Este trabalho apresenta um estudo através da abordagem Bayesiana em modelos de volatilidade estocástica, para modelagem de séries temporais financeiras, com o uso do método de Monte Carlo Hamiltoniano (HMC). Propomos o uso de outras distribuições para os erros da equação de observações do modelos de volatilidade estocástica, além da distribuição Gaussiana, para tratar problemas como caudas pesadas e assimetria nos retornos. Além disso, utilizamos critérios de informações, recentemente desenvolvidos, WAIC e LOO que aproximam a metodologia de validação cruzada, para realizar a seleção de modelos. No decorrer do trabalho, estudamos a qualidade do método HMC através de exemplos, estudo de simulação e aplicação a conjunto de dados. Adicionalmente, avaliamos a performance dos modelos e métodos propostos através do cálculo de estimativas para o Valor em Risco (VaR) para múltiplos horizontes de tempo. / This paper presents a study using Bayesian approach in stochastic volatility models for modeling financial time series, using Hamiltonian Monte Carlo methods (HMC). We propose the use of other distributions for the errors of the equation at stochastic volatiliy model, besides the Gaussian distribution, to treat the problem as heavy tails and asymmetry in the returns. Moreover, we use recently developed information criteria WAIC and LOO that approximate the crossvalidation methodology, to perform the selection of models. Throughout this work, we study the quality of the HMC methods through examples, simulation study and application to dataset. In addition, we evaluated the performance of the proposed models and methods by calculating estimates for Value at Risk (VaR) for multiple time horizons.

The purpose of this Master’s thesis is to examine the portrayals of class in four Swedish contemporary novels that have been mentioned as working class literature in the literary public sphere. During the 20th century, society has undergone vast changes due to globalization and technology development. The rise in standards of living for most people in the Western societies has led to changed consumption patterns. In consequence, there has been increased emphasis given to cultural rather than materialist explanations of social stratification. The theoretical approach of this study is based on class theories that emphasize either materialist or cultural explanations of social stratification. The methodology used is based on the analysis of ideas. In order to examine the portrayals of class in the four novels, an analysis scheme has been constructed on the bases of theories of Marx, Weber, Bourdieu and Giddens. The ideal types used are as follows: Economic capital, Cultural capital, Class in itself – class for itself, Production, exploitation, profit, Consumption, lifestyles, taste, Status and Societal change. The study argues that in spite of the fact that cultural conditions such as cultural capital and consumption patterns are evident markers of class belonging, the determining factor for class belonging is economic conditions, especially for the underclass. It also argues that the main purpose of contemporary working class literature is to criticize the class society and social inequity. Another central theme is societal change and how this affects working life and social stratification. The novels are permeated with the dichotomies we – they and power – powerlessness. There is a pessimistic picture of society that appears in the novels, where solidarity has disappeared and the characters express feelings of resignation and despair. / Uppsatsnivå: D

Thesis (Ph.D.)--Ohio University, November, 2007. / Title from PDF t.p. Includes bibliographical references.

Thesis (M. Dev.) --University of Limpopo, 2016 / The purpose of this study was to investigate the social factors that affect the acceptability of the Enviro Loo sanitation technology in schools. The study adopted the anti-positivism theory. Phenomenology school of thought was used as one of the three schools of thoughts as marked under Anti-positivism. The qualitative research method had its foothold in the fact that social factors, as a human activity, occurs in a particular natural and social environment. Utilising the qualitative research design, the researcher focused on describing and understanding the social factors that influence the acceptability of the Enviro Loo sanitation technology at schools. The study utilised an interview guide to collect data. The advantage of this is that it allowed the researcher to probe and ask for clarification of some answers as given by the respondents The population of this study comprised 35 secondary schools in Limpopo Province that benefited from the implementation of the Enviro Loo sanitation technology system during the 2010/11 financial years. Non-probability sampling was used. The method used to select the schools was convenience sampling as a non-probability sampling technique where subjects are selected because of their convenient accessibility and proximity to the researcher. This is because the researcher was bound by time, money and workforce and because of these limitations, it was almost impossible to randomly sample the entire population. Three sets of focus groups were used as sample, namely; the Provincial Sanitation Task Team (PSTT), School Governing Body (SGB) and Leaner’s Representative Council (LRC). All groups were gender balanced and members participated voluntarily. Nvivo was utilised to analyse data. The audio recordings from the digital voice recorder were transcribed, translated into English, typed into word and thematic analysis was used.

