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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Dinâmica de configuração de regras para inovação : um olhar complexo e interteórico numa organização de pesquisa agrícola do agronegócio orizícola do Rio Grande do Sul

Dias, Marcelo Fernandes Pacheco January 2011 (has links)
Dois temas são característicos do contexto atual das organizações. Um, já consolidado, é o aumento da velocidade das inovações; o outro, é a necessidade de incorporar a perspectiva emergente da sustentabilidade nas práticas de inovação. A Teoria Neoschumpeteriana busca obter um domínio desses fenômenos dinâmicos da realidade econômica, em que a inovação, principalmente a tecnológica, é identificada como a força maior que propulsiona a dinâmica econômica. Entretanto, Hanusch e Pyka (2007) criticam a Teoria Neoschumpeteriana por entenderem que o desenvolvimento dos sistemas econômicos modernos incorpora a inovação tecnológica, assim como também a inovação organizacional, institucional e social e, por isso, os novos frameworks para estudos de sistemas econômicos, precisariam incorporar características de complexidade através do trânsito em diferentes teorias relevantes, levando em conta as raízes da Teoria Neoschumpeteriana, o que eles próprios não fazem. Assim, o objetivo geral de pesquisa foi o de propor um framework interteórico e complexo sobre a dinâmica da inovação e fazer a sua aplicação no Instituto Rio-Grandense do Arroz - IRGA. A metodologia utilizada foi de estudo de caso. Os dados foram coletados através de entrevistas e documentos. Cada uma das etapas realizadas na metodologia foi apoiada num estudo, a priori, sobre métodos que capturavam características de complexidade. A utilização de uma lógica abdutiva, prevista na metodologia, com constantes idas e vindas entre os conceitos teóricos construídos a priori e as informações advindas do campo empírico, fez emergir o conceito teórico de sistema econômico, como uma configuração complexa de múltiplos níveis de regras que se relacionam ao longo do tempo e se sucedem. Neste sentido, a presente pesquisa avançou ao identificar a emergência de regras, oriunda das teorias usadas, como uma qualidade nova e central, que em múltiplos níveis, compõe as configurações, que evoluem ao longo do tempo. Este avanço possibilitou estudar a história econômica do IRGA, não da perspectiva operacional, mas da perspectiva das regras genéricas, de maior nível, e das regras de menor nível associadas à regra genérica, numa perspectiva de configurações dinâmicas que evoluem, focado em inovações. A lógica abdutiva possibilitou avanços metodológicos na aplicação do método de análise qualitativa comparativa (QCA) no estudo das dinâmicas de configurações, já que o método tinha até então, sido aplicado numa abordagem estática. Os resultados indicaram, ainda, a presença de cinco regras genéricas no contexto de pesquisa do IRGA. O IRGA inseriu predominantemente, em suas atividades, de pesquisa a regra genérica de mais produtividade agrícola. As regras genéricas de gestão ambiental da propriedade agrícola, aumento do consumo do arroz, aumento da renda para o produtor foram inseridas nas atividades de pesquisa de modo marginal. A regra genérica denominada de negócios ambientais nas beneficiadoras de arroz ainda não foi inserida nas atividades de pesquisa do IRGA. A dinâmica de inserção destas regras genéricas no IRGA ocorre através de oito configurações de regras de nível zero e de segunda ordem, que seguem um conjunto de fases que foram denominadas de pré-distúrbio, origem, adoção, retenção e declínio. Uma característica nesta dinâmica é de que somente ocorreu a mudança de fase da regra genérica quando determinadas regras de segundo e de ordem zero estavam presentes. Como as fases de evolução