cap model) and competition by market, and not competition in the market, new mechanisms to reduce the risks of the market had been introduced in the model of the electric sector, in such a way that the electric energy distribution companies receive a fair revenue for the service delivered to the society. In this perspective, the efficient management of the company and, consequently, the fact of reaching the goals in the performance targets established by the high administration, depends on the deep knowledge of the rules of market by its technical team , as well as the use of the mechanisms to reduce the risks of the market of the distribution utilities. In this way, this work intends to analyze (i) the main mechanisms available to the distribution companies in order to mitigate the market risks in the process of contract energy supply and to pass-though such costs to the final consumers, as well as (ii) evaluate the rules implemented in the legal regulation framework. Furthermore, to illustrate the analysis, a case study was developed focusing the contract portfolio of a fictitious distribution company, simulating variations in the contracted energy volume as well as in the portfolio composition, evaluating the uses of the mitigation mechanisms of the market risks and solution alternatives to minimize such risks, searching for improvements that could be made in the management strategy of energy supply contracting.

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-08-16T14:16:06Z No. of bitstreams: 1 Rafael Villar Gagliardi.pdf: 2777437 bytes, checksum: be08f53406a3948725d12365d9b38890 (MD5) / Made available in DSpace on 2016-08-16T14:16:06Z (GMT). No. of bitstreams: 1 Rafael Villar Gagliardi.pdf: 2777437 bytes, checksum: be08f53406a3948725d12365d9b38890 (MD5) Previous issue date: 2016-04-01 / The purpose of this work is to investigate whether the conduct of one of the parties, referred to as creditor, once the counterparty, referred to as debtor, has committed a contractual breach, is in anyway relevant for the purposes of defining the indemnification to be ultimately awarded to the former or if, on the contrary, such conduct is absolutely irrelevant to the mentioned purpose. It aims to identify if Brazilian Law encompasses the notion according to which it is expected from the creditor to act reasonably to mitigate the losses flowing from the breach attributable to the debtor. The starting point of the investigation lies in the finding of transformations in Private Law, especially in the field of civil liability, in the restatement of the values that constitute the axiological chart that must inspire the exercise of rights, prerogatives or legal positions and the growing role played by the principles of solidarity, sociality, ethicalness, activity, goodfaith and the social function of contracts. From there, a solid foundation is built on which a theory of mitigation of damages may rest, making it possible to find the justification and the legal grounds that allow the insertion of the rule of mitigation into Brazilian Law. Once the justification and the legal grounds are identified, the legal requirements for the rule of mitigation of loss to apply are analyzed, as well as the effects resulting from the conducts of the creditor who fails to mitigate the losses flowing from the breach of contract, the one who does act to mitigate the loss, and in this case, both the situations where mitigation is successful and the situations where it is not. The treatment to be given to expenses borne by the creditor when acting to mitigate the loss flowing from the breach is also covered, as well as the parties ability to deal with mitigation in contracts and the procedural aspects of the matter, namely allocation of the burden of proof and the (im)possibility of the adjudicator ruling on the matter without it being properly raised / Este trabalho tem como objetivo investigar se o comportamento de uma parte, assim designada credor, a partir da ocorrência de um inadimplemento contratual imputável à contraparte, assim designada devedor, possui alguma importância para a conformação final da indenização a ser concedida em favor do primeiro ou se, ao contrário, esse comportamento seria irrelevante para tal finalidade. Busca-se identificar se o Direito Brasileiro acolhe a noção segundo a qual se espera do credor que atue razoavelmente para mitigar os danos decorrentes do inadimplemento imputável ao devedor. A investigação parte da constatação de transformações sofridas pelo Direito Privado, em especial no âmbito da responsabilidade civil, da renovação dos valores que constituem a pauta axiológica que deve inspirar o exercício de direitos, faculdades, prerrogativas ou posições jurídicas e do crescente papel desempenhado pelos princípios da solidariedade, da socialidade, da eticidade, da atividade, da boa-fé objetiva e da função social do contrato. A partir daí, constrói-se uma base sólida sobre a qual uma teoria da mitigação de danos possa se apoiar, identificando-se a justificativa e o fundamento pela qual a mitigação de danos passa a integrar o ordenamento brasileiro. Encontrados a justificativa teórica e o fundamento buscados, são analisados os requisitos para incidência da regra de mitigação de danos, bem como os efeitos atribuídos às condutas do credor que não age para mitigar os danos decorrentes do inadimplemento da contraparte, quanto daquele que o faz, inclusive quando realizada sem sucesso a mitigação. Analisa-se, também, o tratamento a ser dispensado às despesas suportadas pelo credor nessa atuação, bem como a possibilidade de as partes disporem contratualmente sobre a mitigação de danos, além dos aspectos processuais aplicáveis, que incluem a distribuição do ônus da prova e a (im)possibilidade de conhecimento da matéria de ofício pelo julgador

