This dissertation examines the dominant discourse of welfare dependency and its implications for lone mothers in Ontario, Canada. This hegemonic discourse has been instrumental in positioning lone mothers as deviant, pathologically flawed and ineffective citizens. Using a repeated survival analysis, I examine the spells of participants identifying the significant variables influencing social assistance exit rates. Social constructionism and critical feminism are the theoretical lenses underpinning the analysis. The quantitative study examines the current composition of the Ontario Works caseload, interrogates the legitimacy of the welfare dependency supposition, debunks numerous social constructions surrounding welfare receipt and highlights the barriers impeding participants. The study culminates with a new understanding to counter the welfare dependency paradigm, recognizing the overlooked provisioning work of women in the neoliberal post welfare state.

In the last decade, the world has witnessed rapid increasing applications of wireless networks. However, with the fixed spectrum allocation policy that has been used since the beginning of the spectrum regulation to assign different spectrum bands to different wireless applications, it has been observed that most of the allocated spectrum bands are underutilized. Therefore, if these bands can be opportunistically used by new emerging wireless networks, the spectrum scarcity can be resolved. Cognitive Radio (CR) is a revolutionary and promising technology that can identify and then exploit the spectrum opportunities. In Cognitive Radio Networks (CRNs), the spectrum can be utilized by two kinds of users: Primary Users (PUs) having exclusive licenses to use certain spectrum bands for specific wireless applications, and Secondary Users (SUs) having no spectrum licenses but seeking for any spectrum opportunities. The SUs can make use of the licensed unused spectrum if they do not make any harmful interference to the PUs. However, the variation of the spectrum availability over the time and locations, due to the coexistence with the PUs, and the spread of the spectrum opportunities over wide spectrum bands create a unique trait of the CRNs. This key trait poses great challenges in different aspects of the radio resource management in CRNs such as the spectrum sensing, spectrum access, admission control, channel allocation, Quality-of-Service (QoS) provisioning, etc. In this thesis, we study the resource management of both single-hop and multi-hop CRNs. Since most of the new challenges in CRNs can be tackled by designing an efficient Medium Access Control (MAC) framework, where the solutions of these challenges can be integrated for efficient resource management, we firstly propose a novel MAC framework that integrates a kind of cooperative spectrum sensing method at the physical layer into a cooperative MAC protocol considering the requirements of both the SUs and PUs. For spectrum identification, a computationally simple but efficient sensing algorithm is developed, based on an innovative deterministic sensing policy, to assist each sensing user for identifying the optimum number of channels to sense and the optimum sensing duration. We then develop an admission control scheme and channel allocation policy that can be integrated in the proposed MAC framework to regulate the number of sensing users and number of access users; therefore, the spectrum identification and exploitation can be efficiently balanced. Moreover, we propose a QoS-based spectrum allocation framework that jointly considers the QoS provisioning for heterogeneous secondary Real-Time (RT) and Non-Real Time (NRT) users with the spectrum sensing, spectrum access decision, and call admission control. We analyze the proposed QoS-based spectrum allocation framework and find the optimum numbers of the RT and NRT users that the network can support. Finally, we introduce an innovative user clustering scheme to efficiently manage the spectrum identification and exploitation in multi-hop ad hoc CRNs. We group the SUs into clusters based on their geographical locations and occurring times and use spread spectrum techniques to facilitate using one frequency for the Common Control Channels (CCCs) of the whole secondary network and to reduce the co-channel interference between adjacent clusters by assigning different spreading codes for different clusters. The research results presented in this thesis contribute to realize the concept of the CRNs by developing a practical MAC framework, spectrum sensing, spectrum allocation, user admission control, and QoS provisioning for efficient resource management in these promising networks.

