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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.
261

Diseño de aplicaciones de tiempo real para plataformas abiertas

Barros Bastante, Laura 02 October 2012 (has links)
Se propone una metodología de desarrollo de aplicaciones de tiempo real estricto que van a ser ejecutadas en plataformas distribuidas abiertas. En esta metodología, el diseñador de la aplicación no conoce la carga de trabajo de la plataforma que será ejecutada concurrentemente junto con la aplicación que diseña. La metodología se basa en el paradigma de reserva de recursos, y utiliza como base el concepto de plataforma virtual, tanto para describir el uso de los recursos que una aplicación requiere, como para ejecutar la aplicación satisfaciendo sus requisitos temporales. La plataforma virtual es utilizada en el proceso de negociación con el servicio de reserva de recursos de la plataforma física, con objeto de obtener una configuración de la aplicación que haga compatible su ejecución con la carga de trabajo que ya se está ejecutando en dicha plataforma. La metodología aborda todas las fases del desarrollo de una aplicación: describe la información que debe asociarse al código de la aplicación para poder ser configurado, así como el proceso que permite analizar independientemente su planificabilidad en base a la plataforma virtual; especifica el proceso de despliegue de la aplicación y define la información que se utiliza para negociar su ejecución con el servicio de reserva de recursos de la plataforma física y para generar los datos de configuración que deben ser asignados al código cuando se ejecute. Todos estos procesos son dirigidos por modelos, por lo que la tesis aborda la definición de las transformaciones de modelos requeridas, así como la formulación de los metamodelos formales utilizados en ellas. Por otro lado, aunque la tecnología es independiente de la plataforma de ejecución, se especifica la funcionalidad que debe ofrecer el servicio de reserva de recursos presente en la misma para dar soporte a la metodología propuesta, y se analiza su compatibilidad con algunas implementaciones actualmente disponibles / This thesis proposes a methodology for the development of hard real-time applications that will be executed in open distributed platforms. When this methodology is applied, the application designer does not know the workload of the platform that will execute concurrently with the designed application. The methodology is based on the resource reservation paradigm, and relies on the concept of virtual platform, both to describe the resources usage required by an application to execute, and to run the application guaranteeing the fulfillment of the specified timing requirements. The virtual platform is also used on the negotiation process with the resource reservation service of the physical platform in order to obtain a configuration of the application that supports its execution together with the current workload running on that platform. The methodology deals with all the phases of the application design: it describes the information that must be associated to the application code in order to obtain a proper configuration, as well as the process that allows an independent schedulability analysis of the application based on its virtual platform; it specifies the application deployment process and defines the information that is used to negotiate the execution of the application with the resource reservation service of the physical platform, and to generate the configuration data that must be assigned to the code when it is executed. The methodology follows a model-driven perspective, so the thesis addresses the required models transformations, as well as the formulation of the metamodels used in them. Moreover, although the technology is independent from the execution platform, the functionality that must be provided by the resource reservation service to support the proposed technology is specified and its compatibility with other implementations is analyzed.
262

New signal processing approaches to peak-to-average power ratio reduction in multicarrier systems

