O presente trabalho testa uma alternativa de ajuste da estrutura a termo da taxa de juros brasileira bem como a sua previsão através de uma variação do modelo Diebold e Li (2006) focando principalmente em seu fator de decaimento exponencial. Esta variação do fator de decaimento ocorre distintamente em dois momentos do trabalho, primeiramente no ajuste da curva e após quando da previsão desta. No ajuste, o encontro deste parâmetro é feito através de ferramenta computacional, buscando o fator de decaimento que reduz a diferença de mínimos quadrados em relação aos pontos originais capturados no mercado de juros futuro brasileiro em conjunto dos três outros fatores do modelo. A previsão da estrutura a termo utiliza modelos auto regressivos para estimar as próximas curvas no horizonte de um período. A importância deste estudo reside em conhecer a aderência do modelo proposto à curva de juros brasileira testando sua eficiência quando utilizados os pressupostos enunciados. / This study tests an alternative adjustment of the term structure of Brazilian interest rate and its prediction through a variation of the Diebold and Li (2006) model focusing mainly on his exponential decay factor. The variation of the decay factor occurs in two distinct moments of this work, in the curve fitting and after this in the forecasting. During the setting, this parameter is mesured through computational tool, seeking the decay factor that reduces the difference in least squares relative to the original points captured in the Brazilian market future interest together the other three factors of the model. To Forecast the term structure is used auto regressive models to estimate the upcoming curves. The importance of this study lies in knowing the adherence of the proposed to the Brazilian yield curve testing its efficiency when utilized the assumptions listed in the model.

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Orientador: Vera Lucia Gil da Silva Lopes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-10T16:23:58Z (GMT). No. of bitstreams: 1 Monlleo_IsabellaLopes_D.pdf: 6807937 bytes, checksum: a28121a53a2b35d8afe389692c026003 (MD5) Previous issue date: 2008 / Resumo: As primeiras ações para inclusão da atenção a pessoas com anomalias craniofaciais (ACF) no Sistema Único de Saúde (SUS) ocorreram na década de 1990 e culminaram com a criação da Rede de Referência no Tratamento de Deformidades Craniofaciais (RRTDCF). Esta rede foi avaliada por Monlleó em 2004, momento em que foram identificados centros de atendimento a pessoas com ACF vinculados ao SUS, mas não à RRTDCF. Objetivos: (1) avaliar os centros de ACF não-RRTDCF; (2) discutir a política de atenção à saúde para ACF do Brasil; (3) elaborar cadastro dos centros estudados e (4) elaborar proposta de banco de dados de fendas orofaciais para o Brasil. Resultados: 82 centros de atendimento a pessoas com ACF participaram da avaliação. Estes centros estão concentrados no Sudeste e em universidades e compreendem serviços isolados, multiprofissionais e associações de pais. Apenas seis serviços multiprofissionais seguem critérios internacionais de composição de equipes. Nestes, odontólogos e cirurgiões são os especialistas mais freqüentes. Geneticistas clínicos estão envolvidos com aconselhamento genético em 35 serviços, enquanto em 30, outros profissionais realizam esta atividade. Sessenta e dois centros aderiram ao cadastro proposto. O banco de dados consiste em um projeto de registro clínico e familial de pessoas com fendas orofaciais atendidas em unidades da RRTDCF. Em torno deste, cinco projetos satélites foram elaborados: (1) banco de DNA; (2) avaliação da organização interna das unidades; (3) banco de profissionais de saúde e de protocolos de tratamento; (4) estudos de seguimento pós-cirúrgico, morbidade e mortalidade; (5) avaliação de satisfação dos usuários. Conclusões: os centros não-RRTDCF se sobrepõem à RRTDCF quanto à distribuição, procedimentos, clientela e financiamento. Iniqüidades, disparidades regionais e falta de integralidade permanecem como problemas. Acredita-se que a superação desses problemas requer a reformulação da política de atenção a pessoas com ACF e, para tanto, apresentam-se diretrizes. O cadastro de centros é uma ferramenta pública para minorar dificuldades de acesso a informações. Por sua vez, o banco de dados poderá fornecer subsídios para avaliação contínua dos serviços e para a reformulação da política de saúde para ACF no SUS / Abstract: Health care for persons with craniofacial anomalies (CFA) officially started in Brazil in the nineties. It was consolidated through the Reference Network for Craniofacial Treatment (RRTDCF). The RRTDCF was evaluated by Monlleo in 2004 when several non-RRTDCF units operating in the Unified Health System (SUS) were identified. Aims: (1) to evaluate health care provided through non-RRTDCF units; (2) to inform the debate about craniofacial health care policy in Brazil; (3) to build up a record on CFA units; (4) to build up a Brazilian database on orofacial clefts. Results: 82 non-RRTDCF units took part of the survey. They are mainly located in the southeast, and in universities. They are funded by the government and comprise independent clinics, multiprofessional teams and parental associations. Only 6 multiprofessional units meet the international criteria for minimal CFA teams. Clinical geneticists are involved in genetic counselling in 35 units, however in 30 it is provided by untrained professionals. Sixty two units agreed to participate in the national record proposed. The Brazilian database on orofacial clefts was designed to record clinical and familial information on patients assisted through the RRTDCF. Additionally, five satellite projects were built: (1) biobank of DNA; (2) general care assessment; (3) database of healthcare professionals and assessment of treatment protocols; (4) follow-up studies on surgical treatment and morbidity/mortality and (5) patient/parent satisfaction studies. Conclusion: non-RRTDCF units overlap RRTDCF regarding distribution, treatment provided, type of CFA treated, and funding. The current system does not ensure equity and coordination of care, and keeps up regional disparities. It is believed that these problems may be overcome through changes in the current national health policy for CFA in Brazil and suggestions are given in this regard. The national record on CFA units is a tool in the public interest and can improve equity of access to services. The database, on the other hand, is an achievable strategy to set up appraisal and audit systems and to support the reformulation of health policy for persons with CFA in the SUS / Doutorado / Genetica Medica / Doutor em Ciências Médicas

