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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

Učitelovo pojetí učiva o rodině / Teacher' s approach to family related curriculum

Plavcová, Veronika January 2011 (has links)
My diploma thesis focuses on the approach to family related curriculum at primary school. The theoretical part includes analysis of contemporary view of family in terms of psychology and sociology, summary of possible problems connected with the family related curriculum, some recommendations how to approach the family related curriculum and analysis of approach to this curriculum in FEP EE, three school education programmes and three sets of textbooks from primary education. The practical part examines the approach to family related curriculum from students' of teaching point of view.
112

Eficiência energética e espectral em sistemas de comunicação sem fio: diversidade cooperativa, espacial e em frequência. / Energy and spectral efficiency in wireless communication systems: cooperative, spacial and frequency diversities.

Castro e Souza, Alvaro Ricieri 10 May 2018 (has links)
Sistemas modernos de comunicação móvel sem fio, como os de quarta geração (4G), têm como principais metas prover elevada capacidade e alta qualidade de serviço (QoS) para os usuários. Para prover tal aumento de capacidade e QoS, sistemas 4G empregam diversas técnicas avançadas de transmissão e maior largura de banda, combinados com algoritmos de alocação de recursos que possam explorar de maneira eficiente tais técnicas, como por exemplo aproveitando as dimensões de diversidade do sistema. Em geral, porém, é necessário também aumentar a potência de transmissão para se atingir o ganho de capacidade desejado, o que implica maior custo para os provedores de serviço, menor tempo de vida para os dispositivos móveis e impacto ambiental cada vez mais pronunciado. Dado que a expectativa é que o número de usuários e a necessidade de dados continuem crescendo rapidamente, torna-se evidente a importância de analisar a relação entre capacidade e potência dispendida pelo sistema. Essa relação pode ser vista através da métrica de eficiência energética (EE), que é dada pela razão entre o número de bits efetivamente recebidos e a energia consumida no processo, revelando quão eficientemente o sistema transforma a energia consumida em informação efetivamente recuperada no receptor. Um sistema otimizado em relação à EE é capaz de transmitir mais informação por unidade de energia consumida, resultando em utilização mais racional e eficiente dos escassos recursos energéticos. Uma segunda questão acerca das metas é em relação à distribuição dos ganhos de capacidade/ QoS pela célula, i.e., quais usuários serão capazes de usufruir da maior capacidade e QoS. Em ambientes macrocelulares urbanos, a perda de percurso pode chegar a várias dezenas de decibéis em distâncias relativamente pequenas, além dos obstáculos naturais, como relevo, e artificiais, como prédios, o que limita ainda mais o desenvolvimento de sistemas energeticamente eficientes. Em abordagens tradicionais, tais problemas exigem a utilização de potências elevadas, em geral superiores à potência que os dispositivos podem utilizar, ou então requerem o aumento da densidade de estações rádio-base (BSs), o que geralmente resulta em custos inviáveis do ponto de vista dos operadores. Assim, busca-se em sistemas 4G emular o aumento da densidade de BSs através do conceito de redes heterogêneas, que são células com menor área de cobertura instaladas em pontos críticos de cobertura da célula original, como por exemplo a região de borda de célula, atendendo de maneira eficiente os usuários. No cenário de redes heterogêneas, um dos principais paradigmas é o conceito de redes cooperativas, no qual estações retransmissoras (RSs) reenviam o sinal recebido da estação fonte para estação destino, reduzindo a potência consumida com o canal móvel sem fio. Como utilizam conexão sem fio com a BS, as RSs podem ser instaladas em regiões com pouca infraestrutura sem a necessidade de grandes modificações, resultando em implantações bastante flexíveis. Assim, este trabalho de doutorado visa investigar estratégias de alocação de recursos baseadas no incremento da eficiência energética para sistemas celulares de quarta e quinta gerações utilizando o paradigma de redes cooperativas, determinando potencialidades e também itens que necessitam ser modificados, otimizados ou mesmo redefinidos, tendo em vista um aumento substancial da eficiência energética global da rede de comunicação sem fio. Busca-se durante o desenvolvimento do modelo de sistema capturar e quantificar as principais características de