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641.
Helium generated in materials by the nuclear reaction (n,?α) is generally considered to be harmful. It is well-known that helium prompts not only the nucleation of interstitial-type dislocation loops, but also the nucleation of voids in metals and alloys irradiated with high-energy particles, which degrades their mechanical properties. In this study, however, we find that helium trapped by dislocations in Ni increases both the ultimate tensile strength and total elongation.  相似文献   
642.

Some new observations concerning the spatial-temporal dynamics of selfaffine interfaces formed in paper-wetting experiments are reported. We find that the motion of the wet front in a porous medium has a stepwise nature. The height of the wetted area, as a function of time, displays a Devil's-staircase-like behaviour with scaling exponent delta, whereas the front width oscillates erratically with time. These erratic oscillations possess a statistical self-affine invariance in time with the scaling exponent chi, which is found to be equal to the growth exponent beta. We also note that the values of chi, beta and delta, as well as the interface roughness (Hurst) exponent H vary from one experiment to another in wide ranges, and that their distributions obey a normal distribution. The mean values of all the exponents are dependent on the paper structure, but not on the environmental conditions. Furthermore, we find that the mean value of beta depends on the interface front orientation with respect to the fibre direction in the paper, whereas the mean values of H and delta do not depend on it.  相似文献   
643.
In this essay, I investigate the origins of Chinese migrant transnationalism and its personal and social consequences. I propose a theoretical perspective that turns on a synthesis that I shall call “cultural functionalism,” a synthesis that attempts to reconcile functionalism and postmodernism. My argument is that Chinese transmigrants overcome (post)modern alienation through a two-way approach: first, a strong participation in and full commitment to community development and connectivity within the Chinese diaspora; and, second, a religio-cultural renaissance—both being conceived of as constituting a putative “cultural contract” and “social capital” nexus.  相似文献   
644.
In response to the rapidly increasing application and abuse of psychological tests in China, the Psychometrics Division of the Chinese Psychological Society published the 2008 revisions of the Chinese Code of Ethical Use of Psychological Tests. We investigated the implementation status of the code 2½ years after its promulgation. Sample included 284 psychological professionals and psychology graduate students. The average accuracy rate for the appropriate use of psychological tests was 67.1% (range = 25.5–97.5%), with 10 items having accuracy rates below 45%. Participants remained uncertain about the clients' rights to information about the purpose, psychometric properties, and scores of the tests. The most frequent violations involved “using psychological tests without psychometric information for entertainment purposes” and “using SCL-90 to measure mental health of normal people.”  相似文献   
645.
We investigated when consumers' judgments about a product reflect information about its product source (the person who creates the product). Three experiments manipulated congruence between the source's gender and the gender-typing of the source's product. When congruent with expectations (a male conductor played male-typed music), pre-trial source information had the same effect on post-trial product judgments as when source information was absent. Incongruence (a female conductor played male-typed music) distorted product attribute judgments when the source's competence was questioned. Her music was judged to be more delicate, less powerful and worse quality than his. This process of product experience being assimilated into incompetence stereotypes required minimal cognitive resources. When the incongruent source was undoubtedly competent, the amount of experiential evidence about an attribute influenced distortion. Consumers judged powerful music as powerful regardless of conductor gender, but, lacking much evidence about its delicacy, judged hers as more delicate than his. The selective effect of source gender information reflects consumers' cognitively effortful hypothesis testing of beliefs that gender expresses itself in a person's output against experiential evidence.  相似文献   
646.
When target accuracy is defined as the probability that an individual will respond to an accuracy task within a fixed distance around the target, then the composite error measures, E and AE, are shown to be fairly strong indicators of target accuracy in a relative sense. When AE and E are compared, AE is shown to be an even stronger accuracy indicator than E for most reasonable accuracy requirements. This, plus the fact that AE has certain desirable properties in ANOVA procedures, suggests that AE is a good, composite measure of target accuracy and should be analyzed first to determine if target accuracy differences exist. Subsequent analyses of bias and/or variability are then recommended.  相似文献   
647.
Previous research has suggested that irrational thinking may play a central role in the maintenance of behavior in slot machine gambling (M. B. Walker, 1992b). The present study is an evaluation of the validity and predictors of irrational thinking in a sample of regular gamblers (N = 20) drawn from the general community. The results were generally consistent with earlier findings; 75% of gambling-related cognitions were found to be irrational. Irrationality was unrelated to the amount of money lost or won during sessions but was positively related to risk taking. The most common irrational cognitions included false beliefs concerning the extent to which outcomes could be controlled or predicted and the attribution of human qualities (personification) to gambling devices. Gender comparisons showed that women were more likely than men to personify the machines. The validity of the speaking-aloud approach and suggestions for future research are discussed.  相似文献   
648.
Null hypothesis significance testing uses the seemingly arbitrary probability of .05 as a means of objectively determining whether a tested effect is reliable. Within recent psychological articles, research has found an overrepresentation of p values around this cut-off. The present study examined whether this overrepresentation is a product of recent pressure to publish or whether it has existed throughout psychological research. Articles published in 1965 and 2005 from two prominent psychology journals were examined. Like previous research, the frequency of p values at and just below .05 was greater than expected compared to p frequencies in other ranges. While this overrepresentation was found for values published in both 1965 and 2005, it was much greater in 2005. Additionally, p values close to but over .05 were more likely to be rounded down to, or incorrectly reported as, significant in 2005 than in 1965. Modern statistical software and an increased pressure to publish may explain this pattern. The problem may be alleviated by reduced reliance on p values and increased reporting of confidence intervals and effect sizes.  相似文献   
649.
A modern test that takes advantage of the opportunities provided by advancements in computer technology is the multimedia test. The purpose of this study was to investigate the criterion-related validity of a specific open-ended multimedia test, namely a webcam test, by means of a concurrent validity study. In a webcam test a number of work-related situations are presented and participants have to respond as if these were real work situations. The responses are recorded with a webcam. The aim of the webcam test which we investigated is to measure the effectiveness of social work behaviour. This first field study on a webcam test was conducted in an employment agency in The Netherlands. The sample consisted of 188 consultants who participated in a certification process. For the webcam test, good interrater reliabilities and internal consistencies were found. The results showed the webcam test to be significantly correlated with job placement success. The webcam test scores were also found to be related to job knowledge. Hierarchical regression analysis demonstrated that the webcam test has incremental validity up to and beyond job knowledge in predicting job placement success. The webcam test, therefore, seems a promising type of instrument for personnel selection.  相似文献   
650.
We discuss some core issues in the field of change management. We use these topics to identify some mindsets that dominate the practice of change management, and argue that these should be replaced by some alternatives. The alternatives are drawn largely from operations management and sociotechnical thinking. We characterize existing approaches as partial, and speculate that this may be one of the reasons why so many change initiatives are ineffective at meeting their goals. We identify some of the reasons why existing mindsets are sustained. We also point to some ways forward, focusing on changes in the mindsets and language we use. We speculate that these would improve the effectiveness of change initiatives.  相似文献   
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