Dissertations / Theses: 'Measures of central tendency'

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Aristodemou, Katerina. "New regression methods for measures of central tendency." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/9268.

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Measures of central tendency have been widely used for summarising statistical data, with the mean being the most popular summary statistic. However, in reallife applications it is not always the most representative measure of central location, especially when dealing with data which is skewed or contains outliers. Alternative statistics with less bias are the median and the mode. Median and quantile regression has been used in different fields to examine the effect of factors at different points of the distribution. Mode estimation, on the other hand, has found many applications in cases where the analysis focuses on obtaining information about the most typical value or pattern. This thesis demonstrates that mode also plays an important role in the analysis of big data, which is becoming increasingly important in many sectors of the global economy. However, mode regression has not been widely applied, even though there is a clear conceptual benefit, due to the computational and theoretical limitations of the existing estimators. Similarly, despite the popularity of the binary quantile regression model, computational straight forward estimation techniques do not exist. Driven by the demand for simple, well-found and easy to implement inference tools, this thesis develops a series of new regression methods for mode and binary quantile regression. Chapter 2 deals with mode regression methods from the Bayesian perspective and presents one parametric and two non-parametric methods of inference. Chapter 3 demonstrates a mode-based, fast pattern-identification method for big data and proposes the first fully parametric mode regression method, which effectively uncovers the dependency of typical patterns on a number of covariates. The proposed approach is demonstrated through the analysis of a decade-long dataset on the Body Mass Index and associated factors, taken from the Health Survey for England. Finally, Chapter 4 presents an alternative binary quantile regression approach, based on the nonlinear least asymmetric weighted squares, which can be implemented using standard statistical packages and guarantees a unique solution.

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Amiruzzaman, Md. "EXPLORING PRESERVICE TEACHERS' UNDERSTANDING OF MEASURES OF CENTRAL TENDENCY." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1478597164063024.

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Adams, Thomas Edwin III. "The Use of Central Tendency Measures from an Operational Short Lead-time Hydrologic Ensemble Forecast System for Real-time Forecasts." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/83461.

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A principal factor contributing to hydrologic prediction uncertainty is modeling error intro- duced by the measurement and prediction of precipitation. The research presented demon- strates the necessity for using probabilistic methods to quantify hydrologic forecast uncer- tainty due to the magnitude of precipitation errors. Significant improvements have been made in precipitation estimation that have lead to greatly improved hydrologic simulations. However, advancements in the prediction of future precipitation have been marginal. This research shows that gains in forecasted precipitation accuracy have not significantly improved hydrologic forecasting accuracy. The use of forecasted precipitation, referred to as quantita- tive precipitation forecast (QPF), in hydrologic forecasting remains commonplace. Non-zero QPF is shown to improve hydrologic forecasts, but QPF duration should be limited to 6 to 12 hours for flood forecasting, particularly for fast responding watersheds. Probabilistic hydrologic forecasting captures hydrologic forecast error introduced by QPF for all forecast durations. However, public acceptance of probabilistic hydrologic forecasts is problematic. Central tendency measures from a probabilistic hydrologic forecast, such as the ensemble median or mean, have the appearance of a single-valued deterministic forecast. The research presented shows that hydrologic ensemble median and mean forecasts of river stage have smaller forecast errors than current operational methods with forecast lead-time beginning at 36-hours for fast response basins. Overall, hydrologic ensemble median and mean forecasts display smaller forecast error than current operational forecasts.
Ph. D.

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Leite, Ana Paula Fernandes. "Estimativa de medidas de tendência central: uma intervenção de ensino." Pontifícia Universidade Católica de São Paulo, 2010. https://tede2.pucsp.br/handle/handle/11461.

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The objective of this study was to investigate the contributions of an educational intervention, based on the significance and estimate measures of central tendency, from reading charts and tables. In order to achieve this purpose, we elaborated a character study of quasi-experimental design which included two distinct groups of a public school in the state of São Paulo. The first group, called the experimental group(GE), composed of 30 students who underwent a differentiated education based on the significance and estimate measures of central tendency, and the second group, called the control group (GC), composed of 27 students who had their classes routine. Were applied to both groups a pre-test to diagnose the level of prior knowledge of students involved, and a post-test after the teaching interventions, to diagnose the effects of these interventions. The theoretical framework of the study included the Theory of Conceptual Fields of Gérard Vergnaud (1982, 1990, 1993, 1996, 1997 and 1998). We also have some related studies by authors such as Batanero et al. (1997), Cazorla (2003), Echeveste et al. (2006), Araujo (2007), Meyen et al. (2007), Silva (2008), Pagan (2009) and Magina et al. (in press). The study aimed to answer the following question: "What contributions in terms of learning, a teaching intervention guided the significance and estimate measures of central tendency, brings high school students?". To this end, has become based on quantitative analysis of the results obtained in the statistical tests applied to two groups involved in the study. The analysis showed a significant gain with the teaching interventions in both GE and CG, as regards the seizure of the basic concepts of mean, mode and median, but a significantly higher performance was presented by students in the experimental group after intervention education. The result showed that the learning process of statistical content, guided by the significance and estimation proved to be effective on the cognitive gain by students on information presented as graphs and tables, and also how to gain strength in regarding knowledge of the statistical study, more specifically, Mean, Mode and Median
O objetivo deste estudo foi investigar as contribuições de uma intervenção de ensino, pautada na significação e estimativa de Medidas de Tendência Central, com base na da leitura de gráficos e tabelas. A fim de atingir o objetivo proposto, elaborou-se um estudo de caráter do tipo quase-experimental que contou com dois grupos distintos de uma escola da rede pública estadual da cidade de São Paulo. O primeiro grupo, denominado Grupo Experimental, composto por 30 alunos que sofreu uma intervenção de ensino diferenciada, baseada na significação e estimativa de Medidas de Tendência Central, e o segundo grupo, denominado Grupo de Controle, composto por 27 alunos, que teve suas aulas rotineiras. Foram aplicados a ambos os grupos um pré-teste, a fim de diagnosticar o nível de conhecimento prévio dos alunos envolvidos, e um pós-teste, após as intervenções de ensino, visando a diagnosticar os efeitos dessas intervenções. O quadro teórico do estudo contou com a Teoria dos Campos Conceituais de Gérard Vergnaud (1982; 1990; 1993; 1996; 1997 e 1998). Contamos ainda com alguns estudos correlatos de autores como Batanero et al. (1997), Cazorla (2003), Echeveste et al. (2006), Araujo (2007), Meyén et al. (2007), Silva (2008), Pagan (2009) e Magina et al. (no prelo). O estudo propôs-se a responder à seguinte questão: Em termos de aprendizagem, quais as contribuições que uma intervenção de ensino pautada na significação e estimativa de Medidas de Tendência Central traz aos alunos do Ensino Médio? . Para tal, tomou-se por base a análise quantitativa dos resultados obtidos nos testes estatísticos aplicados aos dois grupos envolvidos no estudo. As análises apontaram um ganho significativo com as intervenções de ensino nos dois grupos GE e GC, no que diz respeito à apreensão de conceitos básicos sobre Média, Moda e Mediana, contudo um desempenho significativamente superior foi apresentado pelos alunos do grupo experimental, após a intervenção de ensino. O resultado permitiu inferir que o processo de aprendizagem de conteúdos de Estatística, pautado na significação e estimativa, mostrou-se eficaz quanto ao ganho cognitivo por parte dos alunos em informações apresentadas na forma de gráficos e tabelas, e, também, quanto ao ganho adquirido no que diz respeito ao conhecimento dos elementos estatísticos estudados, mais especificamente, Média, Moda e Mediana

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Lemos, Maria Patrícia Freitas de. "O desenvolvimento profissional de professores do 1º ao 5º ano do ensino fundamental em um processo de formação para o ensino e a aprendizagem das medidas de tendência central." Pontifícia Universidade Católica de São Paulo, 2011. https://tede2.pucsp.br/handle/handle/10879.

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The following review aims to investigate what comprehension and educational and didactical development of the content can be identified in teachers that operate in basic education from the first to the fifth school year on the Measures of Central Tendency, from the investigation of their professional development on a continuous graduation. For so, we structured the review in three theoretical moments that organise our bibliographical review: a review of the studies on Measures of Central Tendency that allowed us to identify the obstacles faced by the students and teachers, and a discussion about the teacher's professional development. The methodological process of the research was structured in five stages distributed as follows: the first stage is the settlement of a teaching sequence in a Statistics course arranged in five meetings; the second stage is the elaboration of a task; the third stage is the analysis of the task elaborated; the fourth stage is the implementation of the task in classroom; and the fifth stage is the completion of the analysis process and discussion about the implementation of the task in classroom and the whole process of intevention experienced. Six teachers who taught from the first to the fifth school year of the basic education in the city of São Paulo participated in this study in the period of the development of the project. The results showed that the initial difficulties identified in the protocols built with dialogues and productions of the teachers, in the comprehension of the concepts of median, mode and media and of their properties, were overcome during the process, though the global analysis showed graduation insufficiency to the achievement of this conceptual construction. With respect to the elaboration and analysis of the task, we realised that the teachers had trouble in enunciating the contents of median, mode and media, not identifying the properties, the kind of variant involved in the task and their influence in the development of the task in classroom. In the analysis of a task elaborated by them, the teachers also showed lack of articulation, master and knowledge of the content. The implementation of the task in classroom took place as a positive moment in which the teachers could see not only the good performance of the students, but also could reconsider their conceptions and attitudes towards the Statistics, which was reinforced in the stage destinated to the analysis and discussion about the whole process of intervention. We came to the realisation that the teachers could enlarge their professional development not only in what comes to the contents of the Measures of Central Tendency, but in their conceptions, attitudes and educational knowledge of the content, admitting their difficulties and realising the importance of a continuous graduation process
O presente estudo tem por objetivo investigar que compreensão e desenvolvimento pedagógico e didático do conteúdo podem ser identificados em professores que atuam no Ensino Fundamental, do 1º ao 5º ano, sobre as Medidas de Tendência Central, a partir da investigação de seu desenvolvimento profissional numa formação continuada. Para tanto, estruturamos o estudo em dois momentos teóricos que organizaram nossa revisão bibliográfica: uma revisão dos estudos sobre Medidas de Tendência Central, que nos permitiu identificar as dificuldades enfrentadas pelos alunos e professores, e uma discussão sobre o desenvolvimento profissional do professor. O processo metodológico da pesquisa foi estruturado em cinco etapas distribuídas da seguinte forma: primeira etapa: aplicação de uma sequência de ensino em um curso de Estatística organizado em cinco encontros; segunda etapa: elaboração de uma tarefa; terceira etapa: análise da tarefa elaborada; quarta etapa: aplicação da tarefa em sala de aula, e quinta etapa: realização do processo de análise e discussão da aplicação da tarefa em sala de aula e sobre todo o processo de intervenção vivenciado. Participaram deste estudo seis professoras que lecionavam do 1º ao 5º ano do Ensino Fundamental na cidade de São Paulo, no período de desenvolvimento do projeto. Os resultados mostraram que as dificuldades iniciais identificadas nos protocolos construídos com diálogos e produções das professoras, na compreensão dos conceitos de média, moda e mediana e de suas propriedades, foram sendo superadas ao longo do processo, embora a análise global tenha mostrado a insuficiência da formação para a consolidação dessa construção conceitual. Em relação à elaboração e análise da tarefa, percebemos que as professoras tiveram dificuldades em articular os conteúdos de média, moda e mediana, não identificando as propriedades, o tipo de variável envolvida na tarefa e a influência destes no desenvolvimento da tarefa em sala de aula. Na análise de uma tarefa elaborada por elas, as professoras também demonstraram a falta de articulação, domínio e conhecimento do conteúdo. A aplicação dessa tarefa em sala de aula se configurou como um momento positivo em que as professoras puderam observar não apenas o bom desempenho dos alunos, mas repensaram em suas concepções e atitudes em relação à estatística, o que foi reforçado na etapa destinada à análise e discussão de todo o processo de intervenção. Pudemos constatar que as professoras conseguiram ampliar seu desenvolvimento profissional não apenas em relação aos conteúdos das medidas de tendência central, mas nas concepções, atitudes e conhecimento didático do conteúdo, assumindo suas dificuldades e percebendo a importância de um processo contínuo de formação

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Vargas, Glaucia Garcia Bandeira de. "A METODOLOGIA DA RESOLUÇÃO DE PROBLEMAS E O ENSINO DE ESTATÍSTICA NO NONO ANO DO ENSINO FUNDAMENTAL." Universidade Franciscana, 2013. http://tede.universidadefranciscana.edu.br:8080/handle/UFN-BDTD/134.