das regras genéricas ocorreram em diferentes anos, no período entre 1969 e 2009, a combinação destas fases gerou seis configurações temporais de regras para inovação no IRGA. / Two themes are characteristic of the organizations on the current context. One is already established that is the increasing innovations speed. The other one is the need to incorporate the sustainability‘s emerging perspective in innovation practices. The Neo-Schumpeterian Theory seeks to obtain a domain on these dynamic phenomena of the economic reality, in which the innovation, especially technological, is identified as its greater propellent force. However, Hanusch and Pyka (2007) criticize the Neo-Schumpeterian Theory for understanding that the development of modern economic systems incorporate the technological innovation, as well as the organizational innovation, institutional, and social. Therefore, the new frameworks for the economic systems studies would need to incorporate some complexity features through traffic in different and relevant theories, taking into account the Neo-schumpeterian Theory roots, which they themselves do not do. Thus, the overall objective of this research was to propose an inter-theoretical and complex framework on the innovation dynamics and to make its application at the IRGA (Instituto Rio-Grandense de Arroz - Rice Institute of Rio Grande do Sul State, Brazil). We used the case study methodology. Data were collected by some interviews and from some documents. Each of the used methodology steps was supported in a priori study on methods that captured the complexity characteristics. The economic system‘s theoretical concept as a complex configuration of the multiple rules levels related over the time, and that succeed itself, came from an abductive logic use from the methodology, with constant goings and comings among the theoretical concepts a priori constructed, and from the empirical information from the field. In this sense, this research has advanced when identified the rules emergence, derived from the used theories as a new quality and centered, which at multiple levels composes the configurations that evolve over the time. This advance allowed the IRGA‘s economic history study, not from the operational perspective, but from the general rules perspectives of highest level and from the lowest level associated with the general rules perspectives, at a dynamic configurations perspective that evolve focusing on innovations. The abductive logic allowed the methodological advances in the method application of comparative and qualitative analysis (CQA) in the study of the configurations dynamics, since the method had until then been applied on a static approach. The results also indicated the presence of five generic rules in the context of the IRGA research. The IRGA inserted predominantly the general rule of most agricultural productivity in its research activities. The general rules of the farm environmental management, the increased rice consumption, and the increased income for producers have been included in the research activities marginally. The general rule of environmental affairs in the rice processing has not been incorporated into the IRGA research activities. The insertion dynamic of these general rules occurs through eight rules of level zero and second order configurations, which follow a stages set that were identified as pre-disturbance, origin, adoption, retention, and decay. A dynamic characteristic is that there was only a phase change of the general rule when certain rules of the second and zero order were present. As the phases of the generic rules development occurred in different years, from 1969 to 2009, these phases combination generated six rules temporal configurations for innovation in the IRGA.
112