importantes sistemas celulares em uso atualmente, i.e., LTE-A e WiMAX, de modo que as decisões de design considerem os esforços de padronização, porém não se limitem a eles. Como a abordagem de alocação de recursos baseada em EE pode impactar nas métricas de desempenho do sistema, investiga-se também o compromisso entre as eficiências energética e espectral (SE), de modo que o aumento da EE não seja causado apenas pela degradação da SE e que seja possível obter maior EE para uma mesma SE e QoS. / Modern wireless communication systems, such as the fourth generation (4G) ones, have as main objectives to provide high capacity and quality of service (QoS) for the users. In order to provide such capacity and QoS gain, 4G systems use several advanced transmission techniques and higher bandwidth, combined with resource allocation algorithms that are able to efficiently exploit such techniques, as for example taking advantage of the diversity dimensions of the system. Generally, however, it is also necessary to increase the transmission power to achieve the desired capacity gain, which implies increased costs for service providers, shorter lifetime for the mobile devices and increasingly pronounced environmental impact. Since the expectation is that the number of users and data necessity will continue growing rapidly, it is evident the importance of analyzing the relation between capacity and power expended by the system. This relation can be seen through the energy efficiency (EE) metric, which is given by the ratio between the number of effectively received information bits and the energy consumed in the transmission process, revealing how efficiently the system transform consumed energy into effectively recovered information at the receiver. A system optimized regarding EE is able to transmit more information per unit of energy consumed, resulting in a more rational and efficient utilization of the scarce energetic resources. A second issue is relative to the distribution of the capacity/QoS gains over the whole cell, i.e, which users will be able to take advantage of the higher capacity and QoS. In urban macrocellular environments, the path-loss can reach several tens of decibels in relatively short distances, in addition to natural obstacles, such as land relief, or artificial, such as buildings, which further limits the development of energetically efficient systems. In traditional approaches, such problems require the use of high transmission power, generally greater than the power that the devices can use, or else require increased density of base-stations (BSs), which generally results in unviable costs from the operators point of view. Thus, in 4G systems it is sought to emulate the increase in the density of BSs through the concept of heterogeneous networks, which are cells with smaller coverage area installed in critical points of the original macrocell coverage, as for example the cell-edge area, serving efficiently the users. In the heterogeneous networks scenario, one of the main paradigms is the concept of cooperative networks, in which relay stations (RSs) retransmit the signal received from the source station to the destination station, reducing the power consumed with the mobile wireless channel. As the RSs use a wireless connection to the BS, they can be installed in places with poor infrastructure without requiring major modifications, resulting in very flexible deployments. Thus, this PhD work aims to investigate resource allocation strategies based on the improvement of the energy efficiency for fourth and fifty generation cellular systems using the cooperative networks paradigm, determining potentialities and also items that need to be modified, optimized or even redefined, aiming to a substantial increase in the overall energy efficiency of the wireless communication network. It is sought during the development of the system model to capture and quantify the main features of important cellular systems currently in use, i.e., LTE-A and WiMAX, so that the design decisions consider the standardization efforts, but do not be limited by them. Since the EE-based resource allocation approach can impact the performance metrics of the system, it will be investigated also the tradeoff between energy and spectral (SE) efficiencies, so that the increase in energy efficiency is not caused by degradation of the SE and also to be possible to obtain a higher EE for a same SE and QoS.
113

Eficiência energética e espectral em sistemas de comunicação sem fio: diversidade cooperativa, espacial e em frequência. / Energy and spectral efficiency in wireless communication systems: cooperative, spacial and frequency diversities.

