Purchasing Power Party (PPP) has long been intensively studied in empirical researches. However, a unanimous conclusion has not been reached. As an alternative to a narrative literature review, this paper conducts a meta-regression analysis of a collection of thirty-three studies, in order to uncover the sources of variation in the empirical findings relating to PPP. We also test the validities of suggestions made by the narrative literature reviewers that the use of more years of data, more countries, more powerful tests, more general model specifications, and an allowance for non-linearity might mitigate the issue of PPP puzzle. We find that the proposition is true and that whether PPP holds in the long run mainly depends on the methodology employed, the regimes the data are sampled from, and the length of the sample of data that is used. When addressing the persistence of the deviations from PPP, it mostly depends on the methodologies adopted.

This study aims to find out how gender roles are portrayed in the series The Walking Dead. Using a quantitative content analysis where every episode of The Walking Dead was analyzed the study shows gender role portrayal in the everyday activities done by the characters. A qualitative study based on a semiotic analysis was also executed where focus lies on analyzing the characters attributes and their trait of character. The result shows that the series maintains a stereotypical representation of men and women. The men take on the typical “manly” work and the women do the majority of the domestic work. The killing of zombier and humans are mostly done by the men in the series. Their trait of character also shows a stereotypical gender role representation where the men are portrayed as tough, fighters, protectors and providers. The women on the other hand are more weak, sensitive and dependent.

Diffusion tensor imaging (DTI) is a structural magnetic resonance imaging (MRI) technique to record incoherent motion of water molecules and has been used to detect micro structural white matter alterations in clinical studies to explore certain brain disorders. A variety of DTI based techniques for detecting brain disorders and facilitating clinical group analysis have been developed in the past few years. However, there are two crucial issues that have great impacts on the performance of those algorithms. One is that brain neural pathways appear in complicated 3D structures which are inappropriate and inaccurate to be approximated by simple 2D structures, while the other involves the computational efficiency in classifying white matter tracts. The first key area that this dissertation focuses on is to implement a novel computing scheme for estimating regional white matter alterations along neural pathways in 3D space. The mechanism of the proposed method relies on white matter tractography and geodesic distance mapping. We propose a mask scheme to overcome the difficulty to reconstruct thin tract bundles. Real DTI data are employed to demonstrate the performance of the pro- posed technique. Experimental results show that the proposed method bears great potential to provide a sensitive approach for determining the white matter integrity in human brain. Another core objective of this work is to develop a class of new modeling and clustering techniques with improved performance and noise resistance for separating reconstructed white matter tracts to facilitate clinical group analysis. Different strategies are presented to handle different scenarios. For whole brain tractography reconstructed white matter tracts, a Fourier descriptor model and a clustering algorithm based on multivariate Gaussian mixture model and expectation maximization are proposed. Outliers are easily handled in this framework. Real DTI data experimental results show that the proposed algorithm is relatively effective and may offer an alternative for existing white matter fiber clustering methods. For a small amount of white matter fibers, a modeling and clustering algorithm with the capability of handling white matter fibers with unequal length and sharing no common starting region is also proposed and evaluated with real DTI data.

Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.