In the last decade, the world has witnessed rapid increasing applications of wireless networks. However, with the fixed spectrum allocation policy that has been used since the beginning of the spectrum regulation to assign different spectrum bands to different wireless applications, it has been observed that most of the allocated spectrum bands are underutilized. Therefore, if these bands can be opportunistically used by new emerging wireless networks, the spectrum scarcity can be resolved. Cognitive Radio (CR) is a revolutionary and promising technology that can identify and then exploit the spectrum opportunities. In Cognitive Radio Networks (CRNs), the spectrum can be utilized by two kinds of users: Primary Users (PUs) having exclusive licenses to use certain spectrum bands for specific wireless applications, and Secondary Users (SUs) having no spectrum licenses but seeking for any spectrum opportunities. The SUs can make use of the licensed unused spectrum if they do not make any harmful interference to the PUs. However, the variation of the spectrum availability over the time and locations, due to the coexistence with the PUs, and the spread of the spectrum opportunities over wide spectrum bands create a unique trait of the CRNs. This key trait poses great challenges in different aspects of the radio resource management in CRNs such as the spectrum sensing, spectrum access, admission control, channel allocation, Quality-of-Service (QoS) provisioning, etc. In this thesis, we study the resource management of both single-hop and multi-hop CRNs. Since most of the new challenges in CRNs can be tackled by designing an efficient Medium Access Control (MAC) framework, where the solutions of these challenges can be integrated for efficient resource management, we firstly propose a novel MAC framework that integrates a kind of cooperative spectrum sensing method at the physical layer into a cooperative MAC protocol considering the requirements of both the SUs and PUs. For spectrum identification, a computationally simple but efficient sensing algorithm is developed, based on an innovative deterministic sensing policy, to assist each sensing user for identifying the optimum number of channels to sense and the optimum sensing duration. We then develop an admission control scheme and channel allocation policy that can be integrated in the proposed MAC framework to regulate the number of sensing users and number of access users; therefore, the spectrum identification and exploitation can be efficiently balanced. Moreover, we propose a QoS-based spectrum allocation framework that jointly considers the QoS provisioning for heterogeneous secondary Real-Time (RT) and Non-Real Time (NRT) users with the spectrum sensing, spectrum access decision, and call admission control. We analyze the proposed QoS-based spectrum allocation framework and find the optimum numbers of the RT and NRT users that the network can support. Finally, we introduce an innovative user clustering scheme to efficiently manage the spectrum identification and exploitation in multi-hop ad hoc CRNs. We group the SUs into clusters based on their geographical locations and occurring times and use spread spectrum techniques to facilitate using one frequency for the Common Control Channels (CCCs) of the whole secondary network and to reduce the co-channel interference between adjacent clusters by assigning different spreading codes for different clusters. The research results presented in this thesis contribute to realize the concept of the CRNs by developing a practical MAC framework, spectrum sensing, spectrum allocation, user admission control, and QoS provisioning for efficient resource management in these promising networks.

L'intensification de la concurrence et les exigences des clients pour des services toujours plus innovants et fiables conduisent l'opérateur à accélérer le renouvellement de son portefeuille de services et à vouloir devancer ses concurrents dans leur mise sur le marché. Mais dans le nouveau contexte NGN/NGS où l'utilisateur est nomade, change de terminal, change d'environnement et désire une continuité de service en tout lieu et selon ses préférences, la fourniture de services depuis la stratégie jusqu'à l'exploitation devient de plus en plus complexe et longue à maîtriser. Ainsi, avoir une gestion dynamique qui permet d'améliorer le TTM et le ROI devient un challenge pour les opérateurs. Dans cette thèse, nous nous intéressons à la résolution de problèmes de gestion du cycle de vie des services depuis le Déploiement jusqu'au Delivery dans un environnement ubiquitaire et mobile. Pour ce faire, dans un premier temps, nous commençons par analyser les travaux existants en termes de gestion du cycle de vie des services, puis nous identifions plus précisément les besoins du nouveau contexte NGN/NGS du point de vue de l'utilisateur et de l'opérateur. Les verrous à lever concernent les différentes phases du cycle de vie des services. Comment les repenser afin d'avoir une continuité de service et un maintien de la QoS dans ce contexte de mobilité et d'ubiquité. Nos contributions sont au nombre de quatre et concerne le Déploiement, le Provisioning, le Delivery et l'Assurance des services. Deux champs d'application sont directement impactés par nos propositions et permettent de valoriser nos travaux. Le premier se déduit de la gestion de la mobilité de la session de l'utilisateur par la QoS. Le deuxième est les standards télécom et plus particulièrement les processus business.

