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Reference Data Set (reference + data_set)
Selected AbstractsEvaluation of Uncertainties Associated with Geocoding TechniquesCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2004Hassan A. Karimi Geocoded data play a major role in numerous engineering applications such as transportation and environmental studies where geospatial information systems (GIS) are used for spatial modeling and analysis as they contain spatial information (e.g., latitude and longitude) about objects. The information that a GIS produces is impacted by the quality of the geocoded data (e.g., coordinates) stored in its database. To make appropriate and reasonable decisions using geocoded data, it is important to understand the sources of uncertainty in geocoding. There are two major sources of uncertainty in geocoding, one related to the database that is used as a reference data set to geocode objects and one related to the interpolation technique used. Factors such as completeness, correctness, consistency, currency, and accuracy of the data in the reference database contribute to the uncertainty of the former whereas the specific logic and assumptions used in an interpolation technique contribute to the latter. The primary purpose of this article is to understand uncertainties associated with interpolation techniques used for geocoding. In doing so, three geocoding algorithms were used and tested and the results were compared with the data collected by the Global Positioning System (GPS). The result of the overall comparison indicated no significant differences between the three algorithms. [source] ICOADS release 2.1 data and productsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2005Steven J. Worley Abstract The International Comprehensive Ocean,Atmosphere Data Set (ICOADS), release 2.1 (1784,2002), is the largest available set of in situ marine observations. Observations from ships include instrument measurements and visual estimates, and data from moored and drifting buoys are exclusively instrumental. The ICOADS collection is constructed from many diverse data sources, and made inhomogeneous by the changes in observing systems and recording practices used throughout the period of record, which is over two centuries. Nevertheless, it is a key reference data set that documents the long-term environmental state, provides input to a variety of critical climate and other research applications, and serves as a basis for many associated products and analyses. The observational database is augmented with higher level ICOADS data products. The observed data are synthesized to products by computing statistical summaries, on a monthly basis, for samples within 2° latitude × 2° longitude and 1° × 1° boxes beginning in 1800 and 1960 respectively. For each resolution the summaries are computed using two different data mixtures and quality control criteria. This partially controls and contrasts the effects of changing observing systems and accounts for periods with greater climate variability. The ICOADS observations and products are freely distributed worldwide. The standard ICOADS release is supplemented in several ways; additional summaries are produced using experimental quality control, additional observations are made available in advance of their formal blending into a release, and metadata that define recent ships' physical characteristics and instruments are available. Copyright © 2005 Royal Meteorological Society [source] Scaling of one-shot oscillation images with a reference data setJOURNAL OF SYNCHROTRON RADIATION, Issue 1 2004Kunio Hirata By combining a least-squares procedure with the program MOSFLM, a program SCLONE has been developed which processes diffraction images that do not contain serial oscillation images and may have a few or no full reflections. After each image was processed by MOSFLM, the partialities and structure amplitudes of the reflections were estimated using a least-squares method to refine the scaling factor, the relative temperature factor, the mosaic spread, cell constants, and missetting angles for each independent image. The SCLONE calculation significantly improved the quality of the intensities from the reflections obtained by the initial MOSFLM calculation and crystal structural refinement confirmed the improvement. The SCLONE calculation indicated that the reflection of the present crystal had a rocking curve that was steeper at the middle of the profile and more gradual at both ends of the profile than that assumed in the program MOSFLM. [source] Non-empirical calculations of NMR indirect carbon,carbon coupling constants.MAGNETIC RESONANCE IN CHEMISTRY, Issue 2 2005Part 1, a practical guide to structural elucidation, saturated carbocycles: a reference data set Abstract Carbon,carbon spin,spin coupling constants, J(C,C), calculated at the SOPPA level for 50 mono-, bi- and polycycloalkanes in 10 previous papers are put in order and discussed on unified grounds. Basic structural trends of J(C,C) established in the original publications are summarized and briefly outlined for the representative series. Many unknown couplings are predicted with high reliability, and this provides a good reference data set and a practical guide to the structural elucidation of saturated carbocycles by means of J(C,C) coupling constants. Copyright © 2004 John Wiley & Sons, Ltd. [source] A survey in the park: Methodological and practical problems associated with geophysical investigation in a late Victorian municipal parkARCHAEOLOGICAL PROSPECTION, Issue 3 2010Andrew Parkyn Abstract The survey of Pudsey Park is a geophysical investigation of a late Victorian municipal park. The aim of the survey was to use geophysical techniques to identify the park's changing designs over a 120 year period. An initial design for the park was located during the desk-based assessment, however, it was unclear how much of the original plan had been implemented. It was suspected that Pudsey Park's design has been simplified over time. The project also aimed to identify a suitable sampling strategy for studying park and garden sites by using high-resolution surveys and multiple probe separations for varying depths of detection during earth resistance survey. It was hoped that multiple electrode separations combined with a high density survey could be used to differentiate the signal responses from the modern park designs and earlier design schemes. The choice of strategy is at a significantly higher resolution than guidelines for geophysical investigations for traditional archaeological features. The survey provided highly detailed but complicated data sets; areas of the park have had several redesigns, often where the modern scheme masks previous designs. A number of ,hard' and ,soft' landscaping features were identified including the foundations of the original bandstand (now replaced) and former flower beds. The 0.25,m probe separation surprisingly produced the most defined data with the greatest level of information due to the increased spatial resolution. The geophysical investigation is the first of its kind to investigate a Victorian municipal park in its entirety. The survey validates the importance of high-resolution survey in the study of parks and gardens and also provides a reference data set for future work where poorer documentation hinders interpretation. The geophysics data, together with the accompanying Geographical Information System database produce a unique and detailed picture of a Victorian park from its inception through 120 years of development. Copyright © 2010 John Wiley & Sons, Ltd. [source] High-resolution X-ray crystal structure of bovine H-protein at 0.88,Å resolutionACTA CRYSTALLOGRAPHICA SECTION D, Issue 6 2010Akifumi Higashiura Recent technical improvements in macromolecular X-ray crystallography have significantly improved the resolution limit of protein structures. However, examples of high-resolution structure determination are still limited. In this study, the X-ray crystal structure of bovine H-protein, a component of the glycine cleavage system, was determined at 0.88,Å resolution. This is the first ultrahigh-resolution structure of an H-protein. The data were collected using synchrotron radiation. Because of limitations of the hardware, especially the dynamic range of the CCD detector, three data sets (high-, medium- and low-resolution data sets) were measured in order to obtain a complete set of data. To improve the quality of the merged data, the reference data set was optimized for merging and the merged data were assessed by comparing merging statistics and R factors against the final model and the number of visualized H atoms. In addition, the advantages of merging three data sets were evaluated. The omission of low-resolution reflections had an adverse effect on visualization of H atoms in hydrogen-omit maps. Visualization of hydrogen electron density is a good indicator for assessing the quality of high-resolution X-ray diffraction data. [source] | |||||||||||||