Hopfield-型网络求解优化问题的一般演化规则

基于离散Hopfield-型网络和延迟离散Hopfield-型网络求解优化问题提出了两种一般 演化规则,演化序列的动态阈值是这些规则的重要特征,并获得了收敛性定理.推广了已有的 离散Hopfield-型网络和延迟离散Hopfield-型网络的收敛性结果,给出了能量函数局部极大值 点与延迟离散Hopfield-型网络的稳定态的关系的充分必要条件.鉴于延迟离散Hopfield-型网 络更有效地应用于优化计算问题,给出了一般分解策略.实验表明与离散Hopfield-型网络的 算法相比,文中提出的算法既有较高的收敛率又缩短了演化时间     

流水车间成组工件调度问题的多目标优化算法

针对优化目标是最小化全部提前/拖期和机器调整次数的多目标流水车间成组工件调度问题,提出了一种改进的变权重进化算法结合延迟调整算法的联合优化方法。首先采用改进的变权重进化算法对加工排序进行寻优;其次,在给定调度序列的情况下采用延迟调整算法对加工时刻进行优化。仿真实验表明,所设计的算法能够有效地求解该类问题。     

一种基于搜索路径识别的CDCL命题逻辑求解器延迟重启算法

适当的重启有助于求解器跳出局部最优,但频繁重启会严重降低效率。为解决CDCL求解器重启触发条件随意性大的问题,提出一种基于搜索路径识别的延迟重启算法。该算法使用Luby序列触发延时重启判断,将当前搜索路径和已搜索路径转换为向量空间模型,通过计算向量空间相似度来判断当前搜索过程是否会进入重复搜索空间。若向量空间相似度达到设定阈值,则触发重启,否则延迟重启。采用SAT国际竞赛的实例,与两个主流的求解器进行了对比实验。结果表明,所提算法能够有效规避重复搜索空间问题,并显著提高求解效率。     

求解不动点方程的人工鱼群算法*

基于传统迭代算法在求解不动点方程的过程中求解结果与初始点选取有很大关系且很难满足并行性的要求,提出了一种求解不动点方程的改进人工鱼群算法。该算法实现了求解不动点方程的并行性,克服了初始点的影响,同时把Cauchy序列引入到觅食行为中,提高整个算法的求解精度和速度。仿真实验验证了该算法的有效性。     

一种新的时间序列分析算法及其在股票预测中的应用

分析了股票市场高度非线性的特点,给出了一种改进的时间序列分析算法。新算法利用径向基网络来对序列中的历史信息进行非线性组合,从而比基于线性组合的时间序列分析算法的基本模型更能有效地挖掘出序列中历史信息之间的相互作用。新算法还利用改进的遗传算法对径向基函数的中心和宽度进行了全局范围的优化选择,进一步提高了径向基网络的非线性映射能力。运用该算法对股票走势进行了预测,取得了令人满意的效果。     

基于状态压缩的最长公共上升子序列快速算法

探讨了最长公共上升子序列（LCIS）问题,在前人算法的基础上提出一种高效求解LCIS的动态规划算法。对于LCIS问题,分别使用最长公共子序列（LCS）和最长上升子序列（LIS）相结合的算法、动态规划算法、经过状态压缩的改进动态规划算法进行设计,并对后两种算法进行了实现。设计的状态压缩的动态规划算法,实现了LCIS的快速求解。通过分析这三种算法的时间和空间复杂度,最终提出了时间复杂度为O（mn）、空间复杂度为O（m）或O（n）的基于状态压缩的快速LCIS算法。     

一种多径信道直扩信号伪码序列盲估计方法

针对多径信道下直接序列扩频信号伪码序列盲估计的难题,拓展了基于加性高斯白噪声信道提出的子空间法,提出了一种基于子空间法和三阶相关函数法相结合的多径信道直扩信号伪码序列盲估计的新算法,进行了理论推导。该算法对接收到的多径直扩信号按照伪码周期的两倍进行分段形成数据向量,构造自相关矩阵并进行特征值分解得到不同增益伪码序列的延迟叠加,运用m序列的三阶相关特性估计生成多项式进而估计伪码序列。计算机仿真结果验证了该算法的有效性。     

室内环境下基于图像序列拓扑关系的移动机器人全局定位

针对室内环境结构相似的特点,提出一种基于图像序列拓扑关系的移动机器人全局定位算法.首先,提取图像的Gist描述子,并提出一种局部极值算法,将环境划分成若干组不同的图像序列.然后,使用ESN(echo state network)对每一组图像序列在时间上进行双序训练,提取鲁棒的图像序列特征,再利用空间上的双向匹配策略实现图像序列特征的匹配.最后,采用HMM(hidden Markov model)对图像序列间的拓扑关系进行建模,将移动机器人全局定位问题转化成有向无环图中最长路径求解问题,并通过实验对该图像序列划分和序列建模方法进行验证.与基于单帧图像匹配的算法、SeqSLAM算法以及Fast-SeqSLAM算法相比,该算法在室内走廊环境和办公环境中均可实现100%的定位.特别是在室内办公环境中,机器人仅需要运动0.80 m便可以对自身进行准确定位.实验结果表明,该算法具有较强的鲁棒性、较高的定位准确性和定位效率.     

