47,840 research outputs found
A decision model applied to alcohol effects on driver signal light behavior
A decision model including perceptual noise or inconsistency is developed from expected value theory to explain driver stop and go decisions at signaled intersections. The model is applied to behavior in a car simulation and instrumented vehicle. Objective and subjective changes in driver decision making were measured with changes in blood alcohol concentration (BAC). Treatment levels averaged 0.00, 0.10 and 0.14 BAC for a total of 26 male subjects. Data were taken for drivers approaching signal lights at three timing configurations. The correlation between model predictions and behavior was highly significant. In contrast to previous research, analysis indicates that increased BAC results in increased perceptual inconsistency, which is the primary cause of increased risk taking at low probability of success signal lights
Integrated research in constitutive modelling at elevated temperatures, part 1
Topics covered include: numerical integration techniques; thermodynamics and internal state variables; experimental lab development; comparison of models at room temperature; comparison of models at elevated temperature; and integrated software development
The hydrogen sulfide emissions abatement program at the Geysers Geothermal Power Plant
The scope of the hydrogen sulfide (H2S) abatement program at The Geysers Geothermal Power Plant and the measures currently under way to reduce these emissions are discussed. The Geysers steam averages 223 ppm H2S by weight and after passing through the turbines leaves the plant both through the gas ejector system and by air-stripping in the cooling towers. The sulfide dissolved in the cooling water is controlled by the use of an oxidation catalyst such as an iron salt. The H2S in the low Btu ejector off gases may be burned to sulfur dioxide and scrubbed directly into the circulating water and reinjected into the steam field with the excess condensate. Details are included concerning the disposal of the impure sulfur, design requirements for retrofitting existing plants and modified plant operating procedures. Discussion of future research aimed at improving the H2S abatement system is also included
Integrated research in constitutive modelling at elevated temperatures, part 2
Four current viscoplastic models are compared experimentally with Inconel 718 at 1100 F. A series of tests were performed to create a sufficient data base from which to evaluate material constants. The models used include Bodner's anisotropic model; Krieg, Swearengen, and Rhode's model; Schmidt and Miller's model; and Walker's exponential model
Research on display scanning, sampling, and reconstruction using separate main and secondary tracking tasks
Dynamic model for effects of random scanning and sampling on human operator tracking performanc
Spectral reflectance from plant canopies and optimum spectral channels in the near infrared
Theoretical and experimental aspects of the interaction of light with a typical plant canopy are considered. Both theoretical and experimental results are used to establish optimum electromagnetic wavelength channels for remote sensing in agriculture. The spectral range considered includes half of the visible and much of the near-infrared regions
Cephalopods from the stomachs of sperm whales taken off California
Cephalopod remains (beaks, bodies, and parts of bodies) were
collected from the stomachs of 157 sperm whales (Physeter
macrocephalus) taken off central California (lat. 37°-39°N). At least 24 species representing 14 families were identified. Frequencies of occurrence of the six most numerous taxa were Moroteuthis robusta 72.0%, Gonatopsis borealis 66.2%, Histioteuthis dofleini 36.9%, Galiteuthis spp. (including G. phyllura and G. pacifica) 36.3%, Octopoteuthis deletron 35.0%, and Vampyroteuthis
infernalis 27.4%. One find of two Mesonychoteuthis
hamiltoni beaks strongly suggests transequatorial migration by one large male sperm whale. (PDF file contains 18 pages.
Ab initio mass tensor molecular dynamics
Mass tensor molecular dynamics was first introduced by Bennett [J. Comput.
Phys. 19, 267 (1975)] for efficient sampling of phase space through the use of
generalized atomic masses. Here, we show how to apply this method to ab initio
molecular dynamics simulations with minimal computational overhead. Test
calculations on liquid water show a threefold reduction in computational effort
without making the fixed geometry approximation. We also present a simple
recipe for estimating the optimal atomic masses using only the first
derivatives of the potential energy.Comment: 19 pages, 5 figure
Notes on Miltogramminae with Descriptions of Two New Species
Described from the following material: one male and one female reared from the nest of Bicyrles quadrifasciata Say, taken at Adaton, Mississippi, August, 1922, and three females collected about a Bembicid colony at the same locality (H. W. Allen); one male, Agricultural and Mechanical College, Mississippi, August 7, 1922 (H. W. Allen). In the U.S. National Museum, aside from the type and allotype: one female taken as it emerged from the nest of Bembex spinolae, June 6, 1914, Washington, D.C . (J.B. Parker); one female labeled Parker Note No. 44, concerning which Professor Parker has furnished the information that, this fly was captured as it emerged from the nest of Bicyrtes ventralis. Say, into which it had dashed in pursuit of the wasp as she entered with a Hemipterous insect. A male from Glen Echo, Maryland, August 30, 1923, in the collection of J. R. Malloch. A male and a female taken in coitu, at West Springfield, Massachusetts, July 25, 1915 (H.E. Smith), loaned by the Museum of Comparative Zoology, agree with the type in the number and position of the orbital bristles and in the degree of thickening on the arista, but the front is narrower as in rubriventris, and there are no median marginal bristles on the second abdominal segment in either; also two specimens from the same locality in the collection of the Boston Society of Natural History
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