Over the last century, almost all of the carbon materials developed for the energy industry are derived from fossil fuels. The growing global concerns about energy needs, fossil fuels consumption, and the related environmental issues have motived scientists to find new, green and sustainable energy resources such as the wind, solar and biomass energy. Essentially, biomass-derived materials can be utilized in energy storage and conversion devices such as Li-ion batteries, fuel cells, and supercapacitors. Among the biomass resources, lignin is a high volume byproduct from the pulp and paper industry and is currently burned to generate electricity and steam. The pulp and paper industry has been searching for high value-added uses of lignin to improve its overall process economics. The importance of manufacturing valuable materials from lignin is, discussed in Chapter 2, demonstrating the need for a facile, green and scalable approach to synthesize bio-char and porous carbon for use in Li-ion batteries. From this context, lignin is first carbonized in water at 300 °C and 103 bar to produce bio-char, which is then graphitized using a metal nitrate catalyst at 900-1100 °C in an inert gas at 1 bar. Graphitization effectiveness of three different catalysts, iron, cobalt and manganese nitrates was examined. The obtained materials were analyzed for morphology, thermal stability, surface properties, and electrical conductivity. Both annealing temperature and the catalyst affects the degree of graphitization. High-quality graphitization is obtained by using Mn(NO3)2 at 900 °C or Co(NO3)2 catalysts at 1100 °C. Research on various energy storage materials for supercapacitors has grown rapidly in the recent years. Various advanced materials have been shown as a promising candidate for future’s high-energy supercapacitor electrodes. For a material in a supercapacitor electrode to be considered, it must show promising results for its specific power and energy density, electrical conductivity, surface properties, durability, surface area and pore-size distribution in order to design and develop high-performance supercapacitor devices. The industrial applications of supercapacitors have not been satisfied due to the low energy density (the commercially available supercapacitors have between 5 to 10 times less energy density than that of batteries) and moderate charge-discharge rate of supercapacitor electrode. Thus, chapter 3 was aimed to design and synthesize nitrogen-doped carbon materials that show the characteristic of high-energy and high-power density supercapacitor electrodes with a long cycle life. With this aim, organosol lignin was successfully converted into N-doped carbon materials using a two-step conversion process. The nitrogen content in the carbon was up to 5.6 wt.%. The synthesize materials exhibit high surface area up to 2957 m2/g with micro/meso porosity and a sheet-like structure. The N-doped carbon produced at 850 oC exhibited a high capacitance value of 440 F g-1 at a 1 mV s-1 scan rate and demonstrated excellent cyclic stability over 30,000 cycles in 1 M KOH. In addition, the NC-850 delivers a high energy density of 15.3 W h kg-1 and power density of 55.1 W kg−1 at 1 mV s-1. Therefore, this study suggests that N-doped carbon materials synthesized from a pulp and paper byproduct, lignin, are promising environmentally-sustainable candidates for supercapacitor applications. Challenges for commercialization of fuel cells include high operation cost, inadequate operational stability, and poisoning by H2O2. To address the challenge, costly Pt-based catalysts are needed in order to facilitate the oxygen reduction reaction (ORR) at the cathode and the hydrogen oxidation reaction (HOR) at the anode. In chapter 4, alternative metal-free ORR catalyst materials derived from lignin are studied in order to simultaneously enhance the catalytic activity, lessen the Pt dependency and reduce the excessive costs associated. Calcium sulfonate lignin was successfully converted into sulfur self-doped carbons via in-situ hydrothermal carbonization and followed by post-annealing treatment. The sulfur content in the as-prepared porous carbons is up to 3.2 wt.%. The resulting materials displayed high surface areas (up to 660 m2 g-1) with micro/meso porosity and graphitic/amorphous carbon structure. The as-prepared sulfur self-doped electrode materials (SC-850) were tested as a potential cathodic material for ORR. The number of electrons transferred per molecule was measured to be ~ 3.4 at 0.8 V, which approaches the optimum 4 electron pathway. Additionally, S-doped materials were also applied as a supercapacitor electrode material. The SC-850 electrode exhibited a high specific and volumetric capacitance values of 225 F g-1 and 300 F cm-3 at a scan rate of 0.5 A g-1. The SC-850 electrode also exhibited consistent response over 10,000 cycles at harsh conditions. It was shown that the metal-free SC-850 is a promising electrode material for supercapacitors and ORR applications. All of the studies presented in this dissertation involve the development and application of carbon-based materials derived from lignin and its application towards the Li-ion batteries, supercapacitor, and fuel cell. Insight into the applicability of lignin-derived carbon materials towards electrochemical applications is made readily available, supplemented by detailed physical, chemical and electrochemical characterization, to examine the specific factors influencing the Li-ion batteries, supercapacitor, and electrocatalysis of fuel cell activity.

