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941.
An upgraded system for controlling pneumatic transportation of glass batch materials produced by the Stromizmeritel' JSC is considered. Comparative analysis of various schemes of control over the process of filling the pneumatic-cell pump with material is provided. 相似文献
942.
L. N. Stepanova V. V. Ivliev E. Yu. Lebedev S. I. Kabanov V. A. Bespalov V. P. Tyrin S. A. Bekher E. V. Boyarkin 《Russian Journal of Nondestructive Testing》2007,43(4):263-269
A testing technique developed for determining the acceptance levels of different inspected zones of a wheel pair is considered. It has been shown that the acceptance levels are individual for different inspected zones and are set on the basis of the statistical data obtained during the tests of wheel pairs containing flaws detected beforehand. A test record sheet containing coordinates of flaws and comments on their hazard is issued during automated acoustic-emission testing of the wheel pairs of a freight-car carriage. 相似文献
943.
944.
945.
B. E. Nikol'skii N. L. Patratii Yu. V. Frolov 《Combustion, Explosion, and Shock Waves》1992,28(1):45-47
Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 1, pp. 51–53, January–February, 1992. 相似文献
946.
The results are presented of experimental examination of the effect of the grain size on the spoliation of copper. Levels of the loading pressure, corresponding to various stages of spollation, were determined for two initial states characterized by a mean grain size of 0.29 and 1.62 mm. The results show that for the material with the smaller grain these levels are approximately 0.2 GPa higher than for the material with the larger grain size.Translated from Problemy Prochnosti, No. 2, pp. 73–75, February, 1996. 相似文献
947.
A method of calculating the response of sensitive elements based on wave delay devices is described using as an example a
gauge for measuring the diameter of holes in metal objects. The efficiency of a sensitive element consisting a cylindrical
helix with a longitudinally conducting shield is demonstrated.
Translated from Izmeritel'naya Tekhnika, No. 9, pp. 46–50, September, 1996. 相似文献
948.
The application of a combination of join and semi-join operations to minimize the amount of data transmission required for distributed query processing is discussed. Specifically, two important concepts that occur with the use of join operations as reducers in query processing, namely, gainful semi-joins and pure joint attributes, are used. Some semi-joint, though not profitable themselves, may benefit the execution of subsequent join operations as reducers. Such a semi-join is termed a gainful semi-join. In addition, join attributes that are not part of the output attributes are referred to as pure join attributes. They exploit the usefulness of gainful semi-joins and use the removability of pure join attributes to reduce the amount of data transmission required for query processing. Heuristic searches are developed to determine a sequence of join and semi-join reducers for query processing. Results indicate the importance of the approach to combining joins and semi-joins for distributed query processing 相似文献
949.
R. Murray C. Bryan H. Yu S. Lycett 《Journal of Materials Science: Materials in Electronics》1996,7(5):341-345
The potential associated with quantum well (QW) structures is usually assumed to be a step function; this implies a compositional abruptness at each interface. But abrupt interfaces do not occur in practice, especially if one of the atoms segregates during growth. This leads to asymmetries in the QW potentials which could radically affect device performance. 相似文献
950.
As a science and as a special activity concerned with measurements, the science of metrology pursues a classical, orthodox
purpose, mainly involving the measurement of physical quantities. The term “measurement” is now applied also to social, economic,
medical, and other disciplines, including cybernetics and problems of management and control.
Translated from Izmeritel'naya Tekhnika, No. 7, pp. 17–20, July, 1996. 相似文献