Alvaro Ricieri Castro e Souza 10 May 2018 (has links)
Sistemas modernos de comunicação móvel sem fio, como os de quarta geração (4G), têm como principais metas prover elevada capacidade e alta qualidade de serviço (QoS) para os usuários. Para prover tal aumento de capacidade e QoS, sistemas 4G empregam diversas técnicas avançadas de transmissão e maior largura de banda, combinados com algoritmos de alocação de recursos que possam explorar de maneira eficiente tais técnicas, como por exemplo aproveitando as dimensões de diversidade do sistema. Em geral, porém, é necessário também aumentar a potência de transmissão para se atingir o ganho de capacidade desejado, o que implica maior custo para os provedores de serviço, menor tempo de vida para os dispositivos móveis e impacto ambiental cada vez mais pronunciado. Dado que a expectativa é que o número de usuários e a necessidade de dados continuem crescendo rapidamente, torna-se evidente a importância de analisar a relação entre capacidade e potência dispendida pelo sistema. Essa relação pode ser vista através da métrica de eficiência energética (EE), que é dada pela razão entre o número de bits efetivamente recebidos e a energia consumida no processo, revelando quão eficientemente o sistema transforma a energia consumida em informação efetivamente recuperada no receptor. Um sistema otimizado em relação à EE é capaz de transmitir mais informação por unidade de energia consumida, resultando em utilização mais racional e eficiente dos escassos recursos energéticos. Uma segunda questão acerca das metas é em relação à distribuição dos ganhos de capacidade/ QoS pela célula, i.e., quais usuários serão capazes de usufruir da maior capacidade e QoS. Em ambientes macrocelulares urbanos, a perda de percurso pode chegar a várias dezenas de decibéis em distâncias relativamente pequenas, além dos obstáculos naturais, como relevo, e artificiais, como prédios, o que limita ainda mais o desenvolvimento de sistemas energeticamente eficientes. Em abordagens tradicionais, tais problemas exigem a utilização de potências elevadas, em geral superiores à potência que os dispositivos podem utilizar, ou então requerem o aumento da densidade de estações rádio-base (BSs), o que geralmente resulta em custos inviáveis do ponto de vista dos operadores. Assim, busca-se em sistemas 4G emular o aumento da densidade de BSs através do conceito de redes heterogêneas, que são células com menor área de cobertura instaladas em pontos críticos de cobertura da célula original, como por exemplo a região de borda de célula, atendendo de maneira eficiente os usuários. No cenário de redes heterogêneas, um dos principais paradigmas é o conceito de redes cooperativas, no qual estações retransmissoras (RSs) reenviam o sinal recebido da estação fonte para estação destino, reduzindo a potência consumida com o canal móvel sem fio. Como utilizam conexão sem fio com a BS, as RSs podem ser instaladas em regiões com pouca infraestrutura sem a necessidade de grandes modificações, resultando em implantações bastante flexíveis. Assim, este trabalho de doutorado visa investigar estratégias de alocação de recursos baseadas no incremento da eficiência energética para sistemas celulares de quarta e quinta gerações utilizando o paradigma de redes cooperativas, determinando potencialidades e também itens que necessitam ser modificados, otimizados ou mesmo redefinidos, tendo em vista um aumento substancial da eficiência energética global da rede de comunicação sem fio. Busca-se durante o desenvolvimento do modelo de sistema capturar e quantificar as principais características de importantes sistemas celulares em uso atualmente, i.e., LTE-A e WiMAX, de modo que as decisões de design considerem os esforços de padronização, porém não se limitem a eles. Como a abordagem de alocação de recursos baseada em EE pode impactar nas métricas de desempenho do sistema, investiga-se também o compromisso entre as eficiências energética e espectral (SE), de modo que o aumento da EE não seja causado apenas pela degradação da SE e que seja possível obter maior EE para uma mesma SE e QoS. / Modern wireless communication systems, such as the fourth generation (4G) ones, have as main objectives to provide high capacity and quality of service (QoS) for the users. In order to provide such capacity and QoS gain, 4G systems use several advanced transmission techniques and higher bandwidth, combined with resource allocation algorithms that are able to efficiently exploit such techniques, as for example taking advantage of the diversity dimensions of the system. Generally, however, it is also necessary to increase the transmission power to achieve the desired capacity gain, which implies increased costs for service providers, shorter lifetime for the mobile devices and increasingly pronounced environmental impact. Since the expectation is that the number of users and data necessity will continue growing rapidly, it is evident the importance of analyzing the relation between capacity and power expended by the system. This relation can be seen through the energy efficiency (EE) metric, which is given by the ratio between the number of effectively received information bits and the energy consumed in the transmission process, revealing how efficiently the system transform consumed energy into effectively recovered information at the receiver. A system optimized regarding EE is able to transmit more information per unit of energy consumed, resulting in a more rational and efficient utilization of the scarce energetic resources. A second issue is relative to the distribution of the capacity/QoS gains over the whole cell, i.e, which users will be able to take advantage of the higher capacity and QoS. In urban macrocellular environments, the path-loss can reach several tens of decibels in relatively short distances, in addition to natural obstacles, such as land relief, or artificial, such as buildings, which further limits the development of energetically efficient systems. In traditional approaches, such problems require the use of high transmission power, generally greater than the power that the devices can use, or else require increased density of base-stations (BSs), which generally results in unviable costs from the operators point of view. Thus, in 4G systems it is sought to emulate the increase in the density of BSs through the concept of heterogeneous networks, which are cells with smaller coverage area installed in critical points of the original macrocell coverage, as for example the cell-edge area, serving efficiently the users. In the heterogeneous networks scenario, one of the main paradigms is the concept of cooperative networks, in which relay stations (RSs) retransmit the signal received from the source station to the destination station, reducing the power consumed with the mobile wireless channel. As the RSs use a wireless connection to the BS, they can be installed in places with poor infrastructure without requiring major modifications, resulting in very flexible deployments. Thus, this PhD work aims to investigate resource allocation strategies based on the improvement of the energy efficiency for fourth and fifty generation cellular systems using the cooperative networks paradigm, determining potentialities and also items that need to be modified, optimized or even redefined, aiming to a substantial increase in the overall energy efficiency of the wireless communication network. It is sought during the development of the system model to capture and quantify the main features of important cellular systems currently in use, i.e., LTE-A and WiMAX, so that the design decisions consider the standardization efforts, but do not be limited by them. Since the EE-based resource allocation approach can impact the performance metrics of the system, it will be investigated also the tradeoff between energy and spectral (SE) efficiencies, so that the increase in energy efficiency is not caused by degradation of the SE and also to be possible to obtain a higher EE for a same SE and QoS.
114