Ageing mechanisms of graphite/NMC Li-ion batteries have been studied using computational methods. The purpose of the project was to investigate solid electrolyte interphase (SEI) formation and growth during cycling of the battery. The SEI layer formation was considered to be a reason for capacity fade of the battery. Irreversible consumption of cyclable Li-ions and increased resistance in the layer was considered to be the result of solid electrolyte layer formation and these two effects were studied more closely using cell modelling. The battery cycled with three cases of fast charge rates (2C, 4C and 6C) and the same discharge rate (1C) showed a thick film formation on the anode side and a higher film resistance when compared to the battery cycled with the same charge/discharge rate (1C). All investigated batteries were affected by the studied ageing mechanism, and in the case of batteries cycled with fast charge rates, the ageing was even more pronounced. The report includes a general description of Li-ion battery functionality, a summary of ageing mechanisms and a mathematical description of the electrochemistry governing the battery and implemented in the software.

To light up the world of technology, where wireless communication has bloomed to a great extend which requires a lot of data to be transmitted and received every fraction of the second a new era is coming. Electro-magnetic waves i.e., radio waves are the main way to transmit wireless data but certain limitations are there because radio waves can only support less bandwidth because of compact spectrum availability and intrusions. Visible Light Communication (VLC) has come to take way those issues. The new technology Li-Fi which stands for Light-Fidelity is a new kind of wireless communication system which uses light waves as a medium instead of radio frequency electromagnetic waves. This pro-ject presents an eco-friendly data communication system through visible light which consists of LEDs that transmit audio signals and sensor data to the receiver. A connection protection mechanism that co-operates with wireless network and visible light communication to achieve relia-bility and performance overcoming the drawbacks from the pre-existing system is proposed here.

Over the years, there has been an exponential increase in the capabilities of networks, evolving from wired networks to wireless, and finally moving towards 4G networks. This evolution has brought forth many ways in which a user can access any service, particularly accessing the Internet. From emailing and social networking to file transferring, users are on a constant venture to exploit the advantages as much as possible. Predictions show that the demand will only increase with increasing number of mobile devices and subscribers. It becomes clearer that there will be rapid growth in the demand for more energy-efficient mobile devices. However, due to relatively slow increase in the battery technologies, the mobile users' expectations were not being met. This thesis highlights few interesting points on the energy consumptions by the most common Internet browsing tasks. It then presents the measurements of energy consumption on using various network connection technologies namely Ethernet, Wi-Fi and 3G to access the Internet. The obtained data from the experiments were then analyzed to arrive at an idea on the difference in energy consumptions across various browsing tasks and access technologies. Later, it involves a survey through which critical observations with respect to power efficiency and QoE are collected. The study concludes with a picture that would help users have an insight on the technologies that they may wish to choose to connect to the Internet. It helps manufacturers understand and consider the affect of an interface on the power consumption. It also helps researchers bring better solutions of designing the network interfaces. The aim would be to reduce the energy consumption by the product components rather than struggling to design powerful batteries to meet the increasing power demands from the network components. A wise choice of networking technologies is or what is may be required to gain better energy efficiency.

We present a preliminary design for a novel neutron detection system that is compact, lightweight, and low power consuming, utilizing the CubeSat platform making it suitable for space-based applications. This is made possible using the scintillating crystal lithium indium diselenide ((LiInSe2)-Li-6), the first crystal to include Li-6 in the crystalline structure, and a silicon avalanche photodiode (Si-APD). The schematics of this instrument are presented as well as the response of the instrument to initial testing under alpha, gamma and neutron radiation. A principal aim of this work is to demonstrate the feasibility of such a neutron detection system within a CubeSat platform. The entire end-to-end system presented here is 10 cm x 10 cm x 15 cm, weighs 670 grams and requires 5 V direct current at 3 Watts.

