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891.
Abstract

Gives an overview and analysis of the role of the Pacific region in the world economy stressing the ongoing shift of growth potential and purchasing power. Japan's surplus is discussed as a tool to stimulate economic growth in the world. Trends in Pacific cooperation are given.  相似文献   
892.
关于启动工作记忆负荷的强度与过滤分心刺激这两种认知资源的关系一直存在争论;并且对ADHD儿童来说,新异的分心刺激是提高了唤醒水平,还是干扰了任务进程也一直存在争论。本研究选取了ADHD儿童32名,正常儿童35名。采用视听跨通道oddball任务,通过操作视觉任务工作记忆负荷的高低,以及分心刺激与目标刺激之间的时间间隔,探讨不同工作记忆负荷对 ADHD 儿童过滤新异分心刺激能力的影响。结果发现:(1)在低工作记忆负荷条件下,分心刺激对两组儿童都起到了唤醒作用;在高工作记忆负荷条件下,分心刺激影响了两组儿童对任务本身的加工过程,使其判断的精确性下降。但是 ADHD 儿童受到的影响更大,表明其过滤分心刺激的能力落后。(2)当分心刺激与目标刺激同时出现时, ADHD儿童受到的干扰最大;但随着二者时间间隔的延长,并没有出现间隔越长干扰效应越小的趋势。在本研究条件下,得出以下结论:(1)两组儿童对跨通道新异分心刺激的过滤受到目标任务的工作记忆负荷强度的影响。(2)适度延长分心刺激与目标刺激之间的时间间隔可能会帮助ADHD的注意回归。  相似文献   
893.

Cracks in a 2% tensile strained In0.72Ga0.28P film grown on an InP substrate by molecular-beam epitaxy have been studied by cross-section transmission electron microscopy and scanning probe microscopy. A dislocation analogue (i.e. replacing the crack by an array of equivalent infinitesimal edge dislocations) is employed to account for the ratio of the crack-opening displacement to the normal surface displacement associated with the crack.  相似文献   
894.
With decreasing sample dimension, the compressive plastic strain of a Zr-based metallic glass increases from near zero to as high as 80% without failure. This indicates that macroscopically brittle or ductile deformation behaviour can occur in chemically and structurally identical metallic glass. A concept of critical shear offset is proposed to explain the strong size effect on the enhanced plasticity of metallic glass by taking the shear fracture energy density into account. This finding provides new understanding on the principle that for metallic glass ‘smaller is more ductile’, even on the macroscopic scale.  相似文献   
895.
It is shown that the compressive plasticity of a metallic glass, namely Zr52.5Ni14.6Al10Cu17.9Ti5, can be improved by the introduction of two symmetrical notches. The enhanced plasticity may be ascribed to a blocking effect of the propagation of shear bands caused by large stress gradients around the notches. In contrast to ceramic specimens with similar notches, the plasticity enhancement of metallic glass induced by notches can provide a new approach to understanding its unique mechanism of deformation.  相似文献   
896.

The phase transitions of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass have been investigated under high pressures and at room temperature. Direct resistance measurements in a diamond anvil cell provide evidence of a reversible transition between amorphous and crystalline phases; crystallization events occurred at 24 and 26.2 GPa on uploading, and crystalline-to-amorphous phase transitions were observed at 16 and 10.6 GPa on downloading. The phase transitions were confirmed by transmission electron microscopy observations.  相似文献   
897.
Work function (WF) can be measured using the Kelvin probe (KP) technique to characterize surface behavior of micro/nanostructures grown on substrates such as metals or semiconductors. However, for such micro/nanostructures, substrates with different WF can strongly affect the measurements if they are exposed directly to face the Kevin probe tip. In this article, a model is proposed to investigate the WF of sparse ZnO nanorods grown on an Si substrate. It is demonstrated that theoretical results from the model are consistent with experimental observations performed using a KP system.  相似文献   
898.

The alpha -> beta polytypic transformation in SiC was observed during ball milling at room temperature. Microstructural evolution was characterized on an atomic scale by high-resolution electron microscopy (HREM). HREM observations showed that partial dislocations play an important role in the transformation under the complicated conditions during ball milling.  相似文献   
899.
The shortage of organs for transplantation in Japan has alerted health professionals to the low organ donation rate among Japanese people. The unique cultural view of death and altruism has been suggested leading to their low intent to donate cadaveric organs. A cross‐sectional survey was conducted in Japan to investigate the interplay of death anxiety, altruism, and self‐efficacy in influencing Japanese college students' intention to sign donor cards, in order to mobilise this large potential source of organ donors in the future. Six hundred and seven Japanese non‐donor card signers voluntarily completed a self‐administered questionnaire. The results of mediation and moderated mediation analyses with bootstrap approach suggest that death anxiety indirectly hinders Japanese people's intention to become a donor card signer through lowering of self‐efficacy, while altruism intensifies the positive impact of self‐efficacy on signing intention. These findings provide useful insights for organ procurement organisations seeking behavioural change not only in Japan but also in multi‐ethnic societies with a substantial Japanese population.  相似文献   
900.
The study examined the effects of gender and item content of domain‐general and domain‐specific creative‐thinking tests on four subscale scores of creative‐thinking (fluency, flexibility, originality, and elaboration). Chinese tenth‐grade students (234 males and 244 females) participated in the study. Domain‐general creative thinking was measured by using two domain‐independent items—box and newspaper. Domain‐specific creative thinking was measured in the domain of history by two history‐specific items—school uniform and health food—that were part of lessons in modern Chinese history. Domain‐general creative‐thinking scores were not different across gender in any of the four subscales. In domain‐specific creative thinking, female students produced more responses (fluency) and more categories of ideas (flexibility), and more detailed answers (elaboration) on both items than did males. Gender difference was not found in originality. Item effects were significant in both general and specific creative‐thinking scores, with higher fluency, flexibility, and elaboration for the newspaper than the box item, and higher fluency, flexibility, originality, and elaboration for the school uniform than the health food item. The findings on both gender and item effects support the contention that personal interest and life experience influence the generation of creative solutions. The finding that gender did not differ in domain‐general creative‐thinking was expected, as the two general items (box and newspaper) are experienced similarly by both genders. As most of the creative‐thinking tests are influenced by individuals' experience beyond creative‐thinking ability, judicial evaluation and use of creative‐thinking scores are underscored.  相似文献   
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