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排序方式: 共有206条查询结果,搜索用时 62 毫秒
91.
Suresh BR Fundakowski RA Levitt TS Overland JE 《IEEE transactions on pattern analysis and machine intelligence》1983,(6):563-572
This paper describes an inspection system designed to automatically detect and classify surface imperfections occurring on continuously cast hot steel slabs in a steel mill. The need to perform inspection at real-time throughput rates of 546 Kpixels/s using off-the-shelf components has led to the development of a unique architecture and algorithm set. The segmentation operations are done in a high-speed array processor front end. The imperfection classification is done in a mini-computer which uses statistical as well as syntactic/semantic classification techniques. The inspection system is currently undergoing evaluation in a steel mill. 相似文献
92.
"The purpose of this study was to investigate the interrelationships among ethnocentrism-authoritarianism in children, the child's willingness to be punitive, and the punitiveness of the parent as the child sees it. Three hypotheses postulating positive correlations among the three variables were set up… . It is concluded that the three hypotheses of the study are supported by the data, and that this evidence is in accord with, and reflects favorably upon, the theory of the origin of ethnocentrism-authoritarianism proposed by Frenkel-Brunswik and her associates." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
P Levitt JA Harvey E Friedman K Simansky EH Murphy 《Canadian Metallurgical Quarterly》1997,20(6):269-274
In the current healthcare environment, all healthcare providers are challenged to provide quality patient care in an efficient, cost-effective manner. Managed care organizations and third-party payors actively collect data related to cost, length of stay, resource use, and patient outcomes for use in affiliating and contracting with healthcare facilities and providers. The authors, in this article, outline one organization's evolution from a "utilization review"-based discharge planning process to a proactive "utilization management" approach to care coordination. 相似文献
94.
Zhiyu Wang Si Qin Shayan Seyedin Jizhen Zhang Jiangting Wang Ariana Levitt Na Li Carter Haines Raquel Ovalle‐Robles Weiwei Lei Yury Gogotsi Ray H. Baughman Joselito M. Razal 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(37)
Yarn‐shaped supercapacitors (YSCs) once integrated into fabrics provide promising energy storage solutions to the increasing demand of wearable and portable electronics. In such device format, however, it is a challenge to achieve outstanding electrochemical performance without compromising flexibility. Here, MXene‐based YSCs that exhibit both flexibility and superior energy storage performance by employing a biscrolling approach to create flexible yarns from highly delaminated and pseudocapacitive MXene sheets that are trapped within helical yarn corridors are reported. With specific capacitance and energy and power densities values exceeding those reported for any YSCs, this work illustrates that biscrolled MXene yarns can potentially provide the conformal energy solution for powering electronics beyond just the form factor of flexible YSCs. 相似文献
95.
96.
With recent developments in the field of smart textiles, researchers have been working toward fabricating architectures of nanofibers, known as nanoyarns, which mimic the geometry of a conventional yarn. In doing so, one can leverage the unique properties of nanoscale fibers, including high surface‐to‐volume ratio and tunable porosity, for the development of smart garments. In the last 5 years, researchers have produced nanoyarns from a limited number of polymers, including polyacrylonitrile (PAN) and poly(vinylidene fluoride) and its co‐polymers. However, to our knowledge, there has been little research on the solution properties and electrospinning parameters needed to fabricate these higher‐order architectures from nonwoven mats. In this work, a modified electrospinning setup, enclosed in a humidity‐controlled chamber, was developed to fabricate nanoyarns for integration into knitted textiles. We fabricated nanofibers and nanoyarns from PAN/DMF solutions and conducted a systematic study to analyze the effect of solution conductivity, viscosity, and electrospinning parameters (applied voltage, collector distance, and humidity) on fiber and yarn fabrication and morphology. Polymer concentration had a significant effect on fibrous cone and yarn fabrication. Low polymer concentrations resulted in poor cone formation, whereas high concentration resulted in dense cones that were difficult to draw into nanoyarns. Overall, the matrix of electrospinning parameters that resulted in the formation of homogenous nanofiber mats was larger than that of nanoyarn formation. Nanoyarn formation required higher polymer concentration and/or applied voltage than nonwoven mat formation. The influence of these parameters on nanoyarn formation and fiber diameter can be used to expand the library of spinnable nanoyarns and optimize their properties for specific applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46404. 相似文献
97.
Earl Allison; Albarracín Dolores; Durantini Marta R.; Gunnoe Joann B.; Leeper Josh; Levitt Justin H. 《Canadian Metallurgical Quarterly》2009,77(4):668
HIV-prevention intervention effectiveness depends on understanding whether clients with highest need for HIV-prevention counseling accept it. With this objective, a field study with a high-risk community sample from the southeastern United States (N = 350) investigated whether initial knowledge about HIV, motivation to use condoms, condom-use-relevant behavioral skills, and prior condom use correlate with subsequent acceptance of an HIV-prevention counseling session. Ironically, participants with high (vs. low) motivation to use condoms, high (vs. low) condom-use-relevant behavioral skills, and high (vs. low) prior condom use were more likely to accept the HIV-prevention counseling. Moreover, the influence of motivation to use condoms, condom-use-relevant behavioral skills, and prior condom use on acceptance of the counseling was mediated by expectations that the counseling session would be useful. Methods to reduce barriers to recruitment of clients for counseling programs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Many studies have found that collaborative research is, in general, more highly cited than non-collaborative research. This
paper describes an investigation into the extent to which the association between high citation and collaboration for Economics
articles published in 2000 varies from region to region and depends on the choice of indicator of citation level. Using data
from the Social Science Citation Index (SSCI) for 18 countries, 17 American states and four indicators of citation level the
citation levels of the collaborative articles are compared with the citation levels of the non-collaborative articles. The
main findings are that: (a) for every country and every indicator the mean citation level of the collaborative articles was
at least as high as that for the non-collaborative articles, but for five US states and for at least one other indicator the
citation level of collaborative articles was lower than that of non-collaborative articles, and (b) the extent to which collaborative
articles were more highly cited varied considerably from country to country, from state to state, and from indicator to indicator.
This indicates the importance of using multiple indicators when investigating citation advantage since the choice of indicator
can change the results. 相似文献
99.
100.
F Mann V Zhukareva A Pimenta P Levitt J Bolz 《Canadian Metallurgical Quarterly》1998,18(22):9409-9419
Membrane-associated signals expressed in restricted domains of the developing cerebral cortex may mediate axon target recognition during the establishment of thalamocortical projections, which form in a highly precise manner during development. To test this hypothesis, we first analyzed the outgrowth of thalamic explants from limbic and nonlimbic nuclei on membrane substrates prepared from limbic cortex and neocortex. The results show that different thalamic fiber populations are able to discriminate between membrane substrates prepared from target and nontarget cortical regions. A candidate molecule that could mediate selective choice in the thalamocortical system is the limbic system-associated membrane protein (LAMP), which is an early marker of cortical and subcortical limbic regions (Pimenta et al.,1995) that can promote outgrowth of limbic axons. Limbic thalamic and cortical axons showed preferences for recombinant LAMP (rLAMP) in a stripe assay. Incubation of cortical membranes with an antibody against LAMP prevented the ability of limbic thalamic fibers to distinguish between membranes from limbic cortex and neocortex. Strikingly, nonlimbic thalamic fibers also responded to LAMP, but in contrast to limbic thalamic fibers, rLAMP inhibited branch formation and acted as a repulsive axonal guidance signal for nonlimbic thalamic axons. The present studies indicate that LAMP fulfills a role as a selective guidance cue in the developing thalamocortical system. 相似文献