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1.
Stirling W.C. Frost R.L. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2005,35(4):533-543
Social utilities account for agent preferences and, thus, can characterize complex interrelationships, such as cooperation, compromise, negotiation, and altruism, that can exist between agents. Satisficing game theory, which is based on social utilities, offers a framework within which to design sophisticated multiagent systems. Key features of this approach are: a) an N-agent system may be represented by a 2N-dimensional Bayesian network, called a praxeic network; b) the theory accommodates a notion of situational altruism (a willingness to defer to others in a controlled way if so doing would actually benefit others under the condition that others wish to take advantage of such largesse); and c) satisficing games admits a protocol for effective negotiation between agents who, though interested in their own welfare, are also willing to give some deference to others. Three applications are presented. The first two involve well-known two-person games: the Prisoner's Dilemma and the Battle of the Sexes, and the third is a simulated uninhabited aerial vehicle scenario. 相似文献
2.
McKay James R.; Lynch Kevin G.; Shepard Donald S.; Ratichek Sara; Morrison Rebecca; Koppenhaver Janelle; Pettinati Helen M. 《Canadian Metallurgical Quarterly》2004,72(6):967
This study of continuing care for substance dependent patients compared a telephone-based monitoring and brief counseling intervention (TEL) with 2 face-to-face interventions, relapse prevention (RP) and standard 12-step group counseling (STND). The participants were graduates of intensive outpatient programs who had current dependence on alcohol and/or cocaine. Self-report, collateral, and biological measures of alcohol and cocaine use were obtained over a 12-month follow-up. The treatment groups did not differ on abstinence-related outcomes in the complete sample (N = 359) or on cocaine use outcomes in participants with cocaine dependence (n = 268). However, in participants with alcohol dependence only (n = 91), TEL produced better alcohol use outcomes than STND on all measures examined and better outcomes than RP on some of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Chaney John M.; Mullins Larry L.; Wagner Janelle L.; Hommel Kevin A.; Page Melanie C.; Doppler Matthew J. 《Canadian Metallurgical Quarterly》2004,49(2):126
Objective: Examine longitudinal relationships between causal attributions and depression symptoms in adults with rheumatoid arthritis (RA). Study Design: Cross-lagged panel correlations tested the temporal precedence of attributions relative to depression symptoms over 1 year. Participants: Forty-two participants completed self-report instruments on 2 occasions. Main Outcome Measures: The Inventory to Diagnose Depression and the Attributional Style Questionnaire. Results: Time 1 attributions predicted increased levels of depression symptoms at Time 2 after perceived pain and disability were controlled: Time 1 depression symptoms were unrelated to Time 2 attributions. Cross-lagged correlation comparisons revealed statistical dominance for attribution-depression relationships relative to depression-attribution relationships. Conclusions: Results support cognitive diathesis conceptualizations of depression and support cognitive-behavioral treatments for depression in RA. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
4.
The magnetic multipole line-cusp device developed by MacKenzie and associates has been adapted for use as a neutral beam ion source. It has produced high-density, large volume, quiescent, uniform hydrogen plasmas, which makes it a potential candidate for use as a plasma generator for neutral beam injectors. The device is a water-cooled cylindrical copper discharge chamber (25 cm in diameter by 36 cm long) with one end enclosed by a set of extraction grids with a 15-cm-diam multi-aperture pattern. The chamber wall serves as an anode and is surrounded by an external system of rare-earth cobalt magnets arranged in a line-cusp geometry of 12 cusps; plasma is produced by electron emission from a hot cathode assembly. This source has achieved extracted beam currents of 12 A at 18.5 kV, radial plasma density uniformities of +/-5% over a 15-cm diameter, noise levels of less than +/-0.5%, and arc efficiencies (beam current/arc power) of 0.6 A/kW. 相似文献
5.