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This paper, developed in the Physics and Mathematics Master‟s degree at Centro Universitário Franciscano UNIFRA, has the objective of investigating the Methodology of Problem-solving in the Statistics teaching for the students at the ninth grade of the elementary school. The starting point is the certification that Statistics is normally put in second place in a classroom, despite being recommended by the National Curricular Parameters (PCNs). Besides that, it has been proved effective as a tool of reality comprehension, critical spirit development and, also, having an interdisciplinary role. The research, developed with the students at the ninth grade of a public school in Santa Maria, RS, Brazil, used the methodology of qualitative approach and the Problem-solving method proposed by Onuchic e Allevato (2009). In six meetings of two hours each, some charts concepts, graphics and Measures of central tendency (mean, median and mode) were used from the applied problems based in nine steps defined by the authors. The raw-material of the problems were socioeconomic data of the students‟ family obtained from a questionnaire inspired in 2010 Census of the Brazilian Institute of Geography and Statistics (IBGE). This way, it was aimed to apply statistical knowledge to the students‟ reality. The work development confirmed the premise that the statistics is not appreciated during the elementary school, as at the last year of this phase, the students show elementary difficulties in tasks like reading statistical data, creating graphics from charts and elaborate conclusions and comparisons of data statistically exposed. This unawareness, caused by the absence of the subject in the class program, is partly compensated by the fact of statistics being present in the students‟ routine, by the press and other social segment. Fortunately, it was possible to consolidate with the students some knowledge about basic concepts, capacity of data reading and charts construction and also statistical concept understanding. This start point has shown, during this work, a base which it is possible to construct a more elaborated knowledge. In this sense, two factors contributed: 1) the application of problem-solving methodology for statistics, creating an environment of curiosity for some students, who felt challenged to overcome the obstacles proposed in the problems; 2) the adoption of raw material excerpted from the students‟ reality (questionnaire responses with socioeconomics data from their families and Census 2010 official figures) to construct the problem-situations which were the base to the work development. At the end of the meetings, it was possible to identify that the students had a progress in their knowledge about statistics, borrow some concepts and realized how valuable those concepts were as a tool of reading and reality comprehension, which is a crucial start point for the adoption of an attitude that seeks social and economics transformations which can be positive in the lives of the students and their families.
Este estudo, desenvolvido no Mestrado Profissionalizante em Ensino de Física e de Matemática do Centro Universitário Franciscano UNIFRA, tem por objetivo investigar a contribuição da Metodologia de Resolução de Problemas no ensino de Estatística para alunos do nono ano do Ensino Fundamental. O ponto de partida é a constatação de que a Estatística costuma ser colocada em segundo plano em sala de aula, embora seja recomendada pelos Parâmetros Curriculares Nacionais (PCNs), além de ser comprovadamente eficaz como ferramenta de compreensão da realidade, desenvolvimento do espírito crítico e cidadão e, ainda, tenha um papel interdisciplinar. A pesquisa, desenvolvida com alunos do nono ano de uma escola pública de Santa Maria (RS), utilizou a metodologia de pesquisa de abordagem qualitativa e a Metodologia de Ensino de Resolução de Problemas proposta por Onuchic e Allevato (2009). Em seis encontros de duas horas cada foram trabalhados os conceitos de tabelas, gráficos e medidas de tendência central (média, moda e mediana), a partir de problemas aplicados com base em nove passos definidos pelas autoras. A matéria-prima dos problemas foram dados socioeconômicos das famílias dos próprios alunos, obtidos a partir de um questionário inspirado no Censo 2010 do Instituto Brasileiro de Geografia e Estatística (IBGE). Dessa forma, objetivou-se aplicar conhecimentos estatísticos à realidade dos alunos. O desenvolvimento do trabalho confirmou a premissa de que a Estatística é pouco valorizada ao longo do Ensino Fundamental, já que no ano final desta fase os alunos demonstraram dificuldades elementares em tarefas como ler dados estatísticos, construir gráficos a partir de tabelas e elaborar conclusões e comparações de dados expostos estatisticamente. Este desconhecimento, causado pela ausência do tema dos programas de aula, em parte é compensada pelo fato de a estatística estar muito presente no dia a dia dos alunos, pela imprensa e outros segmentos sociais. Graças a isso, foi possível consolidar junto com os alunos conhecimentos sobre conceitos básicos, capacidade de leitura de dados, de construção de gráficos e de entendimento de conceitos estatísticos. Este ponto de partida se revelou, ao longo do trabalho, uma base sobre a qual é possível construir um conhecimento mais elaborado. Contribuíram neste sentido dois fatores: 1) a utilização da metodologia de resolução de problemas aplicada à estatística, gerando um ambiente de curiosidade de parte dos alunos que se sentiram desafiados a superar os obstáculos propostos nos problemas; 2) a adoção de matéria-prima extraída da realidade dos alunos (respostas de questionário com dados socioeconômicos de suas famílias e dados oficiais do Censo 2010) para construir as situações-problema que deram base ao desenvolvimento do trabalho. Ao final dos encontros, foi possível identificar que os alunos evoluíram no conhecimento sobre Estatística, apropriaram-se de conceitos e perceberam o inestimável valor deles como ferramenta de leitura e compreensão da realidade, o que é um ponto de partida decisivo para a adoção de uma postura que busque transformações sociais e econômicas positivas na vida dos alunos e de seus familiares.

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Araújo, José Ronaldo Alves. "Atividades para o estudo das Medidas de Tendência Central: uma proposta com o apoio do GeoGebra." Pontifícia Universidade Católica de São Paulo, 2018. https://tede2.pucsp.br/handle/handle/21308.

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This dissertation presents a qualitative investigation which was carried out within thscope of Statistics teaching and lasted for the potentialities of GeoGebra for an understanding of the Meditation of Central Tendency concepts. Based on the didactic actions, the formulation, validation and institutionalization of the Theory of Didactic Situations, the search was developed through a sequence of activities. The methodological methods for the elaboration, application and analysis of the activities were realized by the Engineering dimensions as preliminary techniques such as a priori analysis, experiment and a posteriori analysis. The participants in the research program was a high school group of the 1st grade in a public school in the state of São Paulo. The application of the class was carried out in a computer lab of the same school and was divided by four sessions of five minutes. The participants, through GeoGebra, treated the data of each activity and were answering the questions of the present study. Ahead of questions and answers, it was possible to identify, from the dialectical practices of the theoretical, the potentialities of GeoGebra for an understanding of the proposed mathematical objectives, such as, in a dialectic of action, the organization of the data and the search for answers to some questions. This organization of the data in tables, lists, ordered lists, graphical representation or even values for the Central Administration classes allows the students, a formulation dialectic, to reflect on the representation of the values in relation to the data set. The various representations of the data in the GeoGebra windows, in a validation dialectic, favor the participation of the participants on the relation of the indicators with the data of their origin. These multiple representations of a set of data allow other questions, allowing the discussion on market conditions, such as the evaluation of trends, which contributed to the teacher, a dialectic of institutionalization with the students, would be able to promote of consolidation of knowledge
Esta dissertação apresenta uma investigação de caráter qualitativo, realizada no âmbito do ensino da Estatística, e teve como objetivo identificar potencialidades do GeoGebra para a compreensão dos conceitos de Medidas de Tendência Central. Com base nas dialéticas de ação, formulação, validação e institucionalização da Teoria das Situações Didáticas, a pesquisa foi desenvolvida por meio de uma sequência de atividades. Os procedimentos metodológicos para elaboração, aplicação e análise das atividades utilizaram aspectos da Engenharia Didática com as análises preliminares, análises a priori, experimento e análises a posteriori. Participaram desta pesquisa alunos da 1ª série do ensino médio de uma escola da rede pública do estado de São Paulo. A aplicação da proposta ocorreu no laboratório de informática da mesma escola, em quatro sessões de cinquenta minutos e os participantes, por meio do GeoGebra, trataram os dados de cada atividade e responderam aos questionamentos do estudo. Diante dos questionamentos e das respostas apresentadas, foi possível identificar, a partir das dialéticas do aporte teórico, potencialidades do GeoGebra para a compreensão dos objetos matemáticos propostos, tais como, em uma dialética de ação, organizar os dados e encontrar respostas para alguns questionamentos. Essa organização dos dados em tabelas, listas, listas ordenadas, representação gráfica ou mesmo valores para as Medidas de Tendência Central permitiu aos alunos, em uma dialética de formulação, refletirem sobre a representação dos valores em relação ao conjunto de dados. As múltiplas representações dos dados nas janelas do GeoGebra, em uma dialética de validação, favoreceram para que os participantes conjecturassem sobre a relação dos valores encontrados com os dados de sua origem. Essas múltiplas representações de um mesmo conjunto de dados permitiram outros questionamentos, possibilitando discussões acerca de possíveis propriedades para as Medidas de Tendência Central, o que contribuiu para que o professor, em uma dialética de institucionalização junto aos alunos, promovesse a consolidação do saber

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Lira, Veras Xavier de Andrade Vladimir. "Os conceitos de medidas de tendência central e de dispersão na formação estatística no ensino médio no Brasil e na França.- Abordagem exploratória no quadro da teoria antropológica do didático e da teoria dos campos conceituais." Thesis, Lyon 2, 2013. http://www.theses.fr/2013LYO20071/document.

