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21.
The investigation of microstructure, some electrical and optical parameters of transparent ThO2-15 mol % yo1.5 ceramics has shown: (a) a very low porosity, close to zero; (b) a higher electrical conductivity than is usual for ThO2 ceramics of the same composition, with the activation energy 1.12 eV; (c) a relative permittivity r 33 under the given conditions; (d) confirmation of a single-phase fluorite-type cubic structure by means of Raman and infrared spectra.  相似文献   
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The provision of support for holistic operations in the scope of a horizontal digital administration requires the fulfillment of a number of previous steps that guarantee the viability of services in the domain. One of these tasks is the proper management of documents. Documents are a key element of any democratic administration and their digital management is a clear pre-requisite for the arrival of digital government. This article tackles how this service can be provided using the support of semantics as a technological cornerstone. The implementation of such a tool is made through the so-called cPortfolio. This platform is deeply discussed and details about its design and implementation are provided. This system is designed to manage both the personal information from the citizen and the documents they possess. Tests on the prototype showed interesting features regarding the simplicity of use and the interoperability support provided to third party agents.  相似文献   
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One of the applications of workflow systems is the management of administrative processes characterized by the transmission of information elements among users of an organization. Tasks contained in these processes are carried out by users responsible for confirming, modifying or adding information throughout. These processes need to be defined in workflow management systems in which all the elements are perfectly identified and are easily adaptable to changes that may arise in the sequences of tasks, in the users involved or in the data transmitted from one task to another. For this kind of processes is easier to reuse those represented in ontologies. On one hand, existing ontologies for representing some domain elements can be reused. At the same time, ontologies have an excellent expressive capacity to define tasks, their relationships and the flow control among them with precision. This paper proposes a complete model, together with the necessary software tools, for tackling this issue.
álvaro E. PrietoEmail:

álvaro E. Prieto   is a teaching/research assistant professor of Computer Science at the University of Extremadura, Spain. He has an MSc in Computer Science from the University of Extremadura (2000). His Ph.D. research addresses the use of ontologies in workflows. He is currently involved in various national and regional R&D&I projects. Adolfo Lozano-Tello   is teaching/research assistant professor of Computer Science Department at University of Extremadura, Spain. He is a Ph.D. (2002) with a special prize of extraordinary thesis about selection of ontologies for software applications. He has published more than 50 papers on the above issues on Software Engineering and Knowledge Engineering.  相似文献   
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Modern demographic situation stressed the problems of human reproductive health associated with industrial medical topics. The article suggests to regard a family (child and two parents) as a unit under study in industrial medicine. This methodic approach should work in scientific programs reviewing influence of industrial ecology and environmental factors on reproductivity. The authors suggest elaboration of universal strategy for ecologic and epidemiologic studies to form a scientific branch "Epidemiology of reproductive health" and to elaborate methods for better health management during the present demographic crisis.  相似文献   
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The authors proved that animals having higher natural antioxidant activity and lower intensity of lipid peroxidation are more resistant to fibrogenic effects of quartz. The peritoneal macrophages obtained from those animals show higher resistance to quartz exposure "in vitro". Parameters characterizing antioxidant system should be included into a group of indexes describing propensity to silicosis.  相似文献   
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In this work we study, design, and evaluate computational methods to support interpretation of statutory terms. We propose a novel task of discovering sentences for argumentation about the meaning of statutory terms. The task models the analysis of past treatment of statutory terms, an exercise lawyers routinely perform using a combination of manual and computational approaches. We treat the discovery of sentences as a special case of ad hoc document retrieval. The specifics include retrieval of short texts (sentences), specialized document types (legal case texts), and, above all, the unique definition of document relevance provided in detailed annotation guidelines. To support our experiments we assembled a data set comprising 42 queries (26,959 sentences) which we plan to release to the public in the near future in order to support further research. Most importantly, we investigate the feasibility of developing a system that responds to a query with a list of sentences that mention the term in a way that is useful for understanding and elaborating its meaning. This is accomplished by a systematic assessment of different features that model the sentences’ usefulness for interpretation. We combine features into a compound measure that accounts for multiple aspects. The definition of the task, the assembly of the data set, and the detailed task analysis provide a solid foundation for employing a learning-to-rank approach.

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