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991.
In this paper,the optimal control of time-varying neutral control systems is investigated by means of the Maxmium Principle of time-delay systems.optimal control law is given. Then sub-optimal control of time-varying neutral control systems is studied by using sensitivity approach. Algorithm for suboptimal control is given. 相似文献
992.
The first synthesis of 3(S),17-dihydroxytanshinone was achieved by ultrasound promoted Diels-Alder reaction of the protected 3-hydroxymethyl-4,5-benzofurandione with a vinylcyclohexene derivative. Bioassay showed that the synthetic 3(S),17-dihydroxytanshinone was active in vitro against HL-60 tumor cell line by MTT method. 相似文献
993.
HUANG Wen-Hua ZHANG Jie-Fang 《理论物理通讯》2004,42(7)
Using the variable separation approach, many types of exact solutions of the generalized (2 1)-dimensional Nizhnik-Novikov-Veselov equation are derived. One of the exact solutions of this model is analyzed to study the interaction between a line soliton and a y-periodic soliton. 相似文献
994.
Ruifeng Yue Liang Dong Litian Liu 《International Journal of Infrared and Millimeter Waves》2006,27(7):995-1003
This paper presents a monolithic uncooled 8 × 8 bolometer array with polycrystalline silicon-germanium (poly-SiGe) thermistors
as active elements. The poly-SiGe films are deposited by ultrahigh vacuum vapor deposition (UHV/CVD) system and the dependence
of the temperature coefficient of resistance (TCR) on annealing temperature has been investigated. To decrease the thermal
conductance of the bolometer, the poly-SiGe thermistor was formed on a four leg suspended microbridge. The improved porous
silicon micromachining techniques described here enable the integration of the bolometer array with the MOS readout circuitry.
The measurements and calculations show that the mean responsivity is 1.07 × 104 V/W with an uncorrected uniformity of 10.5% and a thermal response time of 10.5 ms, and the detectivity of 3.75 × 108 cm Hz1/2/W is achieved at a chopping frequency of 30 Hz and a bias voltage of 5 V. 相似文献
995.
Zhang Guofen Xia Yan Xu Ganggang 《高校应用数学学报(英文版)》2006,21(4):397-404
A renewable component with exponential failure and repair times is considered, and its instantaneous availability at time t is denoted by A(t). This paper proposes two methods for constructing lower confidence limits of A(t) with Chebyshev inequation and generalized p-value approach. 相似文献
996.
HUANGZHENGAO WANGGUOQIU 《高校应用数学学报(英文版)》1996,11(4):475-486
This paper consists of two parts. The first part introduces the strict aspiration as a new aspiration solution concept, which is proved to be existent for any cooperative game. The second part deals with the unsolved problem put forward by Bennett [1] by showing that there is at least one payoff which is balanced, partnered and equal gains aspiration. The proof is algebraic and constructive, thus providing an algorithm for finding such aspirations. 相似文献
997.
MA Zheng-Yi ZHU jia-Min ZHENG Chun-Long 《理论物理通讯》2004,42(10)
A novel phenomenon that the localized coherent structures of a (2 1)-dimensional physical model possess fractal behaviors is revealed. To clarify the interesting phenomenon, we take the (2 1)-dimensional Boiti-Leon Pempinelli system as a concrete example. Starting from an extended homogeneous balance approach, a general solution of the system is derived. From which some special localized excitations with fractal behaviors are obtained by introducing some types of lower-dimensional fractal patterns. 相似文献
998.
Silvia Vogel 《Mathematical Programming》1992,56(1-3):91-119
In this paper we assume that a deterministic multiobjective programming problem is approximated by surrogate problems based on estimations for the objective functions and the constraints. Making use of a large deviations approach, we investigate the behaviour of the constraint sets, the sets of efficient points and the solution sets if the size of the underlying sample tends to infinity. The results are illustrated by applying them to stochastic programming with chance constraints, where (i) the distribution function of the random variable is estimated by the empirical distribution function, (ii) certain parameters have to be estimated. 相似文献
999.
The mathematical theory of elasticity for planar pentagonal quasicrystals is developed and some analytic solutions for a class
of mixed boundary-value problems (corresponding to a Griffith crack) of the theory are offered. An alternate procedure and
a direct integral approach are proposed. Some analytical solutions are constructed and the stress and displacement fields
of a Griffith crack in the quasicrystals are determined. A basis for further studying the mechanical behavior of the material
related to planar defects is provided.
Project supported by the Foundation of State Education Commission of China for Doctorate Station. 相似文献
1000.
利用经验Bayes方法,我们提出了一套选择带控制的最优Logistic总体的方案,并给出了择优统计量的收敛速度. 相似文献