Face aux défis du XXIème siècle concernant l'approvisionnement mondial en énergie et le réchauffement climatique, il est capital de développer des systèmes de stockage d'énergie efficaces et compétitifs. Parmi eux, la technologie Lithium-Air fait l'objet de nombreuses recherches car elle présente une densité d'énergie théorique dix fois supérieure à celle des batteries Li-ion actuellement utilisées, mais la complexité des réactions chimiques mises en jeu la cantonne au stade de la recherche. Afin d'étudier de manière fiable et reproductible les batteries Li-Air, une nouvelle cellule de test électrochimique intégrant un capteur de pression a été développée. Elle permet d'estimer la quantité de réactions parasites associées à une configuration de batterie lors du cyclage à court et long terme (> 1000 h). Une étude comparative des différents électrolytes les plus utilisés a été réalisée, révélant la différence de comportement entre ces différentes espèces ainsi que l'instabilité de l'anode composée de lithium métallique. Nous avons donc abordé le remplacement de l'anode de lithium par une électrode de silicium pré-lithié. En étudiant l'influence de différentes techniques de pré-lithiation sur des électrodes contenant des particules de Si oxydées en surface, un phénomène de réduction de SiO2 en Si a été mis en évidence, apportant ainsi un gain substantiel en capacité. Les électrodes " activées " ont ensuite été utilisées en tant qu'anode dans les cellules complètes LixSi-O2. Après optimisation, la durée de vie obtenue est supérieure à 400 h (> 30 cycles), ce qui est comparable à la littérature actuelle mais toutefois limité par la présence de réactions parasites. / Supplying the world energy demand while reducing the greenhouse gases emissions is one of the biggest challenges of the 21st century; this requires the development of efficient energy storage devices enabling the utilization of renewable energies. Among them, Lithium-Air batteries are very attractive due to their high theoretical energy density – 10 times that of the current Li-ion batteries – but their development is hindered by the complexity of the chemistry at play. In order to understand such chemistry, we designed a new electrochemical test cell that integrates a pressure sensor, thereby enabling an accurate in operando monitoring of the pressure changes during charge/discharge with high reproducibility and sensitivity. Its use is demonstrated by quantifying the parasitic reactions in Li-O2 cells for various electrolytes frequently encountered in the literature. Through this comparative study, we are able to observe the phenomena currently limiting the performances of Li-O2 batteries after a long cycling (> 1000 h), such as parasitic reactions and the instability of the Li anode. To address the later issue, Li was replaced by a prelithiated silicon electrode made of Si particles oxidized in surface. We demonstrated the feasibility of enhancing both their capacity and cycle life via a pre-formatting treatment that triggers the reduction of their SiO2 coating by liberating pure Si metal. The full LixSi-O2 cells using such treated electrodes exhibit performances competing with the best analogous systems reported in the literature (> 30 cycles; more than 400 h of cycling), but the development of practical prototypes still requires to improve the cycle-life.

Between 1950s and 1990s, Hong Kong had a frenzy for writing and re-writing materials from classical literature and myths. The myth of Madame White Snake is one of the most well known stories that survived a long period of time. The earliest known version of Madame White Snake was a supernatural story in 1550, which later became a prototype of numerous subsequent versions starting in 1624. This prototype was repeatedly re-written throughout history and was also made into different genres including plays, playlets, novels, films and television dramas. One of the latest versions was written by Li Pikwah, a popular novelist in Hong Kong, in 1993, titled, Green Snake. Green Snake is a parody of Madame White Snake written from the perspective of Little Green, the servant of Madame White and an auxiliary figure in the tradition. The novel is also an autobiography of Little Green, who satirically criticizes the story of Madame White Snake in retrospect. Little Green’s autobiography is a nostalgic reflection of the past as well as a critique of the structure of the story that has survived throughout history. These implications made in the story hint at the author’s personal yearning for traditional China as a Chinese resident in Hong Kong. Her nostalgia for traditional China is not idealistic but paradoxical, because her re-writing of the story was an avenue to understand and re-negotiate her identity. Li is also well-known for her other novels, which are parodies of classical literature, traditional myth and legend. Many of these works were also made into films in the 80’s and 90’s. These novels and films were part of a phenomenon in contemporary Hong Kong literary and popular culture that tried to grasp a cultural connection with traditional China in order to embrace the return to mainland China in 1997 after a hundred years of British colonial rule. / Arts, Faculty of / Asian Studies, Department of / Graduate