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Orientador: Milton Mori / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-10T02:03:13Z (GMT). No. of bitstreams: 1 Dionisio_RenatoPrado_M.pdf: 2692662 bytes, checksum: d52cd80b3a64bf352c034ca0e8b2835e (MD5) Previous issue date: 2007 / Resumo: Colunas de bolhas são equipamentos utilizados para realizar operações de transferência de massa e/ou calor entre uma fase gasosa e uma fase líquida, ou entre uma fase gasosa e uma fase sólida dissolvida ou suspensa na fase líquida com ou sem reação química. Elas são equipamentos de simples operação, mas que apresentam uma fluidodinâmica bastante complexa. Seu funcionamento básico é dado pela injeção de um gás (fase dispersa) na base da coluna em um meio líquido (fase contínua). Elas são empregadas nas mais diversas áreas industriais, como processos de química fina, reações de oxidação, reações de alquilação, síntese de Fischer-Tropsch, tratamento de efluentes, reações de fermentação e produção de proteínas, e mais recentemente, em cultura de células devido à sua simplicidade de construção e operação. Processos que utilizam esse tipo equipamento se aproveitam das vantagens que eles apresentam como o fato de não possuírem partes móveis e propiciarem uma grande área de contato entre as fases e conseqüentes taxas elevadas de transferência de massa e calor, o que favorece tanto as reações químicas quanto as biológicas. O objetivo deste trabalho foi analisar computacionalmente, através da fluidodinâmica computacional (CFD), a influência de parâmetros geométricos (diferentes tipos de distribuidor de fase gasosa e recirculação externa da fase líquida na coluna) na fluidodinâmica do sistema. Foram realizadas simulações tridimensionais de colunas de bolhas empregando o pacote computacional ANSYS/CFX 5.11 que utiliza o método dos volumes finitos na discretização das equações diferenciais que governam o escoamento em colunas de bolhas de escala de laboratório. Foi observado que a inclusão de distribuidores de fase gasosa na malha computacional acarretou em melhor predição dos perfis de fração volumétrica de gás nas colunas, resolvendo os problemas de aproximações geométricas arbitrárias sobre a forma de se distribuir o gás pela coluna em casos que a simples injeção uniforme apresenta problemas. A utilização dessa abordagem, no entanto, deve ser cuidadosamente considerada devido ao aumento do esforço computacional. Também foi observada uma mudança notável no comportamento do perfil de velocidade axial da fase líquida devido à utilização de uma recirculação externa à coluna (External Loop), acarretando um decréscimo no valor total de fração volumétrica de gás na coluna (Total gas hold-up). No equipamento com o "Externalloop", o perfil de velocidade axial do líquido é ascendente em todo o corpo principal da coluna, diferindo das colunas cilíndricas verticais que possuem fluxo ascendente no centro da coluna e descendente nas regiões próximas às paredes. Os resultados mostraram que a metodologia utilizada no trabalho é adequada e capaz de prever comportamentos importantes nos equipamentos bifásicos em questão / Abstract: Bubble columns are equipments used to perform mass and heat transfer operations between a gas and a liquid phase, or between a gas phase and a solid phase dissolved or suspended in the liquid phase with or without chemical reaction. They are of simple operation, but offer room for a quite complex multiphase flow. Its basic operation is given by the injection of a gas phase (dispersed phase) at the base of the column passing through a liquid medium (continuous phase). They are employed in a broad variety of industrial sectors, such as processes of fine chemicals, oxidation reactions, alkylation reactions, Fischer- Tropsch synthesis, effluents treatment, fermentation and production of proteins and more recently in cell culture because of its simplicity of construction and operation. Processes that use such equipment take advantage of the fact that they have no moving parts and offer a high contact area between phases and consequent elevated mass and heat transfer rates, which favours both chemical and biological reactions. 'The goal of this study is to use computational fluid dynamics (CFD) to examine the influence of geometric parameters (different types of gas spargers and a liquid phase external loop recirculation) and some approximations usually made in computational studies published in the literature. In this work three-dimensional simulations of bubble columns were performed using ANSYS/CFX 5.11 computational package, which handles the finite volume method for discretizing the differential equations representing the flow in order to study laboratory scale bubble columns. It was observed that the inclusion of gas spargers in the computational mesh of bubble column simulations improved the description of the gas volume fraction profiles in the columns and solved the problems of arbitrary decisions on how to distribute the entering gas in cases where the simple uniform injection present problems. Using this approach, however, should be considered with care due to additional computational effort needed to achieve the desired solution. There was also a remarkable change in the behavior of the liquid phase axial velocity profiles due to the use of an external loop to the column, causing a decrease in the value of the total amount of gas present in the column (Total gas holdup). In the external loop equipment, the liquid axial velocity profile is upward throughout the entire main column, differing from cylindrical vertical columns in which the liquid flow is upward at the center of the column and is downward in regions near the walls. The results showed that the methodology used in this work is adequate, and able to predict bubble column and other two-phase equipment behaviour / Mestrado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

