79,869 research outputs found

    An evaluation of coding methodologies for potential use in the Alabama Resource Information System (ARIS)-transportation study for the state of Alabama

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    Procedures developed for digitizing the transportation arteries, airports, and dock facilities of Alabama and placing them in a computerized format compatible with the Alabama Resource Information System are described. The time required to digitize by the following methods: (a) manual, (b) Telereadex 29 with film reading and digitizing system, and (c) digitizing tablets was evaluated. A method for digitizing and storing information from the U. T. M. grid cell base which was compatible with the system was developed and tested. The highways, navigable waterways, railroads, airports, and docks in the study area were digitized and the data stored. The manual method of digitizing was shown to be best for small amounts of data, while the graphic input from the digitizing tablets would be the best approach for entering the large amounts of data required for an entire state

    Are geometric morphometric analyses replicable? Evaluating landmark measurement error and its impact on extant and fossil Microtus classification.

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    Geometric morphometric analyses are frequently employed to quantify biological shape and shape variation. Despite the popularity of this technique, quantification of measurement error in geometric morphometric datasets and its impact on statistical results is seldom assessed in the literature. Here, we evaluate error on 2D landmark coordinate configurations of the lower first molar of five North American Microtus (vole) species. We acquired data from the same specimens several times to quantify error from four data acquisition sources: specimen presentation, imaging devices, interobserver variation, and intraobserver variation. We then evaluated the impact of those errors on linear discriminant analysis-based classifications of the five species using recent specimens of known species affinity and fossil specimens of unknown species affinity. Results indicate that data acquisition error can be substantial, sometimes explaining >30% of the total variation among datasets. Comparisons of datasets digitized by different individuals exhibit the greatest discrepancies in landmark precision, and comparison of datasets photographed from different presentation angles yields the greatest discrepancies in species classification results. All error sources impact statistical classification to some extent. For example, no two landmark dataset replicates exhibit the same predicted group memberships of recent or fossil specimens. Our findings emphasize the need to mitigate error as much as possible during geometric morphometric data collection. Though the impact of measurement error on statistical fidelity is likely analysis-specific, we recommend that all geometric morphometric studies standardize specimen imaging equipment, specimen presentations (if analyses are 2D), and landmark digitizers to reduce error and subsequent analytical misinterpretations

    Organizational challenges of the semantic web in digital libraries

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    The Semantic Web initiative holds large promises for the future. There is, however, a considerable gap in Semantic Web research between the contributions in the technological field and the research done in the organizational field. This paper examines, from a socio-technical point of view the impact of Semantic Web technology on the strategic, organizational and technological levels. Building on a comprehensive case study at the National Library in Norway our findings indicate that the highest impact will be at the organizational level. The reason is mainly because inter-organizational and cross-organizational structures have to be established to address the problems of ontology engineering, and a development framework for ontology engineering in digital libraries must be examined

    Near real-time stereo vision system

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    The apparatus for a near real-time stereo vision system for use with a robotic vehicle is described. The system is comprised of two cameras mounted on three-axis rotation platforms, image-processing boards, a CPU, and specialized stereo vision algorithms. Bandpass-filtered image pyramids are computed, stereo matching is performed by least-squares correlation, and confidence ranges are estimated by means of Bayes' theorem. In particular, Laplacian image pyramids are built and disparity maps are produced from the 60 x 64 level of the pyramids at rates of up to 2 seconds per image pair. The first autonomous cross-country robotic traverses (of up to 100 meters) have been achieved using the stereo vision system of the present invention with all computing done onboard the vehicle. The overall approach disclosed herein provides a unifying paradigm for practical domain-independent stereo ranging

    Three-dimensional and tomographic imaging device for X-ray and gamma-ray emitting objects

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    An instrument for obtaining quantitative, three-dimensional and tomographic information relating to X-ray and gamma-ray emitting objects and for the orthoscopic viewing of such objects includes a multiple-pinhole aperture plate held spaced from an X-ray or gamma-ray to visible-light converter which is coupled to a visible-light image intensifier. The spacing between the aperture plate and the converter is chosen such that the mini-images of an emitting object formed by the pinholes do not substantially overlap as they impinge on the converter. The output of the image intensifier is digitized by a digitizing camera in terms of position and intensity and fed into a digital computer. The computer may output quantitative information relating to the emitting object directly, such as that relating to tomograms, or provide information in analogue form when coupled with a suitable viewing device to give an orthoscopic, three-dimensional image of the object

    GARFIELD + RCo Digital Upgrade: a Modern Set-up for Mass and Charge Identification of Heavy Ion Reaction Products

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    An upgraded GARFIELD + Ring Counter (RCo) apparatus is presented with improved performances as far as electronics and detectors are concerned. On one side fast sampling digital read out has been extended to all detectors, allowing for an important simplification of the signal processing chain together with an enriched extracted information. On the other side a relevant improvement has been made in the forward part of the setup (RCo): an increased granularity of the CsI(Tl) crystals and a higher homogeneity in the silicon detector resistivity. The renewed performances of the GARFIELD + RCo array make it suitable for nuclear reaction measurements both with stable and with Radioactive Ion Beams (RIB), like the ones foreseen for the SPES facility, where the Physics of Isospin can be studied.Comment: 13 pages, 19 figures - paper submitted to Eur. Phys. J.

    Random function tracer Patent

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    Design and development of random function tracer for obtaining coordinates of points on contour map

    Automatic telemetry checkout system

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    Telemetry checkout station is designed to automatically perform measurements on the vehicle telemetry. Its features include real-time digitizing and computer controlled station setup, data processing, and self-check. The station can handle a wide variety of automatic tests by changing its computer programs

    BGS Sigma 2012 open source user guide

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    The British Geological Survey began developing digital field mapping systems in 1989. However, it was apparent that the commercially available hardware was not suitable at that time. In 2001, we revisited the topic under the System for Integrated Geoscience Mapping (SIGMA) programme. By 2003, BGS had developed a PDA (personal digital assistant) field system, which was superseded in 2005, when we began deploying a beta system on rugged Tablet PCs. The Tablet PC system, which we called BGS•SIGMAmobile was used by BGS in mapping projects across the UK as well as overseas. It first became available in Open Source form, in June 2009 via the BGS website, www.bgs.ac.uk, under an agreement which stipulates that updates and modifications must be supplied to BGS in order to stimulate further developments. In 2011/2012, BGS•SIGMAmobile was rewritten in .NET and combined with our office based mapping software BGS•SIGMAdesktop within ArcGIS 10.x to create BGS•SIGMA 2012. It is envisaged that future releases will be made available from the BGS website incorporating new modules, modifications and upgrades supplied by BGS and external users of the system. This document has been written to guide users through the installation and use of BGS•SIGMA 2012 (mobile and desktop), which is the third free release. We are happy to receive feedback and modifications emailed to [email protected]
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