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La statistique est d’une grande importance pour l’éducation scientifique et citoyenne, et a été adoptée pour cette raison dans les programmes des collèges et lycées dans plusieurs pays, parmi lesquels le Brésil et la France. Les mesures de tendance centrale et les mesures de dispersion sont deux concepts fondamentaux de la statistique descriptive. À partir des problèmes identifiés dans différentes recherches sur l’apprentissage des mesures de tendance centrale et de dispersion dans l’enseignement secondaire et supérieur, nous formulons l’hypothèse qu’il existe une relation entre ces problèmes d’apprentissage et la façon dont ce savoir est transposé dans les manuels et les programmes. Nous considérons également que ces mesures doivent être enseignées en articulation avec la dispersion. Dans ce sens, cette étude se propose d’analyser la façon dont les mesures de tendance centrale et de dispersion sont présentées dans les programmes et dans certains manuels scolaires utilisés dans les lycées Brésiliens et Français. L’objet principal de cette recherche a donc été la réalisation d’une recherche bibliographique. Cette étude s’appuie sur un ensemble de recherches et de théories, et en particulier sur la théorie anthropologique de la didactique et la théorie des champs conceptuels. Les résultats produits incluent une proposition de systématisation de notre recherche de thèse, un chapitre sur le savoir scientifique relatif aux mesures de tendance centrale et de dispersion ainsi que l’analyse de la transposition didactique des programmes et des manuels scolaires qui comportent une discussion sur les caractéristiques de ces éléments au Brésil et en France. Les résultats indiquent des limitations parmi les programmes et les manuels scolaires sélectionnés, ce qui peut indiquer que les problèmes mis en évidence dans les recherches étudiées sont en partie liés à la façon dont cette connaissance est transposée dans les programmes et les manuels scolaires
The statistic has a great importance in the scientific and civic education, and was adopted for this reason in the programs of middle and high schools in several countries, among which Brazil and France. Central tendency measures and dispersion measures are two fundamental concepts for descriptive statistic. From the problems identified in various researches about learning central tendencies and dispersion in secondary and higher education, we hypothesize that there is a relation between these learning problems and the way this knowledge is transposed in handbooks and school programs. We also consider that these measures must be taught articulated with dispersion. In that sense, this study offers to analyze how central tendency and dispersion measures are presented in some programs and handbooks used in Brazilian and French high schools. The main objet of this research was the realization of a bibliographical research. This study is built on various theories and researches and in particular the anthropological theory of didactics and the theory of conceptual fields. The results produced include the proper proposition of systematization of the thesis research, a chapter about the scientific knowledge related to central tendency measures and dispersion measures as well as the analysis of didactic transposition of the programs and scholar handbooks that include a discussion about the characteristics of these elements in France and Brazil. The results show limitations among the selected handbooks and programs, which points out the problems highlighted in the studies are partly linked to how this knowledge is transposed in programs and handbooks
A Estatística é importante para a educação científica e cidadã e por esta razão ela é adotada nos programas do ensino fundamental e médio de vários países, entre eles, o Brasil e a França. Dois conceitos fundamentais da estatística descritiva são as medidas de tendência central e dispersão. Partindo de problemas identificados em diversas pesquisas sobre a aprendizagem dessas medidas na educação básica e em cursos de graduação, propomos como hipótese que existe uma relação entre esses problemas e a forma como esse saber é transposto para o livro didático e os programas. Consideramos também que essas medidas devem ser ensinadas de forma articuladas com a dispersão. Nesse sentido, este estudo tem por objetivo a análise da forma como as medidas de tendência central e dispersão são apresentadas nos programas e em alguns livros didáticos utilizados no Brasil e na França no ensino médio. Para esta investigação, realizamos uma pesquisa bibliográfica. Apoiamos este estudo em diversos teóricos e pesquisas. Destacando em especial a teoria antropológica do didático e a teoria dos campos conceituais. Entre os resultados produzidos, temos a própria proposta de sistematização da pesquisa pela tese, um capítulo sobre o saber científico relativo às medidas de tendência central e dispersão e a análise da transposição didática dos programas e dos livros que envolvem uma discussão sobre as características destes elementos no Brasil e na França. Os resultados indicam limitações entre os programas e livros selecionados, o que pode indicar que em parte os problemas indicados, nas pesquisas levantadas, estão relacionados à forma como esse conhecimento é transposto nos programas e livros didáticos

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Estelle, Dawn N. "Central auditory processing disorders Outcome Measures /." Cincinnati, Ohio : University of Cincinnati, 2005. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1121349085.

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Thesis (M.A.)--University of Cincinnati, 2005.
Title from electronic thesis title page (viewed Mar. 3, 2006). Includes abstract. Keywords: Central Auditory Processing Disorders. Includes bibliographical references.

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ESTELLE, DAWN N. "CENTRAL AUDITORY PROCESSING DISORDERS: OUTCOME MEASURES." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1121349085.

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Yarlagadda, Phani Srinivas. "Central-tendency estimation and nearest-estimate classification of multi-channel evoked potentials /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1967802721&sid=3&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Yarlagadda, Phani Srinivas Prasad. "Central-Tendency Estimation and Nearest-Estimate Classification of Multi-Channel Evoked Potentials." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/148.

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By modeling evoked potentials (EPs) as random vectors in which the EP samples are random variables, a unified strategy is introduced to determine multivariate central-tendency estimates such as the arithmetic mean, geometric mean, harmonic mean, median, tri-mean, trimmed-mean, and the Winsorized mean. Additionally, a generalized strategy is introduced to develop minimum-distance classifiers based on central-tendency estimates. Furthermore, procedures are developed to fuse the decisions of the resulting nearest-estimate classifiers for single-channel heterogeneous, multi-channel homogeneous, and multichannel heterogeneous-homogenous EP classification. The central-tendency estimates of real EPs are compared and it is shown that although the operations to compute the vector central-tendency estimates can be quite different, the EP estimates are similar with respect to their overall waveform shapes and peak latencies. It is also shown that by fusing homogeneous nearest-estimate classifier decisions across multiple channels, the classification accuracy can be improved significantly when compared with the accuracies of individual channel classifiers.

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Snowden, Jessica L. "Explicit and implicit bias measures : their relation and utility as predictors of criminal verdict tendency /." Electronic version (PDF), 2005. http://dl.uncw.edu/etd/2005/snowdenj/jessicasnowden.pdf.

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Ahn, Jae Youn. "Non-parametric inference of risk measures." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/2808.

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Responding to the changes in the insurance environment of the past decade, insurance regulators globally have been revamping the valuation and capital regulations. This thesis is concerned with the design and analysis of statistical inference procedures that are used to implement these new and upcoming insurance regulations, and their analysis in a more general setting toward lending further insights into their performance in practical situations. The quantitative measure of risk that is used in these new and upcoming regulations is the risk measure known as the Tail Value-at-Risk (T-VaR). In implementing these regulations, insurance companies often have to estimate the T-VaR of product portfolios from the output of a simulation of its cash flows. The distributions for the underlying economic variables are either estimated or prescribed by regulations. In this situation the computational complexity of estimating the T-VaR arises due to the complexity in determining the portfolio cash flows for a given realization of economic variables. A technique that has proved promising in such settings is that of importance sampling. While the asymptotic behavior of the natural non-parametric estimator of T-VaR under importance sampling has been conjectured, the literature has lacked an honest result. The main goal of the first part of the thesis is to give a precise weak convergence result describing the asymptotic behavior of this estimator under importance sampling. Our method also establishes such a result for the natural non-parametric estimator for the Value-at-Risk, another popular risk measure, under weaker assumptions than those used in the literature. We also report on a simulation study conducted to examine the quality of these asymptotic approximations in small samples. The Haezendonck-Goovaerts class of risk measures corresponds to a premium principle that is a multiplicative analog of the zero utility principle, and is thus of significant academic interest. From a practical point of view our interest in this class of risk measures arose primarily from the fact that the T-VaR is, in a sense, a minimal member of the class. Hence, a study of the natural non-parametric estimator for these risk measures will lend further insights into the statistical inference for the T-VaR. Analysis of the asymptotic behavior of the generalized estimator has proved elusive, largely due to the fact that, unlike the T-VaR, it lacks a closed form expression. Our main goal in the second part of this thesis is to study the asymptotic behavior of this estimator. In order to conduct a simulation study, we needed an efficient algorithm to compute the Haezendonck-Goovaerts risk measure with precise error bounds. The lack of such an algorithm has clearly been noticed in the literature, and has impeded the quality of simulation results. In this part we also design and analyze an algorithm for computing these risk measures. In the process of doing we also derive some fundamental bounds on the solutions to the optimization problem underlying these risk measures. We also have implemented our algorithm on the R software environment, and included its source code in the Appendix.

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Kelly, Andrea Susan. "Electrophysiological and behavioural measures of central auditory processing in adult cochlear implant users." Thesis, University of Auckland, 2001. http://hdl.handle.net/2292/3126.

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This study aimed to determine the relationship between auditory evoked potential measures, speech perception and frequency discrimination in 12 experienced adult cochlear implant (CI) users and to compare the evoked potential results in the CI subjects to those of a group of age- and gender-matched control subjects with normal hearing. The CI subjects all used the Nucleus CI-22 implant with the SPEAK processing strategy. Subject age range was 27-74 years (mean 50.9 years). All had used their implant for a minimum of one year (range 13-76 months, mean duration of implant use 37.5 months).Duration of profound deafness prior to implantation ranged from 1 - 40 years (mean 15.6 years).Middle latency response (MLR), obligatory N1-P2 cortical potentials, mismatch negativity and P3a auditory evoked potential were recorded. Speech perception was evaluated using tests from "The Minimum Speech Test Battery for Adult Cochlear Implant Users". Frequency discrimination was measured using a two-alternative forced choice procedure, to record difference limens (DL) for a 1000Hz tone. Duration of deafness correlated strongly with speech perception scores with poor scores reflecting greater years of deafness. The most sensitive of all the evoked potential measures was P2 latency, with strong relationships found between P2 and duration of deafness and speech perception scores. Earlier P2 latencies were associated with shorter durations of deafness and higher speech perception scores. In general, mismatch negativity was absent or degraded in CI subjects with poor speech scores. In better implant users mismatch negativity was typically present to both large and small frequency differences and demonstrated characteristic changes of increased latency and decreased area and amplitude for the more difficult discrimination task (as seen in the normal hearing group). Na amplitude of the MLR correlated negatively with duration of deafness, with small amplitudes reflecting greater duration of deafness. Frequency DLs were very variable, and no strong relationships were found between these and the evoked potential or speech perception measures.

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Fink, Gerhard. "New protectionism in Central Europe. Exchange rate adjustment, customs tariffs and non-tariff measures." Forschungsinstitut für Europafragen, WU Vienna University of Economics and Business, 1999. http://epub.wu.ac.at/970/1/document.pdf.

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Many of the 10 Central European candidate member countries for EU accession entered into the transition period with strongly undervalued exchange rates to stimulate exports and protect domestic industries. However, this policy was not maintained. During 1993-1995 real currency appreciation increased competitive pressure by foreign firms. To protect domestic firms governments applied high third country tariffs, temporary import taxes, and numerous administrative barriers to trade. As countervailing pressure by the EU and the USA increased and current account deficits soared in 1996 and 1997, the CE-10 more and more brought exchange rate policies in line with the changes in purchasing power parity. However, petty protection and harassment of importers prevails. (author's abstract)
Series: EI Working Papers / Europainstitut

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Kim, Dan. "Dynamic Encoding Is Neither Necessary Nor Sufficient For Logarithmic Compression In Number Estimation." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437057644.

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Yamagiwa, Takayoshi Jose. "An Assessment of Technical Barriers in Central American Agricultural and Food Trade." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/27494.