Bae, Ki-taek 06 December 2010 (has links)
Multi-carrier systems based on orthogonal frequency division multiplexing (OFDM) are efficient technologies for the implementation of broadband wireless communication systems. OFDM is widely used and has been adopted for current mobile broadband wireless communication systems such as IEEE 802.a/g wireless LANs, WiMAX, 3GPP LTE, and DVB-T/H digital video broadcasting systems. Despite their many advantages, however, OFDM-based systems suffer from potentially high peak-to-average power ratio (PAR). Since communication systems typically include nonlinear devices such as RF power amplifiers (PA) and digital-to-analog converters (DAC), high PAR results in increased symbol error rates and spectral radiation. To mitigate these nonlinear effects and to avoid nonlinear saturation effects of the PA, the operating point of a signal with high peak power must be backed off into the linear region of the PA. This so-called output backoff (OBO) results in a reduced power conversion efficiency which limits the battery life for mobile applications, reduces the coverage range, and increases both the cost of the PA and power consumption in the cellular base station. With the increasing demand for high energy efficiency, low power consumption, and greenhouse gas emission reduction, PAR reduction is a key technique in the design of practical OFDM systems. Motivated by the PAR reduction problem associated with multi-carrier systems, such as OFDM, this research explores the state of the art of PAR reduction techniques and develops new signal processing techniques that can achieve a minimum PAR for given system parameters and that are compatible with the appropriate standards. The following are the three principal contributions of this dissertation research. First, we present and derive the semi-analytical results for the output of asymptotic iterative clipping and filtering. This work provides expressions and analytical techniques for estimating the attenuation factor, error vector magnitude, and bit-error-rate (BER), using a noise enhancement factor that is obtained by simulation. With these semi-analytical results, we obtain a relationship between the BER and the target clipping level for asymptotic iterative clipping and filtering. These results serve as a performance benchmark for designing PAR reduction techniques using iterative clipping and filtering in OFDM systems. Second, we analyze the impact of the selected mapping (SLM) technique on BER performance of OFDM systems in an additive white Gaussian noise channel in the presence of nonlinearity. We first derive a closed-form expression for the envelope power distribution in an OFDM system with SLM. Then, using this derived envelope power distribution, we investigate the BER performance and the total degradation (TD) of OFDM systems with SLM under the existence of nonlinearity. As a result, we obtain the TD-minimizing peak backoff (PBO) and clipping ratio as functions of the number of candidate signals in SLM. Third, we propose an adaptive clipping control algorithm and pilotaided algorithm to address a fundamental issue associated with two lowcomplexity PAR reduction techniques, namely, tone reservation (TR) and active constellation extension (ACE). Specifically, we discovered that the existing low-complexity algorithms have a low clipping ratio problem in that they can not achieve the minimum PAR when the target clipping level is set below the initially unknown optimum value. Using our proposed algorithms, we overcome this problem and demonstrate that additional PAR reduction is obtained for any low value of the initial target clipping ratio. / text
263

Recovery in the residential school abuse aftermath : a new healing paradigm

Dionne, Dee, University of Lethbridge. Faculty of Health Sciences January 2008 (has links)
This qualitative study informs the literature by bringing two perspectives together: the trauma of residential school abuse and the transpersonal viewpoint of healing. A phenomenological hermeneutic approach explored lived experiences of residential school survivors and their families. Transpersonal psychology was introduced as the focus for a new healing paradigm. The research questions ask, “What has been the lived experience of the trauma of residential school abuse” and “How are traditional and non-traditional healing practices mutually applied in the recovery process by individuals who are impacted by the residential school experience”? Five First Nations co-researchers were interviewed, the data was analyzed, coded, and a thematic analysis was undertaken from which six themes emerged. The results of this study may go on to employ this new healing paradigm to help First Nations people gain spiritual wholeness. Finally, a description and summary of research findings, limitations and implications for counselling were discussed. / x, 193 leaves ; 29 cm. --
264

PEAK TO AVERAGE POWER RATIO ANALYSIS AND REDUCTION OF COGNITIVE RADIO SIGNALS

Hussain, Sajjad 21 October 2009 (has links) (PDF)
* La multiplication des standards de télécommunications fait apparaître la nécessité de disposer de terminaux multistandard et reconfigurables. Ces nouvelles fonctionnalités trouvent leurs réponses dans le domaine de la radio logicielle. De tels terminaux ne sont pas encore réalisables pour des raisons technologiques liées à la complexité nécessaire à leur réalisation (convertisseurs ultra rapides, processeurs reconfigurables, antennes et amplificateurs très large bande, ....). En se basant alors sur une véritable technologie radio logicielle, la radio intelligente va encore plus loin dans la prospective en dotant le terminal de capteurs qui lui permettront de s'adapter et de réagir vis à vis de son environnement. La radio devient alors décentralisée et flexible se détachant de la notion de standards et transmettant de façon opportuniste une communication dans une bande qui aura été détectée comme libre. Cette présentation s'inscrit dans le contexte présenté ci-dessus en se focalisant sur les conséquences de l'amplification de puissance d'un signal multistandard. En effet, l'amplication de puissance est un étage fondamental de tout système radio et certaines précautions doivent être prises avant d'amplifier un signal. En effet, les amplificateurs ont des caractéristiques non linéaires et de faibles rendements nécessitant un traitement du signal à amplifier afin de limiter d'une part les distorsions non linéaires et d'autre part la consommation des terminaux. Les signaux caractérisant les systèmes multistandard ayant des caractéristiques proches de celle d'un signal OFDM (connu pour les problèmes liés à l'amplification de puissance), ce travail apporte des réponses sur : * les niveaux de puissance d'un signal multistandard * les méthodes à développer pour en minimiser les fluctuations de puissance * les conséquences de l'accès opportuniste au spectre sur les fluctuations de puissance dans un contexte de radio intelligente
265

