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991.
In this paper, we suggest a potential use of data compression measures, such as the Entropy, and the Huffman Coding, to assess the effects of noise factors on the reliability of tested systems. In particular, we extend the Taguchi method for robust design by computing the entropy of the percent contribution values of the noise factors. The new measures are computed already at the parameter-design stage, and together with the traditional S/N ratios enable the specification of a robust design. Assuming that (some of) the noise factors should be naturalized, the entropy of a design reflects the potential efforts that will be required in the tolerance-design stage to reach a more reliable system. Using a small example, we illustrate the contribution of the new measure that might alter the designer decision in comparison with the traditional Taguchi method, and ultimately obtain a system with a lower quality loss. Assuming that the percent contribution values can reflect the probability of a noise factor to trigger a disturbance in the system response, a series of probabilistic algorithms can be applied to the robust design problem. We focus on the Huffman coding algorithm, and show how to implement this algorithm such that the designer obtains the minimal expected number of tests in order to find the disturbing noise factor. The entropy measure, in this case, provides the lower bound on the algorithm's performance. 相似文献
992.
Necessary and sufficient conditions are found for continuous and periodic liquid motion in systems containing siphons.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 6, pp. 916–920, June, 1987. 相似文献
993.
994.
995.
The conditions for a rather fast increase in parametric thermomechanical oscillations have been revealed by using numerical solutions of some types of Hill's equation. It is shown that the occurrence of a real parametric resonance is essentially determined by the character of thermal modulations. It is hypothesized that the indicated trends are observed in oscillations of any physical nature.Stavropol State Pedagogical Institute, Stavropol. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, No. 3, pp. 294–298, September, 1992. 相似文献
996.
Barabanenkov Yu.N. Kravtsov Yu.A. Ozrin V.D. Saichev A.I. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1991,79(10):1367-1370
Backscattering enhancement is discussed as a universal wave phenomenon inherent to waves of whatever physical nature: electromagnetic, acoustic, spin, etc. This phenomenon arises due to multichannel wave propagation from a source to a scatterer and back and may be observed in the vicinity of the source because of mutual coherence of waves passing in opposite directions along identical (coherent) channels. Backscattering enhancement may be revealed when the wave field is scattered: by a system of chaotically distributed scatterers or by a system of inhomogeneities; by a body embedded in a turbulent medium; by a single body placed near an interface or within a waveguide (randomness of body position is assumed); by a body of complex form or a system of several scatterers randomly oriented in space; by a rough surface; and by many other physical systems. Possible practical applications of these effects are analyzed 相似文献
997.
The paper describes the synthesis of N-2/4-toluyl methacrylatoethyl carbamates using 2/4-toluyl isocyanate and 2-hydroxyethyl methacrylate. Homopolymerisation and copolymerisation of these novel monomers with methyl methacrylate was carried out using benzoyl peroxide as an initiator and tetrahydrofuran as solvent. Photopolymerisation of N-4-toluyl methacrylatoethyl carbamate could be carried out without the use of photosensitiser. Structural characterisation of copolymers was done using 1H-NMR. Thermal stability of copolymers was evaluated in a nitrogen atmosphere by dynamic thermogravimetry. 相似文献
998.
G. A. Isaak'yan V. Ya. Alekseev A. I. Ivanov N. I. Karmalitsyn A. E. Kochin T. E. Sazonova S. V. Sepman I. F. Uchevatkin V. I. Fominykh 《Atomic Energy》1992,73(5):903-907
Mendeleev All-Union Metrology Research Institute. Translated from Atomnaya Énergiya, Vol. 73, No. 5, pp. 393–397, November 1992. 相似文献
999.
I. R. Tatur D. A. Yakovlev I. A. Timokhin L. R. Berezovskii G. B. Prigul'skii V. A. Lazarev V. N. Sergeev 《Chemical and Petroleum Engineering》1992,28(10):623-627
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 29–31, October, 1992. 相似文献
1000.