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21.
1 Introduction A double-walled invertube is difficult to fabricate other than applying inversion process. Such kind of invertube can be used as impact energy absorbing element in transport vehicles, like aircrafts and automobiles. Reddy T Y[1] did the analysis of Internal inversion and calculated the inversion load. Reid[2] et al. examined nosing and internal inversion of cold drawn steel tube by the finite element package ABAQUS. Recently, Rosa P A[3] et al. investigated Internal invers… 相似文献
22.
The effect of drying and atomization conditions on the physical properties of powders for agglomerate-like materials and skin-forming material are studied in this article. A neural model is used for powder bulk and tapped density predictions. 相似文献
23.
热重分析对高分子材料中碳酸钙的定量研究 总被引:1,自引:0,他引:1
碳酸钙是高分子材料中常用的无机填料,在高温时会同二氧化碳而失重。利用热重分析可准确定出高分子材料中碳酸钙的含量,同时还可测出聚合物,挥发物的含量,热重分析法样品用量小,灵敏度高,所需时间短。 相似文献
24.
相电流差突变量选相元件在单回线故障中具有良好的选相性能,但在同杆双回线跨线故障中可能误选相。利用六序故障分量的分析方法,分析了相电流突变量在同杆双回线跨线故障中的幅值和相位特征,给出了其相位比相方程。在此基础上,提出了一种运用测量阻抗和方向元件相结合的综合选相方法,并给出了选相流程图。仿真结果表明,在双回线简单故障和跨线故障时,基于单回线单端电气量的同杆并架双回线综合选相方法具有较理想的选相性能。 相似文献
25.
The mirror effect for word frequency refers to the finding that low-frequency words have higher hit rates and lower false alarm rates than high-frequency words. This result is typically interpreted in terms of conventional signal detection theory (SDT), in which case it indicates that the order of the underlying old item distributions mirrors the order of the new item distributions. However, when viewed in terms of a mixture version of SDT, the order of hits and false alarms does not necessarily imply the same order in the underlying distributions because of possible effects of mixing. A reversal in underlying distributions did not appear for fits of mixture SDT models to data from 4 experiments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
从理论上分析了产生地电流干扰的原因,从而在实践上提出了一些经常被忽略,却是行之有效的方法来减小地电流的干扰,设计出高质量的电路。 相似文献
27.
Magnuson James S.; Tanenhaus Michael K.; Aslin Richard N.; Dahan Delphine 《Canadian Metallurgical Quarterly》2003,132(2):202
The time course of spoken word recognition depends largely on the frequencies of a word and its competitors, or neighbors (similar-sounding words). However, variability in natural lexicons makes systematic analysis of frequency and neighbor similarity difficult. Artificial lexicons were used to achieve precise control over word frequency and phonological similarity. Eye tracking provided time course measures of lexical activation and competition (during spoken instructions to perform visually guided tasks) both during and after word learning, as a function of word frequency, neighbor type, and neighbor frequency. Apparent shifts from holistic to incremental competitor effects were observed in adults and neural network simulations, suggesting such shifts reflect general properties of learning rather than changes in the nature of lexical representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
29.
Reviews the book, Basic Processes in Reading Visual Word Recognition by Derek Besner and Glyn W. Humphreys (see record 1990-99017-000). While there has been an increase in the amount of work on many different aspects of reading, as Besner and Humphreys point out in the overview to their book, the vast majority of the research on the topic of reading in the past twenty years has been concerned with the processes involved in word recognition. For this reason, Besner and Humphreys have attempted to bring together studies on topics which are both relevant to current debates in the field of word recognition, and which are likely to be important for future developments in the field. They have compiled an edited volume consisting of their overview and eight additional chapters. The editors have attempted to span the continuum of processes involved in word recognition and thus have included chapters which cover topics ranging from the visual analysis of words, to those on the influence of semantic factors on word recognition. The authors of these chapters comprise an impressive list of researchers in the field of word recognition, with the majority of chapters being authored by leading researchers on the topic. Given the stature of the authors and the range of topics covered, in theory this volume should provide a very thorough overview of current theory and research on reading. There is no question that each of the chapters is interesting and important in its own right. However, in practice the volume as a whole fell somewhat short of my expectations. The different tacts taken by different authors has resulted in a very uneven coverage of the current debates in the field. Notwithstanding these criticisms, I am sure that the majority of researchers in this field will consider this volume to be an important contribution. The book would provide a very useful addition to graduate courses in cognitive sciences and as a supplemental text for an undergraduate course on the psychology of reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.