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981.
The semi-analytical method of sensitivity analysis (Zienkiewicz and Campbell 1973; Esping 1983; Cheng and Liu 1987) of finite element discretized structures is attractive due to the balance between computational cost and ease of implementation (Cheng and Liu 1987; Haftka and Adelman 1989), but unfortunately the method may exhibit serious inaccuracies when applied in shape optimization of structures modelled by beam, plate, shell and Hermite elements (Cheng and Liu 1987; Haftka and Adelman 1989; Barthelemyet al. 1988; Barthelemy and Haftka 1988; Choi and Twu 1991, Pedersenet al. 1989; Chenget al. 1989).In the present paper, we perform an exact analysis of the error of sensitivity for a simple model problem which has earlier been considered by Barthelemyet al. (1988), Barthelemy and Haftka (1988), Pedersenet al. (1989). The analysis gives a deep insight into the nature of the general inaccuracy problem and enables us to devise methods by which the severe error of the sensitivity can be substantially reduced or removed for the model problem. The results of the paper are illustrated via an example.A method of error elimination for an extended class of semianalytical analysis problems is developed and presented in a companion paper (Olhoff and Rasmussen 1991). 相似文献
982.
983.
Translated from Atomnaya Énergiya, Vol. 66, No. 5, pp. 321–324, May, 1989. 相似文献
984.
Translated from Atomnaya Énergiya, Vol. 66, No. 3, pp. 213–215, March, 1989. 相似文献
985.
986.
A. I. Gorelov A. I. Efanov V. G. Nazaryan V. V. Postnikov A. N. Sviridenkov V. V. Shevchenko 《Atomic Energy》1989,66(2):90-96
Translated from Atomnaya Énergiya, Vol. 66, No. 2, pp. 81–85, February, 1989. 相似文献
987.
Equilibrium constants of pure hydrocarbons in different temperatures and pressures are necessary in most engineering calculations. A general formula has been developed to calculate equilibrium value for a group of hydrocarbons which have the general formula Cn H2n+2 and Cn H2n based on three parameters. This formula is a function of reduced temperature, reduced pressure, and an acentric factor. It is applied within a wide range of temperatures and pressures. As a result this technique is considered to be useful for the predication of K values of pure hydrocarbons depending on its reduced temperature, reduced pressure, and acentric factor. 相似文献
988.
A. Sh. Barekyan A. N. Starilenkov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(1):21-23
A new layout of a fish-protecting facility is proposed.
__________
Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 12, December 2006, pp. 24–26. 相似文献
989.
A new technology for manufacturing gold smalto using a “liquid” gold preparation has been developed. Glasses with different
hues for use as substrates in preparing smalto have been synthesized in the alkali-boro-silicate system. This has made it
possible to expand the range of gold smalto.
__________
Translated from Steklo i Keramika, No. 3, p. 36, March, 2007. 相似文献
990.
H. E. N. Stone 《Journal of Materials Science》1987,22(5):1749-1752
The ratio of the thermal oxidation parameter to the decomposition point (T
p/T
m) is of the order of 0 85 for Y9Co7, indicating a high degree of chemical binding. The persistence of high values of this ratio has been investigated with respect to (a) other compounds in the Y-Co system, (b) replacement of cobalt in Y9Co7 by other d-e!ements, and (c) replacement of yttrium by other rare-earth elements. High ratios are found for (a) Y-Co compounds where Y/Co > 0.5, (b) Y-3d compounds with cobalt and niche! only, end (c) RE-Co compounds generally. However, there are differences in level of the ratio amongst the rare-earth compounds, from which it is inferred that the highest values coincide with full electron shells, that is, without participation of 4f electrons. Additional work is described on an effect of preparation arc-melting current 0n theT
p value for Y9Co7, and on compounds of the same pattern where both components are changed. 相似文献