Made available in DSpace on 2016-12-12T20:22:51Z (GMT). No. of bitstreams: 1 Ricardo Pfiitscher.pdf: 2243500 bytes, checksum: 4b9ddaa4c55d3439be3a57cc0217a41d (MD5) Previous issue date: 2014-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Cloud computing has recently brought about a small revolution in information technology. In this paradigm, cloud providers assume the burden of acquiring, operating, and managing computing infrastructures, which are then rented to cloud customers. One of the cloud service models is infrastructure-as-a-service (IaaS), where providers offer processing, storage and communication capacity as resources, normally associated to virtual machine instances. Even if IaaS customers are able to adjust resource allocation to their needs a key cloud feature , sizing resources remains a challenge due to a lack of means to accurately identify how much capacity is needed to satisfy application demands. Many users end up underprovisioning, hurting application performance, or overprovisioning, paying for resources that are not really necessary. Our work introduces a diagnosis model that uses monitoring to enable a cloud customer to determine if the resources available to his virtual machines are correctly provisioned, or are under-/overprovisioned. We evaluated processor, memory and network resources, which can be easily provisioned in current virtualization environments. Experimental results with the Xen platform demonstrate the effectiveness of the proposed approach. / A computação em nuvem trouxe recentemente uma pequena revolução na tecnologia da informação. Neste paradigma, provedores de nuvem assumem o ônus de adquirir, operar e gerenciar infraestruturas computacionais, que são então locadas a clientes de nuvem. Um dos modelos de serviço de nuvens é infraestrutura como serviço (infrastructure-asa- service, IaaS), no qual provedores oferecem como recursos capacidades de processamento, armazenamento e comunicação, normalmente associadas a instâncias de máquinas virtuais. Ainda que clientes IaaS possam ajustar os recursos alocados de acordo com as suas necessidades uma característica chave das nuvens , o dimensionamento de recursos permanece um desafio, uma vez que faltam meios para identificar com precisão a capacidade necessária para satisfazer a demanda das aplicações. Muitos usuários incorrem no subprovisionamento, prejudicando o desempenho de suas aplicações, ou no superprovisionamento, pagando por recursos que não são realmente necessários. Este trabalho usa monitoração para prover um modelo de diagnóstico, permitindo que um cliente de nuvem determine se os recursos disponíveis para suas máquinas virtuais estão provisionados corretamente, ou se estão sub- ou superprovisionados. Foram avaliados os recursos de processador, memória e rede, que podem ser facilmente reservados nos ambientes de virtualização atuais. A eficácia da abordagem proposta é demonstrada por resultados experimentais em máquinas virtuais Linux na plataforma de virtualização Xen

[pt] Estudamos aproximações amostrais de problemas com restrições probabilísticas através da aproximação pela média amostral (SAA) e demonstramos as propriedades de convergência relacionadas. Utilizamos SAA para obter bons candidatos à solução e cotas estatísticas para o valor ótimo do problema original. Para ajustar corretamente parâmetros, aplicamos o método a dois problemas com restrições probabilísticas. O primeiro é um problema de seleção de portfolio linear com retornos seguindo uma distribuição lognormal multivariada. O segundo é uma versão com restrições probabilísticas conjuntas de um problema da mistura simplificado. Concluímos com uma aplicação mais exigente ao problema de se determinar a provisão mínima que um agente econômico deve ter de forma a satisfazer uma série de obrigações futuras com probabilidade suficientemente alta. / [en] We study sample approximations of chance constrained problems through the sample average approximation (SAA) approach and prove the related convergence properties. We discuss how to use the SAA method to obtain good candidate solutions and bounds for the optimal value of the original problem. In order to tune the parameters of SAA, we apply the method to two chance constrained problems. The first is a linear portfolio selection problem with returns following a multivariate lognormal distribution. The second is a joint chance constrained version of a simple blending problem. We conclude with a more demanding application of SAA methodology to the determination of the minimum provision an economic agent must have in order to meet a series of future payment obligations with sufficiently high probability.