Aten??o?! Pare?! A mobilidade por bicicleta e a rela??o ambiente urbano - normas de tr?nsito

Mascarenhas, Guilherme Paim 21 August 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-02T23:06:51Z No. of bitstreams: 1 GuilhermePaimMascarenhas_DISSERT.pdf: 2944281 bytes, checksum: 438ec06a374cf17d9c04453a083a6938 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-13T15:08:59Z (GMT) No. of bitstreams: 1 GuilhermePaimMascarenhas_DISSERT.pdf: 2944281 bytes, checksum: 438ec06a374cf17d9c04453a083a6938 (MD5) / Made available in DSpace on 2018-03-13T15:08:59Z (GMT). No. of bitstreams: 1 GuilhermePaimMascarenhas_DISSERT.pdf: 2944281 bytes, checksum: 438ec06a374cf17d9c04453a083a6938 (MD5) Previous issue date: 2017-08-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Embora normalmente associada a meios de transporte, a mobilidade ? uma caracter?stica fundamental da vida do ser humano e pode ser expressa de diversas maneiras. A circula??o humana pelos espa?os ? uma das possibilidades de mobilidade, que mudou desde o advento do autom?vel. Enquanto as cidades criaram espa?os para os carros, a ind?stria automotiva, que enfrentava uma p?ssima reputa??o no in?cio dos anos 20, tanto introduziu a ideia do pedestre imprudente quanto naturalizou os acidentes de tr?nsito. O uso da bicicleta n?o escapa desta l?gica, que responsabiliza os mais vulner?veis. Diante deste cen?rio, o objetivo geral deste estudo ? investigar a rela??o dos usu?rios de bicicleta com os aspectos ambientais e normativos do tr?nsito urbano. O presente trabalho possui car?ter explorat?rio e aplicou diferentes t?cnicas de produ??o de dados devido ? complexidade do objeto, em duas etapas: 1) mapeamento comportamental centrado no lugar; 2) o mapeamento comportamental centrado na pessoa e a entrevista com base em v?deos. Os dados revelaram algumas das formas de rela??o: uso obrigat?rio ou opcional do capacete, discursos sobre o c?digo de tr?nsito, linguagem corporal durante o ciclismo e os comportamentos que n?o seguiram os padr?es. Os resultados demonstraram que os ambientes do tr?nsito fazem com que os ciclistas adotem movimentos que, por vezes, v?o de encontro ao C?digo de Tr?nsito Brasileiro. / Although usually associated with means of transport, mobility is a fundamental characteristic of human life and may be expressed in many ways. Human movement through spaces is one of the possible ways of mobility, which changed since the advent of the automobile. While cities made room for cars, the automobile industry, facing a bad reputation in the early 1920s, both introduced the idea of reckless pedestrian and naturalized traffic accidents. The use of bicycle does not escape such logic, which blames the most vulnerable individuals. Given this scenario, the general objective of this study is to investigate the relationship between bicycle users and the environmental and normative aspects of urban traffic. The present work has an exploratory character and applied different techniques of data production due to the complexity of the object, in two stages: 1) place-centered behavioral mapping; 2) person-centered behavioral mapping and interview based on video recordings. The data revealed some forms of relationship: compulsory or optional use of helmet, discourses about the traffic code, body language during cycling and behaviors that do not follow the standards. The results demonstrated that the traffic environments make cyclists adopt movements that sometimes oppose the Brazilian Traffic Code.
113

A influência do padrão de adensamento nas características de um escoamento urbano : uma aplicação à região do Altiplano Cabo Branco em João Pessoa-PB / The influence of the pattern and process of densification in the characteristics of an urban runoff : an application of the region of Altiplano Cabo Branco in João Pessoa-PB

