914 resultados para Canonical number systems


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This paper presents a multilayered architecture that enhances the capabilities of current QA systems and allows different types of complex questions or queries to be processed. The answers to these questions need to be gathered from factual information scattered throughout different documents. Specifically, we designed a specialized layer to process the different types of temporal questions. Complex temporal questions are first decomposed into simple questions, according to the temporal relations expressed in the original question. In the same way, the answers to the resulting simple questions are recomposed, fulfilling the temporal restrictions of the original complex question. A novel aspect of this approach resides in the decomposition which uses a minimal quantity of resources, with the final aim of obtaining a portable platform that is easily extensible to other languages. In this paper we also present a methodology for evaluation of the decomposition of the questions as well as the ability of the implemented temporal layer to perform at a multilingual level. The temporal layer was first performed for English, then evaluated and compared with: a) a general purpose QA system (F-measure 65.47% for QA plus English temporal layer vs. 38.01% for the general QA system), and b) a well-known QA system. Much better results were obtained for temporal questions with the multilayered system. This system was therefore extended to Spanish and very good results were again obtained in the evaluation (F-measure 40.36% for QA plus Spanish temporal layer vs. 22.94% for the general QA system).

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The development of the Web 2.0 led to the birth of new textual genres such as blogs, reviews or forum entries. The increasing number of such texts and the highly diverse topics they discuss make blogs a rich source for analysis. This paper presents a comparative study on open domain and opinion QA systems. A collection of opinion and mixed fact-opinion questions in English is defined and two Question Answering systems are employed to retrieve the answers to these queries. The first one is generic, while the second is specific for emotions. We comparatively evaluate and analyze the systems’ results, concluding that opinion Question Answering requires the use of specific resources and methods.

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Paper submitted to the 44th European Congress of the European Regional Science Association, Porto, 25-29 August 2004.

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The robotics is one of the most active areas. We also need to join a large number of disciplines to create robots. With these premises, one problem is the management of information from multiple heterogeneous sources. Each component, hardware or software, produces data with different nature: temporal frequencies, processing needs, size, type, etc. Nowadays, technologies and software engineering paradigms such as service-oriented architectures are applied to solve this problem in other areas. This paper proposes the use of these technologies to implement a robotic control system based on services. This type of system will allow integration and collaborative work of different elements that make up a robotic system.

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Closed miscibility gaps in ternary liquid mixtures, at constant temperature and pressure, are obtained if phase separations occur only in the ternary region, whilst all binary mixtures involved in the system are completely miscible. This type of behaviour, although not very frequent, has been observed for a certain number of systems. Nevertheless, we have found no information about the applicability of the common activity coefficient models, as NRTL and UNIQUAC, for these types of ternary systems. Moreover, any of the island type systems published in the most common liquid–liquid equilibrium data collections, are correlated with any model. In this paper, the applicability of the NRTL equation to model the LLE of island type systems is assessed using topological concepts related to the Gibbs stability test. A first attempt to correlate experimental LLE data for two island type ternary systems is also presented.

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In this paper we describe an hybrid algorithm for an even number of processors based on an algorithm for two processors and the Overlapping Partition Method for tridiagonal systems. Moreover, we compare this hybrid method with the Partition Wang’s method in a BSP computer. Finally, we compare the theoretical computation cost of both methods for a Cray T3D computer, using the cost model that BSP model provides.

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This paper deals with stability properties of the feasible set of linear inequality systems having a finite number of variables and an arbitrary number of constraints. Several types of perturbations preserving consistency are considered, affecting respectively, all of the data, the left-hand side data, or the right-hand side coefficients.

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Currently there are an overwhelming number of scientific publications in Life Sciences, especially in Genetics and Biotechnology. This huge amount of information is structured in corporate Data Warehouses (DW) or in Biological Databases (e.g. UniProt, RCSB Protein Data Bank, CEREALAB or GenBank), whose main drawback is its cost of updating that makes it obsolete easily. However, these Databases are the main tool for enterprises when they want to update their internal information, for example when a plant breeder enterprise needs to enrich its genetic information (internal structured Database) with recently discovered genes related to specific phenotypic traits (external unstructured data) in order to choose the desired parentals for breeding programs. In this paper, we propose to complement the internal information with external data from the Web using Question Answering (QA) techniques. We go a step further by providing a complete framework for integrating unstructured and structured information by combining traditional Databases and DW architectures with QA systems. The great advantage of our framework is that decision makers can compare instantaneously internal data with external data from competitors, thereby allowing taking quick strategic decisions based on richer data.

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Commercial off-the-shelf microprocessors are the core of low-cost embedded systems due to their programmability and cost-effectiveness. Recent advances in electronic technologies have allowed remarkable improvements in their performance. However, they have also made microprocessors more susceptible to transient faults induced by radiation. These non-destructive events (soft errors), may cause a microprocessor to produce a wrong computation result or lose control of a system with catastrophic consequences. Therefore, soft error mitigation has become a compulsory requirement for an increasing number of applications, which operate from the space to the ground level. In this context, this paper uses the concept of selective hardening, which is aimed to design reduced-overhead and flexible mitigation techniques. Following this concept, a novel flexible version of the software-based fault recovery technique known as SWIFT-R is proposed. Our approach makes possible to select different registers subsets from the microprocessor register file to be protected on software. Thus, design space is enriched with a wide spectrum of new partially protected versions, which offer more flexibility to designers. This permits to find the best trade-offs between performance, code size, and fault coverage. Three case studies have been developed to show the applicability and flexibility of the proposal.

