854 resultados para Cloud-computing
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Human activity is very dynamic and subtle, and most physical environments are also highly dynamic and support a vast range of social practices that do not map directly into any immediate ubiquitous computing functionally. Identifying what is valuable to people is very hard and obviously leads to great uncertainty regarding the type of support needed and the type of resources needed to create such support. We have addressed the issues of system development through the adoption of a Crowdsourced software development model [13]. We have designed and developed Anywhere places, an open and flexible system support infrastructure for Ubiquitous Computing that is based on a balanced combination between global services and applications and situated devices. Evaluation, however, is still an open problem. The characteristics of ubiquitous computing environments make their evaluation very complex: there are no globally accepted metrics and it is very difficult to evaluate large-scale and long-term environments in real contexts. In this paper, we describe a first proposal of an hybrid 3D simulated prototype of Anywhere places that combines simulated and real components to generate a mixed reality which can be used to assess the envisaged ubiquitous computing environments [17].
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Kidney renal failure means that one’s kidney have unexpectedly stopped functioning, i.e., once chronic disease is exposed, the presence or degree of kidney dysfunction and its progression must be assessed, and the underlying syndrome has to be diagnosed. Although the patient’s history and physical examination may denote good practice, some key information has to be obtained from valuation of the glomerular filtration rate, and the analysis of serum biomarkers. Indeed, chronic kidney sickness depicts anomalous kidney function and/or its makeup, i.e., there is evidence that treatment may avoid or delay its progression, either by reducing and prevent the development of some associated complications, namely hypertension, obesity, diabetes mellitus, and cardiovascular complications. Acute kidney injury appears abruptly, with a rapid deterioration of the renal function, but is often reversible if it is recognized early and treated promptly. In both situations, i.e., acute kidney injury and chronic kidney disease, an early intervention can significantly improve the prognosis.The assessment of these pathologies is therefore mandatory, although it is hard to do it with traditional methodologies and existing tools for problem solving. Hence, in this work, we will focus on the development of a hybrid decision support system, in terms of its knowledge representation and reasoning procedures based on Logic Programming, that will allow one to consider incomplete, unknown, and even contradictory information, complemented with an approach to computing centered on Artificial Neural Networks, in order to weigh the Degree-of-Confidence that one has on such a happening. The present study involved 558 patients with an age average of 51.7 years and the chronic kidney disease was observed in 175 cases. The dataset comprise twenty four variables, grouped into five main categories. The proposed model showed a good performance in the diagnosis of chronic kidney disease, since the sensitivity and the specificity exhibited values range between 93.1 and 94.9 and 91.9–94.2 %, respectively.
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The development of ubiquitous computing (ubicomp) environments raises several challenges in terms of their evaluation. Ubicomp virtual reality prototyping tools enable users to experience the system to be developed and are of great help to face those challenges, as they support developers in assessing the consequences of a design decision in the early phases of development. Given the situated nature of ubicomp environments, a particular issue to consider is the level of realism provided by the prototypes. This work presents a case study where two ubicomp prototypes, featuring different levels of immersion (desktop-based versus CAVE-based), were developed and compared. The goal was to determine the cost/benefits relation of both solutions, which provided better user experience results, and whether or not simpler solutions provide the same user experience results as more elaborate one.
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Uno de los temas centrales del proyecto concierne la naturaleza de la ciencia de la computación. La reciente aparición de esta disciplina sumada a su origen híbrido como ciencia formal y disciplina tecnológica hace que su caracterización aún no esté completa y menos aún acordada entre los científicos del área. En el trabajo Three paradigms of Computer Science de A. Eden, se presentan tres posiciones admitidamente exageradas acerca de como entender tanto el objeto de estudio (ontología) como los métodos de trabajo (metodología) y la estructura de la teoría y las justificaciones del conocimiento informático (epistemología): La llamada racionalista, la cual se basa en la idea de que los programas son fórmulas lógicas y que la forma de trabajo es deductiva, la tecnocrática que presenta a la ciencia computacional como una disciplina ingenieril y la ahi llamada científica, la cual asimilaría a la computación a las ciencias empíricas. Algunos de los problemas de ciencia de la computación están relacionados con cuestiones de filosofía de la matemática, en particular la relación entre las entidades abstractas y el mundo. Sin embargo, el carácter prescriptivo de los axiomas y teoremas de las teorías de la programación puede permitir interpretaciones alternativas y cuestionaría fuertemente la posibilidad de pensar a la ciencia de la computación como una ciencia empírica, al menos en el sentido tradicional. Por otro lado, es posible que el tipo de análisis aplicado a las ciencias de la computación propuesto en este proyecto aporte nuevas ideas para pensar problemas de filosofía de la matemática. Un ejemplo de estos posibles aportes puede verse en el trabajo de Arkoudas Computers, Justi?cation, and Mathematical Knowledge el cual echa nueva luz al problema del significado de las demostraciones matemáticas.Los objetivos del proyecto son: Caracterizar el campo de las ciencias de la computación.Evaluar los fundamentos ontológicos, epistemológicos y metodológicos de la ciencia de la computación actual.Analizar las relaciones entre las diferentes perspectivas heurísticas y epistémicas y las practicas de la programación.
