Thèses : « BCBS »

1

Hilmersson, Markus. « A Study Evaluating the Liquidity Risk for Non-Maturity Deposits at a Swedish Niche Bank ». Thesis, KTH, Matematisk statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-273594.

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Since the 2008 financial crisis, the interest for the subject area of modelling non-maturity deposits has been growing quickly. The area has been widely analysed from the perspective of a traditional bank where customers foremost have transactional and salary deposits. However, in recent year the Swedish banking sector has become more digitized. This has opened up opportunities for more niche banking actors to establish themselves on the market. Therefore, this study aims to examine how the theories developed and previously used in modelling liquidity volumes at traditional banks can be used at a niche bank focused on savings and investments. In this study the topics covered are short-rate modelling using Vasicek's model, liquidity volume modelling using SARIMA and SARIMAX modelling as well as liquidity risk modelling using an approach developed by Kalkbrener and Willing. When modelling the liquidity volumes the data set was divided depending on account and customer type into six groups, for four out of these the models had lower in and out of set prediction errors using SARIMA models for only two of the six models were there improvements made to the in and out of set prediction error using SARIMAX models. Finally, the resulting minimization of liquidity volume forecasting 5 years in the future gave reasonable and satisfactory results.
Sedan finanskrisen 2008 har intresset kring ämnesområdet gällande modellering av inlåningsvolymer utan en kontrakterad förfallodag ökat snabbt. Området har analyserats i stor utsträckning från perspektivet av en traditionell bank där kunder har framförallt transaktions- och lönekonton. De senaste åren har den Svenska banksektorn blivit mer digitaliserad. Detta har öppnat upp möjligheter för nischbanker att etablera sig på marknaden. Därför ämnar denna studie att undersöka hur teorier som har utvecklats och tidigare använts på traditionella banker för att modellera likviditetsvolymer kan användas på en nischbank som är fokuserad på sparande och investeringar. I denna studie modelleras korträntor med Vasicek's modell, likviditetsvolymer med SARIMA och SARIMAX modeller och likviditetsrisk med en modell utvecklad av Kalkbrener och Willing. För modelleringen av likviditetsvolymer delades likviditetsdatan upp i sex grupper baserat på konto- och kund typ. För fyra av dessa data set gav SARIMA-modeller lägre prediktionsfel och endast för två av de sex grupperna gav SARIMAX-modeller bättre resultat. Slutligen så gav den resulterande minimeringen av nödvändiga likviditetsvolymer på en 5 årig horisont rimliga och tillfredsställande resultat.

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Ramos, Mariana Alexandra Cravo. « O impacto do Data Lake nos sistemas de reporting do setor bancário ». Master's thesis, Instituto Superior de Economia e Gestão, 2021. http://hdl.handle.net/10400.5/23476.

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Mestrado Bolonha em Gestão de Sistemas de Informação
O setor bancário é caracterizado pela forte regulamentação e supervisão, bem como pela existência de inúmeros sistemas de informação heterogéneos, os quais foram sido adquiridos e adaptados ao longo do tempo. Por outro lado, a enorme quantidade de dados, definida por Big Data, trouxe novos desafios ao processamento e integração dos dados e, consequentemente, à sua qualidade. O mercado está a mudar e o setor bancário não é exceção. Para dar resposta à falta de qualidade dos dados, o Basel Committee on Banking Supervision (2013), (BCBS), definiu 14 princípios, nomeados como BCBS 239, que devem ser atendidos por este setor. No entanto, estes princípios são vagos e não existe nenhuma orientação sobre os métodos a utilizar para agir em conformidade com o regulador. Por este motivo, as questões de investigação são: como é que o Data Lake impacta a concretização dos princípios BCBS 239? De que forma está a organização em conformidade com os princípios do BCBS 239? Quais são as vantagens e os desafios do Data Lake do ponto de vista da organização em estudo? Para dar resposta, foi desenvolvido um case study com recurso a entrevistas semiestruturadas a colaboradores de um banco que atua no mercado português. Para a análise de dados foi utilizado o programa MAXQDA. Os resultados obtidos permitem identificar que a existência de várias fontes de dados e de processos não automatizados são os desafios com maior expressão nos atuais processos de reporting. Além disso, é possível reconhecer que as principais vantagens do Data Lake advêm do facto de este ser um repositório único, potencializar a uniformização de conceitos de negócio e melhorar a eficiência organizacional. Por outro lado, a ambiguidade de conceitos é um obstáculo que tem de ser ultrapassado, de forma a garantir a existência de um modelo de governo de dados. Em suma, o Data Lake é um excelente meio para cumprir o BCBS 239, em especial, no desenvolvimento da arquitetura de dados e infraestrutura de TI, melhorando, consequentemente, a qualidade dos dados.
The banking sector is characterized by strong regulation and supervision, as well as the existence of numerous heterogeneous information systems, which have been acquired and adapted over time. On the other hand, the enormous amount of data, conceptualized as Big Data, brought new challenges to data processing and integration processes and, consequently, its quality. The market is changing, and the banking sector is no exception. Therefore, to respond to the lack of data quality, the Basel Committee on Banking Supervision (2013), (BCBS), defined the BCBS 239, which compilates 14 principles that the companies of this sector must meet. However, these principles are vague, and there is no guidance on the methods to be used to comply with regulators. For this reason, the research questions are: how does Data Lake impact the implementation of BCBS 239 principles? How is the organization compliant with the BCBS 239 principles? What are the advantages and challenges of the Data Lake from the point of view of the organization? A case study was developed using semi-structured interviews with current employees of a bank operating in the portuguese market to investigate this research topic. Moreover, the data analysis was conducted via the MAXQDA program. The results obtained allowed to acknowledge that the existence of a wide range of data sources and non-automated processes is the most significant challenge in current reporting processes. Furthermore, it was possible to recognize that the main advantages of Data Lake focus on the fact that (1) it is a single repository; (2) it enhances the standardization of business concepts and consequently, (3) improves organizational efficiency. On the contrary, the present study also revealed that the ambiguity of concepts is a critical obstacle that must be overcome to guarantee the existence of a data governance model. In short, Data Lake is a powerful way to meet BCBS 239, in particular, in developing data architecture and IT infrastructure, thereby improving data quality.
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Stavrén, Fredrik, et Nikita Domin. « Modeling of non-maturing deposits ». Thesis, KTH, Matematisk statistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-252302.

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The interest in modeling non-maturing deposits has skyrocketed ever since thefinancial crisis 2008. Not only from a regulatory and legislative perspective,but also from an investment and funding perspective.Modeling of non-maturing deposits is a very broad subject. In this thesis someof the topics within the subject are investigated, where the greatest focus inon the modeling of the deposit volumes. The main objective is to providethe bank with an analysis of the majority of the topics that needs to be cov-ered when modeling non-maturing deposits. This includes short-rate model-ing using Vasicek’s model, deposit rate modeling using a regression approachand a method proposed by Jarrow and Van Deventer, volume modeling usingSARIMA, SARIMAX and a general additive model, a static replicating port-folio based on Maes and Timmerman’s to model the behaviour of the depositaccounts and finally a liquidity risk model that was suggested by Kalkbrenerand Willing. All of these models have been applied on three different accounttypes: private transaction accounts, savings accounts and corporate savingsaccounts.The results are that, due to the current market, the static replicating portfoliodoes not achieve the desired results. Furthermore, the best volume model forthe data provided is a SARIMA model, meaning the effect of the exogenousvariables are seemingly already embedded in the lagged volume. Finally, theliquidity risk results are plausible and thus deemed satisfactory.
Intresset för att modellera inlåningsvolymer utan en kontrakterad förfallodaghar ökat markant sedan finanskrisen 2008. Inte bara sett utifrån ett perspek-tiv att uppfylla krav som ställs av tillsynsmyndigheter, men också sett utifrånbankens investerings-och finansieringsperspektiv.Målet med det här arbetet är att förse banken med en analys av majoritetenav de olika områdena som man behöver ta hänsyn till när man ska model-lera inlåningar utan förfallodatum, men med ett fokus på volymmodellering.I den här rapporten modelleras räntor (kortränta och kontoränta), kontovoly-merna, kontobeteendet samt likviditetsrisken. Detta görs med hjälp av Vasicekför korträntan, en regressionsmetod samt en metod som föreslagits av Jarrowoch Van Deventer för kontoräntan, SARIMA, SARIMAX och en generell ad-ditiv regressionsmetod för volymerna, en statisk replikeringsportfölj baseradpå Maes och Timmermans modell för att imitera kontona och slutligen så mo-delleras likviditetsrisken med ett ramverk som föreslagits av Kalkbrener ochWilling. Alla dessa nämnda modeller appliceras, där det är möjligt, på de treolika kontotyperna: privatkonton, sparkonton samt företagssparkonto.Resultatet är att räntemodelleringen samt replikeringsportföljen inte ger ade-kvata resultat på grund av den rådande marknaden. Vidare så ger en SARIMA-modell den bästa prediktionen, vilket gör att slutsatsen är att andra exogenavariabler redan är inneslutna i den fördröjda volymvariabeln. Avslutningsvisså ger likviditetsmodellen tillfredsställande resultat och antas vara rimlig.

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Randhawa, Tarlochan Singh. « Incorporating Data Governance Frameworks in the Financial Industry ». ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/6478.

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Data governance frameworks are critical to reducing operational costs and risks in the financial industry. Corporate data managers face challenges when implementing data governance frameworks. The purpose of this multiple case study was to explore the strategies that successful corporate data managers in some banks in the United States used to implement data governance frameworks to reduce operational costs and risks. The participants were 7 corporate data managers from 3 banks in North Carolina and New York. Servant leadership theory provided the conceptual framework for the study. Methodological triangulation involved assessment of nonconfidential bank documentation on the data governance framework, Basel Committee on Banking Supervision's standard 239 compliance documents, and semistructured interview transcripts. Data were analyzed using Yin's 5-step thematic data analysis technique. Five major themes emerged: leadership role in data governance frameworks to reduce risk and cost, data governance strategies and procedures, accuracy and security of data, establishment of a data office, and leadership commitment at the organizational level. The results of the study may lead to positive social change by supporting approaches to help banks maintain reliable and accurate data as well as reduce data breaches and misuse of consumer data. The availability of accurate data may enable corporate bank managers to make informed lending decisions to benefit consumers.

