983 resultados para limited resource
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In the traditional paradigm, the large power plants supply the reactive power required at a transmission level and the capacitors and transformer tap changer were also used at a distribution level. However, in a near future will be necessary to schedule both active and reactive power at a distribution level, due to the high number of resources connected in distribution levels. This paper proposes a new multi-objective methodology to deal with the optimal resource scheduling considering the distributed generation, electric vehicles and capacitor banks for the joint active and reactive power scheduling. The proposed methodology considers the minimization of the cost (economic perspective) of all distributed resources, and the minimization of the voltage magnitude difference (technical perspective) in all buses. The Pareto front is determined and a fuzzy-based mechanism is applied to present the best compromise solution. The proposed methodology has been tested in the 33-bus distribution network. The case study shows the results of three different scenarios for the economic, technical, and multi-objective perspectives, and the results demonstrated the importance of incorporating the reactive scheduling in the distribution network using the multi-objective perspective to obtain the best compromise solution for the economic and technical perspectives.
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This article deals with a real-life waste collection routing problem. To efficiently plan waste collection, large municipalities may be partitioned into convenient sectors and only then can routing problems be solved in each sector. Three diverse situations are described, resulting in three different new models. In the first situation, there is a single point of waste disposal from where the vehicles depart and to where they return. The vehicle fleet comprises three types of collection vehicles. In the second, the garage does not match any of the points of disposal. The vehicle is unique and the points of disposal (landfills or transfer stations) may have limitations in terms of the number of visits per day. In the third situation, disposal points are multiple (they do not coincide with the garage), they are limited in the number of visits, and the fleet is composed of two types of vehicles. Computational results based not only on instances adapted from the literature but also on real cases are presented and analyzed. In particular, the results also show the effectiveness of combining sectorization and routing to solve waste collection problems.
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Cloud data centers have been progressively adopted in different scenarios, as reflected in the execution of heterogeneous applications with diverse workloads and diverse quality of service (QoS) requirements. Virtual machine (VM) technology eases resource management in physical servers and helps cloud providers achieve goals such as optimization of energy consumption. However, the performance of an application running inside a VM is not guaranteed due to the interference among co-hosted workloads sharing the same physical resources. Moreover, the different types of co-hosted applications with diverse QoS requirements as well as the dynamic behavior of the cloud makes efficient provisioning of resources even more difficult and a challenging problem in cloud data centers. In this paper, we address the problem of resource allocation within a data center that runs different types of application workloads, particularly CPU- and network-intensive applications. To address these challenges, we propose an interference- and power-aware management mechanism that combines a performance deviation estimator and a scheduling algorithm to guide the resource allocation in virtualized environments. We conduct simulations by injecting synthetic workloads whose characteristics follow the last version of the Google Cloud tracelogs. The results indicate that our performance-enforcing strategy is able to fulfill contracted SLAs of real-world environments while reducing energy costs by as much as 21%.
A real-time quantitative assay for hepatitis B DNA virus (HBV) developed to detect all HBV genotypes
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Hepatitis B virus (HBV) is a major cause of chronic liver disease worldwide. Besides genotype, quantitative analysis of HBV infection is extensively used for monitoring disease progression and treatment. Affordable viral load monitoring is desirable in resource-limited settings and it has been already shown to be useful in developing countries for other viruses such as Hepatitis C virus (HCV) and HIV. In this paper, we describe the validation of a real-time PCR assay for HBV DNA quantification with TaqMan chemistry and MGB probes. Primers and probes were designed using an alignment of sequences from all HBV genotypes in order to equally amplify all of them. The assay is internally controlled and was standardized with an international HBV panel. Its efficacy was evaluated comparing the results with two other methods: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) and another real-time PCR from a reference laboratory. Intra-assay and inter-assay reproducibilities were determined and the mean of CV values obtained were 0.12 and 0.09, respectively. The assay was validated with a broad dynamic range and is efficient for amplifying all HBV genotypes, providing a good option to quantify HBV DNA as a routine procedure, with a cheap and reliable protocol.