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Monitoring, object-orientation, real-time, execution-time, scheduling
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En este proyecto se han visto dos sistemas de computación distribuida diferentes entre ellos: Condor y BOINC. Se exploran las posibilidades para poder conseguir que ambos sistemas logren trabajar conjuntamente, escogiendo la parte más efectiva de cada uno de los sistemas con el fin de complementarse.
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Time-inconsistency is an essential feature of many policy problems (Kydland and Prescott, 1977). This paper presents and compares three methods for computing Markov-perfect optimal policies in stochastic nonlinear business cycle models. The methods considered include value function iteration, generalized Euler-equations, and parameterized shadow prices. In the context of a business cycle model in which a scal authority chooses government spending and income taxation optimally, while lacking the ability to commit, we show that the solutions obtained using value function iteration and generalized Euler equations are somewhat more accurate than that obtained using parameterized shadow prices. Among these three methods, we show that value function iteration can be applied easily, even to environments that include a risk-sensitive scal authority and/or inequality constraints on government spending. We show that the risk-sensitive scal authority lowers government spending and income-taxation, reducing the disincentive households face to accumulate wealth.
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Nowadays, service providers in the Cloud offer complex services ready to be used as it was a commodity like water or electricity to their customers with any other extra effort for them. However, providing these services implies a high management effort which requires a lot of human interaction. Furthermore, an efficient resource management mechanism considering only provider's resources is, though necessary, not enough, because the provider's profit is limited by the amount of resources it owns. Dynamically outsourcing resources to other providers in response to demand variation avoids this problem and makes the provider to get more profit. A key technology for achieving these goals is virtualization which facilitates provider's management and provides on-demand virtual environments, which are isolated and consolidated in order to achieve a better utilization of the provider's resources. Nevertheless, dealing with some virtualization capabilities implies an effort for the user in order to take benefit from them. In order to avoid this problem, we are contributing the research community with a virtualized environment manager which aims to provide virtual machines that fulfils with the user requirements. Another challenge is sharing resources among different federated Cloud providers while exploiting the features of virtualization in a new approach for facilitating providers' management. This project aims for reducing provider's costs and at the same time fulfilling the quality of service agreed with the customers while maximizing the provider's revenue. It considers resource management at several layers, namely locally to each node in the provider, among different nodes in the provider, and among different federated providers. This latter layer supports the novel capabilities of outsourcing when the local resources are not enough to fulfil the users demand, and offering resources to other providers when the local resources are underused.
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Hypergraph width measures are a class of hypergraph invariants important in studying the complexity of constraint satisfaction problems (CSPs). We present a general exact exponential algorithm for a large variety of these measures. A connection between these and tree decompositions is established. This enables us to almost seamlessly adapt the combinatorial and algorithmic results known for tree decompositions of graphs to the case of hypergraphs and obtain fast exact algorithms. As a consequence, we provide algorithms which, given a hypergraph H on n vertices and m hyperedges, compute the generalized hypertree-width of H in time O*(2n) and compute the fractional hypertree-width of H in time O(1.734601n.m).1
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The Public Health Agency is advising that the plume of volcanic ash over the north Atlantic is not currently a risk to public health in Northern Ireland. The previous eruption of the Eyjafjallajokull Icelandic volcano in April 2010 had no impact on public health in the UK and a study of respiratory and related symptoms reported to GPs in the UK in 2010 showed no unusual increases during the period in which the volcanic dust from Iceland was present in the atmosphere.In view of the present dynamic weather conditions across the UK the PHA is liaising closely with health protection colleagues in England, Scotland, Wales and the Met Office in relation to the latest available scientific information on the volcanic ash.For more information visit www.hpa.org.uk
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El projecte que es presenta a continuació és una planificació de migració de servidors físics a un entorn virtualitzat, allà on sigui possible. A més s'ha plantejat una renovació tecnològica de tot el parc de servidors per estalviar diners en el manteniment i en el consum d'energia.La solució de virtualització es buscarà que sigui programari lliure.
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Technological limitations and power constraints are resulting in high-performance parallel computing architectures that are based on large numbers of high-core-count processors. Commercially available processors are now at 8 and 16 cores and experimental platforms, such as the many-core Intel Single-chip Cloud Computer (SCC) platform, provide much higher core counts. These trends are presenting new sets of challenges to HPC applications including programming complexity and the need for extreme energy efficiency.In this work, we first investigate the power behavior of scientific PGAS application kernels on the SCC platform, and explore opportunities and challenges for power management within the PGAS framework. Results obtained via empirical evaluation of Unified Parallel C (UPC) applications on the SCC platform under different constraints, show that, for specific operations, the potential for energy savings in PGAS is large; and power/performance trade-offs can be effectively managed using a cross-layerapproach. We investigate cross-layer power management using PGAS language extensions and runtime mechanisms that manipulate power/performance tradeoffs. Specifically, we present the design, implementation and evaluation of such a middleware for application-aware cross-layer power management of UPC applications on the SCC platform. Finally, based on our observations, we provide a set of recommendations and insights that can be used to support similar power management for PGAS applications on other many-core platforms.
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In this work, we have developed the first free software for mobile devices with the Android operating system that can preventively mitigate the number of contagions of sexually transmitted infections (STI), associated with risk behavior. This software runs in two modes. The normal mode allows the user to see the alerts and nearby health centers. The second mode enables the service to work in the background. This software reports the health risks, as well as the location of different test centers.
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Référence bibliographique : Rol, 55042