Gestion des ressources dans les réseaux cellulaires sans fil

Nadembéga, Apollinaire 12 1900 (has links)
L’émergence de nouvelles applications et de nouveaux services (tels que les applications multimédias, la voix-sur-IP, la télévision-sur-IP, la vidéo-sur-demande, etc.) et le besoin croissant de mobilité des utilisateurs entrainent une demande de bande passante de plus en plus croissante et une difficulté dans sa gestion dans les réseaux cellulaires sans fil (WCNs), causant une dégradation de la qualité de service. Ainsi, dans cette thèse, nous nous intéressons à la gestion des ressources, plus précisément à la bande passante, dans les WCNs. Dans une première partie de la thèse, nous nous concentrons sur la prédiction de la mobilité des utilisateurs des WCNs. Dans ce contexte, nous proposons un modèle de prédiction de la mobilité, relativement précis qui permet de prédire la destination finale ou intermédiaire et, par la suite, les chemins des utilisateurs mobiles vers leur destination prédite. Ce modèle se base sur : (a) les habitudes de l’utilisateur en terme de déplacements (filtrées selon le type de jour et le moment de la journée) ; (b) le déplacement courant de l’utilisateur ; (c) la connaissance de l’utilisateur ; (d) la direction vers une destination estimée ; et (e) la structure spatiale de la zone de déplacement. Les résultats de simulation montrent que ce modèle donne une précision largement meilleure aux approches existantes. Dans la deuxième partie de cette thèse, nous nous intéressons au contrôle d’admission et à la gestion de la bande passante dans les WCNs. En effet, nous proposons une approche de gestion de la bande passante comprenant : (1) une approche d’estimation du temps de transfert intercellulaire prenant en compte la densité de la zone de déplacement en terme d’utilisateurs, les caractéristiques de mobilité des utilisateurs et les feux tricolores ; (2) une approche d’estimation de la bande passante disponible à l’avance dans les cellules prenant en compte les exigences en bande passante et la durée de vie des sessions en cours ; et (3) une approche de réservation passive de bande passante dans les cellules qui seront visitées pour les sessions en cours et de contrôle d’admission des demandes de nouvelles sessions prenant en compte la mobilité des utilisateurs et le comportement des cellules. Les résultats de simulation indiquent que cette approche réduit largement les ruptures abruptes de sessions en cours, offre un taux de refus de nouvelles demandes de connexion acceptable et un taux élevé d’utilisation de la bande passante. Dans la troisième partie de la thèse, nous nous penchons sur la principale limite de la première et deuxième parties de la thèse, à savoir l’évolutivité (selon le nombre d’utilisateurs) et proposons une plateforme qui intègre des modèles de prédiction de mobilité avec des modèles de prédiction de la bande passante disponible. En effet, dans les deux parties précédentes de la thèse, les prédictions de la mobilité sont effectuées pour chaque utilisateur. Ainsi, pour rendre notre proposition de plateforme évolutive, nous proposons des modèles de prédiction de mobilité par groupe d’utilisateurs en nous basant sur : (a) les profils des utilisateurs (c’est-à-dire leur préférence en termes de caractéristiques de route) ; (b) l’état du trafic routier et le comportement des utilisateurs ; et (c) la structure spatiale de la zone de déplacement. Les résultats de simulation montrent que la plateforme proposée améliore la performance du réseau comparée aux plateformes existantes qui proposent des modèles de prédiction de la mobilité par groupe d’utilisateurs pour la réservation de bande passante. / The emergence of new applications and services (e.g., multimedia applications, voice over IP and IPTV) and the growing need for mobility of users cause more and more growth of bandwidth demand and a difficulty of its management in Wireless Cellular Networks (WCNs). In this thesis, we are interested in resources management, specifically the bandwidth, in WCNs. In the first part of the thesis, we study the user mobility prediction that is one of key to guarantee efficient management of available bandwidth. In this context, we propose a relatively accurate mobility prediction model that allows predicting final or intermediate destinations and subsequently mobility paths of mobile users to reach these predicted destinations. This model takes into account (a) user’s habits in terms of movements (filtered according to the type of day and the time of the day); (b) user's current movement; (c) user’s contextual knowledge; (d) direction from current location to estimated destination; and (e) spatial conceptual maps. Simulation results show that the proposed model provides good accuracy compared to existing models in the literature. In the second part of the thesis, we focus on call admission control and bandwidth management in WCNs. Indeed, we propose an efficient bandwidth utilization scheme that consists of three schemes: (1) handoff time estimation scheme that considers navigation zone density in term of users, users’ mobility characteristics and traffic light scheduling; (2) available bandwidth estimation scheme that estimates bandwidth available in the cells that considers required bandwidth and lifetime of ongoing sessions; and (3) passive bandwidth reservation scheme that passively reserves bandwidth in cells expected to be visited by ongoing sessions and call admission control scheme for new call requests that considers the behavior of an individual user and the behavior of cells. Simulation results show that the proposed scheme reduces considerably the handoff call dropping rate while maintaining acceptable new call blocking rate and provides high bandwidth utilization rate. In the third part of the thesis, we focus on the main limitation of the first and second part of the thesis which is the scalability (with the number of users) and propose a framework, together with schemes, that integrates mobility prediction models with bandwidth availability prediction models. Indeed, in the two first contributions of the thesis, mobility prediction schemes process individual user requests. Thus, to make the proposed framework scalable, we propose group-based mobility prediction schemes that predict mobility for a group of users (not only for a single user) based on users’ profiles (i.e., their preference in terms of road characteristics), state of road traffic and users behaviors on roads and spatial conceptual maps. Simulation results show that the proposed framework improves the network performance compared to existing schemes which propose aggregate mobility prediction bandwidth reservation models.
266