Peregrino, Paulo Sérgio Araújo January 2014 (has links)
Faz-se notória a ideia de que o crescimento das cidades e o consequente aumento no adensamento das mesmas é, nos dias atuais, um fato inevitável; e que o homem, ao modificar o meio natural, o faz quase sempre de forma danosa. Formação de ilhas de calor, aumento do consumo de energia, dificuldade na dispersão de poluentes, diminuição do ângulo de visão do céu, diminuição da taxa de permeabilidade do solo entre outros, são problemas frequentemente relacionados com a densificação e verticalização das cidades. A utilização de modelos reduzidos para simulações experimentais em túneis de vento das condições naturais de ventilação se mostram eficazes, além de reduzir custos em pesquisas nesta área. Embasando-se em tais pressupostos, o presente trabalho pretende verificar as alterações das características dos escoamentos de vento provocadas por distintos padrões de ocupação do solo urbano no bairro do Altiplano Cabo Branco, na cidade de João Pessoa-PB. A área em estudo atravessa um processo acelerado de modificação nas suas características de ocupação urbana, conduzido pelas alterações dos indicadores urbanísticos locais, antes mais restritivos, possibilitando agora edificações com gabaritos em altura significativamente maiores do que os anteriormente observados no local. Parte-se então da hipótese de que o processo de verticalização resultante deste crescimento é capaz de alterar os escoamentos de ventos não apenas nas áreas onde este ocorre, mas também em áreas contíguas. No desenvolvimento deste trabalho, de caráter experimental, foram avaliados dois modelos de adensamentos urbanos para a área de estudo O primeiro deles reproduz a ocupação da área conforme se encontrava antes de mudanças ocorridas nos indicadores urbanísticos para o local. O segundo apresenta a configuração atual de ocupação da área, delineada pela legislação em vigor. Para viabilizar esta avaliação serão realizados ensaios no Túnel de Vento de retorno fechado, Professor Joaquim Blessmann, do Laboratório de Aerodinâmica das Construções da Universidade Federal do Rio Grande do Sul, utilizando maquetes (modelos) em escala reduzida e observando os requerimentos necessários estabelecidos para este padrão de estudo experimental. Foram utilizados nos ensaios para cada uma das duas configurações de vizinhança dois ângulos de ataque de vento, 150 e 90 graus, tomando como referência o atlas de vento do local de estudo. A partir da análise dos resultados obtidos é possível concluir que a verticalização, da maneira como propõe legislação atual para a área, não apresenta perdas significativas no que se refere aos escoamentos (ventos) quando comparada com o padrão de ocupação anterior sem os edifícios altos. As áreas adjacentes também não sofrem maiores prejuízos no que se refere aos escoamentos quando comparados os dois modelos. / What is worth elucidating is the idea about city expansion and consequent increasing effects of the densification is, now are days, an unavoidable fact; and that human, by modifying the natural environment, does so always in a destructive way. Formation of heat island, increase of the energy consumption, difficulty in the dispersion of pollutants, reduction in the sky view angle, diminution of the level of soil permeability among others, are problem frequently related to densification and verticalization of cities. The use of reduced models for experimental simulation in wind tunnel considering natural conditions of ventilation prove to be effective, apart from low down cost of experiments in this area of research. Based on such assumption, the aim of this research was to verify the alterations of wind flow characteristics provoked on distinct occupation pattern of urban soil in the district of Altiplano Cabo Branco, in the city of João Pesssoa-PB. The studied site passed through a fast process of physical modification in its urban occupation characteristics, conducted by local urban indicators, which was earlier more restrictive, presently permitting building with considerable standard that are higher than those, which were formerly observed on site. Based on the assumption that the process of verticalization as a product of growth may alter the wind flow not only in the areas where it occurs but also in adjacent areas In developing this work, experimentally, two models of urban concentrations were examined on the study area. The first was reproduced on the occupation of the area as it was founded before the changes in the local urban indicators. The second shows the current configuration of occupation of the area outlined by the current legislation. To make this assessment tests were carried out in the Boundary layer wind tunnel, Professor Joaquim Blessmann, of Federal University of Rio Grande do Sul, by use of model building of reduced scale and observing the necessary requirements established for this standard experimental study. Two angles of attack of wind were utilized in the two experiments, 150 and 90 degrees, with reference to the wind atlas of site of study. From the result of this analysis we conclude that virtualization of the occupation proposed by the current proposed legislation for the site does not present significant losses when compared with the previous standard of occupation lacking the tall buildings. Adjacent areas do not affected by losses in relation to the wind flow of the two models that was compared.
114

Dinâmica de configuração de regras para inovação : um olhar complexo e interteórico numa organização de pesquisa agrícola do agronegócio orizícola do Rio Grande do Sul