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2016-11-09T10:49:17Z No. of bitstreams: 1 Mariana Marques Calfat.pdf: 1015342 bytes, checksum: e6813079af0a5619862081215ae600dd (MD5) / Made available in DSpace on 2016-11-09T10:49:17Z (GMT). No. of bitstreams: 1 Mariana Marques Calfat.pdf: 1015342 bytes, checksum: e6813079af0a5619862081215ae600dd (MD5) Previous issue date: 2016-09-13 / The paper is a study of the doctrine of avoidable damages under the light of the Brazilian law, which, unlike other systems, does not expressly predict the existence of the burden of mitigation. It tries to insert the concept of the duty to mitigate losses in this specific context, pointing out the main features of its institution, foundations, structure and growth prospects. Synthetically, this dissertation is divided into six chapters. The first chapter, theoretical framework, consists of opening remarks on the standards surrounding mitigation. The second chapter highlights international initiatives. The third and fourth chapters deal with the implementation of duty to mitigate losses in the Brazilian civil law. The fifth chapter develops the question of assessing the reasonableness of mitigation measures. The sixth chapter moves away from the individual-patrimonial approach and proposes the inclusion of the burden of mitigation as a guideline for governing the use of social wealth, going to the economic repercussions arising from the institution of the concept. Throughout this study, it is sought to demonstrate that the law imposes a specific conduct in order to mitigate losses resulting from default, given that the institutionalization of the concept would bring greater security to the parties involved, including judges. Finally, using the method of economic analysis of the law, it was found that the rule of mitigation could be used as a guideline governing the use of social wealth, fostering cooperation that should exist between individuals in order to avoid waste of relevant economic and social resources / O trabalho consiste no estudo da doutrina dos danos evitáveis à luz do Direito brasileiro que, diferente de outros ordenamentos, não previu expressamente a existência do ônus da mitigação. Buscou-se inserir o duty to mitigate the loss em contexto próprio, assinalando as principais características do instituto, seus fundamentos, estrutura e perspectivas de expansão. Sinteticamente, esta dissertação está dividida em seis capítulos. O primeiro capítulo, referencial teórico, faz considerações iniciais sobre a norma da mitigação. O segundo capítulo destaca as iniciativas internacionais. O terceiro e quarto capítulos tratam da aplicação da norma da mitigação no direito civil brasileiro. No quinto capítulo desenvolve-se a questão da aferição da razoabilidade das medidas mitigadoras. O sexto capítulo afasta-se do enfoque individual-patrimonialista da regra e propõe a inserção do ônus da mitigação enquanto norma orientadora que disciplina o usar da riqueza social, passando-se às repercussões econômicas oriundas do instituto. Através do presente trabalho, buscou-se demonstrar que o direito impõe uma conduta no sentido de se mitigar os prejuízos decorrentes do inadimplemento, sendo certo que a positivação do instituto traria uma maior segurança às partes e aos julgadores. Por fim, utilizando-se o método da análise econômica do direito, constatou-se que a regra da mitigação pode ser utilizada enquanto norma orientadora que disciplina o usar da riqueza social, fomentando a cooperação que deve existir entre os indivíduos a fim de evitar o desperdício de recursos econômico e socialmente relevantes

Through a case study conducted in India, of a Swedish fashion company, this thesis aims to investigate how Corporate Social Responsibility (CSR) can mitigate risks in a global fashion supply chain. By investigating CSR activities carried out by a Swedish fashion brand with its suppliers in India, the thesis shows both benefits and obstacles regarding CSR implementation. Data has been collected mostly through semi-structured interviews in both Sweden and in India with CSR managers, Indian production office, suppliers and through factory observations. The data has been analyzed with theories regarding risks in the supply chain and CSR related theories such as the triangle of Carroll. By investigating benefits and obstacles regarding implementation with suppliers, risks connected to social issues in the supply chain are highlighted. The observations showed the problematic issue of a gap between CSR communication in Sweden and how the implementations are interpreted locally. The research shows that CSR, if implemented correctly, mitigates certain risks mainly connected to brand reputation and health and safety among workers. It is further concluded that there are major issues in implementing CSR further down the supply chain than the first tier of suppliers. Lack of transparency through the supply chain challenges the company’s sustainability work and exposes vulnerabilities in the supply chain. Therefore, the Swedish fashion company is still at risk from its supply chain. / Program: Textilekonomutbildningen

