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91.
R Herruzo-Cabrera L Malo-González ME Calle Purón MJ Vizcaíno-Alcaide J Del Rey-Calero 《Canadian Metallurgical Quarterly》1993,9(4):442-446
A cross-sectional study was performed to obtain risk factors for hepatitis B disease, HBsAg carriers and immunised personnel, among 2470 workers in a general hospital in Madrid, Spain. The data obtained were analyzed with multiple logistic regression to obtain beta coefficients for variables. The results of the analysis show that being a nurse or being regularly exposed to blood are the most important risk factors for hepatitis B acquisition. The length of time working at the same job activity was also a risk factor. The resulting beta coefficients allow the construction for a hepatitis non-immunised, HBsAg carrier and immunised HBV status, which can select subjects for a hepatitis B vaccination program. 相似文献
92.
93.
Metal Science and Heat Treatment - 相似文献
94.
95.
96.
V. I. Kusov A. K. Gruznov V. I. Kulichkov N. P. Kusova A. V. Dyubchenko 《Metallurgist》1989,33(11):224-225
Institute of Ferrous Metallurgy. Novolipetsk Metallurgical Combine. Translated from Metallurg, No. 11, pp. 32–33, November, 1989. 相似文献
97.
98.
Yu. I. Berdyshev 《Journal of Computer and Systems Sciences International》2006,45(4):526-531
An algorithm for construction of the reachability domain by the given time instant ? for a nonlinear third order system under the condition of preliminary approach to a predefined point is proposed. All possible cases of location of this point in the motion plane of the system for different values of the time instant ? are studied. 相似文献
99.
This paper considers the principles of algorithmic and software implementation of the software system NADRA 3D designed to
analyze processes in three-dimensional multicomponent soil media. The principles of operation of NADRA 3D are described.
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Translated from Kibernetika i Sistemnyi Analiz, No. 6, pp. 157–174, November–December 2006. 相似文献
100.
PHYSICS-BASED SIMULATION OF HIGH SPEED MACHINING 总被引:3,自引:0,他引:3
Eu-Gene Ng Tahany I. El-Wardany Mihaela Dumitrescu Mohamed A. Elbestawi 《Machining Science and Technology》2002,6(3):301-329
Computer simulation of high speed machining processes can provide a unique insight and reduce the number of design iterations required to advance and optimize the process. Predictive modeling of high speed machining of exotic materials has been hindered by the nonlinear behavior of this type of materials at extremely high strain, strain rate, and temperatures. This paper presents a physics-based modeling technology that includes the change in the material constitutive equation and the friction characterization at cutting speeds up to 400 m min-1. The dependence of the accuracy of the predicted parameters, such as the chip formation on cutting forces, chip/tool/workpiece interface temperature, stress and strain distributions are also discussed. The fundamentals of metal cutting were utilized to understand the effect of parameter changes in regimes that are outside current empirical knowledge databases. 相似文献