95,283 research outputs found

    p3d: a general data-reduction tool for fiber-fed integral-field spectrographs

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    The reduction of integral-field spectrograph (IFS) data is demanding work. Many repetitive operations are required in order to convert raw data into, typically a large number of, spectra. This effort can be markedly simplified through the use of a tool or pipeline, which is designed to complete many of the repetitive operations without human interaction. Here we present our semi-automatic data-reduction tool p3d that is designed to be used with fiber-fed IFSs. Important components of p3d include a novel algorithm for automatic finding and tracing of spectra on the detector, and two methods of optimal spectrum extraction in addition to standard aperture extraction. p3d also provides tools to combine several images, perform wavelength calibration and flat field data. p3d is at the moment configured for four IFSs. In order to evaluate its performance we have tested the different components of the tool. For these tests we used both simulated and observational data. We demonstrate that for three of the IFSs a correction for so-called cross-talk due to overlapping spectra on the detector is required. Without such a correction spectra will be inaccurate, in particular if there is a significant intensity gradient across the object. Our tests showed that p3d is able to produce accurate results. p3d is a highly general and freely available tool. It is easily extended to include improved algorithms, new visualization tools and support for additional instruments. The program code can be downloaded from the p3d-project web site http://p3d.sourceforge.netComment: 18 pages, 15 figures, 3 tables, accepted for publication in A&

    HTML Format Tables Extraction with Differentiating Cell Content as Property Name

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    Website presents data in various forms and formats, one of them in the form of a table. Tables on the Internet can be taken such way by copy and paste, but this way is not easy if done on many tables then from extracted result they have been merged with the other tables. This article discussed the research on extraction of HTML tables which stored into a database form. The approach used was algorithm to perform the search process the number of rows and number of columns from the table, and algorithms to perform matching the contents of the table cell extraction results with a Property Name database, so it is unknown whether the extracted table has property in the row/column/table without property. Table and Property Name database displays the data in the Indonesian Language. At pre processing stage Property Name database which is also prepared the techniques to enrich the instance of the Property Name database. The tables in the extract is a table HTML format with a simple table where the form is not found of any merger of the rows and columns in the row position merge 1/column 1. This research provides techniques to enrich the instance of a database, and with the use of illustrations, and then an approach to do the extraction of tabular HTML format can be done in a semi-automatic. In addition to that property in the table which is extracted can be distinguished from the contents of the cell which is a data table

    Ontology-based Information Extraction with SOBA

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    In this paper we describe SOBA, a sub-component of the SmartWeb multi-modal dialog system. SOBA is a component for ontologybased information extraction from soccer web pages for automatic population of a knowledge base that can be used for domainspecific question answering. SOBA realizes a tight connection between the ontology, knowledge base and the information extraction component. The originality of SOBA is in the fact that it extracts information from heterogeneous sources such as tabular structures, text and image captions in a semantically integrated way. In particular, it stores extracted information in a knowledge base, and in turn uses the knowledge base to interpret and link newly extracted information with respect to already existing entities
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