8,250 research outputs found

    Grounding semantic web services with rules

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    Semantic web services achieve effects in the world through web services, so the connection to those services - the grounding - is of paramount importance. The established technique is to use XML-based translations between ontologies and the SOAP message formats of the services, but these mappings cannot address the growing number of non-SOAP services, and step outside the ontological world to describe the mapping. We present an approach which draws the service's interface into the ontology: we define ontology objects which represent the whole HTTP message, and use backward-chaining rules to translate between semantic service invocation instances and the HTTP messages passed to and from the service. We present a case study using Amazon's popular Simple Storage Service

    TECHNOLOGICAL CHANGE IN MEAT AND POULTRY-PACKING AND PROCESSING

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    Nonparametric procedures are used to compare technological change in SIC 2011, meatpacking, and SIC 2015, poultry slaughter and processing. There has been a greater increase in total factor productivity in poultry than in the red meats. Evidence also suggests recent differences in the bias of this technological change, with production changes being labor using in poultry and biased towards greater efficiency in the use of live animal inputs in meatpacking.Red meat, Poultry, Meatpacking, Technological change, Nonparametric analysis, Livestock Production/Industries, Research and Development/Tech Change/Emerging Technologies,

    A COMPARISON OF DEPARTMENTAL TEACHING EFFICIENCY IN THE COLLEGE OF AGRICULTURE, FOOD SYSTEMS, AND NATURAL RESOURCES: AY2000-AY2004

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    Teaching efficiency is investigated for the nine departments in the College of Agriculture, Food Systems, and Natural Resources at North Dakota State University. Using Data Envelopment Analysis, departments are compared to their College peers in converting teaching faculty and teaching funds into three teaching outputs: student credit hours generated, undergraduate majors, and graduate students. Most departments are efficient in the technical conversion of inputs to outputs under variable returns to scale. Scale effects are evident, indicating some departments consistently extract higher average productivity from inputs in servicing undergraduate majors, graduate students, and in generating student credit hours.Teaching/Communication/Extension/Profession,

    Atmospheric composition of weak G band stars: CNO and Li abundances

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    We determined the chemical composition of a large sample of weak G band stars -- a rare class of G and K giants of intermediate mass with unusual abundances of C, N, and Li. We have observed 24 weak G band stars with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory and derived spectroscopic abundances for C, N, O, and Li, as well as for selected elements from Na - Eu. The results show that the atmospheres of weak G band stars are highly contaminated with CN-cycle products. The C underabundance is about a factor of 20 larger than for normal giants and the 12^{12}C/13^{13}C ratio approaches the CN-cycle equilibrium value. In addition to the striking CN-cycle signature the strong N overabundance may indicate the presence of partially ON-cycled material in the atmospheres of the weak G band stars. The exact mechanism responsible for the transport of the elements to the surface has yet to be identified but could be induced by rapid rotation of the main sequence progenitors of the stars. The unusually high Li abundances in some of the stars are an indicator for Li production by the Cameron-Fowler mechanism. A quantitative prediction of a weak G band star's Li abundance is complicated by the strong temperature sensitivity of the mechanism and its participants. In addition to the unusual abundances of CN-cycle elements and Li we find an overabundance of Na that is in accordance with the NeNa chain running in parallel with the CN-cycle. Apart from these peculiarities the element abundances in a weak G band star's atmosphere are consistent with those of normal giants.Comment: 18 pages, 18 figures, accepted for publication in Ap

    Carbon and Oxygen abundances across the Hertzsprung gap

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    We derived atmospheric parameters and spectroscopic abundances for C and O for a large sample of stars located in the Hertzsprung gap in the Hertzsprung-Russell Diagram in order to detect chemical peculiarities and get a comprehensive overview of the population of stars in this evolutionary state. We have observed and analyzed high resolution spectra (R = 60 000) of 188 stars in the mass range 2 - 5 Msun with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory including 28 stars previously identified as Am/Ap stars. We find that the C and O abundances of the majority of stars in the Hertzsprung gap are in accordance with abundances derived for local lower mass dwarfs but detect expected peculiarities for the Am/Ap stars. The C and O abundances of stars with Teff < 6500 K are slightly lower than for the hotter objects but the C/O ratio is constant in the analyzed temperature domain. No indication of an alteration of the C and O abundances of the stars by mixing during the evolution across the Hertzsprung gap could be found before the homogenization of their atmospheres by the first dredge-up.Comment: 13 pages, 12 figures, accepted for publication in the Astrophysical Journa

    Dyonic Instantons in Five Dimensional Gauge Theories

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    We show that there exist finite energy, non-singular instanton solutions for five-dimensional theories with broken gauge symmetry. The soliton is supported against collapse by a non-zero electric charge. The low-energy dynamics of these solutions is described by motion on the ADHM moduli space with potential.Comment: 9 pages. Latex. Minor typos, including correction to final equatio
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