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BACKGROUND: Sporotrichosis is a subacute or chronic disease caused by a dimorphic fungus, Sporothrix schenckii. The first and most traditional treatment is potassium iodide in satured solution (SSKI) used by DE BEURMANN in 1907. For its effectiveness, it is still used for cutaneous sporotrichosis. OBJECTIVE: To evaluate the treatment of cutaneous sporotrichosis with SSKI in relation to clinical cure, side effects, length of treatment and reactivation. METHODS: We conducted a retrospective analysis of medical records over a 24-year period (1981-2005). Patients of all ages who were treated in the hospital´s division of dermatology were included in the study providing that they had a positive culture of S. schenckii. Satured solution of potassium iodide (3 to 6g per day) was the treatment prescribed. For children, half of the dose was prescribed. RESULTS: The lymphocutaneous disease was prevalent, the cure rate was 94.7%, side effects were described in 5.5% of the cases, mean length of treatment was 3.5 months and possible reactivation was observed in 11.1%. CONCLUSION: SSKI is an effective drug, with many side effects, but with low frequency. Resolution was for maximum six months of treatment. SSKI has been found to be a very effective drug in this retrospective study of culture-proven cases of cutaneous and lymphocutaneous sporotrichosis. It should be used as first drug of choice especially in resource-limited settings.
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O estudo que apresentamos tem como objetivos de investigação contribuir para o desenvolvimento global das crianças com Necessidades Educativas Especiais, nomeadamente, portadoras de Dislexia, designadamente em aulas onde são lecionados conteúdos de Ciências da Natureza e de Matemática, e conceber um recurso didático apoiado nas TIC que seja adequado à utilização em sala de aula por alunos com dislexia. Neste sentido, o estudo foi orientado pelas seguintes questões de investigação: A utilização do Scratch é adequada e exequível no trabalho quotidiano de alunos portadores de Dislexia? e Em que medida o Scratch pode contribuir para um melhor envolvimento dos alunos portadores de Dislexia na realização das tarefas propostas? O presente trabalho segue uma metodologia de carácter qualitativo, centrando-se no estudo de caso. Tentou-se dar uma resposta à reduzida utilização do software Scratch no ensino das Ciências da Natureza e Matemática como instrumentos viáveis para uma aprendizagem de sucesso em alunos portadores de Dislexia. Este estudo foi aplicado a três alunos do 4º ano, com este diagnóstico, de um agrupamento de escolas do concelho de Viseu. Para dar resposta às questões de investigação supracitadas foram implementadas e projetadas duas atividades no software Scratch para serem desenvolvidas em duas situações formativas contextualizadas. O subdomínio que se pretendeu trabalhar foi “A importância da água para os seres vivos” articulando com o conteúdo dos volumes. Os dados foram recolhidos através da análise dos Programas Educativos Individuais de cada um dos alunos participantes, das entrevistas às docentes de Educação Especial, de gravações áudio, fotografias, trabalhos dos alunos e os registos da professora investigadora. Os resultados obtidos permitiram caracterizar o modo como os alunos, portadores de dislexia, se envolveram com o Scratch na aquisição de conhecimento. Permitiram ainda demonstrar aos professores que é possível construir atividades nesta ferramenta envolvendo conteúdos curriculares interdisciplinares.
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This paper presents the CloudAnchor brokerage platform for the transaction of single provider as well as federated Infrastructure as a Service (IaaS) resources. The platform, which is a layered Multi-Agent System (MAS), provides multiple services, including (consumer or provider) business registration and deregistration, provider coalition creation and termination, provider lookup and invitation and negotiation services regarding brokerage, coalitions and resources. Providers, consumers and virtual providers, representing provider coalitions, are modelled by dedicated agents within the platform. The main goal of the platform is to negotiate and establish Service Level Agreements (SLA). In particular, the platform contemplates the establishment of brokerage SLA – bSLA – between the platform and each provider or consumer, coalition SLA – cSLA – between the members of a coalition of providers and resource SLA – rSLA – between a consumer and a provider. Federated resources are detained and negotiated by virtual providers on behalf of the corresponding coalitions of providers.