With the atmospheric concentration of carbon dioxide steadily increasing and little sign of a reduction in fossil fuel demand worldwide, there is a well-established need for an alternative strategy for dealing with carbon emissions from energy production. One possible solution is the accelerated weathering of ultramafic rocks. Accelerated weathering is an environmentally benign route to a thermodynamically and kinetically stable form of carbon. The chemistry is based on naturally occurring reactions and the raw materials are abundant across the earth's surface. However, the reactions are relatively slow, and achieving reaction rates sufficient to match the carbon dioxide production rate at an energy conversion facility is challenging. This work addresses a number of the challenges facing the integration of accelerated weathering with energy conversion, and presents one view of how the integration could be achieved. This work begins by developing a suite of tools necessary for investigating the dissolution and precipitation of minerals. Chapter 2 starts with a description of the minerals that will be evaluated, and then goes on to develop the techniques that will be used. The first is a differential bed reactor, which is used for measuring the dissolution rates of minerals under tightly controlled conditions. Next a bubble column reactor is developed for the investigating the adsorption of carbon dioxide and the precipitation of mineral carbonates in a single vessel. These techniques, together with a batch reactor for studying direct carbonation reactions, constitute a comprehensive set of tools for the investigation of accelerated mineral weathering. With the necessary techniques developed and proven, Chapter 3 addresses the first challenge faced by accelerated mineral weathering; the dissolution rate of magnesium from a silicate mineral. While the dissolution of this mineral is thermodynamically favorable, the kinetics are prohibitively slow. It is thought that this is because silica from the mineral tends to accumulate on the particle surface creating a passivation layer, which limits the reaction rate of the mineral. In this work, the effects of a combination of chemical chelating agents, catechol and oxalate, are evaluated for their ability to circumvent this passivation layer. The results indicate that catechol and oxalate modify the passivation layer as it forms, both accelerating the dissolution rate of the mineral and maintaining pore volume, leading to greater dissolution rates. This pore modification process is proposed as the primary mechanism by which catechol affects the passivation layer. The combination of catechol and oxalate under acidic conditions is also shown be effective when the ambient solution approaches the saturation point of silica. Finally, the chelating does not impede the precipitation of carbonate products, a critical hurdle for a carbon storage process. The chelating agent work is extended in Chapter 4, with a sensitivity study that evaluates the response of the dissolution rate to changes in both pH and the concentration of the chelating agents. Oxalate and pH are found to exhibit a strong influence on the mineral dissolution rate, while the effect of catechol is more apparent after significant dissolution has taken place. These observations are in agreement with the model of passivation layer modification proposed. In addition, some alternatives to the chelating agent catechol are evaluated. It is found that when used in combination with oxalate, these alternatives appeared equivalent to catechol, but alone they had only a minor effect. Catechol was also noted to have a significant effect on the dissolution rate of iron from the silicate mineral, and a mechanism for this effect was proposed. The direct adsorption of carbon dioxide and precipitation of solid carbonates in a single reaction step presents another challenge for accelerated mineral carbonation. In general, the magnesium carbonates formed at ambient pressure and moderate temperatures tend to be hydrated, and at times contain unused hydroxides, leading to inefficiencies in both transport and storage. It is shown in Chapter 5 that by seeding reaction vessels with the anhydrous form of magnesium carbonate, it is possible to grow this desired phase with minimal formation of the metastable hydrated phases. The formation of this phase is primarily limited by the precipitation rate, but in some situations, carbon dioxide hydration kinetics and magnesium hydroxide precipitation kinetics also play a role. In Chapter 6, these developments in both magnesium silicate dissolution and carbonate precipitation are combined into a proposed technology for the direct capture and storage of carbon dioxide. This application of accelerated mineral weathering is shown to significantly reduce the carbon emissions of an energy conversion technology through life cycle assessment. This novel approach to the mitigation of carbon emissions presents a compelling argument for the continued development of accelerated mineral weathering as a combined carbon capture and storage technology.