Systèmes MIMO précodés optimisant la distance minimale : étude des performances et extension du nombre de voies

Vrigneau, Baptiste 23 November 2006 (has links) (PDF)
Les systèmes multi-antennaires (Multiple-Input Multiple-Ouput ou MIMO) dans le domaine des communications numériques permettent d'améliorer la transmission des données selon deux principaux paramètres souvent antagonistes : le débit d'information et la fiabilité de transmission estimée en terme de probabilité d'erreurs binaire moyenne (PEB). Avec de tels systèmes, la connaissance du canal à l'émission (Channel State Information ou CSI) est un point-clé pour diminuer la PEB grâce à différentes stratégies d'allocations de puissance. Ainsi, un précodeur linéaire à l'émission associé à un décodeur linéaire à la réception peuvent optimiser un critère particulier grâce à cette information. Il en résulte une famille importante de précodeurs dénommée «précodeurs diagonaux» : le système MIMO est équivalent à des sous-canaux SISO indépendants. Les critères optimisés sont par exemple la minimisation de l'erreur quadratique moyenne (EQMM), la maximisation de la capacité (WF), obtenir des PEB égales pour tous les flux de données (EE), la maximisation du RSB post-traitement (max-SNR) ou la qualité de service (QdS). L'équipe TST a récemment élaboré un nouveau précodeur non diagonal basé sur la maximisation de la distance minimale entre symboles de la constellation de réception (max-dmin ). L'enjeu de cette thèse est d'estimer les performances en terme de PEB de ce nouveau précodeur et de les comparer avec les méthodes existantes à savoir le code d'Alamouti et les précodeurs diagonaux. Nous nous sommes intéressés en particulier à la démonstration de l'ordre de diversité maximal du max-dmin puis à la détermination d'une bonne approximation de sa PEB. Le précodeur max-dmin est ensuite associé à de la diversité de polarisation permettant de réduire le coût et l'occupation spatiale d'un système MIMO. Malgré l'introduction de corrélation, les performances proposées par le max-dmin demeurent intéressantes. Nous avons ensuite proposé une extension du précodeur max-dmin permettant de supprimer la limitation à deux sous-canaux : les grands systèmes MIMO sont mieux exploités avec plus de deux sous-canaux.
115