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação
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Tese apresentada como requisito parcial para obtenção do grau de Doutor em Gestão de Informação
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In the latest years the wind energy sector experienced an exponential growth all over the world. What started as a deployment of onshore projects, soon moved to offshore and, more recently to the urban environment within the context of smart cities and renewable micro-generation. However, urban wind projects using micro turbines do not have enough profit margins to enable the setup of comprehensive and expensive measurement campaigns, a standard procedure for the deployment of large wind parks. To respond to the wind assessment needs of the future smart cities a new and simple methodology for urban wind resource assessment was developed. This methodology is based on the construction of a surface involving a built area in order to estimate the wind potential by treating it as very complex orography. This is a straightforward methodology that allows estimating the sustainable urban wind potential, being suitable to map the urban wind resource in large areas. The methodology was applied to a case study and the results enabled the wind potential assessment of a large urban area being consistent with experimental data obtained in the case study area, with maximum deviations of the order of 10% (mean wind speed) and 20% (power density).
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INTRODUCTION: Tuberculosis (TB) control is linked to the availability of qualified methods for microbiological diagnostics; however, microscopy with limited sensitivity is the only method available in many locations. The objective of this study was to evaluate the introduction of culture, drug susceptibility testing (DST), and genotyping in the routine of a Municipal Program of Tuberculosis Control. METHODS: Direct microscopy of sputum and culture in Ogawa-Kudoh were performed on 1,636 samples from 787 patients. DST of positive cultures was performed by resazurin microtiter assay and genotyping by mycobacterial interspersed repetitive units-variable number tandem repeat. RESULTS: A total 91 patients with TB were identified. The culture increased case detection by 32% compared with the microscopy; acquired resistance was 3.3% and the genotyping showed high genetic diversity. CONCLUSIONS: Ogawa-Kudoh contributed significantly to the increase in case detection and is suitable for implementation in poor-resource locations. The acquired resistance rate was lower than that reported in a recent Brazilian survey. The high genetic diversity is possibly related to the high TB prevalence in the population, as well as to early detection and suitable treatment of patients. The interaction between research and health care is important for reorienting the practice, transferring technology, and improving TB control.
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RESUMO: O Ministério da Saúde do Governo do Ruanda identifica a saúde mental como uma área de prioridade estratégica para a intervenção em resposta à alta carga dos transtornos mentais no Ruanda. Ao longo dos últimos 20 anos após o genocídio, o sector público reconstruiu sua Resposta Nacional de Saúde Mental com base no acesso equitativo aos cuidados, através do desenvolvimento de uma Política Nacional de Saúde Mental e novas estruturas de saúde mental. A política de Saúde Mental do Ruanda, revista em 2010, prima pela descentralização e integração dos serviços de saúde mental em todas as estruturas nacionais do sistema de saúde e ao nível da comunidade. O presente estudo de caso tem como objetivo avaliar a situação do sistema de saúde mental de um distrito típico de uma área rural no Ruanda, e sugerir melhorias, incluindo algumas estratégias para monitoras as mudanças. Os resultados do estudo permitirão ao Ruanda reforçar a sua capacidade para implementar o Plano Nacional de Saúde Mental ao nível dos distritos. O relatório também será útil para monitorar o progresso da implementação de serviços de saúde mental nos distritos, incluindo a prestação de serviços de base comunitária e a participação dos usuários, suas famílias e outros interessados na promoção, prevenção, assistência e reabilitação em saúde mental. Este estudo também procurou avaliar o progresso da implementação dos cuidados de saúde mental a nível descentralizado, com vista a compreender as implicações em termos de recursos desses processos. Foi realizada uma análise situacional num local do distrito, baseado em entrevistas com as principais partes interessadas responsáveis, usando o Instrumento de Avaliação de Sistemas de Saúde Mental da Organização Mundial da Saúde (WHO-AIMS). Os resultados sugerem que os recursos humanos para a saúde mental e serviços de base comunitária de saúde mental no distrito continuam a ser extremamente limitados. Os profissionais de saúde mental são adicionalmente limitados na sua capacidade para oferecer intervenções de emergência a pacientes psiquiátricos e garantir a continuidade do tratamento farmacológico a pacientes com condições crônicas. Para planejar