Squaring the circle game: a critical look at Canada’s 2008 apology to former students of Indian residential schools

Radmacher, Michael Boldt 27 August 2010 (has links)
On 11 June 2008 the Government of Canada delivered an official apology to former students of Indian residential schools for its participation in the schools’ creation and administration. The morally infused discourses of political apologies may at first seem to symbolize a progressive step towards a better and more egalitarian future. This thesis, however, will challenge and problematize such perspectives by presenting not only a critical analysis of the 2008 apology itself but also by contextualizing the apology’s narratives with the colonial framing strategies which have historically served to marginalize and dominate the Indigenous nations and peoples of Turtle Island. Through the critical exploration of the 2008 apology’s operability and political significance in Canada’s colonial context, this thesis intends to reveal both the message(s) that the apology got across to the Canadian general public and the forms of domination and political distraction that the apology’s seemingly moral and progressive narratives effectively belie.
267

實質選擇權與工作搜尋決策-以台灣失業者為例 / Real Options and Job Search Decisions-Evidence from the Unemployed in Taiwan

薛博升, Hsueh, Po Sheng Unknown Date (has links)
本文分成兩個部分探討失業者的工作搜尋決策,第一部分利用遞延選擇權模型模擬市場景氣、預期工作機會出現機率、不確定性等因素對失業者工作搜尋決策的影響。第二部份利用2006年至2010年主計處的「人力資源調查」及「人力運用調查」資料從事實證分析。本文從實證分析中驗證以下的模擬結果:一、市場上的工資波動率與失業者的保留工資有正向關係,與移轉到就業的機率有負向關係。二、失業者對工作機會出現機率的預期較高時,擁有較高的保留工資,移轉到就業的機率較低。另外,學習速度較快的失業者在搜尋工作的過程中會以較快的速度下降保留工資,移轉到就業的機率較高。三、失業者對於工作搜尋報酬的不確定程度較高時,擁有較低的保留工資,移轉到就業的機率較高。 / This thesis consists of two parts. The first part is devoted to applying a real option approach to simulate the impacts of market prospect, expected offer arrival rate, and uncertainty on job search decisions. The second part provides an empirical illustration to validate the simulation results by using unemployment data from the 2006-2010 Taiwan Manpower Utilization Survey. The main findings of this thesis can be summarized as follows: (i) The wage volatility is related positively with the reservation wage of the unemployed, but inversely with the transition probability into employment. (ii) If a rising offer arrival rate is expected, the unemployed increase reservation wages and thus decrease transition probabilities. Furthermore, higher learning speed acts to intensively lower the reservation wage. (iii) When the degree of payoff uncertainty is higher, the unemployed decrease reservation wages and thus increase transition probabilities.
268

A efetivação judicial do direito fundamental à saúde e o orçamento público / The judicial execution of the fundamental right to health and the public budget

José Luis Castro Rodriguez 29 August 2014 (has links)
O presente trabalho tem por objetivo estudar as principais questões relacionadas à efetivação pelo Poder Judiciário do direito social a saúde. Serão analisados na primeira parte do trabalho os direitos sociais fundamentais e o mínimo existencial, no qual se inclui o direito à saúde, abordando-se a importância dada pela Constituição Federal a tal direito e sua regulamentação infraconstitucional, com destaque para a organização do Estado e as fontes de recursos. Após se demonstrar a importância do direito à saúde como direito social fundamental, será estudada na segunda parte do trabalho a escassez de recursos para o atendimento de todas as necessidades da população, abordando-se o conceito de reserva do possível e a relevância das leis orçamentárias para o alcance as prioridades sociais. Por fim, será demonstrada a legitimidade e necessidade de ingerência do Poder Judiciário na concretização do direito à saúde, destacando-se as posições doutrinárias