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141.
142.
Domestic cats (Felis catus) were administered a progressive elimination task in which they had to visit and deplete 3 baited sites. Cats were brought back to the starting point after each visit to any site whether the visit represented a correct or an incorrect choice. The results revealed that cats organized search as a function of the least distance principle whether they had to assess starting point to target distances (Experiment 1, n=12) or adjacent bowl distances (Experiment 2, n=12). The results also revealed that the starting point to target distance factor was the most influential in determining the initial choice (Experiment 3, n=6) and in producing errors. Errors were also linked to the antero-posterior bodily axis of the cat. Results are discussed in terms of the predatory behavior of the cat. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
143.
144.
Refractory Lining for Alumina Electrolytic Cells 总被引:1,自引:0,他引:1
Claude Allaire 《Journal of the American Ceramic Society》1992,75(8):2308-2311
This paper provides the specifications of a refractory lining for alumina electrolytic cells capable of ensuring good resistance to corrosion by the cell chemicals, while maintaining desirable thermal characteristics during service.
Several refractory materials were tested in the Alcan's standard electrolysis bath test. Also, using Alcan's standard procedures, different insulating refractory products were tested for their gain in thermal conductivity after compression. 相似文献
Several refractory materials were tested in the Alcan's standard electrolysis bath test. Also, using Alcan's standard procedures, different insulating refractory products were tested for their gain in thermal conductivity after compression. 相似文献
145.
An accelerated water-streaming test method was used to evaluate several types of façade coatings regarding their behaviour to colonisation by algae and cyanobacteria, by closely reproducing the phenomenon of natural biological soiling. A set of materials with defined physical characteristics was thus investigated vs. the colonisation by algal and cyanobacterial strains isolated from natural façade biofilms. Porosity and roughness of the materials showed to be factors of influence in the establishment of those micro-organisms. 相似文献
146.
This paper presents an original method using a ROM memory, of systematically synthesizing on-line and offline self-testing synchronous sequential machines (automata, sequencers,), for the design of compiled ASIC’S. Choices about state transition graph coding and circuit architecture are related to simplicity, compactness, operating rate and especially to testability. The on-line and off-line testing is based on an error detecting code of a recurrent type: in addition to useful data, the ROM memory contains redundant information which is distributed between two consecutive states. This method guarantees both present state coherence and past transition conformity. On-line testing is based in this type of coding, called distributed redundancy coding. Its fault coverage is given for different classes of hardware failures. Off-line testing, which is exhaustive, uses the distributed redundancy coding technique and consists in scanning all the possible graph transitions in memory address order. 相似文献
147.
An apparatus has been developed for the measurement of thermal conductivity of polymer melts. Based on the transient “line source method,” it is ideally suited to these materials because measurements can be made quickly, before the onset of thermal degradation. Also, little or no sample preparation is required. A number of commercial polymers have been tested, including some glass-fiber filled composites. 相似文献
148.
The corrosion of aluminosilicate refractories by molten aluminum, such as in melting and holding furnaces, generally leads to the formation of an alumina deposit on the refractory. In the presence of alkalies and under a reducing atmosphere the extent of corrosion is increased. This could be related to the transformation of the alumina to sodium aluminate, whose formation kinetics are increased under a reducing atmosphere, promoting the formation of aluminum nitride. In melting and holding furnaces, the alkalies could originate from the presence of a cryothic bath in the metal charge and/or from the refractories. In the latter case, it was shown that aluminum nonwetting refractory castables containing aluminum fluoride as the nonwetting agent could lead to severe corrosion in the above applications if their alkali content is such that it promotes the formation of β-alumina. 相似文献
149.
A section is born: Studies in Automated Reasoning 相似文献
150.
Baker Laura A.; Cesa Ian L.; Gatz Margaret; Mellins Claude 《Canadian Metallurgical Quarterly》1992,7(1):158
Studied genetic and environmental etiologies of positive and negative affect, as measured by the Bradburn Affect Balance Scale, to gain understanding of a 2-factor theory of well-being. It was hypothesized that negative affect would demonstrate significant genetic and environmental variance and positive affect would be explained primarily by environmental influences. Data were combined from 105 pairs of twins (aged 18–72 yrs) and 220 multigenerational families (aged 16–98 yrs). Simultaneous model fitting indicated significant heritable effects for negative affect and a significant effect of common environment for twins. Significant effects for positive affect included common environment (for parents and offspring and for twin pairs) and assortative mating. These results, documenting differential genetic and environmental influences on positive and negative affect, provide further support for their being separate components of well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献