Dias, Marcelo Fernandes Pacheco January 2011 (has links)
Dois temas são característicos do contexto atual das organizações. Um, já consolidado, é o aumento da velocidade das inovações; o outro, é a necessidade de incorporar a perspectiva emergente da sustentabilidade nas práticas de inovação. A Teoria Neoschumpeteriana busca obter um domínio desses fenômenos dinâmicos da realidade econômica, em que a inovação, principalmente a tecnológica, é identificada como a força maior que propulsiona a dinâmica econômica. Entretanto, Hanusch e Pyka (2007) criticam a Teoria Neoschumpeteriana por entenderem que o desenvolvimento dos sistemas econômicos modernos incorpora a inovação tecnológica, assim como também a inovação organizacional, institucional e social e, por isso, os novos frameworks para estudos de sistemas econômicos, precisariam incorporar características de complexidade através do trânsito em diferentes teorias relevantes, levando em conta as raízes da Teoria Neoschumpeteriana, o que eles próprios não fazem. Assim, o objetivo geral de pesquisa foi o de propor um framework interteórico e complexo sobre a dinâmica da inovação e fazer a sua aplicação no Instituto Rio-Grandense do Arroz - IRGA. A metodologia utilizada foi de estudo de caso. Os dados foram coletados através de entrevistas e documentos. Cada uma das etapas realizadas na metodologia foi apoiada num estudo, a priori, sobre métodos que capturavam características de complexidade. A utilização de uma lógica abdutiva, prevista na metodologia, com constantes idas e vindas entre os conceitos teóricos construídos a priori e as informações advindas do campo empírico, fez emergir o conceito teórico de sistema econômico, como uma configuração complexa de múltiplos níveis de regras que se relacionam ao longo do tempo e se sucedem. Neste sentido, a presente pesquisa avançou ao identificar a emergência de regras, oriunda das teorias usadas, como uma qualidade nova e central, que em múltiplos níveis, compõe as configurações, que evoluem ao longo do tempo. Este avanço possibilitou estudar a história econômica do IRGA, não da perspectiva operacional, mas da perspectiva das regras genéricas, de maior nível, e das regras de menor nível associadas à regra genérica, numa perspectiva de configurações dinâmicas que evoluem, focado em inovações. A lógica abdutiva possibilitou avanços metodológicos na aplicação do método de análise qualitativa comparativa (QCA) no estudo das dinâmicas de configurações, já que o método tinha até então, sido aplicado numa abordagem estática. Os resultados indicaram, ainda, a presença de cinco regras genéricas no contexto de pesquisa do IRGA. O IRGA inseriu predominantemente, em suas atividades, de pesquisa a regra genérica de mais produtividade agrícola. As regras genéricas de gestão ambiental da propriedade agrícola, aumento do consumo do arroz, aumento da renda para o produtor foram inseridas nas atividades de pesquisa de modo marginal. A regra genérica denominada de negócios ambientais nas beneficiadoras de arroz ainda não foi inserida nas atividades de pesquisa do IRGA. A dinâmica de inserção destas regras genéricas no IRGA ocorre através de oito configurações de regras de nível zero e de segunda ordem, que seguem um conjunto de fases que foram denominadas de pré-distúrbio, origem, adoção, retenção e declínio. Uma característica nesta dinâmica é de que somente ocorreu a mudança de fase da regra genérica quando determinadas regras de segundo e de ordem zero estavam presentes. Como as fases de evolução das regras genéricas ocorreram em diferentes anos, no período entre 1969 e 2009, a combinação destas fases gerou seis configurações temporais de regras para inovação no IRGA. / Two themes are characteristic of the organizations on the current context. One is already established that is the increasing innovations speed. The other one is the need to incorporate the sustainability‘s emerging perspective in innovation practices. The Neo-Schumpeterian Theory seeks to obtain a domain on these dynamic phenomena of the economic reality, in which the innovation, especially technological, is identified as its greater propellent force. However, Hanusch and Pyka (2007) criticize the Neo-Schumpeterian Theory for understanding that the development of modern economic systems incorporate the technological innovation, as well as the organizational innovation, institutional, and social. Therefore, the new frameworks for the economic systems studies would need to incorporate some complexity features through traffic in different and relevant theories, taking into account the Neo-schumpeterian Theory roots, which they themselves do not do. Thus, the overall objective of this research was to propose an inter-theoretical and complex framework on the innovation dynamics and to make its application at the IRGA (Instituto Rio-Grandense de Arroz - Rice Institute of Rio Grande do Sul State, Brazil). We used the case study methodology. Data were collected by some interviews and from some documents. Each of the used methodology steps was supported in a priori study on methods that captured the complexity characteristics. The economic system‘s theoretical concept as a complex configuration of the multiple rules levels related over the time, and that succeed itself, came from an abductive logic use from the methodology, with constant goings and comings among the theoretical concepts a priori constructed, and from the empirical information from the field. In this sense, this research has advanced when identified the rules emergence, derived from the used theories as a new quality and centered, which at multiple levels composes the configurations that evolve over the time. This advance allowed the IRGA‘s economic history study, not from the operational perspective, but from the general rules perspectives of highest level and from the lowest level associated with the general rules perspectives, at a dynamic configurations perspective that evolve focusing on innovations. The abductive logic allowed the methodological advances in the method application of comparative and qualitative analysis (CQA) in the study of the configurations dynamics, since the method had until then been applied on a static approach. The results also indicated the presence of five generic rules in the context of the IRGA research. The IRGA inserted predominantly the general rule of most agricultural productivity in its research activities. The general rules of the farm environmental management, the increased rice consumption, and the increased income for producers have been included in the research activities marginally. The general rule of environmental affairs in the rice processing has not been incorporated into the IRGA research activities. The insertion dynamic of these general rules occurs through eight rules of level zero and second order configurations, which follow a stages set that were identified as pre-disturbance, origin, adoption, retention, and decay. A dynamic characteristic is that there was only a phase change of the general rule when certain rules of the second and zero order were present. As the phases of the generic rules development occurred in different years, from 1969 to 2009, these phases combination generated six rules temporal configurations for innovation in the IRGA.
115

