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71.
72.
J. Weise Dr.‐Ing. O. Yezerska M. Busse M. Haesche V. Zanetti‐Bueckmann M. Schmitt 《Materialwissenschaft und Werkstofftechnik》2007,38(11):901-906
Micro‐porous syntactic foams were produced by means of integration of glass bubbles into aluminium and zinc matrices. Preforms of glass bubbles were pressure infiltrated with the alloys AlSi9Cu9 ans ZnAl4Cu using squeeze casting. The preforms were sintered thermically without the use of bonding agents. Using the combination of different sintering steps syntactic foams with locally different densities could be produced. The mechanical properties of the foams were tested indicating a high compression strength of the foams and a very good compression energy absorption. Furthermore, corrosion behaviour and behaviour at higher temperatures were investigated. 相似文献
73.
We define the very rich language of composed conditionals on a three‐valued logic and use this language as the communication tool between man and machine. Communication takes place for three reasons: knowledge acquisition, query, and response. Learning, thinking, and answering questions are of a pure information theoretical nature. The pivot of this knowledge processing concept is the amount of information (bit) we receive if a conditional becomes true. We follow an axiomatic approach to information theory rather than the classical probabilistic approach of Shannon; information comes first, and then comes probability. In the light of this philosophy, query and response experience new interpretations. Both, acquisition and response are realized by maximizing entropy and minimizing relative entropy, respectively. The iterative solution of these mathematical optimization problems gives new insights into the adaptation of prior knowledge to new information. Our expert system shell SPIRIT supports this kind of knowledge processing, which will be established by suitable examples. © 2003 Wiley Periodicals, Inc. 相似文献
74.
Wood has long traditions as a building material, and is often used in construction elements, and as interior and exterior surfaces in the Nordic countries. In most applications, there are reaction to fire requirements to products used as surfaces, e.g. in escape routes and larger public spaces. Most wood products will therefore have to be treated with fire retardant (FR) agents to fulfil the strict requirements to properties connected to heat release and flame spread. Unfortunately, FR agents usually also increase the smoke production, as they cause a more incomplete combustion of the wood. The wood product manufacturers seek to find the optimal amount of FR additives where both heat release and smoke production in the classifying test are within the requirements given in the building regulations. This paper describes models for prediction of the European reaction to fire classes of wood products. The models are based on multivariate statistical analysis, and use test results from the cone calorimeter test as input. The presented models are, with very good precision, able to predict which Euroclass and additional smoke class a wood based product would obtain if it were to be tested in the single burning item test. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
75.
We will analyze the economic sensitivity of new energy-saving technologies to weather, future energy price, and system lifetime uncertainties. Graphical rate of return analysis is employed. A representative residential solar water heating investment is analyzed to illustrate the impact of uncertainties. The wide range of reasonable rates of return found suggests some considerations for policy makers and some areas of future research. 相似文献
76.
Previous papers have demonstrated that low-cost off-peak electricity can be used to provide auxiliary heating for a passive-solar-heated residence. This paper describes the development of optimal control strategies for the operation of this auxiliary heating system. The temperature in the residence throughout the day as determined by computer simulation is presented for several optimal and conventional control strategies. The optimal control strategies improved the temperature control in the building compared to the conventional strategies. All strategies were shown to depend heavily on weather prediction. Computer simulations showed that errors in weather prediction had a small effect on heating cost and a large effect on being able to maintain the desired indoor temperature. 相似文献
77.
Prentky Robert A.; Knight Raymond A.; Lee Austin F. S. 《Canadian Metallurgical Quarterly》1997,65(1):141
This study examined the predictive efficacy of 10 rationally derived, archivally coded variables for assessing reoffense risk among extrafamilial child molesters. Follow-up data on 111 child molesters who were discharged from the Massachusetts Treatment Center between 1960 and 1984 were used. Degree of sexual preoccupation with children, paraphilias, and number of prior sexual offenses predicted sexual recidivism. Juvenile and adult antisocial behavior, paraphilias, and low amount of contact with children predicted nonsexual victim-involved and violent recidivism. Area under the receiver-operating characteristic curves in all three analyses indicated discrimination that was substantially better than chance, ranging from .73 to .79. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Reports an error in "Does reward increase or decrease creativity" by Robert Eisenberger and Michael Selbst (Journal of Personality and Social Psychology, 1994[Jun], Vol 66[6], 1116-1127). In the aforementioned article, Figures 1 and 2 were interchanged. The figures appear with their correct captions in the erratum. (The following abstract of the original article appeared in record 1994-40652-001.) Two studies involving 504 school children investigated why behaviorists and cognitively oriented investigators have come to opposite conclusions about reward's effects on creativity. A monetary reward for a high degree of divergent thought in 1 task (word construction) increased children's subsequent originality in a different task (picture drawing). The same reward, made contingent on a low degree of divergent thought, reduced this generalized originality. These effects were eliminated by using a large reward and were restored by keeping the large reward out of the children's sight. The results suggest that reward training increases generalized creativity when (1) a high degree of divergent thought is required and (2) the reward is presented in not too salient a fashion. The findings are consistent with a 2-factor interpretation of rewarded creativity effects that incorporates learned industriousness and selective attention. [A correction concerning this article appears in Journal of Personality & Social Psychology, 1994(Jul), Vol 67(1), 125. Figures 1 and 2 were interchanged.] (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
The question of "What makes things seem similar?" is important both for the pivotal role of similarity in theories of cognition and for an intrinsic interest in how people make comparisons. Similarity frequently involves more than listing the features of the things to be compared and comparing the lists for overlap. Often, the parts of one thing must be aligned or placed in correspondence with the parts of the other. The quantitative model with the best overall fit to human data assumes an interactive activation process whereby correspondences between the parts of compared things mutually and concurrently influence each other. An essential aspect of this model is that matching and mismatching features influence similarity more if they belong to parts that are placed in correspondence. In turn, parts are placed in correspondence if they have many features in common and if they are consistent with other developing correspondences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.