Rising concentration of CO2 in the atmosphere is attributed to increasing consumption of fossil fuels. One of the most effective mechanisms to store CO2 captured from power plants is via geological injection of CO2 into formations that contain calcium and magnesium silicate and alumino-silicate minerals and rocks. The mechanism that ensures permanent storage of CO2 within rocks is mineral carbonation. When CO2 is injected into mineral or rock formations rich in calcium or magnesium silicates, they react with CO2 to form calcium or magnesium carbonates, which is also known as carbon mineralization. Calcium and magnesium carbonates are stable and insoluble in water. However, the kinetics of in-situ mineral carbonation involve CO2 hydration, mineral dissolution and formation of carbonates, and the relative rates of these phenomena when coupled, are not very well understood. In this study, the coupled interactions of CO2-reaction fluid-minerals were investigated to determine the optimal conditions for carbon mineralization, and to identify the chemical and morphological changes in the minerals as they react to form carbonates. Carbon mineralization in various minerals and rocks such as olivine ((Mg,Fe)2SiO4)), labradorite ((Ca, Na)(Al, Si)4O8), anorthosite (mixture of anorthite (CaAl2Si2O8), and basalt (rock comprising various minerals) were studied at high temperatures (Tmax = 185 oC) and high partial pressures of CO2 (PCO2, max = 164 atm) which are relevant for in-situ conditions. These minerals and rocks differ considerably in their chemical compositions and reactivity with CO2. A systematic comparison of the effects of reaction time, temperature, partial pressure of CO2, and fluid composition on the conversion of these magnesium and calcium bearing minerals and rocks showed that olivine was the most reactive mineral followed by labradorite, anorthosite, and basalt, respectively. Previous studies at Albany Research Center (Gerdemann et al., 2007; O'Connor et al., 2004) reported that a solution of 1.0 M NaCl + 0.64 M NaHCO3 was effective in achieving high extents of carbonation in olivine, heat-treated serpentine, and wollastonite. However, the independent effects of NaCl and NaHCO3 and their role in mineral carbonation were not sufficiently explained. In this study, the role of varying concentrations of NaCl and NaHCO3 on carbon mineralization of various minerals was elucidated. NaHCO3 buffered the pH and served as a carbon carrier, resulting in higher carbonate conversions. Except in the case of olivine, NaCl had a negligible effect on enhancing mineral carbonation. Unlike NaHCO3, NaCl does not buffer the pH or serve as a carbon carrier, but Cl- may serve as a weak chelating agent can complex with Mg or Ca in the mineral matrix to enhance dissolution. The competing effects of ionic strength and pH swings as the mineral dissolves and carbonation further complicate the role of NaCl on mineral carbonation. Based on the experimental methodologies developed to study carbon mineralization in minerals and rocks at high temperatures and pressures, alternative applications such as the remediation of hazardous alkaline wastes such as asbestos containing materials were identified. Asbestos is composed of chrysotile, a fibrous hydrated magnesium silicate mineral and a form of serpentine known to cause respiratory illnesses. By treating asbestos containing materials with CO2 in the presence of 0.1 M Na-oxalate, dissolution of chrysotile and precipitation of newer phases such as glushinkite (Mg(C2O4)* 2H2O) and magnesite (MgCO3) occurred, which reduced the chrysotile content in asbestos. Based on the methodologies for studying mineral dissolution and carbonation kinetics, and coupled mineral dissolution and carbonation behavior, a scheme for connecting laboratory scale experiments with simulations to estimate the uncertainties associated with carbon mineralization was developed. The effects of temperature, different dissolution rates, and varying levels of surface area changes due to passivation or reactive cracking on the rates of carbon mineralization were simulated using PhreeqC, a computer program developed for geochemical speciation calculations (Parkhurst & Appelo, 1999). Various studies proposed that microfractures and cracks may occur in geologic formations due to the extensive growth of carbonate crystals (Kelemen & Hirth, 2012; Kelemen & Matter, 2008; Matter & Kelemen, 2009; Rudge et al., 2010). Other studies have suggested that the formation of carbonates may plug the pore spaces and limit further reactivity (Hövelmann et al., 2012; King et al., 2010; Xu et al., 2004). The effects of changes in surface area due to the formation of microfractures or passivation due to carbonate growth on the rates of carbon mineralization were also simulated. Overall the results of these studies demonstrate the effect of various parameters on carbon mineralization and how these parameters can be connected to predict CO2 storage in mineral formations. The frameworks to connect laboratory scale experiments with simulations to determine carbon mineralization rates and to assess the risks associated with CO2 injection in reactive formations, can be used to direct future research efforts to predict the fate of injected CO2 with greater accuracy for sensor placement and optimization of CO2 monitoring technologies.