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This dissertation explores technical regulations (sanitary and phytosanitary (SPS) measures, technical barriers to trade, and geographical indications) in Central American agricultural and food trade. In the first part, a framework to systematically evaluate the broad issues for developing countries is presented. Evaluation of the issues for Central America is based on interviews with about 100 persons in the region and in the United States (US), and on secondary sources. The topic is of significance in Central America, especially when related to SPS measures. The World Trade Organization (WTO) Agreements have had relatively little direct impact in improving Central Americaâ s response to technical regulations, while homologous Central American regional institutions may have been more successful, with indirect support from the WTO and the US, in reducing the incidence of illegitimate regulations in intra-regional trade. Central America may implement illegitimate barriers more against others in the region than against the US. Although the Central America Free Trade Agreement (CAFTA) may support Central Americaâ s capacity to meet more stringent technical regulations, the improvement may not be sufficiently perceptible. The potential for Central American greenhouse tomato exports to the US is analytically evaluated in the second part. These tomatoes may be admitted as the ban based on the risk of introduction of the Mediterranean fruit fly is partially lifted, due in part on discussions in the CAFTA negotiations. Mature green, vine-ripe and greenhouse tomatoes are heterogeneous in demand, and vine-ripe tomatoes are but greenhouse tomatoes are not heterogeneous by origin. A static partial equilibrium model is constructed for the US tomato market, where demand is based on multi-stage budgeting and supply is a function of own tomato price. When the Central American greenhouse excess supply function is introduced to the model, the region exports to the US, the aggregate greenhouse quantity increases, and its prices decrease. As greenhouse preference increases, greenhouse quantity and prices also increase. Changes are perceptible but small in the mature green and vine-ripe markets in the expected direction. Access by Central America is particularly beneficial when US consumer preferences shift further toward greenhouse over other tomatoes.
Ph. D.

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Criss, Cody R. "Central Nervous System Contributions to Subjective and Objective Measures of Function after Anterior Cruciate Ligament Reconstruction." Ohio University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1617279837916864.

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20

Pradhan, Amynah Amir Ali. "Dissociation between behavioural and biochemical measures of mu and delta opioid receptors in rat central nervous system." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85954.

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The opioid receptor family is comprised of three members: mu, delta and kappa, all of which are G protein coupled receptors, primarily acting through Galphai/o subunits. Clinically, mu opioid receptor (MOR) agonists are used in the treatment of moderate to severe pain. delta opioid receptor (DOR) agonists are being developed as alternative analgesics, since stimulation of this receptor results in fewer adverse side effects. Characterization of behaviourally relevant mu and delta opioid receptors, as well as interactions between them, will provide a better understanding of opioid agonist-induced analgesia.
Although the behavioural knockdown after antisense targeting of MOR has been well characterized, few studies have examined the corresponding in vitro changes. Thus, the first aim of this thesis was to determine the neuroanatomical extent of MOR knockdown after pretreatment with peptide nucleic acid antisense in rats. Antisense pretreatment completely inhibited antinociception by the mu agonist DAMGO, but produced no detectable ex vivo changes in brain or spinal MOR labelling or functional responses. This study suggests that there may be a small, critical population of MORs that mediate antinociceptive responses to agonist.
The second aim of this thesis was to compare the CNS distribution of functional DOR with radioligand binding. DOR labelling was determined autoradiographically using an agonist, ([125I]deltorphin II) and an antagonist ([ 125I]AR-M100613) radioligand. In adjacent tissue sections, functional DORs were detected using deltorphin II-induced [35S]GTPgammaS binding. Overall, radioligand binding did not strongly predict the magnitude of [35S]GTPgammaS responses, and this weak association is possibly explained by a paucity of DORs on the cell surface and/or heterogeneity in G protein receptor coupling. The highest [35S]GTPgammaS responses were found in the basal ganglia, while areas involved with pain perception (spinal cord, brain stem, and periaqueductal grey) possessed low [35S]GTPgammaS responses.
The low deltorphin II-induced [35S]GTPgammaS binding in pain-related areas could explain the moderate degree of antinociception produced by delta agonists relative to their mu counterparts. Thus, the third aim of this thesis was to investigate two pharmacological treatments (short- and long-term morphine pretreatment) that are reported to enhance behavioural responses to delta agonists. As previously observed by others, short-term exposure to morphine resulted in sensitization to spinally administered delta agonists. In contrast, long-term morphine pretreatment resulted in profound tolerance to the antinociceptive and locomotor stimulant effects of deltorphin II. After chronic morphine pretreatment, there was no detectable change in DOR labelling or [35S]GTPgammaS responses in the brain or spinal cord, suggesting that changes in downstream regulators may be responsible for this tolerance.

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Scheperle, Rachel Anna. "Relationships among peripheral and central electrophysiological measures of spatial / spectral resolution and speech perception in cochlear implant users." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/5055.

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The ability to perceive speech is related to the listener's ability to differentiate among frequencies (i.e. spectral resolution). Cochlear implant users exhibit variable speech perception and spectral resolution abilities, which can be attributed at least in part to electrode interactions at the periphery (i.e. spatial resolution). However, electrophysiological measures of peripheral spatial resolution have not been found to correlate with speech perception. The purpose of this study was to systematically evaluate auditory processing from the periphery to the cortex using both simple and spectrally complex stimuli in order to better understanding the underlying processes affecting spatial and spectral resolution and speech perception. Eleven adult cochlear implant users participated in this study. Peripheral spatial resolution was assessed using the electrically evoked compound action potential (ECAP) to measure channel interaction functions for thirteen probe electrodes. We evaluated central processing using the auditory change complex (ACC), a cortical response, elicited with both spatial (electrode pairs) and spectral (rippled noise) stimulus changes. Speech perception included a vowel-discrimination task and the BKB-SIN test of keyword recognition in noise. We varied the likelihood of electrode interactions within each participant by creating three experimental programs, or MAPs, using a subset of seven electrodes and varying the spacing between activated electrodes. Linear mixed model analysis was used to account for repeated measures within an individual, allowing for a within-subject interpretation. We also performed regression analysis to evaluate the relationships across participants. Both peripheral and central processing abilities contributed to the variability in performance observed across CI users. The spectral ACC was the strongest predictor of speech perception abilities across participants. When spatial resolution was varied within a person, all electrophysiological measures were significantly correlated with each other and with speech perception. However, the ECAP measures were the best single predictor of speech perception for the within-subject analysis, followed by the spectral ACC. Our results indicate that electrophysiological measures of spatial and spectral resolution can provide valuable information about perception. All three of the electrophysiological measures used in this study, including the ECAP channel interaction functions, demonstrated potential for clinical utility.

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Whiton, Tara K. "The Influence of Chronic Branched-Chain Amino Acid Supplementation on Measures of Central and Peripheral Fatigue in Training Athletes." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3632.

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Branched-chain amino acid (BCAA) supplementation may improve recovery from competitive endurance training by reducing symptoms of central and peripheral fatigue. The purpose of this dissertation was to provide evidence for the use of BCAAs as a training nutrition strategy in order to improve recovery from training and further drive adaptive processes to training by increasing readiness to train. Collegiate distance runners undergoing intense competitive endurance training were monitored for symptoms of muscular soreness and psychological stress through a rated soreness chart and the Daily Analysis of Life Demands for Athletes Survey (DALDA) while taking either a BCAA supplement or a placebo. When on the BCAA supplement, athletes reported significantly fewer symptoms of psychological stress and reduced muscular soreness. These results point to the importance of nutrient bioavailability, specifically BCAAs, on recovery parameters when undergoing intensive training. This concept was also demonstrated in a case study on a trained distance runner who underwent intensive training for an ultra-endurance marathon. Running kinematics were assessed using Kinovea open-sourced software (Version 0.8.15) during a series of constant-paced endurance runs while on the BCAA supplement or a placebo. We observed a reduction in vertical oscillation when the runner was on the BCAA supplement, indicating improved muscle recovery and therefore efficiency of movement. Improving recovery by reducing global central and peripheral fatigue symptoms may increase readiness to train and further promote desired training adaptations.

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Eley, Devon M. "Neuromuscular Measures in Female Patients with Knee Osteoarthritis: A Pilot Study." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1430412150.

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Rocha, Joás Elias dos Santos. "Medidas de máxima entropia para difeomorfismos parcialmente hiperbólicos com folheação central compacta em T3." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/55/55135/tde-30072018-114107/.

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Este trabalho trata das medidas de máxima entropia para certos difeomorfismos em nilvariedades. Considere um difeomorfismo parcialmente hiperbólico f definido em T3, dinamicamente coerente com folheação central compacta. Suponha ainda que a aplicação induzida por f no espaço das folhas centrais é um homeomorfismo de Anosov transitivo em T2. Mostramos que o conjunto das medidas ergódicas hiperbólicas de máxima entropia é enumerável. Usando o princípio de invariância, mostramos que se o primeiro retorno de f à alguma folha periódica tem número de rotação irracional, então, f tem no máximo duas medidas ergódicas de máxima entropia e ter apenas uma medida de máxima entropia equivale a ser extensão de rotação. Se a aplicação de primeiro retorno à alguma folha central periódica é Morse-Smale, então existe um su-toro periódico, ou temos uma cota superior para o número de medidas ergódicas de máxima entropia que depende do número de atratores da dinâmica nessa folha. Além disso, estudamos a topologia da bacia das medidas ergódicas de máxima entropia para uma outra classe de difeomorfismos especiais que são genéricos no espaço dos difeomorfismos absolutamente parcialmente hiperbólicos e denotada por SPH1(M).
This work is about maximal entropy measures for certain diffeomorphisms on nilmanifolds. Consider a partially hyperbolic diffeomorphism f on T3 , C2 , dinamically coherent with compact center foliation which is a circle bundle. Assume that the map induced by f on the space of center leaves is a transitive Anosov homeomorphism. We show that the set of hyperbolic ergodic maximal entropy measures of f is countable. Using the invariance principle, we show that if the first return map to some periodic leaf has irrational rotation number then f has at most two ergodic maximal entropy measures and, in this case, if f has only one maximal entropy measure then f is a rotation extension. If the first return map to some periodic leaf is Morse-Smale then either there exists some periodic su-torus or an upper bound for the number of ergodic maximal entropy measure depending on the number of the attractors of the dynamics in this leaf. Moreover, we study the topology of basin of ergodic maximal entropy measures of another set of special diffeomorphisms that are generic in the space of absolutely partially hyperbolic systems and denoted by SPH1(M).

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MANTRI, ANUPAMA. "A GIS Based Approach to Measure Walkability of a Neighborhood." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1205012111.

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Harvey, Sarah L. "Recovery Measures for the State Endangered American Marten: An Internship with Two Wisconsin Natural Resource Agencies." Miami University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=miami1105225283.

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Nkhebenyane, Jane Sebolelo. "Microbial hazards associated with food preparation in Central South African HIV/Aids hospices." Thesis, Bloemfontein : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/135.

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Thesis (M. Tech.) -- Central University of Technology, Free State, 2010
South Africa currently faces one of the highest HIV prevalence rates in the world. As this prevalence rises, the strain placed on its hospitals is likely to increase due to the shortage of beds. The devastating effects of HIV/AIDS initiated the establishment of a hospice which is a non-governmental organisation whose goal is the provision of care for terminally ill patients, either in their homes, in hospitals or in a hospice’s own in-patients wards. Part of the hospice’s mission is to offer palliative care without charge to anyone who requires it. The basic elements of hospice care include pain and symptom management, provision of support to the bereaving family and promoting a peaceful and dignified death. This also includes the provision of cooked foods to the patients using the kitchen facilities of the hospices for this activity. It is well known that the kitchen is particularly important in the spread of infectious disease in the domestic environment due to many activities that occur in this particular setting. Food and water safety is especially important to the persons infected with the human immunodeficiency virus (HIV) or with immunodeficiency syndrome (AIDS).It is estimated that food-borne pathogens (disease–causing agents) are responsible for 76 million illnesses, some resulting in death, in the United States alone every year. In one study of patients with AIDS, two-thirds had diarrhoeal disease and in two-thirds of these, the following enteric pathogens were identified: Salmonella, Shigella, Listeria, Yersnia, Cryptosporidium, Entamoeba histolylica and Campylobacter sp. In an epidemiological study of patients with HIV infection a close association was found between consumption of raw or partially cooked fish and antimicrobial-resistant Mycobacterium avium complex. Antibiotic resistance in food-borne pathogens has become a reality and this poses a serious threat to the medical fraternity since it diminishes the effectiveness of treatment. This study was undertaken to determine the prevalence of foodborne pathogens including bio aerosols isolated from the kitchen surfaces and food handler’s before and after cooking. The antibiotic resistance of the isolated pathogens was further determined to assess their impact on treatment. The following microbiota were isolated: Total viable counts (TVC), Coliforms, Escherichia coli, Staphylococcus aureus, Pseudomonas and presumptive Salmonella. The hospices had high counts of E.coli and S.aureus on the cutting boards for the breakfast session compared to the traditional home based kitchens. It was speculated that this could have originated from crosscontamination via the foodhandler’s hands and the food served. It is evident from the results that hospices lack a management system regarding the prevalence of E. coli as it was present on the cutting boards throughout the food preparation sessions. Gram negative organisms (coliform and P. aeruginosa) were in particular both resistant to oxacillin and this pose a great challenge in this particular setting. This can be addressed by putting emphasis on hygiene as a strategy per se for reducing antibiotic resistance.