A Personalized Car : A study on how to apply personalization to a driver environment

Ericsson, Tomas, Nilqvist, Monika January 2006 (has links)
An increasing amount of technology in cars makes new ideas and solutions necessary. This study will explore the idea of a personalized driver environment and investigate possible benefits and drawbacks with such a feature. The study consists of three parts: a pre-study exploring personalization, a survey investigating the attitudes towards personal settings, and finally an interview testing a specific solution. The survey was distributed in USA and Sweden while the interviews were conducted with Swedish subjects. Overall, the concept of a personalized car has been well received. This study has shown that the most requested settings are associated with the driver position, hi-fi system and climate. The study also suggests that feeling in control of the personalization is more important than the benefits associated with automation. The user prefers visible solutions, such as a personal button on the key before hidden (e.g. using a button sequence or a menu system). Such a button promotes the feature while allowing the user to interact with the car in a familiar way. However, since little real user experience exists with such solutions it is important to continue research when further developing personalization of a car.
116

Keys to Effectively Create Realistic Fur in Autodesk Maya

Normann, Annica January 2012 (has links)
The tools for creating realistic fur using a computer have continued to develop sincethe first computer-generated fur was accomplished. Tools for creating fur can befound inside of the software Autodesk Maya. Rendering fur is often a very timeconsuming process and therefore this thesis investigates how the relationship ofrealistic fur versus render time can be improved. When creating fur, there are severalaspects to take into account, for example shadowing, length, color and irregularities.This thesis assesses the question through a case study and includes experimentalresearch which was attempted simultaneously. It valuates the results through asurvey. The qualitative research does not include animated fur, only still images ofcomputer-generated fur. This research will hopefully improve the knowledge and actas a guide for others who are creating fur.
117

The Sneetches

Schneider, Gregory Alan 12 1900 (has links)
The Sneetches is a theater piece for children based on the Dr. Suess story The Sneetches (Random House, New York, 1961). It is scored for narrator, flute, B6 clarinet, bassoon, violins I & II, viola, and cello with optional staging. The staged version of The Sneetches requires two to six actors/dancers, appropriate scenery and props, and the active participation of children from the audience, preferably ages eight or under. The Sneetches is essentially through-composed. The overall form of the music is shaped primarily by the events portrayed in the narrative. Although individual subsections may have traditional forms, they should not be viewed as independent movements of a larger work, but rather as fragments of a whole.
118