e decisões judiciais que buscam alcançar o equilíbrio entre o atendimento de tal direito fundamental, o reconhecimento da limitação de recursos e a valorização do orçamento público. / The present work aims to study the main issues related to the implementation by the judiciary of the social right to health. In the first part of the work, it will be analyzed the fundamental social rights and the existential minimum, which includes the right to health, addressing the importance given by the Federal Constitution to such law and its regulations infra, with emphasis on the Organization of the State and the sources of funds. After demonstrating the importance of the right to health as a fundamental social right, in the second part of the work it will be studied the scarcity of resources for the care of all the needs of the population, addressing the concept of reservation is possible and the relevance of budget laws to achieve social priorities. Finally, the legitimacy and necessity of interference of the judiciary in the realization of the right to health will be demonstrated, emphasizing doctrinal positions and judicial decisions that seek to achieve a balance between the availability of such a fundamental right, the recognition of the limitation of resources and the enhancement of the public budget.
269

A efetivação judicial do direito fundamental à saúde e o orçamento público / The judicial execution of the fundamental right to health and the public budget

José Luis Castro Rodriguez 29 August 2014 (has links)
O presente trabalho tem por objetivo estudar as principais questões relacionadas à efetivação pelo Poder Judiciário do direito social a saúde. Serão analisados na primeira parte do trabalho os direitos sociais fundamentais e o mínimo existencial, no qual se inclui o direito à saúde, abordando-se a importância dada pela Constituição Federal a tal direito e sua regulamentação infraconstitucional, com destaque para a organização do Estado e as fontes de recursos. Após se demonstrar a importância do direito à saúde como direito social fundamental, será estudada na segunda parte do trabalho a escassez de recursos para o atendimento de todas as necessidades da população, abordando-se o conceito de reserva do possível e a relevância das leis orçamentárias para o alcance as prioridades sociais. Por fim, será demonstrada a legitimidade e necessidade de ingerência do Poder Judiciário na concretização do direito à saúde, destacando-se as posições doutrinárias e decisões judiciais que buscam alcançar o equilíbrio entre o atendimento de tal direito fundamental, o reconhecimento da limitação de recursos e a valorização do orçamento público. / The present work aims to study the main issues related to the implementation by the judiciary of the social right to health. In the first part of the work, it will be analyzed the fundamental social rights and the existential minimum, which includes the right to health, addressing the importance given by the Federal Constitution to such law and its regulations infra, with emphasis on the Organization of the State and the sources of funds. After demonstrating the importance of the right to health as a fundamental social right, in the second part of the work it will be studied the scarcity of resources for the care of all the needs of the population, addressing the concept of reservation is possible and the relevance of budget laws to achieve social priorities. Finally, the legitimacy and necessity of interference of the judiciary in the realization of the right to health will be demonstrated, emphasizing doctrinal positions and judicial decisions that seek to achieve a balance between the availability of such a fundamental right, the recognition of the limitation of resources and the enhancement of the public budget.
270

