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1.
The GeO2–NiO system is studied in the stability range of Ni2GeO4 by temperature-dependent resistivity measurements, in combination with x-ray diffraction, differential thermal analysis, and thermogravimetry. The resistivity of the starting mixtures and heat-treated samples is measured in the composition range 55–90 mol % NiO. The effect of air humidity on the resistivity of the samples is examined.  相似文献   
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A physical criterion is proposed for a change in the equilibrium shape of elastically strained germanium nanoclusters growing on a silicon substrate under the conditions of molecular beam expitaxy. The critical size of pyramidal Ge clusters is estimated and compared to the available experimental data.  相似文献   
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It is shown by way of simple examples that the gap metric may be inappropriate for quantifying the uncertainty for lightly damped systems, e.g. flexible structures such as spacecraft and aircraft. Two plants having otherwise identical transfer functions, except that their zeros on the imaginary axis are located slightly apart due to perturbations, are usually considered very close, i.e. their closed-loop characteristics under most stabilizing feedbacks are very similar. However, it is demonstrated that when the gap is used to quantify the plant perturbations, the computed gap may be large. Consequently, the stability of the perturbed plant with a stabilizing controller designed for the nominal plant cannot be guaranteed via the existing stability theorems using the gap metric  相似文献   
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The closed-loop singular values of an LQ regulator transfer function are proved to be no greater than the singular values of the open-loop transfer function and, in the case of output-weighted cost function, to be no greater than the output-weighting parameter  相似文献   
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Results are presented from predictions of the quality indices of metal products used in critical applications. The predictions are obtained for combinations of technological factors that are not used in the actual production process. The reliability of the predictions is confirmed by the fact that the index values obtained with the use of regression models agree with the values obtained using corresponding genetic algorithms. The advantages of the methodology described in the article are demonstrated using the example of analysis of the multi-stage cold rolling of tubes made of zirconium alloys. The introduction of procedures for making technological predictions will help make production processes more efficient and, thus, more competitive. __________ Translated from Metallurg, No. 2, pp. 31–36, February, 2007.  相似文献   
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Conclusions Despite the accumulated evidence, many of the investigators as of quite recently have failed to understand that behavioral strategy or decision rules can be inherited and evolve and that they are subject to certain constraints that cannot be surmounted other than by natural selection. For example, in [9, p. 422] we read: The evolutionary pressure cannot act upon the relative contents of social interactions favoring certain individuals over others. The present study shows that the following scheme of conflict, which favors those individuals that conform to it with a better accuracy, can be evolutionary stable. On the basis of the information they receive, the partners estimate the role situation and the equilibrium pair of elementary strategies and use their strategies. If the role situations of the partners are coordinated, the partners cooperate in reducing the conflict and define its result according to AIS. If AIS are not coordinated, they cooperate in reducing the conflict if its expected loss for each is greater than the expected payoff; they escalate the against those that have a lesser set of elementary strategies but also against those that have a less accurate mechanism of AIS recognition. A poor accuracy of recognition mechanism would replace a strictly equilibrium ESS with a mixed strategy.From the point of view of behavioral control, the multilevel conflict model shows that generally for controlling the choices at a certain level actions of an equally high level are necessary. It is impossible, for example, to accomplish certain economic choices by using only informational actions.Translated from Kibernetika, No. 1, pp. 90–98, January–February, 1988.  相似文献   
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Conclusions A method has been developed for production of standard periclase-chromite concrete parts for the linings of high temperature ladles for teeming steel and ferroalloys. The parts have high strength and low porosity and are practically shrinkage-free.The life of periclase-chromite concrete parts in the steel teeming ladles of Chelyabinsk Metallurgical Plant is about four times greater than that of fireclay parts, in Red October Plant practically the same as that observed with the use of high alumina parts, and at Chelyabinsk Electrometallurgical Plant it was higher only in the upper portion of ladles in comparison with that obtained with the normally used fired periclase parts.During service in ladles the parts do not spall, become encrusted at a metal temperature of 1620 °C, do not become encrusted at 1790°C, and at 2200°C are eroded by slag.Translated from Ogneupory, No. 7, pp. 16–20, July, 1982.  相似文献   
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