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Qiwen Wang Xiaoyun Sun Bruce L. Golden Lenore Desilets Edward A. wasil Scott Luco Adam Peck 《Computers & Operations Research》1993,20(8)
A crucial step in manufacturing microcircuits is the wire bonding process in which a very thin gold wire must be formed to connect two surfaces in the microcircuit. The quality of the wire bond can be measured by visual inspection and a pull test—both of which are high-reliability, high-cost approaches to statistical process control. Westinghouse wanted to develop a high-reliability, low-cost quality assurance system. In this paper, we report on a year-long study to construct a neural network model that is capable of predicting the quality of wire bonds. The results of our modeling efforts reveal that neural networks are useful tools for statistical process control problems. 相似文献
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Unilateral spatial neglect declines when participants reach to grip the center of long metal rods compared with when they point to the perceived center, suggesting that visuomotor control systems are less affected by neglect than other representational systems (I. H. Robertson, D. Nico, & B. Hood, 1995). In this study, 16 participants with unilateral left neglect actually picked up rods, and we predicted short-term improvements in neglect because of induced conflict between a phenomenally symmetrical visual world on the one hand and a proprioceptively conveyed rightward-biased world on the other. With participants serving as their own controls, significant short-term improvements in neglect were found on 2 out of 4 neglect tasks after participants experienced proprioceptive feedback discrepant from the judgments they made on the basis of visual information alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Bruce C. Bunker R. James Kirkpatrick Richard K. Brow Gary L. Turner Carolyn Nelson 《Journal of the American Ceramic Society》1991,74(6):1430-1438
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Bruce K. Fink Roy L. McCullough John W. Gillespie 《Polymer Engineering and Science》1992,32(5):357-369
For joining and repair of continuous fiber thermoplastic composites, induction heating has been viewed a strong candidate. Induction heating employs an applied alternating magnetic field, which induces a rotational emf in a grid of conductive carbon fibers, which are then used to carry resulting currents. In continuous carbon fiber crossply composites the available paths for “eddy current” loops are along the network of conductive carbon fibers. For this to occur, an electrical transfer must take place between crossing fibers in adjacent plies. Tests involving variable thicknesses of interply neat film layers have been performed to provide insight into the mechanisms taking place. These tests indicate that the primary mechanism for heating in such laminates is dielectric losses in the polymeric region between fibers in adjacent planes that form the conductive loop. Therefore, heating is not uniform in such composites despite a uniform magnetic flux. Heating patterns were viewed using liquid crystal materials and E-type thermocouples. Several factors leading to nonhomogeneous thermal distributions have been considered, including current density effects, internal emf cancellation, and rotational field effects. Global and local considerations are addressed, a localized model is proposed, and the corresponding theory is developed qualifying the early results. Additional testing has supported the theory. 相似文献
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The effects of age stereotyping on subjects' ratings of interviewee potential were investigated using a simulated auditory interview. Male and female participants (N?=?156) listened to a 12-min interview of a supervisory candidate applying for a temporary position in industry and then rated the interviewee's qualifications for the supervisory position. Participants gave higher overall interview ratings to a younger interviewee even though he had the same qualifications as an older interviewee. Ratings given to the older interviewee, however, were not significantly different from those given to an interviewee whose age was not designated. The findings are discussed in terms of the influence of both positive and negative age stereotypes on ratings of applicant potential. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Alexander A. Kortt J. Bruce Caldwell 《Journal of the science of food and agriculture》1985,36(9):863-870
The acidic and basic lectins of the winged bean were isolated from seed extracts by affinity chromatography on lactose-Sepharose 6B and melibiose Bio-Gel P150, respectively. The lectins isolated from six varieties of Psophocarpus tetragonolobus, collected from different regions of south-east Asia, showed no significant differences in their properties; their subunit Mr and amino acid compositions were the same as those of the acidic and basic lectins isolated by non-affinity methods. On isoelectric focusing the affinity purified acidic lectins showed two major protein components (isolectins) while the affinity purified basic lectins had four protein components. The acidic lectins showed a preference for β-D-galactosides and they agglutinated trypsinised human type A, B and O erythrocytes but not trypsinised rabbit erythrocytes. The basic lectins showed a preference for α-D-galactosides and they agglutinated trypsinised rabbit and human type A and B erythrocytes but not trypsinised human type O erythrocytes. 相似文献
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Bruce J. Poppleton 《Polymer Bulletin》1985,13(5):421-424
Summary The average solid-state molecular structures of end-groups generated through chain termination reactions in the polymerization of methyl methacrylate have been derived from published crystallographic data. Evidence is provided for the reduced stability of the head-head chain-termination configuration and in support of the postulate that it is a preferred site of chain scission. Comparable evidence for the unsaturated end group has not been found. 相似文献