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Retrieval Techniques (retrieval + techniques)
Selected AbstractsWeb Discovery and Filtering Based on Textual Relevance Feedback LearningCOMPUTATIONAL INTELLIGENCE, Issue 2 2003Wai Lam We develop a new approach for Web information discovery and filtering. Our system, called WID, allows the user to specify long-term information needs by means of various topic profile specifications. An entire example page or an index page can be accepted as input for the discovery. It makes use of a simulated annealing algorithm to automatically explore new Web pages. Simulated annealing algorithms possess some favorable properties to fulfill the discovery objectives. Information retrieval techniques are adopted to evaluate the content-based relevance of each page being explored. The hyperlink information, in addition to the textual context, is considered in the relevance score evaluation of a Web page. WID allows users to provide three forms of the relevance feedback model, namely, the positive page feedback, the negative page feedback, and the positive keyword feedback. The system is domain independent and does not rely on any prior knowledge or information about the Web content. Extensive experiments have been conducted to demonstrate the effectiveness of the discovery performance achieved by WID. [source] Integrating new information and communication technologies in a group decision support systemINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 6 2000N. Karacapilidis Abstract We view group decision making as a collaborative process, where decision makers can establish a common belief on the dimensions of the problem by following a series of well-defined communicative actions. Having first defined these actions, this paper reports on the exploitation of recent advances in information and communication technology, which can be used to: (i) remove the communication impediments among spatially dispersed decision makers; (ii) efficiently elicit and represent the domain of knowledge; (iii) develop efficient mechanisms to structure and consistently maintain the decision analysis; and (iv) automate the decision making process itself. Automation concerns coherence and consistency checking, detection of contradictions, truth maintenance, and information retrieval techniques. [source] Building a reusable test collection for question answeringJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 7 2006Jimmy Lin In contrast to traditional information retrieval systems, which return ranked lists of documents that users must manually browse through, a question answering system attempts to directly answer natural language questions posed by the user. Although such systems possess language-processing capabilities, they still rely on traditional document retrieval techniques to generate an initial candidate set of documents. In this article, the authors argue that document retrieval for question answering represents a task different from retrieving documents in response to more general retrospective information needs. Thus, to guide future system development, specialized question answering test collections must be constructed. They show that the current evaluation resources have major shortcomings; to remedy the situation, they have manually created a small, reusable question answering test collection for research purposes. In this article they describe their methodology for building this test collection and discuss issues they encountered regarding the notion of "answer correctness." [source] Methods for identifying versioned and plagiarized documentsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 3 2003Timothy C. Hoad The widespread use of on-line publishing of text promotes storage of multiple versions of documents and mirroring of documents in multiple locations, and greatly simplifies the task of plagiarizing the work of others. We evaluate two families of methods for searching a collection to find documents that are coderivative, that is, are versions or plagiarisms of each other. The first, the ranking family, uses information retrieval techniques; extending this family, we propose the identity measure, which is specifically designed for identification of coderivative documents. The second, the fingerprinting family, uses hashing to generate a compact document description, which can then be compared to the fingerprints of the documents in the collection. We introduce a new method for evaluating the effectiveness of these techniques, and demonstrate it in practice. Using experiments on two collections, we demonstrate that the identity measure and the best fingerprinting technique are both able to accurately identify coderivative documents. However, for fingerprinting parameters must be carefully chosen, and even so the identity measure is clearly superior. [source] Discriminating raining from non-raining cloud areas at mid-latitudes using meteosat second generation SEVIRI night-time dataMETEOROLOGICAL APPLICATIONS, Issue 2 2008B. Thies Abstract A new method for the delineation of precipitation during night-time using multispectral satellite data is proposed. The approach is not only applicable to the detection of mainly convective precipitation by means of the commonly used relation between infrared cloud-top temperature and rainfall probability but enables also the detection of stratiform precipitation (e.g. in connection with mid-latitude frontal systems). The presented scheme is based on the conceptual model that precipitating clouds are characterized by a combination of particles large enough to fall, an adequate vertical extension [both represented by the cloud water path (CWP)], and the existence of ice particles in the upper part of the cloud. As no operational retrieval exists for Meteosat Second Generation (MSG) to compute the CWP during night-time, suitable combinations of brightness temperature differences (,T) between the thermal bands of Meteosat Second Generation-Spinning Enhanced Visible and InfraRed Imager (MSG SEVIRI, ,T3.9,10.8, ,T3.9,7.3, ,T8.7,10.8, ,T10.8,12.1) are used to infer implicit information about the CWP and to compute a rainfall confidence level. ,T8.7,10.8 and ,T10.8,12.1 are particularly considered to supply information about the cloud phase. Rain area delineation is realized by using a minimum threshold of the rainfall confidence. To obtain a statistical transfer function between the rainfall confidence and the channel differences, the value combination of the channel differences is compared with ground-based radar data. The retrieval is validated against independent radar data not used for deriving the transfer function and shows an encouraging performance as well as clear improvements compared to existing optical retrieval techniques using only IR thresholds for cloud-top temperature. Copyright © 2008 Royal Meteorological Society [source] Modern sperm retrieval techniques and their usefulness in oocyte fertilizationBJU INTERNATIONAL, Issue 2 2001R. Schoysman First page of article [source] | ||||||||||