基于集员滤波器的故障诊断

针对具有未知但有界故障的时变系统,提出一种集员滤波的故障诊断方法,保证系统的状态、故障信号的值100%包含在上下界内.假设过程噪声、测量噪声和故障信号的值有界,采用S-过程方法和线性矩阵不等式(LMI)方法设计集员滤波器,最后运用递归优化算法对集员滤波器进行优化.所提方法不仅可以对故障大小进行估计,还能够检测出故障信号类型.数值仿真证明了该方法的可行性和有效性.     

具有状态约束的基因调控网络的集员滤波器研究

针对基因调控网络中切实存在状态约束现象,在考虑一类含时滞、参数不确定、噪声干扰的离散基因调控网络模型基础上设计一种集员滤波器,实现基因调控网络状态的估计.通过假设测量噪声是未知但有界的,采用LMI方法设计集员滤波器,获得滤波器的增益矩阵,运用递归优化算法对集员滤波器进行优化.最后,通过数值仿真证明了所提算法的有效性,实现了基因调控网络中的mRNA和蛋白质浓度的准确估计.     

线性系统在非线性等式约束下的集员卡尔曼滤波

为了解决运行系统要求的100%估计包含真实最小域的需要和计算机的实时计算问题,使用集员卡尔曼滤波算法解决非线性状态约束.采用最小迹椭球算法对状态向量的椭球域进行更新,同时分别在预测和滤波的2个阶段用投影的方法把没有约束的状态估计投影到有约束的状态估计表面来处理约束问题.最后将所设计的集员卡尔曼滤波器应用到汽车追踪实例中.实验结果表明:采用所提算法的系统只是在初始值有比较大的误差,在后续的跟踪过程中都能在最大最小界之内跟踪上真实值.所提算法相比于传统的卡尔曼算法,其误差能迅速减小.实例仿真结果证明了所提方法的可行性和有效性.     

具有状态约束的集员卡尔曼滤波器设计

针对状态约束问题,提出具有状态约束的集员卡尔曼滤波算法.采用最小迹椭球算法对状态向量的椭球域进行更新,同时分别在预测和滤波的两个阶段用投影的方法把没有约束的状态估计投影到有约束的状态估计表面处理约束问题.将所设计的集员卡尔曼滤波器应用到三维追踪实例中,实例仿真结果证明了所提方法的可行性和有效性.     

滑模观测器实现不确定系统的鲁棒故障重构

讨论了利用滑模观测器实现不确定系统的在线故障重构问题.首先应用奇异值分解,对系统进行规范化处理,设计了鲁棒滑模观测器的LMI算法,并通过非线性介入使设计观测器对系统不确定性具有鲁棒性及跟踪系统状态的收敛性;然后根据滑模观测器设计方法,利用等价输出误差介入、H∞约束优化原理以及加入输出滤波器方法,提出了执行器故障和传感器...     

具有线性不等式约束非线性规划问题的降维算法

对线性约束的一般非线性规划问题进行了研究,在算法中提到的起作用集策略,与常见的起作用集算法相比较;在迭代过程中求解等式约束子问题时采用了降维算法,而对于不等式约束子问题采用了起作用集算法.通过数值试验,说明了算法的有效性.算法对于求解非线性约束非线性规划问题提出了一种新思路,将非线性约束线性化,解决一般此类问题.     

考虑状态约束的容积卡尔曼滤波估计算法

针对传统非线性滤波未考虑状态约束的局限,提出一种考虑状态约束的容积卡尔曼滤波算法。将状态约束转化为增益约束,结合最小方差估计给出最小约束代价函数;同时,采用相径容积规则近似计算系统状态的后验均值和协方差,给出等式状态约束下的容积卡尔曼滤波递推公式。最后,对路径约束条件下的导航定位系统进行仿真,结果表明算法定位精度优于常规容积卡尔曼滤波算法,较好地解决了非线性系统存在等式状态约束时、常规容积卡尔曼滤波算法不满足约束条件且估计精度差的问题,验证了算法的有效性。     

基于谱分解技术的两通道因果稳定IIR滤波器组的设计(英文)

提出一种新的两通道因果稳定IIR滤波器组的设计方法.首先基于所定义的一种余弦滚降IIR滤波器,两通道滤波器组所要求的平坦条件完全被满足;其次该方法是依赖于分析滤波器的功率谱特性,而不是该滤波器的幅度频率特性来设计滤波器组.IIR滤波器的设计问题可转化成一个准凸问题,采用凸优化算法来求解;然后对所得优化解进行谱分解,得到目标滤波器组.该滤波器组具有合理的完全重构误差,并且其多相因子的分母相同,简化了完全重构条件.采用该滤波器组作为约束非线性优化法的有效初值,进一步优化得到完全重构2通道IIR滤波器组.     

求解含等式约束优化问题的遗传算法

针对遗传算法较难处理含等式约束的优化问题,在设计变量独立性分析的基础上对等式约束采用了降维处理方法,不仅使等式约束在优化时始终严格满足,而且经降维处理后优化问题仅包含不等式约束;然后,借鉴多目标优化思想,提出了从个体违反约束程度和违反次数2方面同时对种群进行排序,使算法对个体的排序和选择更符合实际.实例验证了该算法的有效性和可行性.     

带饱和约束非线性系统的鲁棒自适应容错控制

针对发生执行器故障的饱和非线性系统提出一种主动容错控制方法.考虑系统存在的外界干扰情形,运用H∞控制结合饱和约束设计了自适应容错控制器.首先,引入饱和幅值以确保控制输入始终在界范围之内,设计包含故障估计值的自适应状态反馈控制输入;其次,为实现系统具有鲁棒稳定性,同时具有最大容错椭球体稳定域的控制目标,采用李雅普诺夫理论结合H∞控制方法,并运用不变集理论估计最大椭球体稳定域,将自适应容错控制器的设计方法转化为求解线性矩阵不等式约束下的多目标优化问题;最后,通过一数值算例将自适应与固定增益控制器设计方法进行对比分析.研究结果表明:自适应控制器的性能更优,更适合用于受饱和约束非线性系统的容错控制.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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