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The relationships between the osculating orbital elements for a family of solutions of the general relativistic Schwarzschild problems are developed. These relationships provide a method for evaluating orbital elements in different Schwarzschild coordinate systems without the necessity of fitting to real data every time the system of coordinates is changed. The objectivity of different coordinate systems is discussed. Considerations of orbital motions favor the standard Schwarzschild metric, but the propagation of light signals is more objective in the metric of Painlevé. Because the orbital motions usually dominate the representation of data, the standard Schwarzschild coordinates are the best objective choice for most applications. 相似文献
113.
In two experiments, saccharin (CS) and lithium chloride (US) were paired in a context consisting of specific visual, auditory, tactual, and olfactory cues. The saccharin aversion was then extinguished in a context free from conditioning-context cues. Later, saccharin preference tests were given in the presence and absence of these cues. The results indicated that the background cues of the conditioning trial controlled the amount of saccharin drunk on extinction trials, and, furthermore, that extinction of the taste aversion was context specific; i.e., groups given extinction trials in a different (from conditioning) context retained their saccharin aversion in the conditioning context only. The results indicate an important role played by the exteroceptive context in taste-aversion conditioning. 相似文献
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Two small-gain theorems and a passivity theorem yielding stability results for general feedback systems are shown to be equivalent. 相似文献
117.
Holder (1988) has raised several objections to our work on the role of exteroceptive contextual stimuli in taste-aversion learning by rats. Our main conclusion from that work is that tongue-tactile stimuli from the drinking spout constitute the likely basis for findings of contextual bottle control over learned taste aversions. Holder suggests that our results are confounded by taste cues from the fluid containers. We refute this suggestion by presenting data from two experiments showing contextual bottle control, even though potential taste cues from the drinking bottles were eliminated. We also point to the fact that some of Holder’s criticisms are based on misreadings of our various reports. 相似文献
118.
This is the second part of a review of research on higher education since World War II. Fart I, published in the previous issue of this Journal, examined how research responded to post‐war reconstruction of the later 1940s and the rising community expectations for education of the 1950s and 1960s. In Part II the themes are equality of opportunity and the end of expansion. By the mid‐1960s many researchers were questioning the representativeness of participation in higher education and the nature of the education process. More recently some of the research questions have been reminiscent of the late 1940s, that is, how can the efficiency of higher education be improved. Whereas expansion and optimism characterised the first thirty post‐war years however, the context is now one of reduced resources and some pessimism. 相似文献
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