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Manninen, I. (Iikka). « Gamified BCSS for healthier food choices:case implicity ». Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201806022430.

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The main aim of this thesis was to design a persuasive and gamified version of the implicit association test. The goal of the mobile application is to help people adopt healthier eating habits. Poor diet is a major factor in many diseases and contributes negatively to life quality. Additionally, healthcare systems and employers are also affected in the form of production losses and treatment costs. The underlying research aim is to utilize the artefact to investigate whether exposing a user to possible cognitive dissonances in thinking can lead to reflection. Reflection in turn can lead to reduction of dissonances and in turn, behaviour change. Additionally, the application allows the user to rehearse responses towards different types of foods, which is accomplished by associating healthy foods with positive words and unhealthy foods with negative words. The purpose of Persuasive Systems Design (PSD) model, the main design framework used in this thesis, is to design behaviour change support systems. Behaviour Change Support Systems (BCSSs) are systems that aim to change behaviour and attitude without the use of any unethical means. Implicit association test (IAT) is a tool in the field of social psychology that is used measure implicit attitudes towards different concepts. Gamification can be defined as the use of game elements and mechanics in non-game contexts. The development process started with an analysis done with PSD model. Following it, mock-ups and a prototype based on the PSD model analysis and the original version of the IAT were created. After that, gamification features were designed by using a gamification framework. The original IAT was a strong influence in determining what types of persuasive and gamification features would be present in the application. Design science research guidelines were utilized as a checklist throughout research. The artefact and its persuasiveness were evaluated with a perceived persuasiveness questionnaire. The results showed slightly positive responses on the constructs of Primary Task Support (support for carrying out primary task), Dialogue Support (feedback), Perceived Credibility and Design Aesthetics. Perceived Persuasiveness responses were slightly negative. The reward feature that included unlocking different food icons and their health information was especially well received. This thesis contributed a detailed description of the development process of a BCSS. During the development process it was shown that the PSD model and the gamification framework could be used together without conflicts to design an artefact. The research on the artefact’s effectiveness in causing behaviour change is left for further study.

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Dias, Cleverton Oliveira. « Teoria BCS com efeito Rashba ». Universidade Federal do Amazonas, 2015. http://tede.ufam.edu.br/handle/tede/4987.

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This dissertation presents systematically the traditional superconductors, taking into account its discovery, properties that characterize the theory describing and changes taking place in their thermodynamic properties when subject to spin-orbit interaction Rashba. In the rst part are the key topics discussed related to phenomenon of superconductivity. It begins with a chapter 1 approach of the historical evolution of superconductivity and presentation properties that characterize a conventional superconductor, in addition to de ne superconductors Type I (conventional) and type II. The Chapter 2 is intended for an explanation of the microscopic BCS theory whose application is associated with type I superconductors, although this chapter argue about the interaction of electrons with the network, thus forming what is called Cooper pairs. The Chapter 3 is intended to introduce the Rashba model, which can be veri ed in two ways: by spontaneous generation of electric eld the junction interface of two materials or because application of the an external electric eld. In work not take into account the so that will be produced this electric eld. In Chapter 4 it shows the model Hamiltonian that constitutes the junction BCS Hamiltonian with the Hamiltonian of Rashba, from this model it is intended to calculate the e ect of Rashba interaction on the gap energy using the method of canonical transformations, consisting to assess the evolution of the operator concerned by a equation of dynamic evolution, allowing us nd the self energy carriers and their respective eigenvalues and associates them to gaps of energy. As a result of Chapter 4, Chapter 5 determine the gap superconductor function of temperature and the parameter R Rashba and as the thermodynamic properties of the model studied in this chapter also opens a space for comments and discussions. We end with Chapter 6, presenting partial conclusions, Related analytical curve made from certain data numerical, these curves will analyze the variation in thermodynamic properties of superconductors because the e ect Rashba.
A presente dissertação consiste em apresentar de forma sistemática os supercondutores tradicionais, levando em consideração sua descoberta, as propriedades que o caracterizam, a teoria que os descrevem e as mudanças que ocorrem em suas propriedades termodinâmicas quando submetidos a interação spin- orbita de Rashba. Na primeira parte são discutidos os t ópicos fundamentais referentes ao fenômeno da supercondutividade. Inicia-se o capítulo 1 com uma abordagem da evolução hist orica da supercondutividade e a apresentação das propriedades que caracterizam um supercondutor convencional, al em de de nir supercondutores tipo I (convencionais) e tipo II. O cap tulo 2 destina-se a uma explana c~ao da teoria microscópica BCS, cuja aplicação está associada a supercondutores de tipo I, ainda neste capítulo argumenta-se sobre a interação dos elétrons com a rede, formando assim o que chamamos de pares de Cooper. O capiítulo 3 destina-se a apresentar o modelo de Rashba, que pode ser verificado de duas maneiras: por geração espontânea de campo elétrico na interface da junção de dois materiais ou em razão da aplicação de um campo elétrico externo. No trabalho não se levar a em conta a maneira que ser a produzido esse campo elétrico. No capítulo 4 apresenta-se o Hamiltoniano do modelo, que consiste na junção do Hamiltoniano BCS com o Hamiltoniano de Rashba, a partir deste modelo pretende-se calcular o efeito da intera ção de Rashba, sobre os gaps de energia utilizando o m etodo das transforma ções canônicas, que consiste em avaliar a evolu ção temporal do operador em questão por meio de uma equa ção de evolução dinâmica, o que nos permitir a encontrar os autovetores de energia e seus respectivos autovalores e associa-los aos gaps de energia. Como consequência do capítulo 4, no cap tulo 5 determinaremos o gap do supercondutor em fun ção da temperatura e do parâmetro de Rashba R, bem como as propriedades termodinâmicas do modelo estudado, neste cap tulo tamb em abre-se um espa co para comentarios e discussões. Finalizamos com o cap tulo 6, apresentando conclusões parciais, relacionadas a an alise de algumas curvas feitas a partir de dados num ericos, estas curvas permitirão analisar a varia ção nas propriedades termodinâmicas dos supercondutores devido o efeito Rashba.

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Suhada, Robert. « The XMM-BCS galaxy cluster survey ». Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-132857.

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Cerrito, Stefano. « Thermodynamics of the BCS-BEC crossover ». kostenfrei, 2007. http://mediatum2.ub.tum.de/doc/623023/document.pdf.

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Bollmark, Gunnar. « Self-energy effects in BCS superconductors ». Thesis, KTH, Fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-238681.

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Ljepavic, Danijela. « Les expressions figées en français et en BCMS : traduction, comparaison ». Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAC013.

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Cette thèse procède à une comparaison des expressions figées entre les langues BCMS (bosniaque/bosnien, croate, monténégrin, serbe) et le français en vue de la traduction. Dans la première partie, l'étude commence par la définition des expressions figées et des critères de figement. Après avoir fait le point sur la question des langues BCMS, on présente le corpus des expressions figées en BCMS et en français, avec leur répartition dans différents domaines culturels et la distinction de trois types d'expressions : calques, expressions transparentes, expressions opaques. La seconde partie est consacrée à l'analyse comparative des expressions figées en BCMS et en français. Elle commence par un parcours de leurs différentes origines, puis on examine les fondements culturels des expressions figées, en fonction de différents domaines fournisseurs. On développe ensuite une analyse linguistique comparée des expressions figées, en détaillant les noms composés et les différentes locutions (verbales, adjectivales etc.) et en intégrant la dimension rhétorique, notamment les métaphores. Pour finir, après une mise au point générale sur la traduction, on examine les problèmes d'interprétation et les différentes solutions de traduction des expressions figées dans les deux sens, entre français et BCMS
This thesis makes a comparison between the idioms of the BCMS languages (Bosnian, Croatian, Montenegrin, Serbian) on the one side, and the French language on the other, in the domain of translation.In the first segment, the study begins with the definition of idioms and the criteria for fixation. After the explanation of differences among BCMS languages, we present the corpus of idioms in BCMS and in French, with their distribution within different cultural domains, while distinguishing among three types of idiomatic expressions: literal, transparent, and opaque.The second part is devoted to the comparative analysis of idioms in BCMS and French. It begins with a record of their different origins, after which we examine the cultural foundations of expressions, depending on different domains. We develop a comparative linguistic analysis of idioms, giving details on various compound names and phrases (verbal, adjectival, etc.), and integrating the rhetorical dimension, including metaphors. Finally, after an overall focus on translating, we examine issues found in interpretation and translation solutions for different idioms between French and BCMS

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Fonseca, Vinicius Borges. « Plano de marketing para a BCS Shop ». Master's thesis, Instituto Superior de Economia e Gestão, 2019. http://hdl.handle.net/10400.5/19557.

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Mestrado em Marketing
O presente projeto tem como objetivo a elaboração de um plano de marketing para a empresa BCS Shop, que atua no sector de retalho de artigos desportivos e vestuário na Europa, nomeadamente no mercado de surf e moda praia. A empresa é jovem, possui uma gestão não profissionalizada e apresenta dificuldades na articulação dos múltiplos canais de venda e dos pontos de contacto com o cliente. O estudo realizado é de natureza exploratória. Com o objetivo de obter informação acerca da situação atual da empresa foram utilizados dados quantitativos secundários e realizada uma entrevista semiestruturada com o CEO. Já para obter informações acerca da qualidade do serviço e da integração e consistência dos pontos de contacto do cliente com a organização, foram realizadas entrevistas semiestruturadas. A estratégia adotada foi a de action research. A realização do diagnóstico da empresa foi essencial para a melhor compreensão da sua envolvente operacional e estratégica. Dos resultados obtidos foi possível propor um plano de marketing para a empresa onde foi dada especial atenção à optimização dos canais de venda e integração dos pontos de contacto com o cliente tanto na loja física quanto na virtual. Os resultados encontrados auxiliaram o desenvolvimento de estratégias e táticas em um plano de marketing coerente e consistente com os objetivos da empresa.
This project aims to develop a marketing plan for BCS Shop, which operates in the sporting goods and clothing retail sector in Europe, especially in the surf and beachwear market. The company is young, and has a non-professionalized management, therefore difficulties in articulating sales channels and touch points with customers. The study is exploratory in nature. In order to obtain information about the current situation of the company, secondary quantitative data were used and a semi-structured interview with the CEO was conducted. To evaluate and obtain information about the quality of service and the integration and consistency of customer contact points with the organization, semi-structured interviews were conducted. The strategy adopted was action research. Conducting the company's diagnosis was essential for a better understanding of its operational and strategic areas. From the results it was possible to build a maketing plan for the company with a special attention in optimizing sales channels and integrates customer touch points in both the physical store and the online store. The results found supported the development of strategies and tactics in a marketing plan consistent with the company's objectives.
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Santos, Edgar Gonzaga Souza dos. « Supercondutividade BCS na rede tabuleiro de xadrez ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/12171.

