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121.
We study a linear discrete-time partially observed system perturbed by a white noise. The observations are transmitted to the estimator via communication channels with irregular transmission times. Various measurement signals may incur independent delays, arrive at the estimator out of order, and be lost or corrupted. The estimator is given a dynamic control over the sensors by taking part in producing the signals to be sent via the channels. The minimum variance state estimate and the optimal sensor control strategy are obtained. Ideas of model predictive control are applied to derive a nonoptimal but implementable in real time method for sensor control This work was supported by the Australian Research Council.  相似文献   
122.
The interaction of the [Ni(PPh3)3]BF4 complex with styrene and the products of styrene conversion in the polymerization reaction were studied by EPR and 13C NMR spectroscopy. The structure of the σ-carbocationic complex of Ni(I) formed by the interaction of styrene with the [Ni(PPh3)3]BF4 cationic phosphine complex of Ni(I) was characterized in detail. It was found that the reaction of styrene polymerization occurred with the participation of the coordination center of the σ-carbocationic complex (coordination catalysis), whereas the reaction of telomerization occurred with the participation of the cationic center of this complex (ionic catalysis). The resulting polymer contained active terminal double bonds; it is a promising macromonomer for the synthesis of grafted copolymers. The discovered capacity of alcohols to undergo nucleophilic addition to a growing polymer chain offers strong possibilities for preparing functional polymers and block copolymers.  相似文献   
123.
Abu Ali Ibn Sina [Avicenna] Tadzhik State Medical Institute, Dushanbe. Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 48–50, January–February, 1989.  相似文献   
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The reaction of oxides (epichlorohydrin, glycidol methyl ether, and ethylene oxide) with oxazolid-2-one and 2-imino-5-methyloxazolidine has been studied. It has been established that the oxides add in position 3 of the oxazolidine ring with the formation of the corresponding S-(-hydroxyalkyl) derivatives, the alkaline cleavage of which leads to mixed secondary amino alcohols.  相似文献   
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The kinetics of oxidative coupling of thiophene to bithiophene in the presence of Pd(OAc)2 in acetic acid solution has been studied at 60–80°C. The mechanism of the reaction is discussed.
Pd (OAc)2 HOAc 60–80°. .
  相似文献   
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The book describes modern methods of receiving laser signals, viz., by interferometry, by nonlinear optics, by laser amplification, and by heterodyne mixing. The theory of these methods is considered as applied to the problem of laser radars. Investigated in detail are features such as the resolving power of interferometry and nonlinear-optics method, the efficiency of parametric conversion of laser signals, the sensitivity of laser amplifiers, and problems of optimal heterodyne detection. Methods of speckle interferometry and adaptive optics are described. The book is aimed at a large circle of scientists and engineers active in the problem of recording of laser signals, as well as to students in advanced courses of the corresponding specialties.N. D. Ustinov — General Editor.Translated from Metody Obrabotki Opticheskikh Polei v Lazernoi Lokatsii, pp. 3–269, 1983.  相似文献   
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