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91.
Our approach for automating the negotiation of business contracts proceeds in three broad steps. First, determine the structure of the negotiation process by applying general knowledge about auctions and domain–specific knowledge about the contract subject along with preferences from potential buyers and sellers. Second, translate the determined negotiation structure into an operational specification for an auction platform. Third, after the negotiation has completed, map the negotiation results to a final contract. We have implemented a prototype which supports these steps by employing a declarative specification (in courteous logic programs) of (1) high–level knowledge about alternative negotiation structures, (2) general–case rules about auction parameters, (3) rules to map the auction parameters to a specific auction platform, and (4) special–case rules for subject domains. We demonstrate the flexibility of this approach by automatically generating several alternative negotiation structures for the domain of travel shopping in a trading agent competition.  相似文献   
92.
We consider how to interpret, filter, and cross-correlate complex-value color (hue and saturation) images by using a single discrete Fourier transform: the spatiochromatic discrete Fourier transform. The model defines new types of spatiochromatic oriented sinusoidal gratings, termed rainbow gratings, which encode the variation of color over space. We demonstrate how color-opponent detectors observed within the vertebrate visual system can be easily defined by linear filters within this representation. This model also allows us to filter and detect both spatial and chromatic patterns in images by using a single cross-correlation procedure. In doing so, we explore a new form of the Cauchy-Schwartz inequality applied to complex-valued scalar products. Results demonstrate the power of this form of spatiochromatic matched filtering in detecting signals embedded in such a significant amount of noise that they are not visible to the unaided human eye.  相似文献   
93.
Polar cap mesospheric winds observed with a Fabry-Perot interferometer with a circle-to-line interferometer optical (FPI/CLIO) system have been compared with measurements from a field-widened Michelson interferometer optimized for E-region winds (ERWIN). Both instruments observed the Meinel OH emission emanating from the mesopause region (~86 km) at Resolute Bay, Canada (74.9 degrees N, 94.9 degrees W). This is the first time, to our knowledge, that winds measured simultaneously from a ground-based Fabry-Perot interferometer and a ground-based Michelson interferometer have been compared at the same location. The FPI/CLIO and ERWIN instruments both have a capability for high temporal resolution (less than 10 min for a full scan in the four cardinal directions and the zenith). Statistical comparisons of hourly mean winds for both instruments by scatterplots show excellent agreement, indicating that the two optical techniques provide equivalent observations of mesopause winds. Small deviations in the measured wind can be ascribed to the different zenith angles used by the two instruments. The combined measurements illustrate the dominance of the 12-h wave in the mesopause winds at Resolute Bay, with additional evidence for strong gravity wave activity with much shorter periods (tens of minutes). Future operations of the two instruments will focus on observation of complementary emissions, providing a unique passive optical capability for the determination of neutral winds in the geomagnetic polar cap at various altitudes near the mesopause.  相似文献   
94.
The objective of this study was to investigate the feasibility of using near-infrared reflectance spectroscopy (NIRS) to determine nutrient concentrations in dairy manures. We assayed diverse dairy manures (n = 107), collected from dairy farms in the northeastern United States (CT, MD, NY, PA, and VA) by conventional means and NIRS for total C, total N, NH3-N, moisture, P, K, and pH. Samples were scanned from 400 to 2498 nm in polyethylene bags on a FOSS-NIR-Systems Model 6500 scanning monochromator equipped with a sample transport device. We developed calibrations using a one-out cross validation procedure under partial least-squares regression. Preliminary results showed that eight samples were outliers either because of inaccurate conventional analysis or because they were uncharacteristic (i.e., two samples had moisture content below 72%, while all others were above 78%). These outliers were removed from further consideration. Final calibration results with the remaining 99 samples demonstrated that NIRS can accurately determine the moisture (r2 = 0.945, root mean squared deviation or RMSD = 1.0%), total C (r2 = 0.950, RMSD = 0.40%), total N (r2 = 0.956, RMSD = 0.030%), and NH3-N (r2 = 0.967, RMSD = 0.013%) concentrations, but not P or K concentrations in dairy manures. In conclusion, NIRS was shown to be a viable alternative to conventional analysis procedures for determining moisture, total C, total N, and NH3-N in a very diverse set of dairy manures.  相似文献   
95.