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Tendo por motivação as propriedades supercondutoras do óxido metálico Cd2Re207, cuja estrutura cristalina é do tipo pirocloro, propomos um modelo eletrônico em uma rede do tipo tabuleiro de .1:adrez,que pode ser vista como um análogo bidimensional da rede piroclórica. Incluindo somente graus de liberdade de carga, tratamos o modelo através de uma aproximação BCS, realizando o desacoplamento dos termos de interação no espaço real. A passagem ao espaço recíproco dá origem a um modelo BCS de duas bandas acopladas, sendo uma delas não dispersiva. Nosso estudo da fase supercondutora se baseia na minimização numérica da energia livre. Propriedades características, como o quociente entre o parâmetro de ordem e a temperatura crítica ou o salto do calor específico na transição de fase, são obtidas e comparadas com os valores universais previstos pela teoria BCS para um sistema de uma única banda no limite de acoplamento fraco. Também discutimos as propriedades de simetria do gap supercondutor no espaço de vetores de onda.
Motivated by the superconducting properties of the metallic oxide Cd2Re207, whose crystal structure is of the pyrochlore type, we propose an electronic modeI on a checkerboard lattice, which can be viewed as a two-dimensional analog of the pyrochlore lattice. lncluding only charge degrees of freedom, we treat the modeI via a BCS approximation, decoupling the interaction terms in real space. Going over to reciprocal space yields a BCS modeI with two coupled bands, one of them being non-dispersive. Our study of the superconducting phase is based on numerical minimization of the free energy. Characteristic properties, like the ratio between order parameter and critical temperature or the specific-heat jump at the phase transition, are obtained and compared with universal values predicted by the BCS theory for a single-band system in the weak-coupling limito We also discuss the symmetry properties of the superconducting gap in wave-vector space.

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Diniz, Ricardo. « Modelo de bósons interagentes e sua relação com o BCS ». Universidade de São Paulo, 1990. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-30042014-152410/.

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Através de um hamiltoniano efetivo baseado no tratamento de NAMBU POT.90 para o BCS, no qual incluímos além do emparelhamento monopolar o emparelhamento quadrupolar, discutimos a relação entre esse modelo e o modelo de bósons interagentes. Uma aplicação e feita a cadeia o (6) do IBM, que corresponde ao limite GAMA-instável do modelo de bohr. As dificuldades encontradas e uma possível generalização para o modelo são discutidas.
The nambu mechanism for BCS theory is extended with inclusion of quadrupole pairing in adition to the usual monopole pairing. An effective Hamiltonian is constructed and its relation to the IBM is discussed. We discussed the faced difficulties and a possible generalization of the model.

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Négréa, Daniel. « Proton-neutron pairing correlations in atomic nuclei ». Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00870588.

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The common understanding of proton-neutron pairing, whose fingerprints are currently investigated in N = Z nuclei, relies on Cooper pair mechanism and BCS-type models. In the present thesis we present an alternative approach which, contrary to BCS models, conserves exactly the particle number and the isospin. In this approach the ground state of N=Z nuclei is described as a condensate of alpha-like quartets built by two neutrons and two protons coupled to the total isospin T=0 and total spin J=0. The comparison with exact shell model calculations shows that the quartet condensation model (QCM) gives a very accurate description of pairing correlations in N=Z nuclei, much better than the BCS models. It is also shown that proton-neutron pairing and alpha-type condensation are important not only for N=Z nuclei but also for nuclei with excess neutrons. In the latter case the condensate of alpha-like quartets coexist with the condensate of the neutron pairs in excess relative to the N=Z isotope. Using the framework of QCM we have also studied the competition between the isovector and the isoscalar proton-neutron pairing in nuclei with N=Z. Our results indicate that the contribution of isoscalar pairing to the ground state pairing correlations is very small compared to the isovector pairing.

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Ghosh, Angsula [UNESP]. « Modelo BCS renormalizado e supercondutores de alta temperatura ». Universidade Estadual Paulista (UNESP), 1999. http://hdl.handle.net/11449/132796.

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Ghosh, Angsula. « Modelo BCS renormalizado e supercondutores de alta temperatura / ». São Paulo : [s.n.], 1999. http://hdl.handle.net/11449/132796.

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Kubbinga, Marlies [Verfasser]. « BCS-based biowaivers : risks and opportunities / Marlies Kubbinga ». Mainz : Universitätsbibliothek Mainz, 2017. http://d-nb.info/1122753373/34.

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Kubbinga, Marlies [Verfasser]. « BCS-based biowaivers : risks and opportunities / Marlies Kubbinga ». Mainz : Universitätsbibliothek Mainz, 2016. http://d-nb.info/1120742323/34.

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Woldemicael, B. (Bereket). « Designing a BCSS for mobile devices:an application to help the chronically tardy ». Master's thesis, University of Oulu, 2015. http://urn.fi/URN:NBN:fi:oulu-201511212162.

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The purpose of this thesis is to study the process of developing a behaviour change support system (BCSS) which help users to manage and utilize their time. Proper time management is an important asset for a successful life. However, most of us have difficulties in using our time efficiently due to various reasons. Some of the reasons include procrastination and becoming overoptimistic about completing tasks in short periods of time. On this study, an iOS based application is developed based on BCSS theory. The application can be used by anyone who wants to improve their efficiency in time management. The intention of the system is to help users identify and improve their weaknesses on time management through using the application for a longer period. BCSS is one area of persuasive technology research, and it is defined as information systems designed to form, alter or reinforce attitudes, behaviours or an act of complying without using deception, coercion or inducements. BCSS are applied in various sectors such as health, wellness and environment. It is also important to note that Persuasive System Design model (PSD) is used as the main construct to develop our system. PSD provides a recent and technology oriented persuasion framework that helps to design, develop and evaluate BCSS. This project is based on a Design Science research method through developing an artefact. In the end, the system is evaluated qualitatively.

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Mapstone, Sally. « The advice to princes tradition in Scottish literature, 1450-1500 ». Thesis, University of Oxford, 1986. http://ora.ox.ac.uk/objects/uuid:a93e3e2d-89ce-4d4a-bcbf-47aa24f93e5c.

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The regions of James II, III, and IV in the second half of the fifteenth century in Scotland saw a distinctive flowering of advice to princes literature. This is the first account of its kind to examine in detail the sources, arguments, and extent of political comment of each individual work. In particular it employs both literary and historical sources to reveal the largely unrecognized impact of continental, especially French, political thought, on a number of writers. The study opens with a consideration of the poem De Regimine Principum, a politically very forthright advice work, influential for a century or so after its composition. Chapter 2 deals with the writings of Sir Gilbert Hay, whose work shows clear influences from the continent, particularly in the Buik of King Alexander, which is also seen to have interesting links with De Regimine Principum. Chapter 3 discusses the romance Lancelot of the Laik, a poem less precise in its allusions, but clearly indicative of a number of recurrent preoccupations in Scottish advisory literature in the areas of justice and kingly minorities. The two following chapters examine The Talis of the Fyve Bestes, which gives a markedly nationalistic evocation of good kingship, and The Buke of the Chess, where Scottish advice to princes is seen at its least politically aware. In Chapter 6 advice appears in yet another genre, the devotional poem The Contemplacioun of Synnaris, where the wider associations of `kingship' with the nosce te ipsum tradition are apparent. Chapters 7 and 8 concern The Thre Prestis of Peblis and John Ireland's Meroure of Wyssdome, possibly produced around the same time, but presenting their advice in very different manners: the Thre Prestis adroitly worked and entertaining, the Meroure, highly theological and drawing strongly on continental writers, notably the sermons of Jean Gerson. In conclusion it is shown that through this context we can best appreciate the purpose and formidable execution of Robert Henryson's advice to princes fable lq The Lion and the Mouse.

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Lim, Sean Wei Xinq. « Bayesian inverse problems and seismic inversion ». Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:ed60b058-3957-4414-bcb2-db6b5b3c0593.

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The Bayesian formulation for inverse problems gives a way of making inferences about unknown quantities not directly observable. The application of Bayes' Theorem combines the prior information and the observation to give a posterior measure, which contains information about the quantity we are trying to estimate. In this thesis, we review a particular formulation, conventionally known as the strong constraint formulation of inverse problems. We describe methods to obtain summaries of information from the posterior measure. We also describe how prior measures are constructed using linear differential operators, to quantify as accurately as possible our knowledge of the parameters, independent of any observations. Then, we note that the strong constraint formulation of inverse problems makes it hard to obtain summaries of information of the posterior measure, typically obtained through an optimization of a misfit functional. Therefore, we introduce the weak constraint formulation in a Bayesian context for inverse problems, which eases the task of optimization. We use this formulation to perform sampling of the posterior measure. This method is tested on some simple test problems. We also compare the results between a strong and weak constraint formulation of inverse problems by studying a one-dimensional example. Finally, we apply the weak constraint formulation to the problem of full waveform inversion, which is a common problem in seismology. The forward problem we use here is the Laplace transform of the acoustic wave equation, and the inverse problem is solved in several frequencies. There are two approaches when observations at several frequencies are available. First is the sequential method, which processes the observation at different frequencies individually. The second method, which is the simultaneous method, processes the observations at all frequencies at once. We use the simultaneous method here, and used a non-trivial model problem, which yields promising results.

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Bowen, Robert. « The internationalisation of food and drink SMEs : towards a recipe for success ». Thesis, Aberystwyth University, 2017. http://hdl.handle.net/2160/001d31b7-cdf7-42fd-bcb0-4e87223b5250.