This dissertation describes methodologies for evaluating a set of anticipated and recommended energy infrastructure changes essential to achieving deep greenhouse gas emissions reductions in a dense urban area: Deep penetration of grid-connected wind power, widespread adoption of electric heat pumps, multiple potential services from extensive deployment of distributed generation, and increasing focus on auxiliary energy in heating and cooling systems as cities continue to grow in population and height. The focus of the research presented here was New York City and the surrounding New York State electricity supply infrastructure. After developing a wind power model based on an NREL model wind data set, a linear program model showed that after passing a low-curtailment threshold of 10 GW, energy-related wind power curtailment is driven largely by continuous operation of baseload generation and misalignment of winter wind power peaks and existing summer electricity demand peaks. Separate analyses showed the potential for increase wind-generated electricity utilization through increased use of heat pumps in New York City. A suite of models was developed to assess the zonal effects in New York City of deep statewide penetration of wind power and widespread adoption of electric heat pumps in New York City. New York City was found to have highly fluctuating net loads in deep wind penetration scenarios. Further, with large amounts of existing space heating demand replaced by heat pumps, the increased winter electricity demand peaks occurred infrequently enough that the additional generation capacity required to meet those loads would have a capacity factor well less than 1%. Small-scale, natural gas-fueled internal combustion engines deployed as distributed generation were shown to improve the ability of the system to respond to load fluctuations, to be a more economical option than new large centralized generators at the low capacity factor, and to reduce overall system gas usage due to mitigating part-load effects and startup fuel requirements. This distributed generation, which could in reality also include combined heat and power systems as well as battery storage standing alone, connected to rooftop solar or in electric vehicles, also has potential system resilience benefits. The last research effort described here included long-term monitoring of a high-rise mixed use building’s hydronic system before and after a retrofit of hydraulic equipment. Significant annual reductions of 40% energy usage for pumping were computed, primarily due to part-load flow control effects. Analysis of the monitoring data, as well as computations related to theoretical performance of hydraulic networks, showed that this approach also has potential to reduce peak loads, particularly in high-rise buildings.

As the role of cities in addressing climate change has been increasingly recognized over the past two decades, the idea of a low-carbon city becomes a dominant framework to organize urban governance and envision a sustainable urban future. It also becomes a development discourse in the less developed world to guide the ongoing urbanization process. China’s efforts toward building low-carbon cities have been inspiring at first and then obscured by the halt or total failure of famous mega-projects, leading to a conclusion that Chinese low-carbon cities compose merely a strategy of green branding for promoting local economy. This conclusion, however, largely neglects the profound implications of the decarbonization discourse for the dynamics between the central and local governments, which together determine the rules and resources for development practices. The conclusion also hinders the progressive potentials of the decarbonization discourse in terms of introducing new values and norms to urban governance. This dissertation approaches “low-carbon cities” as a part of the decarbonization discourse and employs a discourse-institutional analysis to investigate the relationships between discourse, institutional arrangement, and socio-political resources for development activities. Through an examination of the Shenzhen International Low-Carbon City (SILCC), the dissertation answers three questions: (1) How does the framework of a low-carbon city affect a specific urban development project? (2) What is the role of the state (local/national) in promoting low-carbon development? and (3) What is the influence of the decarbonization discourse on institutions and norms of urban governance? Evidence was gathered during 2014-2017 from three fieldtrips, 39 interviews and the review of government documents and other archives. The dissertation highlights how different levels of government became entangled in developing a local area and how, in doing so, the proponents continuously searched for ways of ‘positioning’ their initiative in discourses that would attract higher level government support, maintain local coalitions, and entice international attention and investment. In this regard, low-carbon cities are a state discursive project. Rather than an established material goal, a low-carbon city is an evolving process in which the decarbonization discourse introduces a new set of values, metrics and governing logics into development practices and redefines the legitimacy and accountability of urban development. Furthermore, the local state leverages the interpretive flexibility within the decarbonization discourse through strategies including carbon labeling, weak carbonization, and carbon exceptionalism. Consequently, the state takes a strategic position to reconfigure the state-society as well as the environment-economy relationships.