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The design of fault tolerant systems is gaining importance in large domains of embedded applications where design constrains are as important as reliability. New software techniques, based on selective application of redundancy, have shown remarkable fault coverage with reduced costs and overheads. However, the large number of different solutions provided by these techniques, and the costly process to assess their reliability, make the design space exploration a very difficult and time-consuming task. This paper proposes the integration of a multi-objective optimization tool with a software hardening environment to perform an automatic design space exploration in the search for the best trade-offs between reliability, cost, and performance. The first tool is commanded by a genetic algorithm which can simultaneously fulfill many design goals thanks to the use of the NSGA-II multi-objective algorithm. The second is a compiler-based infrastructure that automatically produces selective protected (hardened) versions of the software and generates accurate overhead reports and fault coverage estimations. The advantages of our proposal are illustrated by means of a complex and detailed case study involving a typical embedded application, the AES (Advanced Encryption Standard).

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We address the optimization of discrete-continuous dynamic optimization problems using a disjunctive multistage modeling framework, with implicit discontinuities, which increases the problem complexity since the number of continuous phases and discrete events is not known a-priori. After setting a fixed alternative sequence of modes, we convert the infinite-dimensional continuous mixed-logic dynamic (MLDO) problem into a finite dimensional discretized GDP problem by orthogonal collocation on finite elements. We use the Logic-based Outer Approximation algorithm to fully exploit the structure of the GDP representation of the problem. This modelling framework is illustrated with an optimization problem with implicit discontinuities (diver problem).

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Thesis (Master, Computing) -- Queen's University, 2016-05-29 18:11:34.114

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This report evaluates the performance of long-term care (LTC) systems in Europe, with a special emphasis on four countries that were selected in Work Package 1 of the ANCIEN project as representative of different LTC systems: Germany, the Netherlands, Spain and Poland. Based on a performance framework, we use the following four core criteria for the evaluation: the quality of life of LTC users, the quality of care, equity of LTC systems and the total burden of LTC (consisting of the financial burden and the burden of informal caregiving). The quality of life is analysed by studying the experience of LTC users in 13 European countries, using data from the Survey of Health, Ageing and Retirement in Europe (SHARE). Older persons with limitations living at home have the highest probability of receiving help (formal or informal) in Germany and the lowest in Poland. Given that help is available, the sufficiency of the help is best ensured in Switzerland, Italy and the Netherlands. The indirectly observed properties of the LTC system are most favourable in France. An older person who considers all three aspects important might be best off living in Belgium or Switzerland. The horizontal and vertical equity of LTC systems are analysed for the four representative countries. The Dutch system scores highest on overall equity, followed by the German system. The Spanish and Polish systems are both less equitable than the Dutch and German systems. To show how ageing may affect the financial burden of LTC, projections until 2060 are given for LTC expenditures for the four representative countries. Under the base scenario, for all four countries the proportions of GDP spent on public and private LTC are projected to more than double between 2010 and 2060, and even treble in some cases. The projections also highlight the large differences in LTC expenditures between the four countries. The Netherlands spends by far the most on LTC. Furthermore, the report presents information for a number of European countries on quality of care, the burden of informal caregiving and other aspects of performance. The LTC systems for the four representative countries are evaluated using the four core criteria. The Dutch system has the highest scores on all four dimensions except the total burden of care, where it has the second-best score after Poland. The German system has somewhat lower scores than the Dutch on all four dimensions. The relatively large role for informal care lowers the equity of the German system. The Polish system excels in having a low total burden of care, but it scores lowest on quality of care and equity. The Spanish system has few extreme scores. Policy implications are discussed in the last chapter of this report and in the Policy Brief based on this report.

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The Common European Asylum System (CEAS) is an EU policy area that is particularly evocative of the ‘politics of numbers’. The European Union has at its disposal a wide array of sources providing detailed information about the capacities and pressures of its member states’ asylum systems. This paper discusses the content of asylum data and the evolving interaction between its different sources, ranging from the United Nations High Commissioner for Refugees to the European Commission’s EUROSTAT and DG HOME, the European Asylum Support Office, FRONTEX, the European Migration Network (EMN) and national databases. However, the way in which such data are often misused, or even omitted, in political debate affects the soundness of policy decisions in the CEAS. Drawing on debates over the contested phenomenon of ‘asylum shopping’ and the exemption of victims of torture and unaccompanied minors from accelerated and border procedures in the recast asylum procedures Directive, this briefing paper argues that solid data-based evidence is often absent from political negotiations on CEAS measures affecting refugees and asylum-seekers.

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After winning the 2010 presidential election, Viktor Yanukovych and his government developed an ambitious and comprehensive programme of reforms across key areas of social and political life. The return to a presidential system of government created the ideal conditions for the introduction of deep reforms: it allowed Viktor Yanukovych to consolidate more power than any other Ukrainian president before him.The authorities launched an overhaul of the tax and the pension systems, and of the Ukrainian gas sector. Kyiv also completed its negotiations on an Association Agreement with the EU and on a Deep and Comprehensive Free Trade Area. However, the reformist zeal of Ukraine’s political elite progressively diminished as the parliamentary election approached, the economy slowed down, and the polls showed a decline in support for the ruling Party of Regions. Many of the reforms still remain in the planning stages, and in many areas the government has moved backwards. Viktor Yanukovych has proved unable to make systemic changes, and has increasingly used his powers to crush political opposition in Ukraine. The outcome of the latest parliamentary elections prevents the formation of a stable parliamentary majority, which in turn, removes any chance of reform before the 2015 presidential ballot.