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This research provides an investigation of the critical success factors of SMEinternationalisation within the food and drink industry. Since the seminal works of the Uppsala scholars (Johanson & Wiedersheim-Paul, 1975; Johanson & Vahlne, 1977), SME internationalisation has developed as a field in recent decades with numerous studies investigating different theories across a range of industries and locations. The purpose of this study is to contribute to research in this field by investigating specific issues for food and drink SMEs, as there is an increasing need to focus research on specific research contexts (Fillis, 2008). Considering the close associations that exist between food and place (Tregear, 2001), the role of place is incorporated with traditional theories of SME internationalisation in a conceptual framework designed to reflect the critical success factors of food and drink SME internationalisation. A mixed methods study, both quantitative and qualitative methods were used to gather and analyse data from food and drink producers in two independent phases. Wales and Brittany were chosen as case studies for this study, with both regions sharing cultural and geographical characteristics as regions where the food and drink industry is a prominent part of the economy. Findings of the study highlight that most companies, regardless of size and location, have the ability to internationalise, provided that the conditions for internationalisation are supportive for companies that wish to do so. The study identifies 4 company types that describe companies in relation to their international activities, ranging from improbable exporters to proactive exporters. Findings of the study culminate in the creation of two models, which outline the conditions required for internationalisation and the process in which a company can develop international activities through awareness and networks.

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Remmelzwaal, Serginio. « Assessing past oxygen in the ocean using Cr isotopes as a palaeo-proxy ». Thesis, University of Bristol, 2018. http://hdl.handle.net/1983/d38b75bf-f8bb-4671-bcbb-f3d71629b900.

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As greenhouse gas emissions into the atmosphere persist, both oceanic and atmospheric temperatures are projected to continue rising with major consequences for the marine environment. One of the major environmental hazards of this century is the spread of low-oxygen environments or ocean deoxygenation. While modern hypoxic environments are closely monitored, the mechanisms leading to these conditions are not fully understood in the context of an Earth system. Past ocean deoxygenation can be used as an analogue to shed light on oceanic dissolved oxygen responses to global warming. The aim of this study is to ground truth the palaeo-redox proxy of the Cr isotopic composition of foraminifera and bulk carbonates to elucidate the processes that led to and the eventual extent of hypoxic and anoxic environments during past climatic events. The potential of foraminiferal Cr isotopes as a new redox proxy was assessed by determining element partitioning and isotopic fractionation of Cr by foraminifera using a variety of geochemical techniques (LA-MC-ICP-MS, (MC-)ICP-MS, nanoSIMS). To date, Cr isotopes in biogenic carbonates have been interpreted to record the seawater δ53Cr composition at the site of test mineralisation in the surface ocean. While Cr is distributed throughout the foraminiferal test in both fossil and modern samples, sediment (fossil) core-top samples have up to two orders of magnitude more Cr than non-sedimentary and culture samples. This study concludes that Cr in foraminifera is mostly post-depositional and records bottom/pore water signals. Chromium isotopes in carbonates were applied to study how climate change influenced ocean deoxygenation during the Pleistocene, Palaeocene-Eocene Thermal Maximum, Eocene Thermal Maximum 2, Ocean Anoxic Event 2 and Ocean Anoxic Event 1a. Chromium isotopes in carbonates record local seawater deoxygenation during these events. Open ocean deoxygenation can mainly be pinned to rising temperatures in intermediate ocean waters.

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Palin, Richard Mark. « Using metamorphic modelling techniques to investigate the thermal and structural evolution of the Himalayan-Karakoram-Tibetan orogen ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:f86580ad-c183-4ecd-bcbd-17f3a1b74548.

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Metamorphic rocks constitute a vast volumetric proportion of the Earth’s continental lithosphere and are invaluable recorders of the mechanisms and rates of deformation and metamorphism that occur at the micro-, meso- and macro-scale. As such, they have the potential to provide detailed insight into important tectonic processes such as the subductive transport of material into, and back from, mantle depths and also folding, faulting and thickening of crust that occurs during collisional orogeny. The Himalayan-Karakoram-Tibetan orogen is the youngest and most prominent example of a continent-continent collisional mountain belt on Earth today and is a product of the on-going convergence of the Indian and Asian plates that initiated in the Early Eocene. Thus, it provides an exceptional natural laboratory for the investigation of such processes. Recent advances in the computational ability to replicate natural mineral assemblages through a variety of metamorphic modelling techniques have led to improvements in the amount (and quality) of petrographic data that may be obtained from a typical metamorphic rock. In this study, phase equilibria modelling (pseudosection construction) using THERMOCALC, amongst other techniques, has been integrated with in-situ U–Pb and Th–Pb geochronology of accessory monazite in order to constrain the tectonothermal evolution of four regions intimately associated with the Himalayan-Karakoram-Tibetan orogen. These regions comprise the Karakoram metamorphic complex (north Pakistan), the Tso Morari massif (north-west India), the eastern Himalayan syntaxis (south-east Tibet) and the Day Nui Con Voi metamorphic core complex of the Red River shear zone (North Vietnam). Each case study documents previously unreported metamorphic, magmatic or deformational events that are associated with the India-Asia collision. These data have allowed original interpretations to be made regarding the tectonic evolution of each individual region as well as the large-scale evolution of the Himalayan-Karakoram-Tibetan orogenic system as a whole.

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Griffiths, Helen Caroline. « Defining and explaining positive psychological outcomes in people with physical health conditions ». Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:d538f2ec-d40f-4701-bcbb-f908a409380d.

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Experiencing a physical health condition can have wide ranging physical and psychological outcomes for an individual, impacting on many aspects of daily living. The psychological outcomes can vary widely, from extreme psychological distress to psychological growth, and are complex and dynamic. Traditionally, research has focused on those experiencing psychological distress, despite evidence showing that many individuals are able to achieve positive psychological outcomes. The literature is unclear in defining different positive psychological outcomes, and indeed distinguishing different outcomes and processes from one another. Attention needs to be paid to the definition applied to individuals who are reporting positive psychological outcomes following physical health difficulties and further understanding the process through which individuals achieve these outcomes. This empirical study aimed to address some of the gaps in the literature, by exploring how six individuals reporting positive psychological outcomes following spinal cord injury described and explained these outcomes. Interpretative phenomenological analysis was used to investigate the experience of these individuals. Three superordinate themes were extracted: "Living a normal life, just doing things differently", "Overcoming challenges: Determination to succeed" and "Using the resources available to me". The research supported the idea that positive psychological outcomes arise through a complex interplay between personality, cognitive and environmental factors. Theoretically, this research has implications for defining positive psychological outcomes following spinal cord injury, in addition to contributing towards future theoretical frameworks that aim to provide a basis for understanding the process through which positive psychological outcomes following spinal cord injury are achieved. Clinically, this research provides a narrative that can be used with people following spinal cord injury and also provides evidence for the use of cognitive screening measures such as appraisal style, to identify individuals who may be showing less adaptive cognitions.

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Neagu, Mariela. « Young adults' perspectives on their experiences of different types of placement in Romania ». Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:d1fe5a7a-bcbb-4482-b9f1-298904bf776d.

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This study explores the childhood experiences and transitions to adulthood of 39 Romanian care leavers and adoptees, born around 1989 - 1990. In the past, Romania's children in care became known to the world as 'the Romanian orphans' and some of them have been subjects to neurodevelopmental research studies focusing on the setbacks posed by institutionalisation in early life. This research project takes a different angle by: • Using life history approach and therefore capturing the participants' in-depth accounts of how they recall their childhoods and the challenges they encountered in their transition to independent life; • Exploring four different types of placements and how they affect transition to independent life, from a user's perspective. The fact that Romania undertook reform of the child protection system within the timespan of this generation of children provided a research opportunity to collect the users' views on different types of placement that belonged to the unreformed system of the 1990s (large residential care and intercountry adoption) and the new types of placement (small group homes and foster care). For comparison purposes, I also included domestic adoption, a type of placement that was less controversial than the others at the time reforms were being introduced. Thus, the types of placement that are analysed through the research participants' accounts are: • Residential care (institutions and small group homes); • Foster Care; • Domestic Adoption; • Intercountry adoption. The study addressed two research questions: 1. How do Romanian born young people who grew up in care understand and narrate their experiences in different types of placement? 2. What narratives of agency are constructed by Romanian-born adults who grew up in different types of placement when they describe their transition to adulthood? By taking an interpretive stance, this study brings in the academic arena the voices of care leavers and adoptees. By using narrative analysis and focussing on the concept of dignity by employing identity theories, the UN Convention on the Rights of the Child and the Capabilities Approach, the study makes an important contribution to knowledge, with implications for further research, policy and practice. While interventions in child protection are influenced in each country by cultural, political and socio-legal factors, understanding the basic needs of children who are not raised by their birth families is important across different child protection systems. Therefore, the relevance of the research findings is not limited to Romania.

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Macdonald, Robert Duncan. « The cervix in pregnancy : an ultrasonographic investigation of the cervix and cervical change through pregnancy ». Thesis, University of Bristol, 2000. http://hdl.handle.net/1983/cdf0c3f4-5f40-4465-bcbc-a2cabdfa6d33.