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De, Bruyn Daniel Nicholas. "Investigation and development of a system for secure synchronisation in a wireless mesh network." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2010. http://hdl.handle.net/11462/132.

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Thesis (M. Tech.(Electrical Engineering)) -- Central University of technology, Free State, 2010
This dissertation gives an overview of the research done in developing a protocol to synchronise information in a secure wireless mesh network. Alternative methods to control wireless devices were investigated in the non-controlled frequency spectrum. The aim of the research was to develop a protocol that can be loaded on a micro-controller with limited intelligence, controlling endpoints. The protocol minimises human interference and automatically negotiates which device becomes the master controller. The device is able to discover and locate neighbour devices in range. The device has the capability to be stationary or mobile and host multiple control endpoints. Control endpoints can be digital or analogue, input or output, and belongs to a group like security, lighting or irrigation. These capabilities can change according to the solution’s requirements. Control endpoints with the same capabilities must be able to establish a connection between each other. An endpoint has a user-friendly name and can update the remote endpoint with the description. When a connection is established both endpoints update each other with their user-friendly name and their status. A local endpoint can trigger a certain action on a receiving control point. The system was tested with a building monitoring system because it is static and a less expensive choice, thus making the evaluation more suitable. A simulator for a personal computer was developed to evaluate the new protocol. Finally, the protocol was implemented and tested on a micro-controller platform.

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Dirr, Enya Maria. "O fenómeno da deflação na Zona Euro e a política monetária não convencional." Master's thesis, Instituto Superior de Economia e Gestão, 2015. http://hdl.handle.net/10400.5/10857.

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Mestrado em Economia Internacional e Estudos Europeus
Todas as referências sobre as quais a Zona Euro se ergueu foram postas em causa no dia em que se iniciou a crise. O choque inicial teve início com a chamada crise do suprime nos Estados Unidos tendo-se alastrado globalmente afetando, de forma particular, a União Europeia. Esta ganhou uma dinâmica própria na sequência de problemas estruturais já existentes na União, que vieram ao de cima, impedindo-a de dar uma resposta coerente aos problemas da crise conjuntural. O presente estudo justifica-se pelas mudanças que se fizeram sentir desde então. Pode-se mesmo classificar o período iniciado de transformador, inovador, extravagante ou, simplesmente, incomum, no quadro do que tem sido a evolução da zona euro. Várias ocorrências atípicas se sucederam: estagflação seguida de deflação, taxas de juro nulas e medidas extraordinárias de política monetária. O foco do presente trabalho recai sobre o fenómeno da deflação e das medidas extraordinárias de política monetária, incluindo as taxas de juro nulas e o que daí resulta. Assim, pretende-se dar resposta à questão se as medidas não convencionais do Banco Central Europeu conseguiram dar resposta ao fenómeno da deflação (e taxas de inflação muito reduzidas) recuperando a estabilidade de preços. Para isso, utiliza-se uma abordagem teórico-descritiva, assente numa análise de alguns indicadores, posteriormente analisados de forma qualitativa. Concluiu-se que, apesar das medidas inovativas, a abordagem do BCE não conseguiu até agora dar resposta aos problemas essenciais vividos pelos Estados-Membros da Zona Euro, nomeadamente, o da estabilidade de preços.
All the foundations on which the Euro Zone rose were called into question in the day that the current crisis began. The initial impact began with the so-called subprime crisis in the United States taking up sprawled globally affecting, in a very particular way, the European Union. This gained its own dynamics, worsening the already existing structural problems, and blocking a coherent and united response to the crisis. This study is justified by the dramatic changes felt since then. This period may even be classified as transforming, innovative, extravagant or, at least, unusual in the context of what has been the evolution of the eurozone. Several atypical events have taken place: deflation followed by stagflation, zero interest rates, and extraordinary monetary policy measures. This work focuses on the deflation phenomenon and the extraordinary monetary policy measures, also including the zero interest rates and its related effects. Thus, it is intended to answer the question whether the unconventional measures the European Central Bank failed to respond to the phenomenon of deflation (and very low inflation rates) restoring price stability, or not. For this, a theoretical and descriptive approach was employed, based on the analysis of certain indicators, posteriorly explored in a quantitative way. The key conclusion was that, despite all the innovative measures, the ECB approach did not succeed in solving effectively the critical problems faced by the EU Member-States, in particular, price stability.

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Li, Jing, and 李靜. "Policy coordination in China: the cases of infectious disease and food safety policy." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B43703823.

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Oliveira, Edinaldo Silva de. "Avaliação estatística e protocolo para uso de cateter central de inserção periférica na oncohematologia." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2582.

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O Cateter Central de Inserção Periférica (PICC) constitui-se de dispositivo intravenoso, instalado através de uma veia periférica, que avança até a veia cava adquirindo características de cateter central. Neste sentido, o presente estudo teve como objetivo geral: identificar as condições de viabilidade para a definição de padrões e protocolos que possibilitem a utilização do PICC em pacientes adultos e pediátricos. E como objetivos específicos: analisar o desempenho da primeira e terceira geração de PICC em pacientes da oncohematologia comparando com a literatura internacional; detectar pontos sensíveis no contexto do uso do PICC para a proposição de protocolo; propor instrumento para a coleta e investigação de relevância de dados e variáveis; e propor protocolo de utilização do PICC para pacientes pediátricos e adultos. Trata-se de estudo descritivo exploratório observacional prospectivo longitudinal com abordagem quantitativa. A pesquisa foi desenvolvida na Unidade de Hemoterapia, Hematologia e Oncologia (UHHO) nos setores: Serviço de Transplante de Medula Óssea (STMO), Quimioterapia de Alto Risco (QTAR) e seus ambulatórios, Unidade de Terapia Intensiva (UTI) cardíaca, clínica médica e pediátrica, num hospital de ensino da região do sul do país. A amostra foi não-probabilística, por conveniência constituída de dois grupos, (Grupo 1) pacientes que utilizaram a primeira geração do PICC e (Grupo 2) pacientes que utilizaram a terceira geração do dispositivo. Os dados foram coletados no período de janeiro de 2015 a agosto de 2016 através de instrumento elaborado para este estudo, contendo 22 variáveis sócio-demográficas e 35 variáveis clínicas. 40 PICCs primeira geração foram inseridos em 36 pacientes por técnicas “às cegas”, totalizando 830 dias de cateter, média de 20,71 dias, tendo alcance mínimo de dois e máximo de 141 dias. Quanto à terceira geração do cateter, dez PICCs foram inseridos em dez pacientes por Técnica de Seldinger Modificada (TSM) guiados pelo Ultrassom (US), totalizando 397 dias de cateter, média de 39,7 dias com alcance mínimo de dez e máximo de 86 dias. Realizou-se análise descritiva por meio da distribuição de frequência absoluta, média e desvio padrão. Posteriormente, todas as variáveis foram analisadas pelo ‘Software R’, identificou-se 11 componentes principais que fortemente se relacionaram e constituíram a base do Modelo de Equações Estruturais (MEE). Estas variáveis expressam-se de maneira relevante para o desenvolvimento de investigações futuras. Em suma, o PICC pode ser utilizado com sucesso na maioria dos pacientes internados na oncohematologia e em outros setores no ambiente hospitalar, assim como em crianças. Pode ser inserido por enfermeiros, desonerando o ambiente cirúrgico, processo anestésico e o médico especialista, conferindo-lhes autonomia.
The Peripherally Inserted Central Catheter (PICC) consists of an intravenous device, installed through a peripheral vein, wich advanced to the vena cava acquiring central catheter characteristics. In this sense, the present study had as general objective: to identify the feasibility conditions for the definition of standards and protocols that allow the use of PICC in adult and pediatric patients. And as specific objectives: to analyze the performance of the first and third generation of PICC in oncohematology patients comparing with the international literature; to detect sensitive points in the context of the use of the PICC for the protocol proposal; propose an instrument for the collection and relevant investigation of data and variables; and to propose protocol of use of PICC for pediatric and adult patients. This is a descriptive prospective longitudinal observational exploratory study with a quantitative approach. The research was developed in the Hematology, Oncology and Hematology Unit (UHHO) in the following sectors: Bone Marrow Transplantation Service (STMO), High Risk Chemotherapy (QTAR) and its outpatient clinics, Intensive Care Unit (ICU), cardiac, medical clinic and pediatric in a teaching hospital in the southern region of the country. The sample was non-probabilistic, for convenience consisted of two groups, (Group 1) patients who used the first generation of PICC and (Group 2) patients who used the third generation of the device. Data were collected from January 2015 to August 2016 through an instrument developed for this study, containing 22 socio-demographic variables and 35 clinical variables. 40 firstgeneration PICCs were inserted in 36 patients by "blind" techniques, totaling 830 days of catheter, average of 20.71 days, with a minimum range of two and a maximum of 141 days. Regarding the third generation of the catheter, ten PICCs were inserted in ten patients by Ultrasound-guided Modified Seldinger Technique (TSM), totaling 397 days of catheter, mean of 39.7 days with a minimum range of ten and a maximum of 86 Days. A descriptive analysis was performed by means of the absolute frequency distribution, mean and standard deviation. Afterwards, all variables were analyzed by 'Software R', we identified 11 main components that were strongly related and formed the basis of the Structural Equations Model (MEE). These variables express themselves in a relevant way for the development of future investigations. In summary, PICC can be used successfully in most patients admitted to oncohematology and other sectors in the hospital setting, as well as in children. It can be inserted by nurses, discharging the surgical environment, anesthetic process and the specialist doctor, granting them autonomy.

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Jackson, Linda. "Food safety management and associated food handler behaviours in a prominent South African entertainment facility." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2011. http://hdl.handle.net/11462/143.