Milk contains high concentrations of calcium. It occurs in two forms, a free ionic form, and calcium associated with milk proteins (caseins). The latter association is called colloidal calcium phosphate. New Zealand Dairy Foods of Takanini is marketing a range of commercial milks in supermarkets. The company uses ultra filtration to concentrate milk proteins and calcium in different milk products. During ultra filtration, the fraction that is retained by the membrane is rich in calcium bound to proteins and the portion that passes through the membrane is richer in the free ionic form. The company wanted to develop a quick and an economical method that can be applied in industrial settings to determine calcium in both these fractions and in other milk products. This research aimed to develop a quick, wet chemistry method to measure calcium in milk fractions and to trial it in an industrial environment. Two methods, the so-called EDTA method and the atomic absorption spectrophotometric method (AA) were trialled as potential reference methods against which to compare results obtained by the method to be developed. The AA method was chosen due to its ease, accuracy and precision. (This could not be selected as the industrial method for a number of reasons.) A colorimetric method was favoured over other contenders. Two colorimetric dyes, Arsenazo I and o-cresolphthalein-complexone (CPC) were chosen to work with. Arsenazo I forms a purple complex with calcium in a suitable buffer at a range of pHs. o-Cresolphthalein-complexone also forms purple-coloured complexes at alkaline pHs. During method development with Arsenazo I, different buffers were trialled and a NaOH/ KCl buffer was selected for further development at pH 12. The method worked well during the development phase but with some inconsistent results at times. o-Cresolphthalein-complexone formed clear purple complexes with Clark and Lubs and 2-amino-2-methylpropanol (AMP) buffers. The key advantage of the CPC dye with AMP buffer was that when 8-hydroxyquinoline was included in the reaction mixture, it successfully masked coloured complex formation due to CPC with magnesium, which is present in milk at about 1/3 the calcium concentration. This effect did not work with Arsenazo I. However, the results obtained with the CPC method were lower than claimed values of most milks trialled during development. Both methods were compared for their precision and it was found that CPC method has better precision and was chosen for further development. To improve the accuracy and precision, various denaturing reagents were used to (hypothetically) release calcium from the caseins. Trichloroacetic acid at 25 % was more effective than the several other denaturing treatments tested. The finalised CPC method, using trichloroacetic acid, AMP and 8-hydroxyquinoline, was then used to monitor calcium concentration over four months in three milk products, skim, Xtra (retentate) and permeate. For all milks, the CPC values were lower than the AA reference values, and the values reported by a commercial analytical laboratory. The reasons for this are discussed, as are other changes in calcium concentration in the three milks throughout the trial. The correlation between the CPC and AA values was poor for Xtra, better for skim, and best for permeate. A chemical model to explain this is discussed. The method developed is cheap and quick, and sample and reagent preparation is simple. The method could be applied in an industrial environment, but a proportionality factor would have to be applied to account for the difference in mean values between the CPC and AA methods.

Diss. (sammanfattning) Skara : Sveriges lantbruksuniv., 2002. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.

Lic.-avh. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2004. / Härtill 3 uppsatser.