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Hamann, Fábio André. « Aspectos do controle biológico de Botrytis cinerea Pers. Ex. Fr. em videira ». Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/5054.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Rio Grande do Sul (RS), the most important state of grape production in Brazil, harvests, approximately, 780 thousand tons annually. One of the biggest constraint factors to the obtainment of higher production numbers is the incidence of late season diseases in vineyards, being botrytis bunch rot, caused by Botrytis cinerea, one of the major contributors for field and post-harvest losses. Red grapes can show more resistance against this fungus, due to higher levels of phenolic compounds. The use of biological control agents (BCAs) emerges as a promising alternative to control botrytis disease. For this reason, the objectives of this study were to test isolates from this fungal pathogen, originated from the two main grape production regions in the state of RS, trough in vitro direct confront test against BCAs fungal isolates (Trichoderma spp. and Gliocladium sp.) and to test the same pathogen isolates on semi in vivo biological control, against the BCAs isolates which obtained the highest biological activity during the in vitro test, on the post-harvest storage of table grapes, on a red and a white cultivar. The B. cinerea isolates used were UFSM SG01, UFSM SG02, from serra (mountain range) region, UFSM CM01, and UFSM CM02, from campanha meridional (meridional pampas) region. The BCAs isolates used in this study were Tricoderma spp., UFSM T20, UFSM T17, UFSM T15.1 (obtained from soil), UFSM TSG, UFSM TCM (obtained from the same grape bunches where B. cinerea was isolated, representing each region), and Gliocladium sp., UFSM G4DB (obtained from soil). UFSM TSG, UFSM TCM and UFSM T15.1 showed the highest biocontrol activity (B. A.) in vitro, in general over 50% against all B. cinerea isolates. The same BCAs were selected to be used at the semi in vivo test with detached berries for three inoculation periods: B+T, pathogen and BCA inoculated at the same time; B+24hT, pathogen inoculated first and BCA 24 h later, T+24hB, BCA inoculated first and pathogen 24 h later. A higher control, considered as the lower damage level, on T+24hB period, showed the importance of preventive treatment. Cracks on berries played a more important role than the color of the skin for botrytis infection.
O Rio Grande do Sul, o estado produtor de uvas mais importante no Brasil, colhe em média 780 mil toneladas por ano. Um dos maiores entraves para a obtenção de maiores médias de produção é a incidência de doenças de final de ciclo (DFC), sendo Botrytis cinerea, agente causador da podridão-cinzenta, um dos maiores responsáveis por perdas de produção no campo e na pós-colheita. Uvas tintas podem apresentar maior resistência à podridão-cinzenta, devido à maior concentração de compostos fenólicos. O uso de agentes de controle biológico (BCAs) é uma alternativa promissora no controle da podridão de botrytis. Dessa maneira, os objetivos deste estudo foram testar isolados do patógeno coletados das duas principais regiões vitivinícolas do RS em confronto direto in vitro com isolados de agentes antagonistas (Trichoderma spp e Gliocladium sp.) e testar os mesmos isolados do patógeno em controle biológico semi in vivo com os isolados antagonistas que obtiveram as maiores médias de atividade de biocontrole no teste in vitro, na pós-colheita de uvas de mesa, em cultivares branca e tinta. Os isolados de B. cinerea empregados foram UFSM SG01, UFSM SG02, UFSM SG 03, oriundos da serra, e UFSM CM01 e UFSM CM02, oriundos da campanha meridional. Os isolados antagonistas empregados no teste in vitro foram UFSM T20, UFSM T17, UFSM T15.1 (oriundos de solo), UFSM TSG, UFSM TCM (oriundos de cachos de uva coletados nas mesmas regiões de coleta do patógeno), de Trichoderma spp., e UFSM G4DB, de Gliocladium sp.. Os isolados UFSM TSG, UFSM TCM e UFSM T15.1 foram os três que obtiveram as maiores médias de atividade de biocontrole, em geral acima de 50%, para todos os isolados de B. cinerea, testados em confronto direto in vitro. Esses isolados BCAs foram selecionados para o teste de controle biológico semi in vivo em bagas destacadas, em três períodos de inoculação: B+T, antagonista e patógeno aplicados ao mesmo tempo; B+24hT, patógeno inoculado primeiro e antagonista 24h após, T+24hB, antagonista aplicado primeiro e patógeno 24h após. O maior controle, assumido a partir do menor grau de dano, no período T+24hB, evidenciou a importância do tratamento preventivo. Rachaduras em bagas tiveram maior influência do que a coloração da casca na ocorrência da podridãocinzenta.

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Casadei, Matteo. « Analisi critica della superconduttività BCS in relazione all'effetto Meissner ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16781/.

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In questa tesi vengono analizzati i principali argomenti con cui il fisico argentino J.E. Hirsch critica la descrizione dell' effetto Meissner nella teoria della superconduttività BCS. Hirsch afferma che la spiegazione dell' effetto Meissner nel framework tradizionale sia incompatibile con la conservazione del momento angolare e con la reversibilità della transizione superconduttiva, e propone una teoria alternativa, chiamata hole superconductivity, che sarebbe in grado di fornire una descrizione soddisfacente di questi fenomeni. Nel primo capitolo sono riportati i principali risultati ottenuti dalla teoria BCS. Nel secondo capitolo si espongono le argomentazioni critiche mosse da Hirsch. In particolare, quando la transizione superconduttiva avviene in presenza di un campo magnetico costante, Hirsch sostiene che la teoria BCS non contenga al suo interno gli elementi fisici in grado di generare la corrente di Meissner che scherma il campo, e di giustificare la reversibilità della transizione. Nel terzo capitolo viene proposto il meccanismo della hole superconductivity che, secondo Hirsch, è in grado di spiegare in modo consistente tali fenomeni. Vengono affrontati solo gli aspetti della hole superconductivity inerenti alla critica mossa da Hirsch, non viene trattata la teoria nella sua interezza.

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Dobrek, Łukasz. « Optical manipulation of ultra cold gases and dipolar BCS ». [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970679203.

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Liao, Renyuan. « Fermion Pairing and BEC-BCS Crossover in Novel Systems ». Kent State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883.

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Geaney, Jacqueline N. « The Attitude-Behavior Disconnect : Identifying factors that moderate behavior in BC's environmental movement ». Thesis, Boston College, 2010. http://hdl.handle.net/2345/1320.

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Thesis advisor: Brian Gareau
This study examines how attitudes of environmental concern affect the behavior of students on the Boston College (BC) campus. Conventional wisdom suggests that attitude would determine behavior, but past studies have been unable to find a connection between environmental attitude and behavior. This suggests that there are other factors at play, in addition to environmental concern. Using survey and in-depth interview data, this study focuses on the influence of the following factors: monetary cost, convenience, habit and visibility of consequences. The findings suggest that attitude itself does influence environmental behavior, but that the aforementioned factors play an important role in either increasing or decreasing the rate of behavior. I conclude by suggesting that the impact of cost as a barrier to behavior speaks to the importance of structural change in order to increase the rate of green behavior
Thesis (BA) — Boston College, 2010
Submitted to: Boston College. College of Arts and Sciences
Discipline: Sociology Honors Program
Discipline: Sociology

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Eneias, Ronivon Louren?o. « Pareamento BCS em um L?quido de Luttinger em 1D ». Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16575.

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Made available in DSpace on 2014-12-17T15:14:53Z (GMT). No. of bitstreams: 1 RonivonLE_DISSERT.pdf: 2244591 bytes, checksum: e86660db1b3ec37036777503cc5e8a0d (MD5) Previous issue date: 2010-12-20
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
In this work we investigate the effect of a BCS-type pairing term for free spinless fermions, with a propensity to form a condensate of pairs in a 1+1 dimension. Using the of bosonization technique we explore the possible condition of existence of quasiparticles in a superconducting state. Although there is no spontaneous breaking of chiral symmetry the propagator of one-particle fermion is massive and, in fact, resembles the one-particle Green s function of conventional quasiparticles
Neste trabalho investigamos o efeito de um termo de emparelhamento do tipo BCS para f?rmions livres sem spins, com propens?o a formar um condensado de pares em uma dimens?o 1+1. Utilizando a t?cnica de bosoniza??o vamos explorar a poss?vel condi??o de exist?ncia de quasipart?culas em um estado supercondutor. Embora n?o haja nenhuma quebra espont?nea de simetria quiral o propagador de 1-part?cula fermi?nica ? massivo e de fato assemelha-se a fun??o de Green de 1-part?cula de uma quasipart?cula convencional

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Ciavatta, Alessandro. « Teoria della superconduttività e soluzione numerica dell’equazione della gap BCS ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23633/.

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La superconduttività è uno stato della materia caratterizzato dall'assenza di resistività DC. Durante la transizione di fase il materiale espelle dall'interno il campo magnetico applicato, diventando un perfetto diamagnete; questo è noto come effetto Meissner-Ochsenfeld. La prima teoria presentata in questa tesi è la teoria di London, che spiega l'effetto Meissner all'interno delle due equazioni fenomenologiche di London. In seguito viene presentata la teoria di Ginzburg-Landau, che estende la teoria di Landau sulle transizioni di fase del secondo ordine e ricava una dipendenza della densità dei portatori superconduttivi dai parametri termodinamici. Infine viene descritta la teoria microscopica BCS (Bardeen-Cooper-Schrieffer), che supponendo l'interazione elettrone-elettrone attrattiva riesce a dimostrare l'esistenza di un gap energetico, fornendo una spiegazione microscopica alle teorie fenomenologiche. L'equazione che esplicita la dipendenza dell'energia di gap dalla temperatura è stata risolta numericamente tramite un codice in Python.

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Souza, Leonardo da Fonseca. « Controle avançado aplicado ao sistema bcs operando com escoamento monofásico ». Escola Politécnica /Instituto de Matemática, 2014. http://repositorio.ufba.br/ri/handle/ri/23032.

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Existem diversas técnicas de elevação artificial de petróleo. Este trabalho trata especificamente o método do Bombeio Centrífugo Submerso (BCS). Este método possui a vantagem de elevar altas vazões de fluidos em relação às demais técnicas de elevação, além de poder atuar sob diferentes condições dinâmicas de escoamento. O presente trabalho tem como objetivo o uso da técnica de controle Supervisor Fuzzy-PID e Adaptativo para levar o bombeio centrífugo submerso a operar no head desejado, mesmo na presença de incertezas e dinâmicas não modeladas. O Laboratório de Elevação Artificial (LEA), da Escola Politécnica da Universidade Federal da Bahia, dispõe de uma planta BCS com um poço de 32mde altura completamente instrumentado, num ambiente experimental que favorece o desenvolvimento de estudos e pesquisas, entre outros, na área de controle. Para o presente estudo foram realizados experimentos práticos que possibilitaram o desenvolvimento de modelos a partir de dados medidos. Além disso, os resultados obtidos com o método de controle Supervisor Fuzzy-PID e Adaptativo em ambiente simulado mostram que há estabilidade no sinal de controle e na resposta da planta. Assim espera-se contribuir na formulação de novas estratégias de controle aplicáveis ao método de bombeio centrífugo submerso.

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Silva, Wesley Gomes da. « Banco de Cérebros do Brasil Central (BCBC) : prevalência de demências e correlação clínico-patológica ». Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/5794.