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Thesis (M. Tech. Environmental health) -- Central University of technology, Free State, 2011
Millions of people in South Africa eat out every day, utilising the food service sector. Although the lack of an effective reporting system makes it difficult to know how many of these people suffer from food-borne illness, statistics from the developed countries show that this number may be significant. There is, therefore, the need to ensure that the food service sector, which encompasses fast food outlets, hotels and similar accommodation outlets offering food and beverage services, restaurants, caterers, etc., implement effective food safety management systems. Internationally, the trend has been that food safety management systems should be based on the internationally accepted Hazard Analysis Critical Control Point (HACCP) principles. In South Africa, the implementation of HACCP as a food safety management system has been driven by international trade requirements where foods are exported to countries such as the European Union or the United States of America. A national regulation requiring HACCP implementation was promulgated in 2003, but compliance is not yet required for the food service sector. Currently, neither of the above mentioned factors put adequate pressure on the food service sector to implement formal food safety management systems. However, increasing international tourism and the hosting of international sporting events has brought this sector under scrutiny. Food handlers have been implicated in many outbreaks of food-borne illness and much research has been done to investigate causal factors in this regard. Food handler training has been proposed as a strategy to improve food safety practices. However, research has shown that the traditional provision of food safety and food hygiene knowledge does not equate to improved food safety behaviours. Some authors postulate that the organisational context, created largely by the management of an organisation, is of greater significance than training. Less research is available on these management factors – defined as the situational factors when discussing organisational culture, or defined as enabling and reinforcing factors when discussing food handler behaviour. This study commenced with the hypothesis that food handlers are not able to implement the correct food safety behaviours in the absence of sufficient management support. This support would require appropriate policies regarding food safety, the provision of training and infrastructure and enforcing the correct behaviours by line management, as a minimum. The aim of this study was to investigate and assess the role of line management in relation to food safety at a prominent South African entertainment facility. In order to achieve this, the following objectives were defined for the study: to conduct a qualitative assessment of the role of management in food safety, to assess the role of management in the provision of food safety training and to assess the role of management in the provision of a basic hygiene infrastructure at the study site in order to allow food handlers to carry out the correct behaviours. The objective of conducting a qualitative study of management practices, policies and resource provision with respect to food safety revealed that there was no formal evidence of management commitment to food safety other than the recent provision of food handler training. The findings also indicated a lack of a formal management system for food safety at the study site. In the exploratory survey of food safety training and knowledge, results showed that only 60 % of staff in the survey had received training. This indicates that at the time of the survey, the study site did not fully comply with the minimum legal requirements for food handler training. The results of the employee survey further indicated that employees were aware of the importance of hand washing although it was not possible to determine whether this knowledge was as a result of the training intervention or prior knowledge. Many of the supervisors were not yet trained in food safety and the impact of the food safety training intervention on related behaviours at the site will require further in-depth assessment. Upon investigating the food hygiene infrastructure provided at the study site to allow food handlers to carry out the correct behaviours, findings indicated that although the personnel hygiene programme addressed most of best practice requirements in design, the implementation of the hand washing requirements was not aligned with accepted norms due to the lack of sufficient hand wash basins. The provision of facilities such as sufficient and conveniently located hand wash basins is a management function and findings suggest that, as a priority, management should ensure that they are not contributing to the lack of implementation of the correct food safety behaviours of food handlers as a result of failing to provide the necessary resources. The results of this study should be of value in the food service sector, specifically hotel kitchens, as a guideline to ensure that management plays an effective role in facilitating food safety management systems. A robust food safety and food hygiene training programme for all levels of the organisation is essential in ensuring adequate knowledge of food safety hazards and correct practices. Training should be supported by daily supervision of food safety controls, management commitment and a work environment that supports the implementation of the correct behaviours. Literature has shown that undesirable practices are often deeply rooted in kitchen culture. It has further been commented that culture changes require a top-down approach which usually involves working with the leadership of the organisation. Important policies and procedures generally originate from the management tiers and will always require the concurrence of management in providing resources, altering priorities or otherwise changing how things are done in the organisation. The results of this study are invaluable in highlighting areas in an organisation that could be targeted to change the kitchen culture. Such changes are primarily the responsibility of management. Ultimately, this study endeavours to contribute to the body of knowledge pointing to the role of social-behavioural aspects in ensuring food safety and thereby consumer well-being.

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De, Wit Roland Duyvené. "Provisioning VolP wireless networks with security." Thesis, Bloemfontein : Central University of Technology, Free State, 2008. http://hdl.handle.net/11462/47.

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Slabbert, Róan Stephanus. "Evaluation of acid resistance in food-associated bacteria." Thesis, Bloemfontein : Central University of Technology, Free State, 2011. http://hdl.handle.net/11462/147.

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Thesis (M. Tech. Environmental health) -- Central University of technology, Free State, 2011
Although the application of low pH is common practice in food preservation, the emergence of acid tolerance has been reported world-wide amidst a growing concern that preservation with weak acids, such as organic acids may be influenced as a result of food-borne bacteria becoming acid tolerant or acid resistant. The present study was conducted to assess the acid tolerance of a wide range of bacterial species and consequently the sustainable application of organic acids as food preservatives in particularly acidic foodstuffs. Acid tolerance was determined in 19 bacterial strains predominantly associated with food spoilage and food poisoning. After exposure to hydrochloric acid 16% of the isolates were found to be intrinsically tolerant to low pH and included amongst others the enteric bacteria Escherichia coli and Salmonella spp. The latter organisms are known causative agents in food spoilage and poisoning, and the results highlight the predicaments related to their ability to survive in acidic foodstuffs as well as the human gastric environment. Bacterial strains were further exposed to increasing concentrations of various acidic foodstuffs in order to determine the development of acid tolerance by gradual decrease in pH, as opposed to exposure to acid shock. After induction, the protein profiles of resulting acid tolerant isolates were compared with those of the original un-induced strains. Exposure to acidic foodstuffs resulted in various survival profiles, where not only pH but also the type of acidulant (foodstuff or inorganic acid) were found to be contributing factors in acid tolerance development. Bacterial protein composition after exposure to acidic foodstuffs showed considerable variation which may be indicative of acid tolerance development whereas the mechanisms involved may be the result of multiple modifications in bacterial composition. After the induction of acid tolerance, susceptibility of induced strains to various organic acids were determined at various pH values. This was done to investigate whether acid tolerance would influence the inhibitory activity of organic acids as antimicrobial agents in acidic food. Decreased susceptibility was not significantly demonstrated with the exception of only selected isolates, the latter including E. coli and S. typhimurium. Organic acid activity was found to be much more effective at lower pH values and it would be necessary to elucidate whether this inhibition is the result of a lower pH or more specifically the activity of the organic acids. The effect of exposure to an acidic environment on phenotypic characteristics of Gram-negative bacteria, and more specifically psychrotrophic organisms was evaluated in order to show the combined effect of organic acids and low temperature preservation. The characteristic yellow pigment of various Chryseobacterium species was found to be not as apparent after acid exposure while in some cases the colonies were observed as white. In Pseudomonas aeruginosa the characteristic green pigment was much more prominent after acid exposure. These morphological alterations may be important factors that should be considered in identification procedures employed in food safety laboratories. Finally, the influence of acidic exposure via acidic foodstuffs and also organic acids on the protein composition and outer membrane protein structure of various bacterial cells was investigated. No specific relationships with the MICs (Minimum Inhibitory Concentrations) of organic acids after induction with the selected acidic foodstuffs could be established, although various differences were found in protein expression. From the results, it may be suggested that the outer membrane of various pathogenic bacteria is involved in acid tolerance development and this supports the reports on the importance of membrane integrity in the protection against low pH. In conclusion, the study endeavoured to add to the body of knowledge with regard to alternative food preservation regimes utilising organic acids, either solely or in combination with selected extrinsic and intrinsic parameters.

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Van, der Walt Jacobus Gert. "Radiation field shaping through low temperature thermal-spray in radiotheraphy." Thesis, Bloemfontein : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/116.

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Thesis (D. Tech.) -- Central University of Technology, Free State, 2009
Superficial cancerous lesions are commonly treated through low energy X-ray or electron radiation in radiotherapy. The treatment units that produce the radiation are equipped with square, rectangular and round applicators of different sizes. These applicators attach to the treatment units and define the radiation field size applied during treatment. An applicator is chosen to fit the shape of the cancerous lesion on the patient as closely as possible. Since cancerous lesions are irregular in shape, there will always be an area of healthy tissue between the edge of the lesion and the edge of the standard field shape. This healthy tissue will be irradiated along with the lesion during treatment which is undesirable since the cancer wound heals through reparative growth of the surrounding healthy tissue after treatment. Traditional techniques that were developed to shield this healthy tissue and thus shape the radiation field to the shape of the lesion present various shortcomings. This study introduces a new thermal-spray process for producing radiation field shaping shields which overcomes most of the shortcomings encountered with the traditional field shaping techniques. Since none of the commercially available thermal-spray equipment could be used to produce field shaping shields, new thermal-spray equipment was designed and fabricated tailor made to the application. Different techniques to determine the contours of the treatment area on the patient were investigated. These included a patient contact technique using a plaster bandage impression and a non-contact technique using 3D laser scanning. From the plaster bandage impression a plaster model can be produced onto which a high density low melt material such as Wood’ s alloy can be thermally sprayed to produce a field shaping mask. A model can also be produced from the 3D laser scanning data through laser sintering (LS) in nylon polyamide powder or through computer numerical controlled (CNC) milling in a block of low density polyurethane. The thermal-spray technique was evaluated by comparing the field shaping ability of radiation shields produced through the technique to the field shaping ability of shields produced through the traditional techniques. Radiographic film was used for this purpose and the results are presented in the form of isodensity charts. The required thicknesses of thermal-sprayed field shaping masks to shield radiation of various energies were also determined. The thicknesses were determined through radiation transmission measurements of known thicknesses of sprayed sheets of Wood’ s alloy. X-ray imaging showed that there were no defects present within thermal-sprayed layers of Wood’ s alloy that may negatively affect the shielding ability of masks produced through the technique.

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Marshall, Alasdair J. "An assessment of the model of human personality which is central to Vilfredo Pareto's sociological theory, followed by the development and application of new psychometric measures to determine the extent to which this model is predictive of differences be." Thesis, University of Glasgow, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325395.

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Smith, Elvina Melinda. "Influence of extrinsic stresses on growth and endotoxin profiles of escherichia coli and pseudomonas aeruginosa." Thesis, Bloemfontein : Central University of Technology, Free State, 2011. http://hdl.handle.net/11462/152.

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Thesis (M. Tech. Environmental health) -- Central University of technology, Free State, 2011
The threat to the world food supply and the concern for public health as a result of food-borne diseases has been established as a constant global problem. The safety of food, in particular, is of significance to consumers and producers alike. Regarding the diseases related to food-borne pathogens, the disease syndromes affecting the entire human body has become inestimable. The focus of the study was to establish the effect of sanitisers, detergents and household storage temperatures on the growth profiles and toxicity of typical food related organisms. The endotoxin, LPS of these Gram-negative organisms in communal growth as compared to pure culture was the focus of the investigation. Pure and communal samples were grown in the presence of the extrinsic stresses including storage temperature. The change in toxicity was measured using the Limulus amoebocyte lysate test and the possible change in the immune response was determined using the porcine-IL-6 test. The first obvious finding was that the overall sensitivity of organisms was similar for the same sanitiser and the same detergent. The sensitivity of the community varied slightly but in principle followed the same pattern as the individual organisms. The LD50 for all growth samples were as follows: 32 X 104 PPM for sanitiser 1 and sanitiser 2, and 16X 104 PPM for detergent 1 and detergent 2. Growth in community was found not to be the arithmetic sum of the individual growth patterns. The detergents had a marked effect on the growth of all samples throughout the growth cycle. The sub-optimum household storage temperatures inhibited the growth throughout the cycle but growth did not cease entirely. This finding may have revealed that the acceptable refrigeration temperatures still allows for pathogen growth and thus for biofilm formation. Furthermore, the response of the community to the extrinsic stresses appears to be entirely different to the pure culture and therefore needs further exploration to address the problem. Regarding the quantification by LAL, it was found that the enumeration of the food-borne pathogens isolated from households might not be indicative of acclimatisation obtained over short periods of time and the causal stress turning these organisms into more or less toxic pathogens. The sanitisers and detergents induced competition in colonial fashion and the growth varied between feast and famine. The extrinsic stresses had a more observable effect on the older biofilm as this was shown by a decrease in toxicity. The toxicity as quantified by porcine-IL-6 yielded a mixture of stimulation levels for the cytokine. The toxicity change indicated by the test showed a variation between lowering and noticeable elevation for pure cultures. A marked elevation in toxicity was detected in community at storage temperature 4°C. The study would suggest that porcine IL-6 is not an accurate biomarker for pyrogenicity since its sensitivity is questionable and its inability to indicate toxicity if there is a possible change in the LPS structure. It should be said that further elucidation is needed to support this finding. Having said all that, it is no surprise that the validation for the two tests favours the LAL procedure. The large room for pre-test stimulation in pigs’ blood also tends to cast a shadow on the IL-6 findings. The findings of the study contribute to the body of knowledge covering the effects and quantitative analysis of toxins in food. This should add to safety assurance by sensitizing the industry regarding the most suitable analytical methodologies to apply.

