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141.
The energetic driving force and resistance for shearing and cracking in metallic glasses (MGs) are quantitatively evaluated. A universal thermodynamic criterion is proposed for better understanding the intrinsic correlations between fracture toughness and Poisson’s ratio, the competitions between various deformation modes and the ductile-to-brittle transition in MGs and other materials. A new cooperation parameter δ is also introduced to depict quantitatively the relative propensity of shearing versus cracking. This work could provide insights into the long-standing issues of deformation mechanisms of glassy materials, and be helpful in searching for ductile and tough MGs. 相似文献
142.
K. Yan 《Philosophical Magazine Letters》2013,93(1):51-58
The rapid increase of surface area-volume ratio (SVR) with shrinking structure size has a great impact on surface-related intrinsic dissipation, which usually leads to low quality factors for the devices composed of nanoelectromechanical systems. In the present study, the flexural oscillations of nanocantilevers with varying thicknesses and lengths were simulated using the molecular dynamics method, in which the surface effects on the energy dissipation was evaluated when SVR was increased to extremely large values (between 0.4 and 2.0 nm?1). And, it is also interesting to note that the prediction of the size-dependent Young's modulus by means of resonant frequency of the underdamped oscillation showed good agreement with previous findings. 相似文献
143.
Laura M. Castelli 《British Journal for the History of Philosophy》2013,21(5):941-943
ABSTRACTThe example of the Spanish poet’s amnesia, mentioned by Spinoza in the scholium of proposition 39 of part IV of the Ethics in order to elucidate his conception of death, has given rise to many controversies in the scholarly interpretations, which in most cases maintain that the poet dies and that Spinoza himself thought this way. However, the matter is more complex than it at first appears and in this article I take a different path by reconstructing this scholium anew and providing an alternative interpretation. The comparison with selected passages of part V highlights the presence of a bi-conditional between the ratio of motion and rest that a body possesses, and its aptitude to be affected and affect in many more ways. In particular, the latter allows us to acknowledge the continuity of the poet’s individuality, expressed in his mind–body union grounded by the parallelism theory. As a result, the poet case has a crucial explanatory role for Spinoza’s theory of the eternity of the human mind and if one misunderstands the former, the latter is also misconceived. 相似文献
144.
145.
The fears of 133 boys and girls aged 7 to 19, classified as educable mentally retarded (EMR), trainable mentally retarded (TMR), and specific learning disabled (SLD), were ascertained through self-report data and compared with those of 106 normal children aged 6 to 12. Similar developmental trends were found in all groups, with younger children reporting more unrealistic fears than older children. When mental age was calculated for the EMR and TMR children, their developmental trends closely approximated those of the normal children. In general, exceptional children were found to have a much wider range and a greater number of fears than normal children. Most fears were found to be realistic, learned, and dependent upon the child's intellectual and maturational level. 相似文献
146.
The Allais common ratio effect is one of the most robust violations of rational decision making under risk. In this paper, we conduct a novel test of the common ratio effect in which we elicit preferences for the common ratio choice alternatives in choice, pricing, and happiness rating tasks. We find large shifts in preference patterns across tasks, both within and between subjects. In particular, we find that both the consistency and distribution of responses differ systematically across tasks, with modal choices replicating the Allais preference pattern, modal happiness ratings exhibiting consistent risk aversion, and modal prices maximizing expected value. We discuss the predictions of various cognitive explanations of the common ratio effect in the context of our experiment. We find that a dual process framework provides the most complete account of our results. Surprisingly, we also find that although the Allais pattern was the modal behavior in the choice task, none of the 158 respondents in our experiment exhibited the Allais pattern simultaneously in choice, happiness, and pricing tasks. Our results constitute a new paradox for the leading theories of choice under risk. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
147.