An Evaluation of An Assessment of Check-In/Check-Out with Children who are Homeless in an After School Care Program

Camacho, Ana Paula 29 June 2016 (has links)
Schoolwide Positive Behavior Interventions and Support (SWPBIS) is an approach designed to improve the correct implementation, consistent use, and maintenance of evidence-based practices related to behavior, classroom management and school discipline systems. Check-in/Check-out (CICO) is often recognized as a successful intervention in SWPBIS. However, most of the research on the use of CICO has focused on the school setting. This study provided an extension to the literature by examining the effects of the CICO program with homeless children attending an afterschool program. A non-concurrent multiple baseline across participants design was used to evaluate the CICO program effects. Students were exposed to a CICO intervention in which problem behaviors were targeted for reduction and task engagement was targeted for acquisition. Of the five participants selected for the study four participants were exposed to a CICO intervention. Results demonstrated a decrease in problem behaviors and an increase in task engagement for all four participants.
119

Analysis of energy based signal detection

Lehtomäki, J. (Janne) 29 November 2005 (has links)
Abstract The focus of this thesis is on the binary signal detection problem, i.e., if a signal or signals are present or not. Depending on the application, the signal to be detected can be either unknown or known. The detection is based on some function of the received samples which is compared to a threshold. If the threshold is exceeded, it is decided that signal(s) is (are) present. Energy detectors (radiometers) are often used due to their simplicity and good performance. The main goal here is to develop and analyze energy based detectors as well as power-law based detectors. Different possibilities for setting the detection threshold for a quantized total power radiometer are analyzed. The main emphasis is on methods that use reference samples. In particular, the cell-averaging (CA) constant false alarm rate (CFAR) threshold setting method is analyzed. Numerical examples show that the CA strategy offers the desired false alarm probability, whereas a more conventional strategy gives too high values, especially with a small number of reference samples. New performance analysis of a frequency sweeping channelized radiometer is presented. The total power radiometer outputs from different frequencies are combined using logical-OR, sum and maximum operations. An efficient method is presented for accurately calculating the likelihood ratio used in the optimal detection. Also the effects of fading are analyzed. Numerical results show that although sweeping increases probability of intercept (POI), the final probability of detection is not increased if the number of observed hops is large. The performance of a channelized radiometer is studied when different CFAR strategies are used to set the detection threshold. The proposed iterative methods for setting the detection threshold are the forward consecutive mean excision (FCME) method with the CA scaling factors in final detection decision (FCME+CA), the backward consecutive mean excision (BCME) method with the CA scaling factors in detection (BCME+CA) and a method that uses the CA scaling factors for both censoring and detection (CA+CA). Numerical results show that iterative CFAR methods may improve detection performance compared to baseline methods. Finally, a method to set the threshold of a power-law detector that uses a nonorthogonal transform is presented. The mean, variance and skewness of the decision variable in the noise-only case are derived and these are used to find a shifted log-normal approximation for the distribution of the decision variable. The accuracy of this method is verified through simulations.
120

Stroke rehabilitation outcomes in hebron - Palestine

Amro, Akram January 2013 (has links)
Philosophiae Doctor - PhD / Aim: To investigate strokes, epidemiology, stroke characteristics, use of care and rehabilitation outcomes, and factors predicting these outcomes in stroke patients in Hebron city, in southern Palestine. Design: A one-year hospital-based, observational, descriptive, case-control, cohort study. Sample: One hundred and thirty nine (139) stroke patients were recruited from two main hospitals in Hebron city (Alia and Al-Ahli hospitals). Procedure: Objective assessment, patient interview, file screening and observation of the recruited cases was performed, risk factors were recorded and impairment, functional activity and participation were captured at baseline (T1), three months (T2), and six months (T3).

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