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The diagnosis of dementia is made through autopsy. The histopathological and immunohistochemical technique makes it possible to differentiate the subtypes of dementia by pre-established macroscopic and microscopic criteria. Banks brain, although recent, provide biological material quality for multidisciplinary research in normal subjects and with dementia. Objectives: To correlate clinical findings with neuropathological cases with dementia from the Brains Bank of Central of Brazil (BBCB); establish morphological patterns in macroscopic focal dementias; determine the prevalence of diagnosis of other types of dementia. Materials and Methods: Brain Study from autopsies of patients with neurodegenerative diseases of dementia clinic of the HC-UFG (Ethics Committee of the Protocol on research 0692007). The brains were processed following dissection and measurement protocol. Appropriate external and macroscopic morphological descriptions and coronal and sagittal sections were performed. Results: 15 brains, 9 female patients were studied, aged 10 to 89 years. The types of dementias found in BCBC were 5 cases of frontotemporal dementia (FTD), 3 Alzheimer's disease (AD), 3 patients had primary progressive aphasia (PPA) and corticobasal degeneration (CBD), 1 Huntington's disease, 1 disease Creutzfeldt-Jakob 1, Rasmussen's encephalitis and 1 depressive pseudodementia (Cotard’s syndrome). Described frontal gyrus supernumerary in 3 cases of CBD and 2 cases of FTD. Discussion: Most cases presented morphological pattern of the respective type of dementia according to the literature, except PPA with CBD. In BCBC material only 20% of AD cases were 27% and frontotemporal lobar degeneration (FTLD). Conclusion: The higher prevalence of dementia in BCBC was the type FTLD. The frontotemporal focal atrophy was the most observed type of change. The cases with FTD showed classic morphological patterns, while the PPA CBD was different standard literature. The BCBC will enable studies in various research areas.
O diagnóstico definitivo das demências é feito através de necropsia. Os exames anatomopatológico e imunoistoquímico possibilitam diferenciar os subtipos de demência por critérios macroscópicos e microscópicos pré-estabelecidos. Os bancos de cérebros, apesar de recentes, fornecem material biológico de qualidade para pesquisas multidisciplinares de indivíduos normais e com demência. Objetivos: Correlacionar aspectos clínicos com alterações neuropatológicas de casos com demências provenientes do Banco de Cérebros do Brasil Central (BCBC); estabelecer padrões morfológicos macroscópicos nas demências focais; verificar a prevalência do diagnóstico de outros tipos de demências. Materiais e Métodos: Estudo de cérebros provenientes de necropsias de pacientes com doenças neurodegenerativas do ambulatório de demências do HC-UFG (protocolo do Comitê de ética em pesquisa 0692007). Os cérebros foram processados seguindo protocolo de dissecção e mensuração. Foram realizadas as devidas descrições morfológicas e macroscópicas externas e dos cortes coronais e sagitais. Resultados: Foram estudados 15 cérebros, 9 de pacientes do sexo feminino, com idade entre 10 a 89 anos. Os tipos de demências encontrados no BCBC foram: 5 casos de demência frontotemporal (DFT), 3 de doença de Alzheimer (DA), 3 casos com afasia progressiva primaria (APP) e degeneração corticobasal (DCB), 1 de doença de Huntington, 1 de doença de Creutzfeldt-Jakob, 1 de encefalite de Rasmussen e 1 de pseudodemência depressiva (síndrome de Cotard). Foi observado giro frontal supranumerário nos 3 casos de DCB e em 2 casos de DFT. Discussão: A maioria dos casos apresentou padrão morfológico do respectivo tipo de demência de acordo com a literatura, exceto APP com DCB. No material do BCBC apenas 20% dos casos foram de DA e 27% degeneração lobar frontotemporal (DLFT). Conclusão: A maior prevalência de demências no BCBC foi do tipo DLFT. A atrofia focal frontotemporal foi o tipo de alteração mais observada. Os casos com DFT apresentaram padrões morfológicos clássicos, enquanto que os de APP com DCB apresentaram padrão diferente da literatura. O BCBC possibilitará a realização de estudos em várias linhas de pesquisa.

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Coleman, Shannon L. « Criterion validation of the Binghamton Childhood Abuse Screen (BCAS) using the modified Stroop procedure ». Diss., Online access via UMI:, 2008.

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MARTINS, J. R. « ANÁLISE NUMÉRICA DA DISSIPAÇÃO DE CALOR DO MOTOR ELÉTRICO DO SISTEMA BCSS EM SKID ». Universidade Federal do Espírito Santo, 2018. http://repositorio.ufes.br/handle/10/8453.

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O desenvolvimento recente do S-BCSS (Bombeio Centrífugo Submerso Submarino em Skid), assentado no leito marinho, é uma alternativa ao sistema convencional, facilitando intervenções em caso de falha. A bomba é acionada por um motor elétrico cujo resfriamento deve ser eficiente para garantir a continuidade do seu funcionamento. A retirada de calor do motor é efetuada pelo fluido produzido. O intuito desta dissertação é compreender o processo de resfriamento do motor elétrico para o escoamento monofásico, turbulento com transferência de calor por convecção em uma geometria anular, que representa o espaço formado entre a cápsula e o motor do sistema S-BCSS. Com este objetivo é utilizado a dinâmica de fluidos computacional (CFD Computational Fluid Dynamics) para resolver esse escoamento, o modelo de turbulência utilizado é o kappa-epsilon padrão com função de parede melhorada (Enhanced Wall Treatment). São consideradas quatro vazões de operação do sistema, três fluidos com diferentes números de Prandtl, três configurações de geometrias anulares diferentes, uma concêntrica e duas excêntricas, juntamente com a condição de temperatura na superfície do motor constante. As simulações são validadas através da comparação do número de Nusselt na região desenvolvida com a correlação de Gnielinski. Observa-se que a simulação desse escoamento possui dependência geométrica, sendo necessário a utilização de uma geometria 3D. Se a condição de fluxo de calor constante fosse utilizada, a temperatura do motor apresentaria menores intensidades no início e maiores no final da geometria. Portanto, quanto maior o número de Nusselt, maior é a transferência de calor, assim intensificando o resfriamento do motor elétrico. Na geometria excêntrica é observada uma transferência de quantidade de movimento da região anular inferior para a superior, fazendo com que o número de Nusselt apresente uma variação angular. Em geometrias excêntricas o escoamento se desenvolve em maiores comprimentos, observando que quanto maior a excentricidade, maior é este comprimento. Por fim, destaca-se que para o sistema S-BCSS a utilização de uma geometria excêntrica não é adequada. Palavras chave: S-BCSS, resfriamento do motor, excentricidade anular, número de Nusselt, CFD.

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Iskin, Menderes. « BCS to BEC Evolution and Quantum Phase Transitions in Superfluid Fermi Gases ». Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16326.

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This thesis focuses on the analysis of Bardeen-Cooper-Schrieffer (BCS) to Bose-Einstein condensation (BEC) evolution in ultracold superfluid Fermi gases when the interaction between atoms is varied. The tuning of attractive interactions permits the ground state of the system to evolve from a weak fermion attraction BCS limit of loosely bound and largely overlapping Cooper pairs to a strong fermion attraction limit of tightly bound small bosonic molecules which undergo BEC. This evolution is accompanied by anomalous behavior of many superfluid properties, and reveals several quantum phase transitions. This thesis has two parts: In the first part, I analyze zero and nonzero orbital angular momentum pairing effects, and show that a quantum phase transition occurs for nonzero angular momentum pairing, unlike the $s$-wave case where the BCS to BEC evolution is just a crossover. In the second part, I analyze two-species fermion mixtures with mass and population imbalance in continuum, trap and lattice models. In contrast with the crossover physics found in the mass and population balanced mixtures, I demonstrate the existence of phase transitions between normal and superfluid phases, as well as phase separation between superfluid (paired) and normal (excess) fermions in imbalanced mixtures as a function of scattering parameter and mass and population imbalance.

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Wang, Hao. « Analysis of the quasicontinuum method and its application ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:8bef60f0-74f1-44f5-bcbe-d64d4afad15f.

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The present thesis is on the error estimates of different energy based quasicontinuum (QC) methods, which are a class of computational methods for the coupling of atomistic and continuum models for micro- or nano-scale materials. The thesis consists of two parts. The first part considers the a priori error estimates of three energy based QC methods. The second part deals with the a posteriori error estimates of a specific energy based QC method which was recently developed. In the first part, we develop a unified framework for the a priori error estimates and present a new and simpler proof based on negative-norm estimates, which essentially extends previous results. In the second part, we establish the a posteriori error estimates for the newly developed energy based QC method for an energy norm and for the total energy. The analysis is based on a posteriori residual and stability estimates. Adaptive mesh refinement algorithms based on these error estimators are formulated. In both parts, numerical experiments are presented to illustrate the results of our analysis and indicate the optimal convergence rates. The thesis is accompanied by a thorough introduction to the development of the QC methods and its numerical analysis, as well as an outlook of the future work in the conclusion.

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Kruttli, Mathias Simon. « Essays on hedge fund illiquidity, return predictability, and time-varying risk exposure ». Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:236c2e23-5052-4046-bcb0-740d79c87232.

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This thesis consists of three papers that make independendet contributions to the field of financial economics. As such, the papers, Chapter 2, Chapter 3, and Chapter 4, can be read independently of each other. In Chapter 2, we construct a simple measure of the aggregate illiquidity of hedge fund portfolios, and show that it has strong in- and out-of-sample forecasting power for 72 portfolios of international equities, U.S. corporate bonds, and currencies, over the 1994 to 2011 period. The forecasting ability of hedge fund illiquidity for asset returns is, in most cases, greater than, and provides independent information relative to, well-known predictive variables for each of these asset classes. We construct a simple equilibrium model to rationalise our findings and empirically verify auxiliary predictions of the model. In Chapter 3, I analyse the risk-shifting of hedge funds. Since the information on hedge fund holdings is very restricted, researchers have used the variance of returns as a proxy for risk. I propose a new method for measuring the time-varying variance. I use this method to investigate whether equity long-short hedge funds engage in risk-shifting driven by their past performance relative to their peers. I find that hedge funds which have strongly underperformed or outperformed their peers in recent months increase their exposure to the core strategy, i.e. the equity long-short strategy, and to non-core strategies. The risk shifting is mitigated for hedge funds with long redemption periods. Chapter 4 contributes to the equity premium prediction literature. I improve the forecast performance of typical single variable predictive regressions used in the equity premium prediction literature through Bayesian priors derived from consumption-based asset pricing models. To implement these model-based priors, I develop a Bayesian procedure which is rooted in the macroeconometrics literature. I find that the model-based priors can increase the explanatory power, measured by the out-of-sample R², of the single variable predictive regressions by several percentage points.