Effects of sires on lipid composition of subcutaneous adipose tissue and longissimus dorsi muscle were studied using 113 F(1) heifer and steer calves sired by eight Wagyu bulls out of three different cow herds. Wagyu sires were used and grouped as Old (n=6) and New (n =2) sires, respectively, based on the chronological order in which they were imported into the US. Animals were fed a backgrounding diet for 112 days consisting of an 80:20 ratio of roughage:concentrate, then grazed on orchard grass and bluegrass for 84 days, and finished on a 10:90 ratio of roughage:concentrate diet for 231 days in a feedlot. For longissimus dorsi muscle, progeny from Old sires had higher (P<0.05) monounsaturated to saturated fatty acid ratios (MUFA:SFA) than progeny of New sires. There were also differences (P<0.05) among individual sires for polyunsaturated to saturated fatty acid ratio (PUFA:SFA) (0.05-0.08) and MUFA:SFA (1.03-1.21). Progeny of Angus cows at Washington State University (WSU) had lower (P<0.05) MUFA:SFA and lower SFA than progeny of WSU crossbred and commercial cows. Steers had lower (P<0.05) MUFA:SFA and higher (P<0.05) SFA than heifers. For subcutaneous fat, heifers had higher levels (P<0.05) of linoleic acid (C18:2) and PUFA:SFA than the steers. Means for ether extractable fat in longissimus dorsi muscle differed among sires (P<0.05) and ranged from 7.58 to 13.13%. Progeny from WSU Angus cows had higher (P<0.05) ether extractable fat than WSU crossbred and commercial cows. Cholesterol content of longissimus dorsi muscle was not influenced by sire, cow herd or sex (P>0.05).  相似文献   
96.
The folding of a protein-like heteropolymer is studied by using direct simulation of a lattice model that folds rapidly to a well-defined "native" structure. The details of each molecular folding event depend on the random initial conformation as well as the random thermal fluctuations of the polymer. By analyzing the statistical properties of hundreds of folding events, a classical folding "pathway" for such a polymer is found that includes partially folded, on-pathway intermediates that are shown to be metastable equilibrium states of the polymer. These results are discussed in the context of the "classical" and "new" views of folding.  相似文献   
97.
Kinematic data on primate head and neck posture were collected by filming 29 primate species during locomotion. These were used to test whether head and neck posture are significant influences on basicranial flexion and whether the Frankfurt plane can legitimately be employed in paleoanthropological studies. Three kinematic measurements were recorded as angles relative to the gravity vector, the inclination of the orbital plane, the inclination of the neck, and the inclination of the Frankfurt plane. A fourth kinematic measurement was calculated as the angle between the neck and the orbital plane (the head-neck angle [HNA]). The functional relationships of basicranial flexion were examined by calculating the correlations and partial correlations between HNA and craniometric measurements representing basicranial flexion, orbital kyphosis, and relative brain size (Ross and Ravosa [1993] Am. J. Phys. Anthropol. 91:305-324). Significant partial correlations were observed between relative brain size and basicranial flexion and between HNA and orbital kyphosis. This indicates that brain size, rather than head and neck posture, is the primary influence on flexion, while the degree of orbital kyphosis may act to reorient the visual field in response to variation in head and neck posture. Regarding registration planes, the Frankfurt plane was found to be horizontal in humans but inclined in all nonhuman primates. In contrast, nearly all primates (including humans) oriented their orbits such that they faced anteriorly and slightly inferiorly. These results suggest that for certain functional craniometric studies, the orbital plane may be a more suitable registration plane than Frankfurt "Horizontal."  相似文献   
98.
The objective was to investigate the feasibility of using near infrared reflectance spectroscopy to determine the composition of samples generated in situ. Five alfalfa and five orchardgrass hays of differing maturities were incubated for 0, 6, 24, 48, and 72 h (Experiment 1) or for 0, 2, 4, 8, 12, 24, 48, and 96 h (Experiment 2) in rumen-fistulated, lactating cows, using nylon bags. After washing to remove rumen contents, samples were analyzed using a nonrotating circular cell in a scanning monochromator. All samples then were dried at 55 degrees C and analyzed for CP and ADF by wet chemistry and rescanned in the dry state. The degree of DM digestion of the original sample was calculated from duplicate bags. Results for spectral analysis of dried samples (Experiment 1), with one-half the samples for validation, were typical of results found for dry forages. The results for scanning wet samples were less accurate than for dry ones. Analysis of samples from Experiment 2 by equations developed in Experiment 1 often resulted in extremely large biases, but these were corrected by including six samples of each forage from Experiment 2 in the calibration set (from Experiment 1) and redeveloping the equations. Although it is possible to use near infrared reflectance spectroscopy to determine the composition of wet samples generated in situ, results are more accurate if the samples are scanned after drying.  相似文献   
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