One of the key requirements of fifth generation (5G) systems is having a connection to mobile networks without interruption at anytime and anywhere, which is also known as seamless connectivity. Nowadays, fourth generation (4G) systems, Long Term Evolution (LTE) and Long Term Evolution Advanced (LTE-A), are mature enough to provide connectivity to most terrestrial mobile users. However, for airborne mobile users, there is no connection that exists without interruption. According to the regulations, mobile connectivity for aircraft passengers can only be established when the altitude of the aircraft is above 3000 m. Along with demands to have mobile connectivity during a flight and the seamless connectivity requirement of 5G systems, there is a notable interest in providing in-flight wireless services during all phases of a flight. In this thesis, many issues related to the deployment and operation of the onboard systems have been investigated. A measurement and modelling procedure to investigate radio frequency (RF) propagation inside an aircraft is proposed in this thesis. Unlike in existing studies for in-cabin channel characterization, the proposed procedure takes into account the deployment of a multi-cell onboard system. The proposed model is verified through another set of measurements where reference signal received power (RSRP) levels inside the aircraft are measured. The results show that the proposed model closely matches the in-cabin RSRP measurements. Moreover, in order to enforce the distance between a user and an interfering resource, cell sectorization is employed in the multi-cell onboard system deployment. The proposed propagation model is used to find an optimum antenna orientation that minimizes the interference level among the neighbouring evolved nodeBs (eNBs). Once the optimum antenna deployment is obtained, comprehensive downlink performance evaluations of the multi-cell, multi-user onboard LTE-A system is carried out. Techniques that are proposed for LTE-A systems, namely enhanced inter-cell interference coordination (eICIC) and carrier aggregation (CA), are employed in the system analysis. Different numbers of eNBs, antenna mounting positions and scheduling policies are examined. A scheduling algorithm that provides a good tradeoff between fairness and system throughput is proposed. The results show that the downlink performance of the proposed onboard LTE-A system achieves not only 75% of the theoretical limits of the overall system throughput but also fair user data rate performance, irrespective of a passenger's seat location. In order to provide the seamless connectivity requirement of 5G systems, compatibility between the proposed onboard system deployment and the already deployed terrestrial networks is investigated. Simulation based analyses are carried out to investigate power leakage from the onboard systems while the aircraft is in the parked position on the apron. According to the regulations, the onboard system should not increase the noise level of the already deployed terrestrial system by 1 dB. Results show that the proposed onboard communication system can be operated while the aircraft is in the parked position on the apron without exceeding the 1 dB increase in the noise level of the already deployed terrestrial 4G network. Furthermore, handover parameters are obtained for different transmission power levels of both the terrestrial and onboard systems to make the transition from one system to another without interruption while a passenger boards or leaves the aircraft. Simulation and measurement based analyses show that when the RSRP level of the terrestrial system is below -65 dBm around the aircraft, a boarding passenger can be smoothly handed over to the onboard system and vice versa. Moreover, in order to trigger the handover process without interfering with the data transmission, a broadcast control channel (BCCH) power boosting feature is proposed for the in-cabin eNBs. Results show that employing the BCCH power boosting feature helps to trigger the handover process as soon as the passengers step on board the aircraft.

