非线性延迟积分微分方程单支方法的散逸性

本文研究了非线性延迟积分微分方程单支方法的散逸性．把G（c3P30）-代数稳定的单支方法应用到以上方程中,得到了在有限维空间和无限维空间的散逸性结果．文章最后,数值试验验证了本文的结论．     

基于α分布的单矢量传感器多目标方位估计

研究 稳定分布条件下单矢量传感器的多目标方位估计问题。介绍多维 稳定分布特征函数的谱测度表示及谱测度估计方法,在此基础上推导出单矢量传感器输出速度正交分量满足特征函数谱测度表示方程,建立谱测度与目标方位间的对应关系,用特征函数法或一维投影法估计谱测度和目标源方位及数量。仿真结果表明,在 稳定分布假设下,基于谱测度的多目标方位估计法是合理有效的。     

Computing Only Minimal Answers in Disjunctive Deductive Databases

A method is presented for computing minimal answers of the form in disjunctive deductive databases under the disjunctive stable model semantics. Such answers are constructed by repeatedly extending partial answers. Our method is complete (in that every minimal answer can be computed) and does not admit redundancy (in the sense that every partial answer generated can be extended to a minimal answer), thus no non-minimal answer is generated. The method does not (necessarily) require the computation of models of the database in their entirety. A partitioning of the database into extensional and intensional components is employed in order to overcome the problems caused by the possible non-existence of disjunctive stable models, and a form of compilation is presented as a means of simplifying and improving the efficiency of the run-time computation, which then reduces to relatively trivial processing within the extensional database. In addition, the output from this compilation process has the significant advantage of being immune to updates to the extensional database. Other forms of database pre-processing are also considered, and three transformations are presented mapping a database onto an equivalent positive database, non-disjunctive database, and set of conditional facts.     

Synchronisation of a fractional-order chaotic system using finite-time input-to-state stability

The issue of synchronisation for a fractional-order chaotic system with uncertainties and disturbance is studied in this paper. The finite-time input-to-state stable theory of fractional-order dynamical system is presented for the first time. A linear feedback controller is proposed to achieve synchronisation of this fractional-order system and guarantee the bounded state error for any bounded interference in finite time. Since the chaotic system displays special dynamical behaviours as invariable Lyapunov exponent spectrums and controllable signal amplitude, one can achieve complete synchronisation and projective synchronisation by only adjusting the system parameter. Numerical simulations are shown to verify the feasibility of the presented synchronisation scheme.     

H∞ filtering for piecewise homogeneous Markovian jump nonlinear systems

This paper concerns the problem of H_∞ filtering for piecewise homogeneous Markovian jump nonlinear systems. Different from the existing studies in the literatures, the existence of variations in transition rates for Markovian jump nonlinear systems is considered. The purpose of the paper is to design mode-dependent and mode-independent filters, such that the dynamics of the filtering errors are stochastic integral input-to-state stable with H_∞ performance index. Using the linear matrix inequality method and the Lyapunov functional method, sufficient conditions for the solution to the H_∞ filtering problem are derived. Finally, three examples are proposed to illustrate the effectiveness of the given theoretical results.     

Stability radius of implicit dynamic equations with constant coefficients on time scales

This paper deals with the stability radii of implicit dynamic equations on time scales when the structured perturbations act on both the coefficient of derivative and the right-hand side. Formulas of the stability radii are derived as a unification and generalization of some previous results. A special case where the real stability radius and the complex stability radius are equal is studied. Examples are derived to illustrate results.     

Estimation of the Bivariate Stable Spectral Representation by theProjection Method

A method of estimating the spectral representation of a generalized bivariatestable distribution is presented, based on a series of maximum likelihood (ML)estimates of the stable parameters of univariate projections of the data. Thecorresponding stable spectral density is obtained by solving a quadraticprogram. The proposed method avoids the often arduous task of computing themultivariate stable density, relying instead on the standard univariate stabledensity. The paper applies this projection procedure, under the simplifyingassumption of symmetry, to simulated data as well as to foreign exchangereturn data, with favorable results. Kanter projection coefficients governingconditional expectations are computed from the estimated spectral density. For the simulated data these compare well to their known true values.     

设计不安于“弃”——永续性环保设计

工业设计主要研究的是人、产品、环境三者之间的关系。所以好的工业设计产品要同时满足环境和人的心理的需要。本文以此为出发点,基于现在环境的恶化和人们之间的冷漠提出"永续性环保设计(Sustainable design)"的理念。通过介绍现今社会环境,提出此设计理念并提出了其设计方法。     

周期环境下的最优的脉冲控制策略

研究了周期环境影响下具有脉冲控制的捕食与被捕食模型的全局动态行为,通过Floqnet理论和微分方程比较定理,得到了捕食系统害虫根除周期解的全局稳定性的临界值,进一步数值模拟分析了系统参数如何影响害虫综合控制,得到了最优的脉冲控制策略．