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1.
In this paper, a locally computed suboptimal control strategy for a class of interconnected systems is introduced. First, optimal statefeedback control equations are derived for a finite-horizon quadratic cost. Then, the control for each subsystem is separated into two portions. The first portion stabilizes the isolated subsystem, and the second portion corresponds to the interactions. To achieve a locally calculable control, an approximation to the optimal control equations is introduced, and two iterative suboptimal control algorithms are developed. In the first algorithm, the initial conditions of subsystems are assumed to be known; in the second algorithm, this information is replaced by statistical distributions. The orders of errors in the iterations of the algorithm and in the suboptimality are given in terms of interconnections. An example with comparisons is also included to show the performance of the approach. 相似文献
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Ü. Kotta N. Sadegh 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(1):21-32
This paper studies the necessary and sufficient conditions for observable realization of a general class of nonlinear high-order input-output difference equations. In particular, it proves the equivalence of the two seemingly different existing approaches in the literature. The paper also provides a subclass of NARMA input-output models that are guaranteed to have an observable realization. It is shown that this class covers several important subclasses of existing NARMA models. 相似文献
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Thermal conductivity variations with temperature of solid phases for lauric acid (LA), myristic acid (MA), pivalic acid (PA), and stearic acid (SA) have been measured with radial heat-flow method. Temperature dependencies of the thermal conductivity for same organic materials have been obtained by linear regression analysis. From graphs of thermal conductivity versus temperature, the thermal conductivity of solid phase at their melting temperature and temperature coefficients of thermal conductivity for LA, MA, PA, and SA have been found to be 0.37, 0.39, 0.23, and 0.35 W K?1 m?1 and 0.00935, 0.00446, 0.01095, and 0.00295 K?1, respectively. The ratios of thermal conductivity of liquid phase to thermal conductivity of solid phase for LA, MA, PA, and SA have also been measured to be 0.52, 0.48, 0.25, and 0.59, respectively, with a Bridgman-type directional solidification apparatus. 相似文献
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Ü. Turgut E. Büyükkasap Ö. Şimşek M. Ertuğrul O. Doğan 《Journal of Radioanalytical and Nuclear Chemistry》1997,218(2):267-272
The total attenuation cross sections in elements Ti, Fe, Ni and Zn for K and K group of liens of element 22Z92 by using tranmission method. K X-rays of seconder excitor were counted by a Ge(Li) detector with resolution 190 eV at 5.9 keV. The experimentally mesured attentuation cross sections have ben found in a good agreement with the theoretical values of Stom, Israel and Hubbell, Seltzer. 相似文献
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Ratan K. Chaudhuri Fatama Ü. Afifi-Yazar Otto Sticher Tammo Winkler 《Tetrahedron》1980,36(16):2317-2326
The 13C NMR spectra of twenty one iridoid glucosides and fourteen acyl iridoid glucosides of various cyclopentane oxidation states have been analysed and their carbon shifts assigned. Evidence is presented which demonstrates that 13C NMR spectroscopy is a valuable and reliable technique for distinguishing the sites of acylation in iridoid glucosides and confirming the predictions of the configuration at C-6 and C-8. A cis configuration of vicinal substituents is generally associated with a substantial increase in shielding, as compared with the trans analog. The ring size and C-1 configuration in the glucose moiety are also evident from the spectra. 相似文献
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Optimal design of a rigid-plastic stepped beam is discussed assuming the mode form of motion. Such beam dimensions are sought for which a minimum of local or mean deflection is attained within designs of constant volume. It is assumed that the prescribed kinetic energy is imparted to the structure at the initial instant with free motion occurring afterwards. It is shown that besides three symmetric modes of motion, also the asymmetric modes may exist. An optimal design for asymmetric modes is determined and compared with a respective design for symmetric modes, obtained previously in [1]. 相似文献
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An analysis of diffusion paths in single-phase ternary metal systems Co–Fe–Ni and Cu–Fe–Ni on the basis of the phenomenological interdiffusion model using effective interdiffusion coefficients is presented. The peculiarities of practical application of effective interdiffusion coefficients of components for calculating diffusion paths in ternary systems are analysed. It is done on the basis of the relationship between effective interdiffusion coefficients and the diffusion paths. The results were found to be in good agreement with experimental data for the ternary systems Co–Ni–Fe and Cu–Ni–Fe. It is shown that deviation of the diffusion path from linearity in ternary single-phase diffusion couple in the system Cu–Ni–Fe mainly depends on the thermodynamic properties of the system. 相似文献
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Let ξ = (p 1, p 2,…) be a given infinite sequence of not necessarily distinct primes. In 1976, the structure of locally finite groups S(ξ) (respectively A(ξ) ) which are obtained as a direct limit of finite symmetric (finite alternating) groups are investigated in [7]. The countable locally finite groups A(ξ) gives an important class in the theory of infinite simple locally finite groups. The classification of these groups using the lattice of Steinitz numbers is completed by Kroshko and Sushchansky in 1998 see [8]. Here we extend the results on the structure of centralizers of elements to centralizers of arbitrary finite subgroups and correct some of the errors in the section of centralizers of elements in [8]. We construct for each infinite cardinal κ, a new class of uncountably many simple locally finite groups of cardinality κ as a direct limit of finitary symmetric groups. We investigate the centralizers of elements and finite subgroups in this new class of simple locally finite groups, and finally, we characterize this class by the lattice isomorphism with the cardinality of the group and the Steinitz numbers. 相似文献
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Ü. Demirezen H. Koru T. Koyoma 《Journal of Radioanalytical and Nuclear Chemistry》1993,172(2):223-230
In134Cs uptake by the roots of orchard grass and beans planted in three different lands of soil has been studied. For this purpose, a134Cs radionuclide solution having 0.3086 Ci/pot radioactivity was added to Ando, Serpentine and Alluial and Clay soil which were fertilized by Standard, –K, +Ca, Water limited and Control for both orchard grass and bean groups. Thus, the above mentioned groups have been harvested and left to dry. The contamination levels these plants have been detected and measured by using an HPGe detector interactively working with MCA. Finally, it has been determined that the134Cs uptakes depend primarily on soil characteristics. Besides the decrease in the134Cs activity for the plants grown in soils to which the stable cesium or potassium was added 0.011–1.38 per cent activity for the root of plants grown in free K soils was observed. Moreover, highest134Cs activity has been determined for the plants grown in –K fertilized soil with respect to the other soil samples. 相似文献