Modernas provedoras de serviços de TI estão sob constante pressão para aumentar sua competitividade. Meios de reduzir os custos e aumentar o desempenho (i.e., produtividade e qualidade) dos serviços oferecidos são temas centrais na indústria de TI. Contudo, apesar de todos os esforços feitos até hoje, modelar e otimizar processos de TI que envolvem operadores humanos continua sendo uma tarefa complexa. O humano pode ser influenciado por inúmeros fatores e executar o processo de uma forma diferente a cada vez, portanto, introduzindo uma significativa variabilidade no resultado final do processo. Apesar de todas as pesquisas feitas até hoje terem introduzido melhorias significativas no gerenciamento de serviços, ainda restam muitos desafios (e.g., mudanças rápidas, limites orçamentários, falta de conhecimento, complexidade dos sistemas, atuais e futuros requisitos dos usuários e finalmente aumento nas expectativas dos usuários) que não foram completamente resolvidos pelos esforços atuais. Dentre todas as tecnologias disponíveis atualmente, uma em especial, conhecida como Web 2.0, ainda não foi investigada pela indústria e pela acadêmia no contexto da gerência de serviços de TI. Dentre todas as tecnologias e aplicações que definem aWeb 2.0, uma é de especial interesse nesta tese: os mashups. Mashups sao aplicacoes Web criadas a partir da composicao de recursos disponiveis online (e.g., mapas interativos, Web services, paginas HTML). Facilidade de uso, extensibilidade e desenvolvimento específico de contexto são exemplos de características apresentadas pelos mashups que os candidatam como uma solução viável para aprimorar o gerenciamento de serviços de TI. Desta forma, o objetivo desta tese é investigar a aplicabilidade de mashups como uma solução efetiva para melhorar o desempenho (i.e., em termos de produtividade e confiabilidade) de atividades de gerência de serviços de TI que envolvem operadores humanos. Em particular, esta tese tem como objetivo definir soluções de gerenciamento necessárias para melhorar e avaliar o desempenho de processos de TI. Especificamente, esta tese foca nos passos do processo que podem ser medidos através de observação ou intrumentação e que podem ser aprimorados através de projeto e automação. As soluções de gerenciamento introduzidas são investigadas através de um estudo de caso real, relacionado ao processo de Cumprimento de Requisição. O foco deste estudo de caso é nos operadores humanos com a responsabilidade de receber as requisições dos clientes e encaminhá-las paras administradores de sistema responsáveis por resolver as requisições. Neste contexto, os mashups são investigados como uma solução efetiva para lidar com ineficiências e erros introduzidos pelos operadores humanos enquanto executam suas atividades diárias relacionadas à gerência de serviços de TI. Foi realizada uma extensa investigação das tarefas realizadas por um grupo de especialistas em um centro global de suporte e entrega de serviços de TI. Os resultados demonstram a viabilidade da tecnologia de mashups como solução para aprimorar a gerência de serviços de TI. / Modern IT service provider organizations are under a continuous pressure to increase their competitiveness. Ways to reduce costs while improving performance – in terms of productivity and quality – of services are a key focus area for companies in the IT industry. However, despite all the solutions that have been proposed, modelling and optimizing human-centered processes remains a burdensome task. The human operator may be influenced by multiple factors and execute the process in a different way each time, thus introducing a significant variability in the final process outcome. Although the research proposed so far have introduced improvements on service management, there are several challenges (e.g., rapid change, budgetary constraints, skill shortages, system complexity, current and future user requirements, and growing user expectations) that are not completely covered by the current efforts. Among the new technologies available today, a set of novel ones, referred to as Web 2.0, has not yet been investigated by both industry and academia in the ITSM context. In the myriad of technologies and applications that define the Web 2.0, one is of special interest in this thesis: the mashups. Mashups are Web applications created through the composition of preexisting Web resources (e.g., interactive maps, Web services, traditional HTML pages, or even Flash presentations). Easiness of use, extensibility, and context specific development are examples of characteristics presented by mashups that candidate them to be a viable technology for improving IT Service Management. Therefore, the goal of this thesis is to investigate the feasibility of mashups as an effective approach to improve performance (i.e., in terms of productivity and reliability) of human-centered ITSM activities. In particular, this thesis aims to define management solutions required to deliver and demonstrate improvements in performance of humancentered ITSM processes. Specifically, the focus is on individual steps in the process that can be assessed through instrumentation or observation, and can be improved through design and automation. The analysis of exogenous events are not addressed, such as answering telephone calls or other interruptions. The introduced management solutions are examined through a real case study, related to the Request Fulfillment process. The focus of this case study is on dispatch, an activity centered on human operators called dispatchers, with knowledge of standard fulfillment procedures. In this context, mashups are analyzed as an effective approach to cope with inefficiencies and errors introduced by human operators while performing their daily activities in the context of ITSM. An extensive analysis of tasks performed by a group of Subject Matter Experts (SMEs) in a global IT Service Support and Delivery organization was performed. The results demonstrate the viability of the mashups technology as a means for improving IT Service Management.

[pt] Este trabalho apresenta modelo para avaliação quantitativa da confiabilidade de sistemas a partir do conhecimento das confiabilidades individuais dos componentes, sua configuração física e dos requisitos de desempenho do sistema. O modelo tem como base Diagramas Lógicos e caracteriza-se por ser versátil e de fácil aplicação em estudos de alternativas de projeto em qualquer especialidade de engenharia. Para implementação do modelo desenvolveu-se programa computacional de uso amigável com interface gráfica. São apresentados testes com sistemas realistas. / [en] This work presents a model for quantitative analysis of the systems reliability considering the knowledge of each component reliability and its physical configuration, as well as on the system performance requirements. This model is based on Logical Diagrams and distinguishes itself by its versatility and easiness of application in project alternative studies in any branch of engineering. In order to implement the model, we developed a user-friendly software with a graphic interface. Moreover, we present several tests with realistic systems.