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Semiconductors - The parameters of a ferroelectric material without initial polarization are simulated. The ferroelectric material is doped with a shallow-level impurity. One of the contacts is... 相似文献
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SJ McPherson RN Gibson NA Collier TG Speer ND Sherson 《Canadian Metallurgical Quarterly》1998,206(3):665-672
Ancylostoma duodenale is still the dominant hookworm species in the Mediterranean area, India, China and Japan. In the present study, biopsied materials were taken from the small intestine of 30 patients infected only with A. duodenale and 12 cross matched controls. The results showed some pathological changes in severely infected cases. However, normal or insignificant changes were seen in the enzymatic activity of the intestinal mucosa. 相似文献
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Prediction equations for estimating lung volumes have been determined for Caucasians, African-Americans, and Mexican-Americans. These separate equations were determined because of differences in thoracic morphology between people of various racial groups, making it impossible to use one prediction formula to accurately estimate lung volumes for all individuals. One hundred ninety-one adolescent Navajo children (males, n = 110; females, n = 81) between 11 and 18 yr of age volunteered for the study and underwent a series of pulmonary function tests (PFT). New pulmonary function prediction equations for Navajo youth were generated for estimating pulmonary volumes and capacities that more accurately predict expected PFT outcomes than formulas in common use for Caucasian, Mexican-American, or African-American youth. 相似文献
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正事实上,绝大多数攻击者是经由用户及其设备进入企业的。现实情况往往是黑客跟踪一个用户,然后此用户成为帮助黑客到达数据库或用户凭据的一个管道。因此,企业不仅需要端点安全和网络安全,而且还要将不同的安全方案集成起来。安全厂商也应当听从时代的召唤,建设针对新威胁的安全方案,迎接深度安全的新时代。 相似文献
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Sh. M. Berman B. V. Belokon' F. S. Revzina P. D. Pyatikop 《Refractories and Industrial Ceramics》1968,9(7-8):496-502
Conclusions The Panteleimonov Refractories Plant produced a large industrial batch of forsterite roof brick for the lower structure of open-hearth furnaces. Tests carried out at the Donetsk Metallurgical Factory showed that it is desirable to use these forsterite refractories: the life of the regenerator roofs was four campaigns in the main roof with an adequately large residual thickness.Investigations established that the changes in the forsterite brick during service in the roof of regenerators are similar to the changes in bricks during service in other structural elements, but the destruction processes occur much more slowly.Translated from Ogneupory, No. 8, pp. 31–38, August, 1968. 相似文献
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Conclusions The variation of the open porosity of a coating as a function of detonation-deposition process conditions matches that of the quality of the coating as assessed by other parameters. The open porosity of a coating is strongly affected by its surface roughness, and consequently estimates of op may be high. The size of a specimen for open porosity testing should not be greater than 1.2 times the barrel bore. Under optimum conditions the visible porosity of coatings does not exceed 1%.Translated from Poroshkovaya Metallurgiya, No. 7(259), pp. 17–20, July, 1984. 相似文献
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A. Norman J. Berman K. Brehm M. Drake A. Dyer J. Frisby C. Govil C. Hinchey L. Heuer J. Ke S. Kejriwal K. Kuang S. Keyburn S. Ler K. Powers A. Robertson J. Sanghai C. Schulze J. Schieck J. Sussman L. Tan A. Tello R. Wang K. Yan T. Zeinullayev 《Computational Economics》2012,39(3):243-257
Consumers check few sites in online purchases. Previous research and experiments we perform demonstrate that consumers can not calculate the optimal strategy for price search. They use heuristics whose performance is better than random and less than optimal. To investigate online price search performance we survey student online textbook purchases. Students achieve good performance because they start with a good strategy and online market organization of marketplace and meta-search sites. An important factor is that algorithms at sites searched perform calculations that reduce the computational complexity of the search. 相似文献