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1.
Combining multiple knowledge bases 总被引:2,自引:0,他引:2
Combining knowledge present in multiple knowledge base systems into a single knowledge base is discussed. A knowledge based system can be considered an extension of a deductive database in that it permits function symbols as part of the theory. Alternative knowledge bases that deal with the same subject matter are considered. The authors define the concept of combining knowledge present in a set of knowledge bases and present algorithms to maximally combine them so that the combination is consistent with respect to the integrity constraints associated with the knowledge bases. For this, the authors define the concept of maximality and prove that the algorithms presented combine the knowledge bases to generate a maximal theory. The authors also discuss the relationships between combining multiple knowledge bases and the view update problem 相似文献
2.
Pilot simplex experiments for improving the tablet strength of three aspirin tablet formulations based on precompression and compression forces were presented. As each simplex moved towards the direction of the optimum, the friability was being minimized and the crushing strength was concomittantly being maximized. Because it followed a systematic direction, simplex process would locate a local optimum rapidly. The appropriate levels of precompression and compression forces that produced tablets with the desired strength were attained in five trials. By contrast, random search for this force combination required at least ten trials. Simplex technique is a cost and time effective means for determining the precompression and compression forces that will reduce the friability or increase the hardness of a tablet formulation. Results appeared to also indicate that crushing strength might be a more reliable measure of tablet strength than friability. 相似文献
3.
Amanda Alliband Daniel W. Lenz Laura E. Stevenson Travis Whitmer Rex Cash Dennis Burns Sarah Hall William T.K. Stevenson 《Progress in Organic Coatings》2008
A model has been proposed to explain the failure of the original BMS10-39 epoxy paint on upper vertical surfaces in B-52 fuel tanks. The model involves interaction of the paint with DIEGME, a fuel system ice inhibitor (FSII) in jet fuel, that is distilled from the liquid fuel. In this communication, distillation experiments used to support the model are refined to better match the mass transfer of vapor from fuel in a B-52 fuel tank at close to room temperature. The interaction of these lower temperature distillates with the paint affirms the earlier model. On the basis of these experiments it is proposed that paint failure may be controlled or eliminated by reducing the level of DIEGME in the fuel. Proposed changes in military jet fuel composition are detailed. 相似文献
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Beliefs, time and incomplete information in multiple encounter negotiations among autonomous agents 总被引:1,自引:0,他引:1
Sarit Kraus 《Annals of Mathematics and Artificial Intelligence》1997,20(1-4):111-159
In negotiations among autonomous agents over resource allocation, beliefs about opponents, and about opponents’ beliefs, become
particularly important when there is incomplete information. This paper considers interactions among self‐motivated, rational,
and autonomous agents, each with its own utility function, and each seeking to maximize its expected utility. The paper expands
upon previous work and focuses on incomplete information and multiple encounters among the agents. It presents a strategic
model that takes into consideration the passage of time during the negotiation and also includes belief systems. The paper
provides strategies for a wide range of situations. The framework satisfies the following criteria: symmetrical distribution,
simplicity, instantaneously, efficiency and stability.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Cryogenic detectors with superconducting tunnel junctions can provide an energy resolution improved by at least one order of magnitude compared with standard semiconductor detectors. While the detection principle was already demonstrated many years ago, the past years were dedicated to the transition from the laboratory sample to practical detectors. Our most favored detector design gives rise to tunnel junctions with electrodes of unequal energy gaps. In such hetero tunnel junctions bias conditions can be established which cause a negative signal current. We report the experimental verification of this effect, and we discuss the yield of charge signal of cryogenic detectors based upon superconducting tunnel junctions. 相似文献
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In 1873, when James Clerk Maxwell published his treatise unifying electromagnetic theory, he stated that light was electromagnetic in nature and he predicted that electromagnetic waves of greater length might exist. A dozen years later, Heinrich Hertz constructed apparatus with which he generated and received these longer waves, and he demonstrated that their behavior was identical to that of light. In the century following Hertz, these longer waves, which we now call radio waves, have been utilized to provide a vast worldwide communication system. In his theory of general relativity, published in 1915, Albert Einstein postulated the existence of gravity waves that propagate at the speed of light. If these waves could be used for communication purposes, they would open a whole new spectrum for exploitation, independent of the electromagnetic spectrum. Why is it that today, three quarters of a century later, we don't have gravity-wave transmitting and receiving stations? The article examines the reasons for this and then determines quantitatively how far we are from adding gravity waves to our communications repertoire 相似文献
10.
Lowe Rob; Bennett Paul; Walker Ian; Milne Sarah; Bozionelos George 《Canadian Metallurgical Quarterly》2003,22(5):464
The theory of planned behavior suggests attitudes are a product of salient beliefs. This study examined whether aggregating salient beliefs was plausible within a more biologically centered information-processing environment. A neural network was used to examine associations among beliefs relating to exercise intention. Data on intentions and behavioral, normative, and control beliefs from 114 respondents were used to train (by error backpropagation) a neural network to associate beliefs with intention. The R2 between the network's estimated and self-reported intention was .66. The network's representation comprised 6 belief profiles associated with high, moderate, or low behavioral intention. The neural network accommodated complex relationships among beliefs and belief-intention associations and indicated how high-level constructs such as attitudes may be viewed as the best fit (compromise state) between aroused beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献