efetivamente, de acordo com as necessidades da comunidade, sugerimos que o sistema de saúde mental deve envolver também os representantes das famílias e dos usuários no processo de planificação de modo a melhorar a sua contribuição no processo de implementação das atividades de saúde mental. Este estudo de caso do Distrito de Bugesera oferece a primeira análise de nível distrital dos serviços de saúde mental no Ruanda, e pode servir como uma mais-valia para a melhoria do sistema de saúde mental, incluindo a advocacia para a melhoria da qualidade dos cuidados de saúde mental a este nível, aumentando o financiamento para a implementação de serviços clínicos de saúde mental e os recursos humanos disponíveis para a prestação de cuidados de saúde mental, principalmente a nível dos cuidados primários.--------------------- ABSTRACT: To deal with the high burden of mental health disorders resulting from consequences of the 1994 genocide against Tutsis, the Rwanda Ministry of Health (MoH) considers mental health as a priority intervention. For the last 20 years, Ministry of Health focused on rebuilding a national and equity-oriented mental health program responding to the population needs in mental health. Mental health services are now decentralized and integrated in the national health system, from the community level up to the referral level. This study assessed the situation of mental health services in one rural district in Rwanda. It was aimed at assessing the progress of implementation of mental health care at the decentralized level, focusing on resource implications and processes. This study is based on interviews conducted with key stakeholders, using the World Health Organization's Assessment Instrument for Mental Health Systems (WHO-AIMS). Findings show that human resources for mental health care and community-based mental health services of the assessed district remain extremely limited. Mental health professionals face limitation regarding the ability to provide emergency management of psychiatric patients and to ensure continuity of psychopharmacological treatment of patients with chronic conditions. To improve the implementation process of mental health interventions and activities, a planning process based on community needs and the involvement of representatives of families and users in planning process should be considered. The Bugesera case study on the situation of mental health services can serve as a baseline for improvement of the mental health program in Rwanda, in terms of quality care services, infrastructure and equipment, human and financial resources.
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The way in which electricity networks operate is going through a period of significant change. Renewable generation technologies are having a growing presence and increasing penetrations of generation that are being connected at distribution level. Unfortunately, a renewable energy source is most of the time intermittent and needs to be forecasted. Current trends in Smart grids foresee the accommodation of a variety of distributed generation sources including intermittent renewable sources. It is also expected that smart grids will include demand management resources, widespread communications and control technologies required to use demand response are needed to help the maintenance in supply-demand balance in electricity systems. Consequently, smart household appliances with controllable loads will be likely a common presence in our homes. Thus, new control techniques are requested to manage the loads and achieve all the potential energy present in intermittent energy sources. This thesis is focused on the development of a demand side management control method in a distributed network, aiming the creation of greater flexibility in demand and better ease the integration of renewable technologies. In particular, this work presents a novel multi-agent model-based predictive control method to manage distributed energy systems from the demand side, in presence of limited energy sources with fluctuating output and with energy storage in house-hold or car batteries. Specifically, here is presented a solution for thermal comfort which manages a limited shared energy resource via a demand side management perspective, using an integrated approach which also involves a power price auction and an appliance loads allocation scheme. The control is applied individually to a set of Thermal Control Areas, demand units, where the objective is to minimize the energy usage and not exceed the limited and shared energy resource, while simultaneously indoor temperatures are maintained within a comfort frame. Thermal Control Areas are overall thermodynamically connected in the distributed environment and also coupled by energy related constraints. The energy split is performed based on a fixed sequential order established from a previous completed auction wherein the bids are made by each Thermal Control Area, acting as demand side management agents, based on the daily energy price. The developed solutions are explained with algorithms and are applied to different scenarios, being the results explanatory of the benefits of the proposed approaches.