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During the last decade, many European banks have been troubled with low profitability, while the amount of non-performing loans (NPLs) has increased. This thesis investigates and analyses how the increasing amount of NPL affects banks profitability and the financial system. With econometric models using panel data we examined the relationship between NPL, banks profitability and the economic cycle (GDP-growth). This combined with qualitative economic theories provided a solid analysis of this relationship. We found strong evidence the NPL-ratio has a negative correlation with both the profitability of banks and the economic cycle. With these results in mind we think the NPLs need to be dealt with by the banks and authorities soon. In accordance with our result and analysis we came up with recommendations for the banks and authorities to deal with the issue. We recognize they need to improve the secondary markets for non-performing loans, lifting the loans from their balance sheets, increase the use of Asset Management Companies and improve the NPL-management within banks.

Today, the increasing number of applications based on the Internet of Things, as well as advances in wireless communication, information and communication technology, and mobile cloud computing have allowed users to access a wide range of resources while mobile. Vehicular clouds are considered key elements for today’s intelligent transportation systems. They are outfitted with equipment to enable applications and services for vehicle drivers, surrounding vehicles, pedestrians and third parties. As vehicular cloud computing has become more popular, due to its ability to improve driver and vehicle safety and provide provisioning services and applications, researchers and industry have growing interest in the design and development of vehicular networks for emerging applications. Though vehicle drivers can now access a variety of on-demand resources en route via vehicular network service providers, the development of vehicular cloud provisioning services has many challenges. In this dissertation, we examine the most critical provisioning service challenges drivers face, including, cost, privacy and latency. To this point, very little research has addressed these issues from the driver perspective. Privacy and service latency are certainly emerging challenges for drivers, as are service costs since this is a relatively new financial concept. Motivated by the Quality of Experience paradigm and the concept of the Trusted Third Party, we identify and investigate these challenges and examine the limitations and requirements of a vehicular environment. We found no research that addressed these challenges simultaneously, or investigated their effect on one another. We have developed a Quality of Experience framework that provides scalability and reduces congestion overhead for users. Furthermore, we propose two theory-based frameworks to manage on-demand service provision in vehicular clouds: Auction-driven Multi-objective Provisioning and a Multiagent/Multiobjective Interaction Game System. We present different approaches to these, and show through analytical and simulation results that our potential schemes help drivers minimize costs and latency, and maximize privacy.

Studien undersöker i vilken mån man kan anpassa drönares funktion till leveranser av varor till fartyg i form av intervjustudier. Arbetet berör den ekonomisk vinning jämfört med de provianteringsfartyg som annars genomför denna transport samt de aspekter som handlar om drönaroperatörens inverkan på denna typ av tjänst. Undersökningen resulterade i att drönaren kan användas som komplement och att tekniken som finns på marknaden är tillräcklig för att på ett säkert sätt kunna genomföra leveranser till fartyg med drönare som hjälpmedel. Vidare visade studien att enligt de intervjuade drönaroperatörerna är det fortsatt oklart i vilken utsträckning som drönaren kommer kunna tillämpas då få drönare finns som är skräddarsydda för detta specifika ändamål men att det ses fortsatt positivt på implementeringen utav drönare som verktyg till sjöss. / The purpose of this study aims to investigate the extent to which the function of drones can be adapted to deliveries of goods to vessels. This study was conducted in the form of interview studies. The study concerns the economic gain of supply deliveries with drones compared to the provisioning vessels, that otherwise carry out this payload as well as the aspects that deal with the drone operator´s impact on this type of service. The study concluded that the drone can be used as a complement and that the technology available on the market is sufficient to be able to safely carry out these deliveries to vessels using drones as aids. Furthermore, the study showed that according to the interviewed drone operators, it is still unclear to what extent the drone will be applied as there are few drones that are tailored for this specific purpose, but that the implementation of drones as a tool at sea is still viewed positively.