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91.
92.
93.
Jong-Hwan Kim Yeon-Chan Hong Sung-Jun Lee Keh-Kun Choi 《Industrial Electronics, IEEE Transactions on》1989,36(3):361-364
A direct adaptive control scheme is proposed for nonminimum-phase systems in which controller parameters are estimated from the recursive least-squares algorithm and additional auxiliary parameters are obtained from the proposed polynomial identity. A local convergence is guaranteed without any extra condition. Integral action is incorporated into the adaptive controller to eliminate the steady-state error and to satisfy a condition of the unique solution for the polynomial identity. The control law used in this scheme is based on the set-point-on-I-only proportional-integral-derivative (PID) structure 相似文献
94.
A graph G is N2‐locally connected if for every vertex ν in G, the edges not incident with ν but having at least one end adjacent to ν in G induce a connected graph. In 1990, Ryjá?ek conjectured that every 3‐connected N2‐locally connected claw‐free graph is Hamiltonian. This conjecture is proved in this note. © 2004 Wiley Periodicals, Inc. J Graph Theory 48: 142–146, 2005 相似文献
95.
Jeong Ryeol Choi 《International Journal of Theoretical Physics》2004,43(4):947-958
We derived the WKB wave function for the general time-dependent quadratic Hamiltonian system using a unitary transformation method. We applied our research to sinusodially drived Caldirola–Kanai oscillator and confirmed that the time evolution of our approximated WKB wave function is similar to that of the exact one. This wave function can be used to analyze the interference between the probability amplitudes contributed by the area of overlap in phase space of quantum states. 相似文献
96.
Sei‐ichiro Kawase 《International Journal of Satellite Communications and Networking》2005,23(1):67-76
This paper proposes a technique for monitoring the longitudinal motion of geosynchronous satellites. A two‐antenna interferometer is used, with the baseline orientation adjusted to a particular horizontal azimuth. The interferometer then becomes insensitive to the north–south motion of the satellite, and this enables direct measurement of the satellite's longitudinal motion. Longitudes are monitored continuously, with no delay when orbital manoeuvres occur. The proposed technique is particularly useful when two or more satellites are operating in close proximity and their longitudes must be precisely monitored for safety control. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
97.
A W-band divide-by-3 frequency divider with wide bandwidth and low power dissipation is presented using harmonic injection-locking technique. A cascode FET is employed for a self-oscillating second-harmonic mixer which is injection-locked by third-harmonic input to obtain the division order of three. The fabricated frequency divider using 0.1 /spl mu/m GaAs metamorphic HEMT technology shows superior performance such as large bandwidth of 6.1 GHz around 83.1 GHz (7.3%) under small DC power consumption of 12 mW. 相似文献
98.
Ching‐Yuan Cheng Kuan‐Jiuh Lin 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(8):m363-m365
In the title compound, catena‐poly[lithium‐μ3‐ethylenediphosphonato], [Li(C2H7O6P2)]n, the supramolecular monoclinic (C2/c) structure consists of one‐dimensional lithium chains [Li⋯Li = 2.7036 (8) Å] that are embedded within ethylenediphosphonate anions linked by strong symmetric hydrogen bonds [O⋯O = 2.473 (3) Å]. The Li atoms and the H atom in the symmetric hydrogen bond reside on twofold rotation axes and there is an inversion center at the mid‐point of the C—C bond of the ethylenediphosphonate ligand. 相似文献
99.
The inhomogeneous Dirichlet problems concerning divergence form elliptic equations are studied. Optimal regularity requirements on the coefficients and domains for the W1,p theory, 1 < p < ∞, are obtained. The principal coefficients are supposed to be in the John‐Nirenberg space with small BMO seminorms. The domain is a Reifenberg domain. These conditions for the W1,p theory not only weaken the requirements on the coefficients but also lead to a more general geometric condition on the domains. In fact, these domains might have fractal dimensions. © 2004 Wiley Periodicals, Inc. 相似文献
100.
Marcelino Maneiro Manuel R. Bermejo M. Isabel Fernndez Ana M. Gonzlez‐Noya Alexei M. Tyryshkin Robin G. Pritchard 《无机化学与普通化学杂志》2003,629(2):285-290
A new MnIII‐Schiff base complex, [MnL(OH2)](ClO4) ( 1 ) (H2L = N, N′‐bis‐(3‐Br‐5‐Cl‐salicylidene)‐1, 2‐diimino‐2‐methylethane), an inorganic model of the catalytic center (OEC, Oxygen Evolving Complex) in photosystem II (PSII), has been synthesized and characterized by elemental analysis, IR and EPR spectroscopy, mass spectrometry, magnetic susceptibility measurement and the study of its redox properties by cyclic and normal pulse voltammetry. This complex mimics reactivity (showing a relevant photolytic activity), and also some structural characteristics (parallel‐mode MnIII EPR signal from partially assembled OEC cluster) of the natural OEC. The complex 1 was found to rearrange in solution into a crystallographically solved square‐pyramidal complex, [MnLL′] ( 2 ) (HL′ = 6‐bromo‐4‐chloro‐2‐cyanophenol), through a process, which probably liberates radical species (detected by EPR), and provokes a C—N bond cleavage in the ligand. A photo‐radical mechanism is discussed to explain this rearrangement. 相似文献