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31.
The unified chaotic system contains the Lorenz system and the Chen system as two dual systems at the two extremes of its parameter
spectrum. This paper presents the design of bang bang controller for unified system and multitude of numerical experiments
under various control parameters. Numerical experiments meet the theoretic proof perfectly and convincingly demonstrated the
controller can be effectively used for unified systems with uncertainty of the equilibrium points. The method enriches the
applications of chaotic control.
Foundation item: Supported by the National Natural Science Foundation of China(50209012)
Biography: Deng Xiao-ming (1980-), male, Master candidate, research direction: chaos control. 相似文献
32.
筒型基础系缆平台沉/拔过程侧摩阻力原型测试 总被引:7,自引:1,他引:6
介绍了1999年首次安装在渤海锦州9-3地区多筒基础平台安装施工过程中的侧摩阻力原型测试研究,描述了简型基础上沉和上拔过程中筒壁侧摩阻力的测试系统和测试方法,给出了主要测试结果并与现行规范进行了对比分析,这项成果对筒型基础平台的设计和施工具有直接的参考意义。 相似文献
33.
以浓硫酸为催化剂,采用微波辐射技术,由间苯二酚与乙酰乙酸乙酯缩合制备7-羟基-4-4甲基香豆素。结果表明,微波辐射合成7-羟基-4-4甲基香豆素的最以应条件为:间苯二酚5.5g,乙酰乙酸乙酯6.8ml,浓硫酸1.5ml,微波功率240W,微波辐射时间6min,产率84.1%,不采用微波辐射,反应时间大于10h,产率78%,红外光谱分析表明,7-羟基-4-4甲基香豆素的特征峰与7-羟基-4-甲基香豆素的各官能团的吸收峰吻合,测定7-羟基-4-甲基香豆素的熔点为189-192℃。 相似文献
34.
在形状记忆合金中,存在马氏体穿晶生长现象,它是热弹马氏体相变在小角晶界的行为。 相似文献
35.
Itknownthatsmallamountsoffluxonthesurfaceofstainlesssteelcanincreasethedepthofweldpene trationinTIGweldingbyafactorofthree[1] .Thisprocessisreferredtoas”ATIG”orTIGweldingacti vatedbyflux .Therehavebeenthreepublishedphys icalmechanismsthatarepossiblecontri… 相似文献
36.
从计划角度重点分析了钢铁生产中炼钢、连铸、热轧三者之间联接的较高模式-直接热装轧制计划系统的实现方式,并给出了较为具体的方案。 相似文献
37.
本文以糠醇为原料,以醇作溶剂,在酸性条件下糖醇开环制得一系列乙酞丙酸酯类化合物。然后再以乙酞丙酸酯类化合物为原料,制得一系列未见报道的此类酯与醇的缩合产物,并用HP5988GC-MS联用仪研究了反应产物的组成。 相似文献
38.
LIUYan HUYi-jun 《武汉大学学报:自然科学英文版》2004,9(4):399-403
We consider a risk model with a premium rate which varies with the level of free reserves. In this model, the occurrence of claims is described by a Cox process with Markov intensity process, and the influence of stochastic factors is considered by adding a diffusion process. The integro-differential equation for the ruin probability is derived by a infinitesimal method. 相似文献
39.
J. Bruce Brackenridge 《Archive for History of Exact Sciences》2003,57(4):313-336
In the 1687 Principia, Newton gave a solution to the direct problem (given the orbit and center of force, find the central force) for a conic-section
with a focal center of force (answer: a reciprocal square force) and for a spiral orbit with a polar center of force (answer:
a reciprocal cube force). He did not, however, give solutions for the two corresponding inverse problems (given the force
and center of force, find the orbit). He gave a cryptic solution to the inverse problem of a reciprocal cube force, but offered no solution for the reciprocal square force. Some take this omission as an indication that Newton could not solve the reciprocal square, for, they ask, why else
would he not select this important problem? Others claim that ``it is child's play' for him, as evidenced by his 1671 catalogue
of quadratures (tables of integrals). The answer to that question is obscured for all who attempt to work through Newton's
published solution of the reciprocal cube force because it is done in the synthetic geometric style of the 1687 Principia rather than in the analytic algebraic style that Newton employed until 1671. In response to a request from David Gregory
in 1694, however, Newton produced an analytic version of the body of the proof, but one which still had a geometric conclusion.
Newton's charge is to find both ``the orbit' and ``the time in orbit.' In the determination of the dependence of the time on orbital position, t(r), Newton
evaluated an integral of the form ∫dx/x
n
to calculate a finite algebraic equation for the area swept out as a function of the radius, but he did not write out the
analytic expression for time t = t(r), even though he knew that the time t is proportional to that area. In the determination
of the orbit, θ (r), Newton obtained an integral of the form ∫dx/√(1−x2) for the area that is proportional to the angle θ, an integral he had shown in his 1669 On Analysis by Infinite Equations to be equal to the arcsin(x). Since the solution must therefore contain a transcendental function, he knew that a finite
algebraic solution for θ=θ(r) did not exist for ``the orbit' as it had for ``the time in orbit.' In contrast to these two
solutions for the inverse cube force, however, it is not possible in the inverse square solution to generate a finite algebraic
expression for either ``the orbit' or ``the time in orbit.' In fact, in Lemma 28, Newton offers a demonstration that the
area of an ellipse cannot be given by a finite equation. I claim that the limitation of Lemma 28 forces Newton to reject the
inverse square force as an example and to choose instead the reciprocal cube force as his example in Proposition 41.
(Received August 14, 2002)
Published online March 26, 2003
Communicated by G. Smith 相似文献
40.
Zhongsheng WANG Zhigang ZENG Xiaoxin LIAODepartment of Control Science Engineering Huazhong University of Science Technology Wuhan Hubei P. R. China 《系统科学与系统工程学报(英文版)》2003,12(2):204-209
Some stability criteria are obtained for a class of uncertain systems with time-delay usingLyapunov functional and analytic techniques. It is easy to check the criteria by making use of theboundedness of the uncertainties. 相似文献