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排序方式: 共有1258条查询结果,搜索用时 15 毫秒
1.
Warren J. Batchelor Trevor R. Finlayson Anita K. Gross 《Journal of the American Ceramic Society》1993,76(7):1895-1897
The measured plastic deformation of Mg-PSZ under stress contains contributions from both transformation and microcracking. A method is described to separate the contributions from transformation and microcracking for samples deformed in uniaxial tension. Such a separation enables the ratio of the longitudinal to transverse strains arising from the transformation to be estimated. The results are compared to the predictions of the shear–dilatation model of Chen and Reyes-Morel. Serious discrepancies are found between the experimental results and the predictions of the model and the possible reason for this is discussed. 相似文献
2.
This study was designed to investigate the effect of retaining coronal tooth substance on the performance of post-retained core materials, and to compare the fracture resistance of the system with an intact tooth prepared to similar dimensions. Ten teeth restored with post-retained silver amalgam, and 10 teeth restored with silver-glass cermet, all with a retained single wall of coronal tooth substance, were compared with 10 unrestored teeth prepared to similar dimensions when subjected to a shearing load. The results showed no statistically significant difference between the unrestored teeth and those restored with a silver-glass cermet. Whilst the teeth restored with silver amalgam had a significantly higher fracture resistance (P > 0.01) there was greater tendency to root fracture. 相似文献
3.
If multi-agent learning is the answer, what is the question? 总被引:1,自引:0,他引:1
The area of learning in multi-agent systems is today one of the most fertile grounds for interaction between game theory and artificial intelligence. We focus on the foundational questions in this interdisciplinary area, and identify several distinct agendas that ought to, we argue, be separated. The goal of this article is to start a discussion in the research community that will result in firmer foundations for the area.1 相似文献
4.
Synthesis and Characterisation of Some New Ferrocenyl- and Ferrocenylalkynyl-[60]Fullerene Compounds
David J. Cardin Trevor Gibson Jason A. Peel 《Fullerenes, Nanotubes and Carbon Nanostructures》1997,5(4):681-694
We report the synthesis and characterisation of a series of ferrocenylfullerene compounds, and some new ferrocene derivatives required as intermediates. The new fullerene species are Fc-[60]fullerene, (8); Fc-C=C-[60]fullerene, (10); Fc-C=C-C=C-[60]fullerene, (12); and (η-C5H4SiBu3)Fe(η-C5H4)-[60]fullerene, (14). 相似文献
5.
S.B. Burson D. Bradley J. Brockmann E. Copus D. Powers G. Greene C. Alexander 《Nuclear Engineering and Design》1989,115(2-3)
The NRC's Research Program on Core-Debris/Cavity Interactions comprises two principal elements: (1) an analytical effort focused primarily on development of computer codes needed to predict the potential consequences of risk-significant severe-accident scenarios; and (2) an experimental component to provide insights into the relevant phenomenological processes and to develop the experimental data base necessary for validation of the codes. The analytical activities at Sandia National Laboratories (SNL) focus primarily on refinement and validation of the CORCON and VANESA codes. Two major experimental activities are also based at SNL: (1) the large-scale SURC tests address the thermal-hydraulic phenomena in the cavity as well as aerosol release associated with prototypical core-melt materials in various types of concrete crucibles, while (2) the WITCH and GHOST experiments are concerned with aerosol generation and radionuclide release phenomena. A program of small-scale special-effects tests at Brookhaven National Laboratory (BNL) is coupled to a concomitant model-development and code-validation activity. In addition, measurements are being made at Battelle Columbus Laboratory (BCL) to augment the thermochemical data base needed in the VANESA code to permit refined radiological source-term predictions. The current scope and status of this research is reviewed. 相似文献
6.
J Braungart-Rieker MM Garwood BP Powers PC Notaro 《Canadian Metallurgical Quarterly》1998,34(6):1428-1437
This laboratory study examined mothers' and fathers' sensitivity during face-to-face interactions with their infants as well as infants' affective and regulatory responses during mother-infant versus father-infant still face (SF). The degree to which infant gender and temperament as well as parental sensitivity predicted SF responses was also examined. Participants included 94 healthy, primarily White, middle-class 4-month-olds and their parents. Results indicated that mothers and fathers were equally sensitive toward their infants. Infants' affect and regulatory behaviors were also significantly stable across mother- and father-infant SF situations, although several differences in mean levels of regulation emerged. Finally, the extent to which exogenous and endogenous variables predicted infant SF responses differed as a function of which affect or regulatory variable was being examined and with which parent the infant was experiencing SF. 相似文献
7.
Trevor A. Williams 《Computer Supported Cooperative Work (CSCW)》1995,4(4):281-296
This paper examines whether information technology can play a strategic role in supporting regulatory reforms aimed at achieving
voluntary cooperation with government regulation. Analysis of the case of electronic tax return lodgment in Australia suggests
that the effects of IT are contextual, and identifies positive effects of the new IT system on voluntary cooperation. However,
in this case, divergence between private and public interests and uncertainty and lack of participation in regulatory decision-making
appear to restrict the development of voluntary cooperation as a primary basis for government regulation. 相似文献
8.
9.
Trevor Bench-Capon Katie Atkinson Peter McBurney 《Autonomous Agents and Multi-Agent Systems》2012,25(1):183-208
In this paper we demonstrate how a qualitative framework for decision making can be used to model scenarios from experimental
economic studies and we show how our approach explains the results that have been reported from such studies. Our framework
is an argumentation-based one in which the social values promoted or demoted by alternative action options are explicitly
represented. Our particular representation is used to model the Dictator Game and the Ultimatum Game, which are simple interactions
in which it must be decided how a sum of money will be divided between the players in the games. Studies have been conducted
into how humans act in such games and the results are not explained by a decision-model that assumes that the participants
are purely self-interested utility-maximisers. Some studies further suggest that differences in choices made in different
cultures may reflect their day to day behaviour, which can in turn be related to the values of the subjects, and how they
order their values. In this paper we show how these interactions can be modelled in agent systems in a framework that makes
explicit the reasons for the agents’ choices based upon their social values. Our framework is intended for use in situations
where agents are required to be adaptable, for example, where agents may prefer different outcome states in transactions involving
different types of counter-parties. 相似文献
10.