A reação química entre os hidróxidos alcalinos presentes no cimento e fases minerais reativas presentes no agregado dá origem a um gel sílico-alcalino que ao adsorver água se expande, podendo causar expansão e fissuração do concreto, afetando a sua durabilidade. Este fenômeno é chamado de reação álcali-agregado (RAA) e embora seja conhecido há aproximadamente 70 anos no meio técnico, e principalmente estar relacionado às grandes barragens e estruturas de concretos diversas de Usina hidrelétricas, nos últimos anos outros tipos de estruturas têm sido afetadas, inclusive fundações de edifícios, deixando ainda mais o problema em evidência. As medidas preventivas para esta reação já são conhecidas há muito tempo e aplicadas rotineiramente em estruturas de usinas hidrelétricas quando se tem agregados reativos, sendo recentemente normalizadas no Brasil. Porém, ainda existem grandes carências em se combater o fenômeno quando já se encontra instalado no concreto. Diante do exposto, este trabalho, desenvolvido dentro do programa de P&D de Furnas/ANEEL, teve como principal objetivo verificar a potencialidade de compostos a base de Silanos através de testes laboratoriais com vistas à aplicação em concretos contendo agregados reativos na tentativa de minimizar as expansões residuais em estruturas que já se encontram afetadas. As atividades desenvolvidas contemplam ensaios em barras de argamassas que foram tratadas, em três etapas distintas, com compostos a base de silanos. A primeira etapa foi desenvolvida como projeto piloto, e seus resultados serviram de apoio para a realização das etapas seguintes. Nas segunda e terceira etapas foi verificada a atuação dos produtos na prevenção e na mitigação da RAA, respectivamente. Os resultados obtidos na primeira etapa não foram satisfatórios, pois as expansões foram maiores do que as da referência. Já para a segunda e terceira etapas, os procedimentos para aplicação dos tratamentos previram que as barras fossem tratadas sem que estivessem previamente expostas à solução de NaOH, conforme realizado na primeira etapa, o que possivelmente ocasionou o acréscimo das expansões, sem a eficiência do produto. Os resultados obtidos nessas etapas se mostraram eficientes tanto na prevenção quanto na mitigação das expansões residuais da RAA e, embora o lítio produza uma maior eficiência na redução das expansões, os tratamentos à base de silano, e principalmente do tipo octiltrietoxisilano, mostraram muito promissores. Após o lítio, o tratamento à base do silano OCTEO, no teor de 10%, com o surfactante tipo DMSO, em aplicação múltipla, se mostrou mais eficiente. Para complemento da parte experimental da pesquisa, foram realizados ensaios de absorção de água por imersão e análises por microscopia eletrônica de varredura e verificou-se o efeito dos produtos de tratamento nos poros das argamassas. / The chemical reaction between cement alkaline hydroxides and reactive silica present in some aggregates produces an alkaline silicate gel that expands when it adsorbs water and can cause concrete expansion and cracking, thereby affecting durability. This phenomenon is known as alkali-aggregate reaction (AAR) and was first detected over 70 years ago as the cause of deterioration especially in large dams and a number of other concrete structures in hydroelectric power plants in general. In recent years, AAR has also been noted in other types of structure, such as building foundations, bringing the problem more dramatically to the fore. Preventive measures for AAR have long been known and are routinely applied in hydroelectric power plant structures when there are reactive aggregates. These measures have been recently standardized in Brazil. Nevertheless there are still flaws in our knowledge regarding how to mitigate expansion when this phenomenon is already present in the concrete. Considering these aspects, the main purpose of this study, developed within Furnas/ANEEL Research and Development Program, is to verify, at laboratory level, the mitigating potential of silane compounds in residual expansion in affected mortars which contain reactive aggregates. Assays were performed on bars of mortar treated with silane compounds in three different stages. The first stage was developed as a pilot study with results serving as support for the following stages. The second and third stages verified the activity of the products in the prevention and mitigation of AAR, respectively. The results obtained in the first stage were unsatisfactory as the expansions were greater than the references. The second and third stage treatments required bars not previously exposed to NaOH, differently from the first stage and which may have been the cause of the increased expansion and product inefficiency. The results in these stages proved satisfactory both in preventing and mitigating AAR residual expansions, and although lithium is more efficient in reducing expansions, silane based treatments, mainly the octyltriethoxysilane types proved most promising. Following lithium, the most efficient treatment was 10% content OCTEO silane with a DMSO type surfactant applied in multiple layers. To complement the experimental part of the study, assays on water absorption through immersion were performed as well as scanning electron microscopy to verify the effect of the treatment products on the mortar pores.