不确定分数阶Qi系统有限时间同步控制

基于有限时间同步理论研究分数阶不确定Qi系统的有限时间同步,能够使系统误差有限时间收敛到原点.获得驱动响应系统有限时间同步充分条件,研究表明:一定条件下,分数阶不确定Qi系统的主从系统是有限时间同步的.     

基于相空间重构的混沌投影同步观测器设计

基于相空间重构技术和极点配置方法,设计了一类混沌系统的投影同步状态观测器.利用系统的一个状态变量及其对时间的各阶导数就可使观测器和被观测系统以任意比例因子实现同步.以四阶超混沌系统为例进行数值仿真,仿真结果证明了设计方法的有效性.     

不确定临界混沌系统的有限时间同步与参数识别

针对不确定临界混沌系统,研究了它的有限时间同步和参数识别.基于有限时间李雅谱诺夫稳定性理论以及自适应控制技术,通过分步骤,设置合适的控制器,分别使得在参数具有扰动和参数完全未知的情况下,不确定的驱动系统和响应系统达到有限时间同步;同时,对参数未知的驱动系统,利用有限时间同步识别出未知参数.最后的数值模拟验证了所提出的方法的正确性和有效性.     

集装箱码头桥机调度问题基于完工时间下界的算法

关注单船桥机调度问题,指出了单船桥机的闲置会影响码头整体的运作效率。以单个集装箱为任务单位,考虑桥机移动时间、安全距离等约束,建立了最小化桥机完工时间和闲置时间的多目标规划模型。基于完工时间下界的两种不同情况:以重点贝位工作量确定和以平均工作量确定,分别设计了基于邻域搜索的启发式算法和基于贪心策略的"分割贝位"算法,并且证明了在以平均工作量确定下界的情况中该算法不会导致桥机闲置。不同规模、不同下界类型的算例表明:提出的模型与算法得到的桥机调度计划更适合实际生产作业,能够有效地逼近完工时间下界,算法运行速度较现有的研究有显著的提高。     

基于分布式极大独立集的无线传感器网络组网算法研究

运用图论理论,提出分布式无线传感器网络有效网络划分算法(RMIS)以实现WSN可靠数据传输需求.算法各节点间连通度和能量为优化约束,采用随机分布式极大独立集理论进行监测网格划分.数学证明算法在经过期望松弛同步轮数为O(log n)轮收敛.通过仿真分析,依RMIS算法划分网格可有效提高数据融合效率,减少数据传输平均距离,提高网络运行稳定性.     

集装箱码头桥机调度问题基于完工时间下界的算法

关注单船桥机调度问题,指出了单船桥机的闲置会影响码头整体的运作效率。以单个集装箱为任务单位,考虑桥机移动时间、安全距离等约束,建立了最小化桥机完工时间和闲置时间的多目标规划模型。基于完工时间下界的两种不同情况：以重点贝位工作量确定和以平均工作量确定,分别设计了基于邻域搜索的启发式算法和基于贪心策略的“分割贝位”算法,并且证明了在以平均工作量确定下界的情况中该算法不会导致桥机闲置。不同规模、不同下界类型的算例表明：提出的模型与算法得到的桥机调度计划更适合实际生产作业,能够有效地逼近完工时间下界,算法运行速度较现有的研究有显著的提高。     

基于参数自适应控制的分数阶离散logistic映射同步

讨论了分数阶离散混沌系统驱动系统和相应系统都是相同混沌映射、但是参数不同时的同步问题,采用了参数自适应算法实现了分数阶离散logistic映射的同步,并且给出了同步的充分条件.     

一个修正的PVT算法

对Fkshima(1998）所提出的PVT算法给出一种修正算法，称为修正PVT算法，这一修正算法对PVT原算法中的并行步中的停止准则和同步步骤作了修正。修正PVT算法的停止条件对PVT原算法的停止条件弱，因此更适用于并行计算，并且计算时间比PVT原算法少。     

基于自适应模糊控制方法的四翼混沌系统有限时间同步

研究了一类带有未知外部摄动的四翼混沌主从系统的有限时间同步控制问题.首先,基于自适应模糊控制方法,对四翼混沌系统的不确定项进行了处理.其次,基于Lyapunov有限时间稳定性准则,设计了一种有限时间同步控制器,使得主系统与从系统能在有限时间内实现状态同步.最后,通过数值仿真,检验了该方法的有效性和鲁棒性.     

基于熵权与模糊综合评价模型的城市交通运行效率测度——以南京市为例

为测度城市交通运行效率并探寻提升效率的有效途径,构建了基于熵权的城市交通运行效率的模糊综合评价模型,从城市空间结构、城市居民出行结构、城市交通基础设施水平和城市交通管理水平4个层面选择了城市人口密度等14个具体指标构建了城市交通运行效率评价体系,并对南京市2011-2015年的城市交通运行效率进行了测度与分析评价.研究结果表明:2011-2015年南京市的城市交通运行效率值分别为0.3131、0.3017、0.4203、0.5265和0.7214,整体呈现逐年上升的趋势;其中2011-2013年南京的城市交通运行效率较低,2014年为中等水平,2015年达到较高水平;要提升南京城市交通运行效率,可以从影响效率的关键性因素指标入手以取得较为显著的成效,包括加强道路网密度、提高居民公交出行比例、增加交通信号控制系统覆盖率、降低交叉口阻塞率和缩短事故后交通恢复时间等.     

Qualitative Analysis of Bifurcating Solutions in the Lengyel-Epstein Model

One of the most fundamental problems in theoretical biology is to explain the mechanisms by which patterns and forms are created in the＇living world. In his seminal paper ＂The Chemical Basis of Morphogenesis＂, Turing showed that a system of coupled reaction-diffusion equations can be used to describe patterns and forms in biological systems. However, the first experimental evidence to the Turing patterns was observed by De Kepper and her associates（1990） on the CIMA reaction in an open unstirred reactor, almost 40 years after Turing＇s prediction. Lengyel and Epstein characterized this famous experiment using a system of reaction-diffusion equations. The Lengyel-Epstein model is in the form as follows     

RECENT PROGRESS ON SPHERICAL HARMONIC APPROXIMATION MADE BY BNU RESEARCH GROUP ——In memory of Professor Sun Yongsheng

As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years （2001-2005）. The main topics are： convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.     

(0,1 ;0)-INTERPOLATION ON INFINITE INTERVAL (-∞, +∞)

In this paper, we study the explicit representation and convergence of (0, 1; 0)-interpolation on infinite interval, which means to determine a polynomial of degree ≤ 3n - 2 when the function values are prescribed at two set of points namely the zeros of Hn(x) and H′n(x) and the first derivatives at the zeros of H′n(x).     

On a class of self-similar processes with stationary increments in higher order Wiener chaoses

We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.     

On a class of Riemann surfaces

It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.     

A REPRESENTATION FORMULA RELATED TO SCHR(O)DINGER OPERATORS

Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.     

Boundedness for commutators of multipliers on Hardy type spaces

In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p（R^n） into the Lebesgue space L^p with p 〈 1.     

A unified approach to certain problems of best local approximation

In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.     

Journal of the Operations Research Society of China Special issue on Operations Research in Healthcare Management

正Guest Editors:Hong Chen,Shanghai Jiao Tong University,Shanghai,China Guohua Wan,Shanghai Jiao Tong University,Shanghai,China David Yao,Columbia University,New York,USA Scope:Healthcare delivery worldwide has been fraught with high cost,low efficiency and poor quality of patient care service.For the field of operations research(OR),healthcare offers some of the biggest challenges as well as best opportunities in