Purpose – This study aims to look into how foreignness and outsidership affect the market entry of a SME and the individual firm's ability to access the correct network as well as look at which support structures are available for the individual firms entering into a new market. Theory/Design & Research Questions – By looking through the lens of Social Network theory, aspects of trust, legitimacy, nodes, foreignness and outsidership, this study has looked into the journey of a large hamburger chain in Sweden that has successfully entered into different markets outside of Sweden. The research questions explored were (i) how SMEs can overcometheir liabilities and leverage network connections to form strategic partnerships with other firms or organizations, and (ii) how centrality of nodes can be utilized by SMEs to gain access to valuable information and resources, and (iii) how intermediary networks can support SMEs in their efforts to enter new markets, and what policies and programs have proven effective in this regard. Methodology – The data was gathered using a non-probability sampling by conducting a semi-structured qualitative interview and was complemented with secondary sources from the company profile. Findings – Depending on the size of the firm the level of ability to access networks can differ. Smaller firms are more inclined to seek help from intermediaries compared to larger firms. Furthermore actors that are more central have been found to have a key role for firms entering foreign markets.

Modernitet har ofta skildrats i litteraturhistorien med hjälp av en sammanbindning mellan panoramavy och bildningsresa. Ettsärskilt narrativ återkommer i sådana berättelser: protagonisten kämpar för att hitta genom storstadens myllrande gator, blir så småningom bekant med democh fullföljer därmed sin bildningsresa. Detta symboliseras genom en panoramavy över staden. Uppsatsen undersöker Hassan Loo Sattarvandis Still (2008), vilken använder panoramavyn i sin skildring av Stockholmsförorten Hagalund men tematiserar monotoni i stället för den förändring som tematiseras i skönlitteratur om moderniteten. Syftet med uppsatsen är att diskutera i vilken utsträckning denna kontrast beror på stadsplaneringen i Hagalund och vad ett sådant samspel mellan monotoni och miljö innebär för skildringen av modernitet. Genom geokritisk metod, vilken analyserar hur miljön påverkar berättelsen genom karaktärers rörelsemönster, framträder stadsplaneringen som gemensam komponent mellan de återkommande panoramavyerna, moderniteten, bildningsresan, flanerande och slutligen monotonin som tematik. Stadsplaneringen i romanen är nämligen utformad för att stävja moderniteten, och förlagan till utformningen härrör ur panoramavyn som uttryck för kontroll. Detta resulterar i att protagonisten i Still flanerar i cirklar och aldrig kan fullfölja sin bildningsresa, vilket symboliseras med en konstant panoramavy. Monotonin som tematik integreras och binds således till romanens miljö för att uttrycka segregation, avsaknad av utvecklingspotential och en avstannad modernitet. Uppsatsens bidrag består i en ny läsning av romanen, i vilken tematiken är bunden till sin miljö, som bör skänka nytt ljus till svensk arbetarlitteratur och läsningar av förortsskildringar i stort.

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