License Management for EBITool

Krznaric, Anton January 2013 (has links)
This degree project deals with license management for EBITool. It´s about providing protection and monitoring for a Java Application via a license server, and the construction of it. An analysis that discusses the approach and other possible courses of action is also included. Additionally, it covers a discussion of a prototype implementation of the model solution from the analysis. The prototype is a Java EE application that deploys to JBoss AS7. It´s developed using the JBoss Developer Studio 5.0.0, an Eclipse IDE with JBoss Tools preinstalled. It exposes web services to Java Applications through SOAP via JAX-WS. Using Hibernate, the web service Enterprise Java Beans get access to a PostgreSQL 9.1 database via entity classes mapped to the database through the Java Persistence API.
116

A comparative study of burnout among teachers in a Youth Juvenile Rehabilitation center, an Ex model C school, and Public schools

Clayford, Mario January 2010 (has links)
<p>This study examined three schools / namely a Public, Ex model C, and a Youth juvenile rehabilitation school. A non-experimental survey design was used for this study. The sample consisted of 47 educators across the three types of schools. Data was collected by means of two instruments: a demographic questionnaire, and the Maslach Burnout Inventory (MBI) consisting of three subscales namely / Emotional Exhaustion, Depersonalization, and Diminished Personal Accomplishment. It was hypothesised that due to the stressful nature of work in disadvantaged and resource lacking schools, as well as the unstable and unsafe environment in certain schools, burnout among educators in Public and Youth juvenile rehabilitation schools will have a higher prevalence rate than educators in Ex model C schools. The study also aimed to identify which various educator demographic variables correlate with high burnout levels. Correlational results of the study found no significant relationships between the three subscales of the MBI and certain educator demographic variables across the three types of schools. The results of an Analysis of Variance (ANOVA) test revealed a borderline non-significant difference in the Emotional Exhaustion subscale between the Youth juvenile rehabilitation school and Public schools. Post Hoc comparison tests suggested Public school educators in the sample had the highest levels of burnout in terms of Emotional Exhaustion across the three types of schools, while educators in the Youth juvenile rehabilitation schools showed the lowest levels of burnout in terms of Emotional exhaustion. The results of the present study were discussed from the perspective of the Conservation of Resources theory, suggesting resource depletion as a central facet to burnout and how prolonged stress leads to burnout. Future qualitative studies exploring the etiology of burnout was thus recommended.</p>
117

Traitement de Requêtes Top-k dans les Communautés Virtuelles P2P de Partage de Données

Dedzoe, William Kokou 30 November 2011 (has links) (PDF)
Dans les communautés virtuelles pair-à-pair (P2P) de partage de données, les requêtes top-k présentent deux avantages principaux. Premièrement, elles permettent aux participants de qualifier les résultats de leurs requêtes par rapport aux données partagées dans le système et ceci en fonction de leurs préférences individuelles. Deuxièmement, elles évitent de submerger les participants avec un grand nombre de réponses. Cependant, les techniques existantes pour le traitement des requêtes top-k dans un environnement complètement distribué présentent l'inconvénient d'un temps d'attente important pour l'utilisateur. Ce temps d'attente est encore très long plus le système est surchargé. Dans un premier temps, nous revisitons le problème du temps d'attente de l'utilisateur dans le traitement des requêtes top-k en introduisant deux nouvelles mesures : le temps de stabilisation et la qualité restante cumulée. En complément des mesures existantes, elles permettent de qualifier plus précisément le comportement d'un algorithme top-k. Dans un deuxième temps, nous proposons une famille d'algorithmes (ASAP), permettant de retourner à l'utilisateur les résultats de bonne qualité le plus tôt possible. Enfin, nous nous intéressons au problème du traitement des requêtes top-k dans le cadre des systèmes P2P surchargés, particulièrement critique pour les solutions classiques, en proposant une nouvelle approche (QUAT). Cette solution fait usage de descriptions synthétiques des données des pairs pour permettre aux pairs de traiter en priorité les requêtes pour les quelles ils peuvent fournir des résultats de bonne qualité.
118