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Raphela, Selepeng France. "Occupational exposure to electromagnetic fields in the heavy engineering CO2 welding industry in the Mangaung Metropolitan municipality." Thesis, Bloemfontein : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/181.

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Thesis (D. Tech. (Environmental Health)) -- Central University of technology, Free State, 2013
Some epidemiological studies suggest that exposure to high levels of electromagnetic fields (EMFs) may be linked with the development of adverse health effects. However there is still controversy on this matter. Due to rapid technological growth in the modern society, employees in the welding and electrical industries are highly exposed to electromagnetic fields and may be at a high risk for developing occupational diseases. The health effects which may result from exposure to electromagnetic fields are related to the strength and frequency of the fields. This study was conducted to (i) assess the exposure levels to EMFs in the welding industry, (ii) determine the possible health risks associated with exposure levels, and (iii) develop a health and safety model to guide the industry on how to reduce exposure to EMFs. The study was conducted in one mega welding company in the Mangaung Metropolitan Municipality. Welders, fitters and office workers (88 in total) gave consent to participate in the study and completed questionnaires (ethical clearance attached). Measurements of extremely low frequency EMFs were taken in workshop A, workshop B and working offices. Measurements for magnetic fields were taken at distances of 1, 2 and 3 meters (m) from the EMFs sources. The exposure levels of magnetic fields were very high in the workshops, with welders and fitters exposed to about 7.6 microtesla (μT). Electric fields were relatively low in all workstations. Participants in the study were experiencing symptoms of ill health such as headaches, sleep disorders, fatigue and distress. The symptoms reported by the workers were similar in the both groups (exposed and control). There is no clear relationship between recorded exposure levels and the development of the reported symptoms. The health and safety model was developed to guide the industry to reduce exposure to electromagnetic fields. The model describes the implementation of engineering and administrative control measures in an effort to reduce exposure to EMFs. The model also highlights the importance of wearing personal protective equipment to shield against EMFs amongst others. This study suggests that occupational exposure to high levels of extremely low frequency EMFs may increase the risk for development of chronic diseases such as leukaemia, brain and breast cancer and other diseases among highly exposed employees. Implementation of safety measures is necessary to reduce exposure to EMFs.

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Nhlapo, Nthabiseng. "Hygiene and nutritional content of the National School Nutrition Programme in Bloemfontein, South Africa." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/180.

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Thesis (M. Tech. (Environmental Health)) -- Central University of technology, Free State, 2013
Malnutrition and concomitant infections are major contributing factors to child morbidity and mortality in developing countries such as South Africa. Globally, children benefiting from school feeding programmes are generally from communities with low socio-economic statuses. The meals provided through feeding schemes, such as the National School Nutrition Programme (NSNP) in South Africa, are aimed at significantly supplementing the beneficiaries’ daily energy and nutrient requirements. The possible nutrient deficiency of meals provided through such programmes compromises the nutritional well-being of children, promotes malnutrition and renders children more susceptible to infectious diseases. Furthermore, illness, particularly caused by diarrhoeal and infectious diseases, is a major factor contributing to child malnutrition as the human body is unable to efficiently digest foods and absorb nutrients during illness. Therefore, the microbiological safety of the foods served to children via feeding schemes is essential. In an effort to contribute towards the safety and wholesomeness of foodstuffs served through the NSNP, the present study was conducted with a view to assess the nutritional quality and safety of the foodstuffs. The knowledge, attitudes and practises (KAP) of food handlers and NSNP representatives/committee members at the schools were also investigated in order to assess origins of potential food contamination. Data collected via nutritional analyses of meals served to school children were compared to the nutrient-based standards set by the United Kingdom as guidelines for an average school lunch. The carbohydrate, energy, calcium and zinc contents of the school meals were below the standards, the majority of the meals met the protein and iron standards and all meals complied with the standards for lipid and vitamin C contents. During the microbiological analysis study, preparation surfaces yielded higher counts of all detected organisms (total coliforms, Escherichia coli, Staphylococcus aureus and yeasts and moulds) compared to the hands of food handlers. Therefore possible sources of contamination may be foodstuffs, animal pests and environmental elements such as dust. However, significant differences of surface microbial counts could not be established (P > 0.05) and thus cross-contamination may have resulted among surfaces, possibly augmented by shortfalls in cleaning regimes. The majority of the participants of the questionnaire survey reportedly washed their hands and cleaned all surfaces several times during the day with water and detergent. In addition, a disinfectant was used by some of the food preparers during cleaning. Furthermore, participants stated that their aprons were washed daily. These claims were in agreement with the findings of the surface microbial study with regards to the hands, however, they did not match the findings of the preparation surfaces which contained the highest counts of total coliforms, E. coli and S. aureus of the three surfaces analysed, and aprons responsible for the highest yeast and mould counts. Improper storage and food preparation methods, such as the application of high temperatures, excessive exposure to UV light and oxygen, and high moisture conditions, may result in the deterioration of nutrients. Storage conditions which may permit pest infestation may also increase the risk of food-related illnesses and risk could be further elevated by application of improper cleaning and sanitation practices. In order for the NSNP to operate effectively, it is essential that the national and provincial Departments of Basic Education, which are responsible for the overall administration of the NSNP, and schools’ personnel function in an integrated manner through support structures and effective communication. Infrastructural limitations (lack of proper kitchen facilities and ventilation) and shortage of resources while administering the NSNP were the main challenges observed during the present study. Due to these hurdles, adhering to food safety practices and maintaining nutritional quality of foods may be a challenge. Continuous training in personal and general hygiene is also a necessity in preserving food safety. Furthermore, nutritional quality of foodstuffs may be preserved through proper storage practices and application of preparation methods which minimize loss of nutrients.

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Marešová, Edita. "Transformace účetnictví státní správy a samosprávy v České republice." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-162525.

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The subject of this thesis is a description of the Integrated information Treasury System and detailed description of the accounting reform of public finances in the Czech Republic, effective from 1 January 2010. The work is focused on the accounting state and local governments. The main part is devoted to changes in accounting rules, described in detail the issue of depreciation, reserves, transfers and accruals. The last chapter concerns the reform of public finances in the Slovak Republic.

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Amri, Anis. "Autour de quelques statistiques sur les arbres binaires de recherche et sur les automates déterministes." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0301.

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Cette thèse comporte deux parties indépendantes. Dans la première partie, nous nous intéressons à l’analyse asymptotique de quelques statistiques sur les arbres binaires de recherche (ABR). Dans la deuxième partie, nous nous intéressons à l’étude du problème du collectionneur de coupons impatient. Dans la première partie, en suivant le modèle introduit par Aguech, Lasmar et Mahmoud [Probab. Engrg. Inform. Sci. 21 (2007) 133—141], on définit la profondeur pondérée d’un nœud dans un arbre binaire enraciné étiqueté comme la somme de toutes les clés sur le chemin qui relie ce nœud à la racine. Nous analysons alors dans ABR, les profondeurs pondérées des nœuds avec des clés données, le dernier nœud inséré, les nœuds ordonnés selon le processus de recherche en profondeur, la profondeur pondérée des trajets, l’indice de Wiener pondéré et les profondeurs pondérées des nœuds avec au plus un enfant. Dans la deuxième partie, nous étudions la forme asymptotique de la courbe de la complétion de la collection conditionnée à T_n≤ (1+Λ), Λ>0, où T_n≃n ln⁡n désigne le temps nécessaire pour compléter la collection. Puis, en tant qu’application, nous étudions les automates déterministes et accessibles et nous fournissons une nouvelle dérivation d’une formule due à Korsunov [Kor78, Kor86]
This Phd thesis is divided into two independent parts. In the first part, we provide an asymptotic analysis of some statistics on the binary search tree. In the second part, we study the coupon collector problem with a constraint. In the first part, following the model introduced by Aguech, Lasmar and Mahmoud [Probab. Engrg. Inform. Sci. 21 (2007) 133—141], the weighted depth of a node in a labelled rooted tree is the sum of all labels on the path connecting the node to the root. We analyze the following statistics : the weighted depths of nodes with given labels, the last inserted node, nodes ordered as visited by the depth first search procees, the weighted path length, the weighted Wiener index and the weighted depths of nodes with at most one child in a random binary search tree. In the second part, we study the asymptotic shape of the completion curve of the collection conditioned to T_n≤ (1+Λ), Λ>0, where T_n≃n ln⁡n is the time needed to complete accessible automata, we provide a new derivation of a formula due to Korsunov [Kor78, Kor86]

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42

Jing-Yuh, Huang, and 黃精裕. "Testing the Secondary Mathematical Teachers’ Mathematical Pedagogical Content Relative Knowledge By measure of central tendency and of variability." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/cs922v.

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碩士
國立臺北教育大學
數學暨資訊教育學系(含數學教育碩士班)
96
This study tested the secondary mathematical teachers’ Mathematical Pedagogical Content Relative Knowledge(MPCRK). The first step in this study was investigating and comparing many literatures, and inducting the content of MPCRK. The second step were deeping interview of 10 senior secondary mathematics teachers and questionnaire investigation of 236 secondary mathematics teachers. The third step were using the analysis of variance (ANOVA) to investigate the factors which related with the secondary mathematical teachers’ MPCRK, and the analysis of Structural Equation Modeling (SEM) to construct the model of MPCRK. The purpose of this study was to know the knowledge and model of the secondary mathematical teachers that they have to be provided with “measure of central tendency and of variability”. The findings of this study were listed below: 1. The secondary mathematical teachers have to be provided with at least three kinds of knowledge about “measure of central tendency and of variability” of mathematical pedagogy : content knowledge(CK), pedagogical knowledge(PK), knowledge of learners and their characteristics(LK). It is important to MPCRK. 2. The factors which related with the secondary mathematical teachers’ MPCRK. (1) The secondary mathematical teachers’ pedagogical knowledge has differences because of the genders. (2) The secondary mathematical teachers’ knowledge of learners and their characteristics has differences because of the in-service training hours. (3) The secondary mathematical teachers’ content knowledge has differences because of the experience and region. (4) The secondary mathematical teachers’ MPCRK didn’t has differences because of the age, education, seniority and magnitude of school. 3. About the model of MPCRK : The three kinds of knowledge(CK,PK,LK) can predict the secondary mathematical teachers’ MPCRK, but the MPCRK would be moderated by teaching experience and in-service training hours.