Chiarello Christine; Welcome Suzanne E.; Halderman Laura K.; Towler Stephen; Julagay Janelle; Otto Ronald; Leonard Christiana M. 《Canadian Metallurgical Quarterly》2009,23(2):210
The authors report findings of a large-scale, multitask investigation of sex differences in both structural asymmetries and lateralization of word reading. Two hundred participants were tested in eight divided visual field lexical tasks, and each received a structural magnetic resonance imaging scan. The authors examined whether there was evidence for sex differences in overall measures of neuroanatomical and behavioral lateralization, in specific language tasks and brain regions, and in variation in asymmetry within and across tasks and brain regions. There was very little evidence for sex differences on any behavioral measure. The few indications of sex differences in the current report accounted for 2% or less of the individual variation in asymmetry and could not be replicated in independent subsamples. No sex differences were observed in the asymmetry of structures in Broca's and Wernicke's areas such as pars triangularis, pars opercularis, the planum temporale, planum parietale, or Heschl's gyrus. There were also no sex differences in the variability of neuroanatomical asymmetries within or between brain regions. However, a significant relationship between planum temporale and behavioral asymmetry was restricted to men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Corrigendum: Mutating a Highly Conserved Residue in Diverse Cytochrome P450s Facilitates Diastereoselective Olefin Cyclopropanation 下载免费PDF全文
7.
The effect of temperature was investigated on the rapid pyrolysis of Prince, Lingan and No. 26 coals in the temperature range of 525° to 750°C using a 600 cm high stainless-steel free fall reactor at atmospheric pressure.
The yields of char, condensibles and gaseous products were determined at 25°C intervals. Gaseous products were analysed for H2, CO, CO2, CH4 and C2+.
Volatile product (condensible and gas) yields exceeded the volatile product in the A.S.T.M. methods at and above 700°C.
Some experiments using Prince coal were repeated at reduced pressure (50 mm mercury) in both the 600 cm height stainless-steel and a 140 cm height quartz reactor in order to find out the effect of pressure and retention time.
The experimental results indicated that the condensable yield was higher at the lower pressure and at the shorter retention time. The effect of retention time was far more pronounced. 相似文献
The yields of char, condensibles and gaseous products were determined at 25°C intervals. Gaseous products were analysed for H2, CO, CO2, CH4 and C2+.
Volatile product (condensible and gas) yields exceeded the volatile product in the A.S.T.M. methods at and above 700°C.
Some experiments using Prince coal were repeated at reduced pressure (50 mm mercury) in both the 600 cm height stainless-steel and a 140 cm height quartz reactor in order to find out the effect of pressure and retention time.
The experimental results indicated that the condensable yield was higher at the lower pressure and at the shorter retention time. The effect of retention time was far more pronounced. 相似文献
8.
Potential use of chemical cues for colony-mate recognition in the big brown bat,Eptesicus fuscus 总被引:1,自引:0,他引:1
Bats should benefit from recognition of their roost-mates when colonies form stable social units that persist over time. We used Y-maze experiments and gas chromatography–olfactometry (GC-O) to evaluate whether female big brown bats Eptesicus fuscus (Chiroptera: Vespertilionidae) use chemical cues to distinguish among conspecifics. In dual-choice Y-maze experiments, females chose the scent of another female from their own roost over a conspecific female from a different roost in a majority of trials. Analysis of total body odors using GC-O suggests that individuals from a given colony may share a more common odor signature with roost-mates than with non-roost-mate conspecifics. Using four principle components derived from 15 odor variables, discriminant function analysis correctly assigned most individuals to the correct colony. 相似文献
9.
M. J. Playne Anna C. Stirling P. McDonald 《Journal of the science of food and agriculture》1967,18(1):19-20
The organic acid composition of aseptically-grown timothy grass (Phleum pratense) was examined. Changes in organic acids of the grass during incubation in small test tubes with and without the addition of lactic acid bacteria were studied. Malic acid, a major acid of the grass, was broken down during incubation mainly by the activity of bacterial enzymes. The amount of succinic acid was increased by the action of both plant and bacterial enzymes. Citric acid was not detected in the aseptically-grown timothy grass but two unidentified acids formed a major part of the total organic acid fraction. 相似文献
10.
Ryan PM Whealton JH Davis RC Stirling WL Tsai CC 《The Review of scientific instruments》1979,50(9):1160-1161
A sciopticon based on the pinhole-camera effect is being used to determine individual beamlet contributions to the quality of neutral beams extracted from multiaperture ion sources. The technique outlined in this note can be used to study the effects on beam optics of nonhomogeneous source plasma density or acceleration gap nonuniformities, grid nonparallelism or aperture misplacement, and space-charge blowup or scattering in the neutralizer cell. 相似文献