Análise do direito público subjetivo ao ensino obrigatório e gratuito em face da teoria da reserva do possível

Dias, Dhenize Maria Franco 16 February 2011 (has links)
Made available in DSpace on 2016-03-15T19:33:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-16 / Fundo Mackenzie de Pesquisa / Among the fundamental rights we have the right to education, a constitutional right extended to all, pursuant to provisions of Article 205 of the Federal Constitution [of Brazil]. It ranks as one of the most significant among the social rights, being conceived of within the notion of second dimension rights. They are the result of the process of constitutionalization of human rights, seeking to bring assertion and effectiveness into the principle of human dignity. Such rights impose upon the Public Power the enforcement of the duty of positive performance, consisting of a mandate to do or facere on the part of the State. This work had the general scope of analyzing the possibility of the State to exempt itself from the constitutional must of delivering and guaranteeing basic education with grounds on allegation of the theory of reservation based on feasibility. Given the objectives of the research, the approach utilized was a qualitative one. Thus, the right to a basic, mandatory and free-ofcharge education was analyzed, as erected to the category of a public, subjective right pursuant to the terms of Article 208, Paragraph 1, of the Federal Constitution/88, which provides that "access to mandatory and free teaching is a public, subjective right", following recent modification brought in by Constitutional Amendment No. 59, dated November 11, 2009. It has been concluded that the State may not exempt itself from its constitutional duty as to delivering and guaranteeing basic education, a fundamental right of social nature belonging to the human person, as it resorts to clause of "reservation based on feasibility", even within a limited scale of choices over public policies and a universe bound by scarce financial resources and restrained by public budget. / Entre os direitos fundamentais, temos o direito à educação, direito constitucional deferido a todos, nos termos do art. 205 da Constituição Federal de 1988. Qualificase como um dos direitos sociais mais expressivos, subsumindo-se à noção dos direitos de segunda dimensão. Trata-se de resultado do processo de constitucionalização dos direitos humanos, com vistas à positivação e efetividade do princípio da dignidade humana. Referidos direitos impõem ao Poder Público a satisfação do dever de prestação positiva, consistente em um facere do Estado.Este trabalho teve como objetivo geral analisar a possibilidade de o Estado exonerar-se do dever constitucional de oferecer e garantir a educação básica com fundamento na alegação da teoria da reserva do possível. Tendo em vista os objetivos da pesquisa, utilizou-se a abordagem qualitativa. Assim, analisamos o direito ao ensino obrigatório e gratuito, erigido à categoria de direito público subjetivo, nos termos do artigo 208, parágrafo 1º., da CF/88, que dispõe que o acesso ao ensino obrigatório e gratuito é direito público subjetivo , após recente alteração feita pela Emenda Constitucional nº. 59, de 11 de novembro de 2009. Verificou-se que o Estado não pode se eximir de seu dever constitucional quanto ao oferecimento e à garantia do ensino obrigatório e gratuito, direito fundamental de natureza social da pessoa humana, ao invocar a cláusula da "reserva do possível", que consiste no fenômeno econômico da limitação de recursos financeiros pelo Estado, mesmo dentro de uma cartela limitada de escolhas por políticas públicas e de um universo de recursos financeiros escassos e limitados pelo orçamento público.

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