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Soul, Laura Clare. « Phylogenetic interpretations of macroevolution in deep-time ». Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:49ef0bb4-bcb1-4eaa-94d4-29af8e9b6a39.

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The fossil record yields information on macroevolutionary patterns that remains inaccessible from the study of extant organisms alone, presenting a natural laboratory for us to test hypotheses about the long-term drivers and processes of evolution. Fossil data are therefore increasingly incorporated into evolutionary analyses, both on their own and in combination with neontological data. Phylogeny (an explicit hypothesis of the evolutionary relationships between taxa) can be used as a framework to enable direct comparison of results of comparative methods across many different timescales and taxa, and is now commonly used in investigations of fossil data. This represents an important step towards a unified approach, however, it is not yet fully understood what the effect of using fossil data is on the results of downstream phylogenetic comparative methods, which were originally developed with only living taxa in mind. In this thesis I explore the validity of phylogenetic interpretations of fossil record data. I begin with only taxonomic classification and show that this can in some cases substitute for a cladistically inferred phylogeny in phylogenetic comparative methods, without biasing results. Moving on to scenarios where a timescaled phylogeny is available I investigate the relationship between phylogeny and extinction in the geological past, show that phylogenetic clustering of extinction was common in tetrapods, and present a summary of the ways in which fossil data biases this measurement. Finally, with timescaled phylogenies and a detailed continuous trait dataset available, I interrogate the fossil record of Sauropterygia to uncover the processes of evolutionary change in this highly labile clade. By comparing the results of a suite of phylogenetic comparative methods I demonstrate that neck length evolved through changing vertebral counts rather than somite growth; that the clade experienced a release in evolutionary constraint at the Triassic-Jurassic boundary; and that evidence does not support evolution towards a stationary adaptive peak as a suitable model for phenotypic change in the clade.

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Šuhada, Róbert [Verfasser], et Hans [Akademischer Betreuer] Boehringer. « The XMM-BCS galaxy cluster survey / Róbert Šuhada. Betreuer : Hans Boehringer ». München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1015169961/34.

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Kipper, Carla Judite. « Vidro de spin e antiferromagnetismo com interacão de pareamento BCS local ». Universidade Federal de Santa Maria, 2005. http://repositorio.ufsm.br/handle/1/9183.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In this work the competition among spin glass(SG), antiferromagnetism (AF) and BCS pairs formation (PAIR) in real space is investigated. The model consists of an Ising spin glass term and a local BCS term that favors double site occupation. This model is composed by two sublattices, but only spins in diferent sublattices can interact. The Ising coupling is a random variable Jij that follows a gaussian probability distribution with average - J0=N and variance J²=N. The problem is formulated in terms of functional integral formalism, where the spin operators are written as bilinear combination of Grassmann felds. Using the replica method and the static approach for the spin-spin correlation functions, we obtain the grandcanonical potential. The results are presented in phase diagrams which show T=J versus g=J for several values of J0=J (where T is the temperature and g is the pairing strength interaction). The order parameters solution indicate the PAIR phase (double ocupation of sites) when g=J is sufciently high. As the value of g=J decreases, the problem presents antiferromagnetic or spin glass solution, that dependis on the ratio J0=J. For high temperatures and any value of J0, we obtain paramagnetic solution. For values of J0 ≤ 1:5J, the SG solution appears at temperature Tf = 0:96J. In the range 1:5J < J0 ≤ 1:7J, the AF phase appears between the paramagnetic and spin glass solutions. The spin glass solution is not found when J0 > 1:7J.
Neste trabalho investiga-se a competição entre vidro de spin (SG), antiferromagnetismo (AF) e formação de pares do tipo BCS (PARES) no espaço real. O modelo consiste em um acoplamento Ising juntamente com um termo BCS local que favorece a dupla ocupação dos sítios. Neste modelo composto por duas sub-redes, o acoplamento ocorre unicamente entre spins localizados em sub-redes diferentes. O termo que acopla os spins é uma variável aleatória Jij com uma distribuição de probabilidade gaussiana, sendo a média dada por - JO=N e a variância por J²=N. O problema é formulado em termos das integrais funcionais, onde as variáveis de spin são escritas como combinações bilineares dos campos de Grassmann. Utilizando o método das réplicas e a aproximação estática para as funções correlação spinspin, obtemos o potencial grande canônico por sítio. Os resultados são apresentados através de diagramas de fases T=J versus g=J para vários valores de JO. Em todos os diagramas, quando g=J é suficientemente grande, as soluções das equações para os parâmetros de ordem indicam a presença da fase de formação de pares. À medida que diminui o valor de g=J, o problema apresenta como solução antiferromagnetismo e/ou vidro de spin, dependendo da razão JO=J. Para altas temperaturas e qualquer valor de JO, temos solução paramagnética, com m e q nulos. Para valores de JO ≤ 1; 5J, aparece a solução vidro de spin em temperatura Tf = 0; 96J. No intervalo de 1; 5J < JO ≤ 1; 7J surge uma fase antiferromagnética entre as soluções paramagnética e vidro de spin. Quando JO > 1; 7J a solução vidro de spin desaparece.

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Soundararajan, R. « Enhancing the bioavailability of BCS Class IV drugs using polymeric nanoparticles ». Thesis, University College London (University of London), 2016. http://discovery.ucl.ac.uk/1479729/.

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Hydrophobic drugs that are P-gp substrates (BCS Class IV) such as paclitaxel, CUDC-101 etc. pose a serious challenge for oral drug delivery. Polymeric amphiphiles such as N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ) are capable of enhancing the bioavailability of hydrophobic drugs by forming nanoparticles. The general hypothesis is that the physicochemical properties of the polymer will affect the colloidal stability, encapsulation efficiency and absorption of hydrophobic drugs. The main aims of the project are as follows: a) to examine the feasibility of using GCPQ with different characteristics, for the oral and subcutaneous delivery of CUDC-101 and b) to examine the effect of N-(2-phenoxyacetamide)-6-O-glycolchitosan (GCPh) on the P-gp efflux of paclitaxel. GCPh, a new polymeric amphiphile was synthesized by conjugating glycol chitosan to phenoxy acetic acid. Paclitaxel and CUDC-101 were encapsulated with GCPh and GCPQ of different molecular weights and hydrophobicity. The in vivo oral drug absorption profile for paclitaxel-GCPh nanoparticles and paclitaxel-Taxol® nanoparticles were determined in mice with and without verapamil, a P-gp inhibitor. In another study, the oral and subcutaneous drug absorption profile for CUDC-101 – GCPQ nanoparticles were conducted in mice and rat models respectively. Results indicated that GCPh improved the oral absorption of paclitaxel by improving the dissolution and promoting particle uptake through enterocytes. Experiments with Taxol® suggested that it is possible to saturate the P-gp pumps by improving the drug’s dissolution. Oral absorption of CUDC-101 was poor due to the drug’s extremely poor water solubility. The subcutaneous absorption of CUDC-101 – GCPQ nanoparticles were excellent. The colloidal stability and absorption of these nanoparticles can be improved by increasing polymer concentration and its hydrophobicity. These nanoparticles also prolonged the life span of human A431 tumour bearing mice by 28 days (p < 0.001). To conclude, the new polymeric amphiphile (GCPh), capable of improving the oral absorption of BCS Class IV P-gp substrates was developed. A new strategy to nullify the P-gp efflux was developed. A clinically relevant subcutaneous dosage form for CUDC-101 was also successfully developed.

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Varon, Mauricio Pardo 1984. « Estudo de uma bomba centrífuga submersa (BCS) como medidor de vazão ». [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265668.

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Orientador: Antonio Carlos Bannwart
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências
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Resumo: O Bombeio Centrífugo Submerso (BCS) é um dos métodos mais importantes de elevação artificial de petróleo, no Brasil e no mundo. A bomba de BCS é acionada por um motor elétrico acoplado diretamente ao eixo da bomba. Comumente, possui também um conjunto de sensores que fazem o monitoramento da operação do motor, além de outras variáveis próprias como, por exemplo, o ganho de pressão gerado pela BCS. Por outro lado, a operação remota do motor na superfície se dá através de um inversor de frequência que fornece, além da rotação, o consumo elétrico da BCS. A medição da vazão de líquido produzida por cada poço é tradicionalmente realizada com instrumentação especializada de alto custo. Dado que o sensor do motor da BCS e o inversor de frequência que a opera já fornecem informações utilizadas para o monitoramento do equipamento e para o gerenciamento do poço, a vazão de líquido local na BCS poderia ser determinada com base em curvas de desempenho previamente levantadas nas condições de operação esperadas. O ganho de pressão gerado pela BCS e a potência elétrica consumida pelo motor que a aciona são as variáveis de desempenho consideradas neste estudo para avaliar a incerteza da vazão de líquido local estimada através da bomba em diversas condições de operação (incluindo escoamento bifásico e viscoso). A avaliação é feita com base na norma API RP 11S2, que estabelece as práticas recomendadas para testes de BCS
Abstract: ESP (Electrical Submersible Pump) is one the most important artificial lift methods for oil in Brazil and worldwide. The centrifugal pump is driven by an electric motor directly coupled to the pump shaft. Commonly, also has a set of sensors that monitor the electric motor operation, and other variables themselves, for example, the pressure gain generated by the ESP. Moreover, the remote operation of the equipment at the surface is performed via a frequency inverter that provides, in addition to the rotation, the power consumption of the ESP. Measurement of liquid flow rate produced by each well is traditionally performed with specialized instrumentation costly. As the motor sensor and the frequency inverter that drives the ESP already provide information used for monitoring equipment and for managing the well, the local liquid flow rate in the ESP could be determined based on correlations with these data. The pressure gain generated by the ESP and electrical power consumed by the motor are the considered variables for this study to correlate with the flow rate of fluid produced and to assess the quality of the results by analyzing uncertainties. To achieve this, a series of performance curves are obtained at different operating conditions (including two-phase flow and viscous) to observe how the uncertainty of the results are affected by correlated variables. The assessment is based on the standard API RP 11S2, which establishes best practices for testing BCS
Mestrado
Explotação
Mestre em Ciências e Engenharia de Petróleo

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Oliveira, Marcos Kelvin Lira de, et 92-99404-7597. « Os efeitos da hibridização no crossover BCS-BEC com interações interbandas ». Universidade Federal do Amazonas, 2018. http://tede.ufam.edu.br/handle/tede/6225.