Systém správy identit pro malé a střední firmy / Identity Management Solution for Small and Medium Businesses

MAXA, Karel January 2014 (has links)
The topic of this master's thesis is development of identity management solution for small and medium business. The thesis is divided into four major parts. The first part contains theoretical background as description of RBAC model or model with relationships between practically used objects (user identity, role, position, permission, account...). Analysis of functioning and needs of targeted organizations was carried out in the second part. The third part describes the design of the developed application. The fourth part discusses actual implementation of the application. The main outcome of the thesis is implemented application that can be deployed at thesis defined organizations. The application includes all the functionality required in the first phase of the project.
119

Romští žáci a výuka občanské výchovy na základních praktických školách / Roma pupils and the civic education on practical primary schools

STROPNICKÁ, Kristýna January 2016 (has links)
The diploma thesis deals the phenomenon of education of Roma children in the system of special elementary education. The aim of the thesis is to capture the specifics of this education focusing on the analysis of the civic education on primary practical schools in context of relationships to Roma pupils. The theoretical part is focused on the current situation of the Roma minority in the Czech republic. The work briefly describes the history of the Roma minority and the current situation of Roma people in the modern society. Most attention is paid to the Czech primary educational system, especially teaching Roma pupils on practical primary schools. The work briefly deals with the current changes in the educational system, so called inclusive education too. The practical part is focused on the methodology of the multicultural education themes, on the second degree of an elementary practical school in Vimperk.
120

The role of Gata3 in blood stem cell emergence

Zaidan, Nada Mousa O. January 2018 (has links)
The first definitive haematopoietic stem cells (HSCs) produced during embryonic development are generated from a specialised subset of endothelial cells known as haemogenic endothelium. Recently, it was reported that Gata3 plays a dual role in the development of sympathetic nervous system and haematopoietic system. In fact, Gata3 has proven to be crucial for the production of HSCs through regulation of catecholamine production from the co-developing sympathetic nervous system. Also, it was recently shown that Gata3 is expressed in the haemogenic endothelium and haematopoietic progenitor cells. Here, I will specifically examine the role of Gata3 in the production of HSCs; if it is expressed and plays a role in the precursors from which HSCs arise. Using a Gata3-GFP reporter mouse line, we found that Gata3 is expressed in various cell types in the HSCs microenvironment, including mesenchymal cells, endothelial cells, haematopoietic cells and sympathetic nervous system, and this expression was stage dependant. In the endothelial cells, we have found that the haemogenic endothelium activity is enriched in Gata3 expressing cells. Within the haematopoietic cells, we have found that Gata3 marks a specific stage along the developmental pathway towards the generation of definitive haematopoietic stem cells, and that Gata3 expressing haematopoietic cells are enriched for the most immature and stem cell like progenitors. Moreover, Gata3 will be specifically knocked out in haemogenic endothelial cells to determine whether it plays an essential role in the production of HSCs from the endothelium using the Vec-Cre system. We found that Gata3 within the haemogenic endothelium plays a major role in haematopoietic progenitors formation, and possibly haematopoietic stem cell formation. Finally, we used molecular assay (RNA seq) to identify the role of Gata3 in the haematopoietic stem cell microenvironment and found that Gata3 plays a major role in the development and differentiation of various cells and systems, and implicated Gata3 as cell cycle regulator. In summary, we found that Gata3 expressing cells is enriched for haemogenic endothelium, crucial for the haematopoietic progenitors formation, plays and important role in endothelial to haematopoietic transition, and plays a key developmental role in both haematopoietic stem cell and its microenvironment.

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