Research examining both the organizing and activating effects of testosterone in one-shot bargaining contexts has been vexed by inconsistencies. Some research finds that high-testosterone men are more likely to reject unfair offers in an ultimatum game and exogenous administration of testosterone to men leads to less generous offers. In contrast, other research finds that higher prenatal exposure to testosterone predicts more generous dictator game offers and administering testosterone to women leads to more generous ultimatum game offers. The current research seeks to resolve these inconsistencies by examining how the organizing effects of testosterone affect bargaining behavior. Because testosterone is associated with status seeking and concerns with social reputation, we hypothesized that testosterone would predict aggressive bargaining but only after provocation. Two studies found that prenatal testosterone exposure, as measured by 2D:4D ratio, led to aggressive responses for both males and females, but only after they received unfair offers. Furthermore, perceptions of fairness violations moderated but did not mediate the effect of testosterone on retributional responding. These results suggest that the organizing effects of testosterone have consistent effects on bargaining behavior for both males and females but its predictive ability requires some form of provocation to emerge. 相似文献
148.
Frank W. Samuelson 《Journal of mathematical psychology》2011,55(3):223-228
Signal detection experiments with human observers frequently generate ordinal data which are evaluated using receiver operating characteristic (ROC) methods. These methods may include regressing a continuous two-distribution model to the data set. Because we assume that human observers will not systematically select observations absent the signal, this model should have a monotonic likelihood ratio between the distributions. This paper gives a general method for constructing pairs of distributions that have monotonic likelihood ratios and a possibly large number flexible parameters. It suggests two specific simple parametric forms of monotonic likelihood ratios, constructs new distributions with those likelihood ratios using other standard distributions, and performs ordinal regression with those new distributions to model some example data from the literature. 相似文献
149.
Williams DC Saunders KJ Perone M 《Journal of the experimental analysis of behavior》2011,95(2):203-220
We conducted three experiments to reproduce and extend Perone and Courtney's (1992) study of pausing at the beginning of fixed-ratio schedules. In a multiple schedule with unequal amounts of food across two components, they found that pigeons paused longest in the component associated with the smaller amount of food (the lean component), but only when it was preceded by the rich component. In our studies, adults with mild intellectual disabilities responded on a touch-sensitive computer monitor to produce money. In Experiment 1, the multiple-schedule components differed in both response requirement and reinforcer magnitude (i.e., the rich component required fewer responses and produced more money than the lean component). Effects shown with pigeons were reproduced in all 7 participants. In Experiment 2, we removed the stimuli that signaled the two schedule components, and participants' extended pausing was eliminated. In Experiment 3, to assess sensitivity to reinforcer magnitude versus fixed-ratio size, we presented conditions with equal ratio sizes but disparate magnitudes and conditions with equal magnitudes but disparate ratio sizes. Sensitivity to these manipulations was idiosyncratic. The present experiments obtained schedule control in verbally competent human participants and, despite procedural differences, we reproduced findings with animal participants. We showed that pausing is jointly determined by past conditions of reinforcement and stimuli correlated with upcoming conditions. 相似文献
150.
Challies DM Hunt M Garry M Harper DN 《Journal of the experimental analysis of behavior》2011,96(3):343-362
The misinformation effect is a term used in the cognitive psychological literature to describe both experimental and real-world instances in which misleading information is incorporated into an account of an historical event. In many real-world situations, it is not possible to identify a distinct source of misinformation, and it appears that the witness may have inferred a false memory by integrating information from a variety of sources. In a stimulus equivalence task, a small number of trained relations between some members of a class of arbitrary stimuli result in a large number of untrained, or emergent relations, between all members of the class. Misleading information was introduced into a simple memory task between a learning phase and a recognition test by means of a match-to-sample stimulus equivalence task that included both stimuli from the original learning task and novel stimuli. At the recognition test, participants given equivalence training were more likely to misidentify patterns than those who were not given such training. The misinformation effect was distinct from the effects of prior stimulus exposure, or partial stimulus control. In summary, stimulus equivalence processes may underlie some real-world manifestations of the misinformation effect. 相似文献