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In this work we discuss the behavior of a superconducting system described by a multiband model, so it is an extension of the BCS theory which describes well the low temperature superconductors. We consider the interbanding interaction, that is, the interaction between fermions that present different properties under the influence of hybridization, evaluating the crossover between the weak coupling (BCS) and the strong coupling (BEC) for symmetry type s Order parameter in T = 0 and in the presence of a hybridization. However, the objective of this work is to study superconductivity without a two-band model, with interband interactions, with the purpose of obtaining as equations for the superconducting Gaps and, concomitantly, to evaluate a development of the systems between the limit of weak couplings (BCS) and strong couplings (BEC) and estimate an influence that is a hybridization on the system. Using Zubarev's Green function method, we calculate interband superconducting order parameters and chemical potential as a function of the interaction 1/kpa, in order to obtain a complete study of the system. We explore the energies of excitation at the two limits of the coupling, considering their characteristics and we see that there is a discontinuity in the amplitude of the interband gap. Our results suggest that hybridization V acts at the expense of superconductivity, suppressing it, agreeing with other works, although this is not general, since some works show that V contributes to superconductivity up to a certain value and to other values, destroys it. We also notice that in interband interaction we have first and second order transitions and a tricritic point, in which We have the encounter of a first order line with a second order line.
Neste trabalho é tratado o comportamento de um sistema supercondutor descrito por um modelo multibandas, sendo isto uma extensão da teoria BCS a qual descreve bem os supercondutores de baixas temperaturas. Uma vez que a mesma se limita ao caso de uma única banda. Será Considerado a interação interbanda, isto é, a interação que se dá entre férmions que apresentam propriedades diferentes, sob a influência da hibridização, avaliando o crossover entre os limites de acoplamento fraco (BCS) até o acoplamento forte (BEC) para simetria tipo s do parâmetro de ordem em T = O. Portanto, o objetivo deste trabalho é estudar a supercondutividade no modelo de duas bandas, com interações interbandas, com o propósito de obter as equações para as amplitudes do gap supercondutor e, concomitantemente, avaliar a evolução dos sistemas entre o limite de acoplamentos fracos (BCS) e acoplamentos fortes (BEC) e estimar a influência que a hibridização tem sobre o sistema. Fazendo uso do método das funções de Green de Zubarev, calculamos os parâmetros de ordem supercondutor interbandas e o potencial químico como função da interação, a qual será descrita em termos do comprimento de espalhamento e do número de onda de Fermi, afim de obtermos um estudo completo do sistema. Exploramos as energias de excitação nos dois limites do acoplamento, considerando suas características e vimos que existe uma descontinuidade na amplitude do gap inter-banda. Nossos resultados sugerem que a hibridização V, atua em detrimento da supercondutividade, suprimindo-a, concor-dando com outros trabalhos, apesar de não ser isso geral, uma vez que alguns trabalhos mostram que V contribui para a supercondutividade até um determinado valor e para outros valores, a destrói. Percebemos também que na interação interbanda temos transições de primeira e segunda ordem e um ponto tricrítico, no qual temos o encontro de uma linha de primeira ordem com uma de segunda ordem. Este trabalho se baseia na tese do Professor Dr. Francisco Dinola.

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48

Hannan, Mohammad Abdul. « Sparse Processing Methodologies Based on Compressive Sensing for Directions of Arrival Estimation ». Doctoral thesis, Università ; degli studi di Trento, 2020. http://hdl.handle.net/11572/278178.

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In this dissertation, sparse processing of signals for directions-of-arrival (DoAs) estimation is addressed in the framework of Compressive Sensing (CS). In particular, DoAs estimation problem for different types of sources, systems, and applications are formulated in the CS paradigm. In addition, the fundamental conditions related to the ``Sparsity'' and ``Linearity'' are carefully exploited in order to apply confidently the CS-based methodologies. Moreover, innovative strategies for various systems and applications are developed, validated numerically, and analyzed extensively for different scenarios including signal to noise ratio (SNR), mutual coupling, and polarization loss. The more realistic data from electromagnetic (EM) simulators are often considered for various analysis to validate the potentialities of the proposed approaches. The performances of the proposed estimators are analyzed in terms of standard root-mean-square error (RMSE) with respect to different degrees-of-freedom (DoFs) of DoAs estimation problem including number of elements, number of signals, and signal properties. The outcomes reported in this thesis suggest that the proposed estimators are computationally efficient (i.e., appropriate for real time estimations), robust (i.e., appropriate for different heterogeneous scenarios), and versatile (i.e., easily adaptable for different systems).

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49

Thomson, Thomas Michael. « The death and life of the Little Mountain Housing Project : BC's first public housing community ». Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/30445.

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Opened in 1954, Vancouver’s Little Mountain Housing Project was the first public housing project in BC and among the oldest in Canada. For more than half a century, Little Mountain provided subsidized rental housing for low and moderate income families and seniors. Throughout its years, Little Mountain was at the forefront of housing policy in BC. Little Mountain’s initial development in the 1950s spelled out how the federal-provincial public housing partnership would operate in BC. In the 1970s Little Mountain was the first public housing project in Canada managed by a committee of tenants. And today Little Mountain continues to be on the leading edge of provincial housing policy as it is the first public housing project to be privatized and redeveloped under a new province-wide policy announced in 2007. Redevelopment and privatization have involved the displacement of 194 Little Mountain households and the demolition of all but one of the buildings at Little Mountain. The displacement of the tenants and the near total clearance of the large site are among some of the disturbing similarities between the redevelopment of Little Mountain and the old urban renewal programs of the mid-twentieth century. But unlike urban renewal, the redevelopment of Little Mountain is connected to neoliberal restructuring and the erosion of the welfare state. When Little Mountain is eventually rebuilt, it will feature a mixed-income community that will combine social housing tenants and market homeowners. Redevelopment has been justified, in part, on the basis that social mixing will create more social capital for the low-income families at Little Mountain. But this thesis shows that Little Mountain was already remarkably rich in social capital. In contrast to the stereotype of the ‘troubled housing project’, Little Mountain offered a very supportive, happy, and beautiful living environment. Ironically, displacement has isolated many of the tenants. Through an analysis of the distribution of benefits and losses of redevelopment to various relevant groups, this thesis shows that the Little Mountain tenants are being squeezed out of the benefits of redevelopment while bearing significant losses.

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Monte, Verde William 1987. « Estudo experimental de bombas de BCS operando com escoamento bifásico gás-líquido ». [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264613.

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Orientador: Antonio Carlos Bannwart
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: A utilização de bombas centrífugas submersas (BCS) operando com a mistura gás-líquido é comum na indústria de petróleo. Para elevadas vazões de líquido e baixas frações de gás o desempenho da bomba é similar ao escoamento monofásico. No entanto, uma degradação severa no desempenho é observada para elevadas frações de gás. A presença de gás livre no escoamento causa instabilidades na curva de ganho de pressão versus vazão. A curva passa a exibir um ponto de máximo, conhecido como ponto de 'surging', sendo que para vazões abaixo desse ponto, ocorre uma acentuada queda no ganho de pressão e, portanto, na capacidade de bombeamento. O aumento da vazão de gás pode causar o bloqueio da área disponível ao escoamento no rotor da bomba, fazendo com que a vazão seja nula, fenômeno conhecido como 'gas locking'. Portanto, o conhecimento das condições operacionais onde ocorre o surging é de fundamental importância para a operação adequada da bomba. O objetivo deste trabalho é obter as curvas de desempenho (elevação, potência e rendimento) de BCS operando com misturas gás-líquido. Com esse propósito as curvas característica de um protótipo de BCS foram determinadas utilizando a mistura água-ar, com frações volumétricas de gás entre 0 e 10% em diferentes rotações, pressões de sucção e vazões de líquido. O protótipo de BCS foi desenvolvido a partir de uma bomba convencional permitindo a visualização do escoamento no interior da bomba. Um manuseador de gás também foi testado buscando determinar suas características operacionais. Os ensaios foram realizados em uma bancada de testes, onde foram medidas os parâmetros do escoamento (vazões de ar e água, pressão e temperatura na entrada e saída da bomba) e parâmetros mecânicos (torque de velocidade de rotação). Uma severa degradação no desempenho, e consequentemente no rendimento da bomba foram observados devido à presença de gás no escoamento. Os fenômenos de surging e gas locking também foram observados durante os testes. A velocidade de rotação e a pressão de sucção influenciaram a fração volumétrica onde o surging ocorre. O aumento da velocidade de rotação e da pressão de sucção desloca a fração volumétrica critica de gás para valores mais elevados, aumentando a faixa operacional da bomba
Abstract: The use of electrical submersible pumps (ESP) under gas-liquid flow is very common in the oil industry. At constant liquid flow rate a dramatic degradation on pump head is observed as gas flow rate increases. Natural instabilities of two-phase flow may cause the centrifugal pump to surge at rather low gas void fraction (GVF), as evidenced by a critical point in the pressure gain x flow rate curve, a phenomenon referenced as 'surging point'. Further increase in GVF may cause the gas to fill most of the pump impeller, making the liquid flow rate to decrease down to zero, a phenomenon known as 'gas locking'. Therefore, knowledge of the conditions for which the pump starts to surge is of utmost importance and can only be understood through experimental investigation. The goal of this work is to present the experimental ESP performance curves (head, brake horsepower and efficiency) when operating with gas-liquid mixtures. For that purpose the characteristic curves were determined for one prototype of ESP, operating with water and two-phase air-water mixtures with GVF ranging from 0 to 10 % at different rotational speed, intake pressure and liquid flow rate. The ESP prototype is designed to make possible the flow visualization inside the pump. The performance of a gas handler was also tested in order to determine their operational characteristics. Tests were carried out on an ESP testing bench, where flow parameters (air and water flow rates, pressure and temperature at the inlet and outlet of the pump) and mechanical parameters (shaft torque and speed) were measured. A significant decrease in pump head, and consequently in pump efficiency, was observed as the air fraction was increased. Phenomena like surging and gas locking were observed during these tests. The rotational speed and intake pressure affect the critical GVF at the surging conditions. Increasing the rotational speed and intake pressure moves de critical GVF to higher values extending the operational range the ESP
Mestrado
Explotação
Mestre em Engenharia de Petróleo

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