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43

"Robust Distributed Parameter Estimation in Wireless Sensor Networks." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.46285.

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abstract: Fully distributed wireless sensor networks (WSNs) without fusion center have advantages such as scalability in network size and energy efficiency in communications. Each sensor shares its data only with neighbors and then achieves global consensus quantities by in-network processing. This dissertation considers robust distributed parameter estimation methods, seeking global consensus on parameters of adaptive learning algorithms and statistical quantities. Diffusion adaptation strategy with nonlinear transmission is proposed. The nonlinearity was motivated by the necessity for bounded transmit power, as sensors need to iteratively communicate each other energy-efficiently. Despite the nonlinearity, it is shown that the algorithm performs close to the linear case with the added advantage of power savings. This dissertation also discusses convergence properties of the algorithm in the mean and the mean-square sense. Often, average is used to measure central tendency of sensed data over a network. When there are outliers in the data, however, average can be highly biased. Alternative choices of robust metrics against outliers are median, mode, and trimmed mean. Quantiles generalize the median, and they also can be used for trimmed mean. Consensus-based distributed quantile estimation algorithm is proposed and applied for finding trimmed-mean, median, maximum or minimum values, and identification of outliers through simulation. It is shown that the estimated quantities are asymptotically unbiased and converges toward the sample quantile in the mean-square sense. Step-size sequences with proper decay rates are also discussed for convergence analysis. Another measure of central tendency is a mode which represents the most probable value and also be robust to outliers and other contaminations in data. The proposed distributed mode estimation algorithm achieves a global mode by recursively shifting conditional mean of the measurement data until it converges to stationary points of estimated density function. It is also possible to estimate the mode by utilizing grid vector as well as kernel density estimator. The densities are estimated at each grid point, while the points are updated until they converge to a global mode.
Dissertation/Thesis
Doctoral Dissertation Electrical Engineering 2017

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44

"Central tendency in answering questionnaire for Hong Kong Chinese." Chinese University of Hong Kong, 1992. http://library.cuhk.edu.hk/record=b5887141.

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by Shum Suk-Chong.
Thesis (M.B.A.)--Chinese University of Hong Kong, 1992.
Includes bibliographical references (leaves 48-49).
ABSTRACT --- p.ii
ACKNOWLEDGEMENTS --- p.iii
TABLE OF CONTENTS --- p.iv
LIST OF FIGURES --- p.v
LIST OF TABLES --- p.vi
CHAPTER
Chapter I --- INTRODUCTION --- p.1
Statement of Problem --- p.2
Focus of Research --- p.3
Job Characteristics Model --- p.4
Number of Response Categories --- p.6
Response Sets of the Chinese --- p.7
Importance of this Study --- p.9
Development of the Research Hypotheses --- p.10
Research Hypothesis in the Null Form --- p.10
Chapter II --- RESEARCH METHODOLOGY --- p.12
Design of Questionnaire --- p.12
Layout of Section I --- p.13
Layout of Section II --- p.14
Layout of Section III --- p.15
Pre-testing and Adjustments --- p.16
Selection of Respondents --- p.16
Estimates for the Variables --- p.17
Transforming the Scale --- p.18
Response Rate --- p.19
Chapter III --- RESEARCH FINDINGS --- p.21
Research Hypotheses --- p.21
Research Hypothesis in the Null Form --- p.22
Reliability Coefficients --- p.22
Means and Standard Deviations --- p.24
T-tests on Means and F-tests on Standard Deviations --- p.24
Correlation Among Factors --- p.25
Conclusion --- p.26
Chapter IV --- CONCLUSIONS --- p.27
Response Scale --- p.27
Validity of Job Characteristics Model in Hong Kong . --- p.28
Characteristics of University Graduates in Hong Kong --- p.29
Limitations of Study --- p.29
Implications for Future Study --- p.31
APPENDIX --- p.33
Questions used in Questionnaire --- p.44
REFERENCES --- p.48

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45

Pan, Bo-Yu, and 潘柏宇. "Some Case Studies of Central Configurations and Central Measures." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/c6vg2x.

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46

Li, Jheng-ru, and 李政儒. "Variational tendency of PM10 and evaluation of fugitive dust from traffic in central Taiwan." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/17097709410458765940.

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碩士
國立雲林科技大學
環境與安全衛生工程系碩士班
100
Variational tendency of particulate matter less than 10 micrometer (PM10) using the data from 12 air quality monitoring sites of central Taiwan was investigated and comparison with calculated fugitive dust emission between using Taiwan Emission Data System (TEDS) and using total suspended particulate (TSP) concentration was studied. First, the data of PM10 concentration from 2000 to 2010 indicated better and better air quality at central Taiwan, showing the highest PM10 concentration of 108.07 μg/m3 at central Taiwan and the lowest PM10 concentration of 43.96 μg/m3 at central Taiwan. For evaluation of fugitive dust by vehicles, comparison with calculated emission using TEDS and TSP showed that the result of calculated emission using TEDS was eight-fold high than calculated emission using TSP before washing work of the road due to the silt soil value showing 0.67 g/m2. Moreover, the result of calculated emission using TEDS was three-fold high than calculated emission using TSP after washing work of the road due to the silt soil value showing 0.13 g/m2. Therefore, evaluation models of fugitive dust from road should be modified by experimental data. In addition, a new method for evaluation of fugitive dust from road using weight of road dust was developed and it is a suggestion that weight should be less than 0.15 g for A level of road, between 0.15 and 0.6 g for B level, and more than 0.6 g for C level of road.

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47

Kao, Chunug-Liang, and 高中良. "Recruitment Military Measures , the External Environment and the Service Treatment to Study the Impact of the Departure Tendency." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/80884498837258407383.

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碩士
朝陽科技大學
企業管理系
104
With the change of pattern of the war in the information technology,and Manpower subjective and objective environmental changes, Republic of China Guojun Active for human resource structure adjustment,Gradually advancing towards the goal of full mercenary，Then sailors who left the camp was much lower setting goals,Thus lead to shortage of troops, combat skills and experience and other concerns of convergence,Factors affecting therefore sailors who left the camp to explore the wishes of the issue has become extremely urgent. This research aimed at discussion volunteer bondage soldiers of left camp wishes whether was extrinsic (Expected drop,military image,external effects factors) and internal(pay and welfare,job satisfaction,Organizational Commitment and leadership style)factors affecting,And air defense forces of the Volunteer military has soldiers and non-commissioned officers to serve as the research object to investigate,total issued questionnaire 400 copies, delete invalid questionnaire 148 copies, total made effective questionnaire 252 copies.The results show” Willingness to leave the camp continued to decrease”,And the willingness of soldiers left the camp to stay well below the non-commissioned officers of the battalion wishes. In addition, do not continue to stay to remain with the battalion's camp, Its influence willingness to leave the camp the two most important factors are pay and welfare and career planning, Finally, there is the military image；The first two factors that can increase the Volunteer military officers and soldiers left the camp was to increase the willingness to pay and commuting to work.

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48

"Condition measures and properties of the central trajectory of a linear program." Operations Research Center, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/2612.

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49

Lin, Jh-Siyuan, and 林志玄. "A Study on Integrated Conservation Measures for TouShe Creek Watershed in Central Taiwan." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/49068151308214813007.

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碩士
國立中興大學
水土保持學系所
95
Ming-Tan reservoir is located at the confluence of Shuili Creek and TouShe Creek near Sun Moon Lake in Nantou County. Ming-Tan power-station generates electric power by water of Sun Moon Lake at the day time, and using surplus electricity to release water back to Sun Moon Lake from the Ming-Tan reservoir at night. The catastrophic 1999 Chi-Chi earthquake caused many landslides in the watersheds of central Taiwan. In addition, with the heavy rain events occurred annually, most of the debris eroded from the landslides deposit at the torrent channels and/or reservoirs. There fore it is important to implement the well-planned strategies for minimizing the sedimentation to conserve the life span of reservoirs. Spatial distribution of landslides in Toushe watershed was extracted and determined in this study by using geographic information systems. Characteristics and the areas of landslides in Toushe creek watershed were investigated and determined. Universal Soil Loss Equation (USLE) couples with the concepts of sediment delivery ratio are applied to estimate watershed sediment yield. The calculated annual average sediment yield of the watershed is 229,640 m3, which is within 6% of the measured value 242,857 m3. For reducing flood and debris flow hazard of TouShe Creek, which is the major tributary of the Ming Tan reservoir watershed, the following conservation strategies are suggested. Firstly, watershed landslides rank as “A” degree risk should be treated separately at the areas of slope top, bare slope surface, slope toe, and the deposited sites. Secondly, at the location between 430 m upstream of the TD4 check dam and the place which Toushe Creek hydraulic construction installed should be protected by the dry masonry revetment, and its continued downstream section should be constructed RC revetment to prevent riverbank erosion. Thirdly, two check dams should be built to store the channel sediment and regulate sediment transportation for improving channel stability. Finally, channel sedimentation at the upstream of TD4 check dam should be dredged to increase the cross section area, protect the hydraulic structures at the downstream of TouShe Creek, and mitigate the sedimentation of the Ming-Tan reservoir. For sustainable watershed development, this study proposed that the total watershed should be divided into different zones based on the characteristics of environment resources and the community structures. Although the farm vacation areas, nature experience areas, and golf areas are already planned by the Sun Moon Lake National Scenery Bureau in the watershed, the additional zones such as: the ecological conservation areas, the areas for conservation enhancement, and the riparian areas along the TouShe creek are suggested by this study. These development proposals can increase the job opportunities for improved incomes and quality of life, and train local youths to participate in various community developments. Consequently the sustainable development of this will attract more highly-educated young people to return home and contribute to their home community.

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50

Yen, Yih-Shyang, and 嚴義祥. "A Study on Treatment Measures for Li-Shan Landslide Area in Central Taiwan." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/30069937517728344175.

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碩士
國立中興大學
水土保持學系所
94
Investigation and evaluation of local hydrogeological conditions can provide helpful information to the planning of landslide remediation work. Using records of boring-log and data from piezometers, a basic hydrogeologic data base can be established. Results from groundwater quality test and drain-out water quantity from drainage system combined with spatial analysis can help determine hydrogeological conditions in detail. This study investigates the treatment measures and their effects for the large Li-Shan landslide located at 35km of the central cross-island highway. The Li-Shan area has a complex geological condition. Lithological strata can be classified as colluvium, medium weathered slate, heavily weathered slate and base rock individually. Orientation of the strata judged from geological profiles are provided for the initial flow direction evaluation. Effectiveness of the drainage systems, the main measure applied for landslide remediation are discussed. These results provide additional information for future work. Around the central landslide zone near the Li-Shan grand hotel location, elevations of groundwater are dropped to about 4-28 meters after the installation of the drainage facilities. Basically, infiltrated water from rainfall in the central landslide zone can be drained safely. But, west and northeastern zones of the landslide area did not show sufficient drainage capabilities. The results of the water quality test indicates the existence of mostly shallow-layer groundwaters at the landslide site. At the central zone of the landslide site the total drainage amount significantly exceed the amount of infiltrated rainwater. This suggests a possible contribution of irrigation water from the adjacent Fu-sho-shan Vegetable Farm. Therefore, further studies should include a more detailed evluation of the role played by the off-site contribution to the landslide.

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