一种鲁棒的动作分类方法

针对无动态性的动作识别中易受噪声、干扰和遮挡等影响的问题,提出了一种基于稀疏表示的鲁棒的动作分类方法。对要测试的动作表示成所有训练动作的稀疏线性组合,并扩展该稀疏表示方程使其包含错误项,通过对系数和错误项的l1范数最小化算法来求解其最稀疏的表示,根据所得的稀疏解基于最小剩余量进行分类。并在Weizmann鲁棒性测试序列上进行了评价,实验结果表明该算法对噪声、干扰和部分遮挡具有较好的鲁棒性。     

基于人工鱼群算法的混杂FMS优化调度

针对已有的调度方法难以找到混杂柔性制造系统调度全局最优解的问题,根据一阶混杂Petri网模型提出了一种基于人工鱼群算法的混杂柔性制造系统调度方法.利用混杂Petri网不变行为状态序列与时间序列的对应关系把寻找最优解转换成寻找最优时间序列.首先给出了合法时间序列的定义及其基于人工鱼群算法的判定方法;然后给出了最优时间序列求解的人工鱼群算法,同时提出基于最优解视野变异的人工鱼群算法以解决多次优化过程中只会得到某个局部最优解的问题.最后基于这些算法给出混杂柔性制造系统的最优调度求解方法.实验结果表明所提出方法正确有效.     

线性递归Da taL og 程序优化算法

提出了线性齐次ＤａｔａＬｏｇ逻辑程序的概念,并为该类程序设计了一个优化的求解算法。在此基础上提出了求解一般线性ＤａｔａＬｏｇ程序的优化算法,该算法利用带有的约束条件的递归调用方法,将线性ＤａｔａＬｏｇ程序求解问题变换成齐次程序的求解问题。算法简单,易于实现,可应用于任何线性ＤａｔａＬｏｇ程序的求解。     

Optimization of a Data Dependence Graph for the Local Microcode Compaction Problem. Part 2: Algorithms and Experimental Verification

Structuring of the computational scheme of the method for solving the exchange permutability problem for a linear segment of a microcode on shared static resources is discussed. For each element of the structure formed, an algorithm is developed, and its correctness and computational complexity are studied. Applications of the results of solving the above problem to the local compaction of a horizontal microcode are considered. Numerical experiments with large amounts of source data substantiate high computational efficiency of the new approach to solving the local compaction problem.     

A numerical algorithm for optimal control of a class of hybrid systems: differential transformation based approach

A novel numerical algorithm based on differential transformation is proposed for optimal control of a class of hybrid systems with a predefined mode sequence. From the necessary conditions for optimality of hybrid systems, the hybrid optimal control problem is first converted into a two-point boundary value problem (TPBVP) with additional transverse conditions at the switching times. Then we propose a differential transformation algorithm for solving the TPBVP which may have discontinuities in the state and/or control input at the switching times. Using differential transformation, the hybrid optimal control problem reduces to a problem of solving a system of algebraic equations. The numerical solution is obtained in the form of a truncated Taylor series. By taking advantage of the special properties of the linear subsystems and a quadratic cost functional, the differential transformation algorithm can be further simplified for the switched linear quadratic optimal control problem. We analyse the error of the numerical solution computed by the differential transformation algorithm and some computational aspects are also discussed. The performance of the differential transformation algorithm is demonstrated through illustrative examples. The differential transformation algorithm has been shown to be simple to be implemented and computationally efficient.     

On a general optimal algorithm for multirate output feedbackcontrollers for linear stochastic periodic systems

A modified optimal algorithm for multirate output feedback controllers of linear stochastic periodic systems is developed. By combining the discrete-time linear quadratic regulation (LQR) control problem and the discrete-time stochastic linear quadratic regulation (SLQR) control problem to obtain an extended linear quadratic regulation (ELQR) control problem, one derives a general optimal algorithm to balance the advantages of the optimal transient response of the LQR control problem and the optimal steady-state regulation of the SLQR control problem. In general, the solution of this algorithm is obtained by solving a set of coupled matrix equations. Special cases for which the coupled matrix equations can be reduced to a discrete-time algebraic Riccati equation are discussed. A reducable case is the optimal algorithm derived by H.M. Al-Rahmani and G.F. Franklin (1990), where the system has complete state information and the discrete-time quadratic performance index is transformed from a continuous-time one     

Performance‐based near‐optimal vibration control for nonlinear offshore platforms with delayed input

This paper investigates the vibration control problem for offshore platform, where the nonlinear characteristics, delayed input and external wave force are considered in time domain. By introducing a delay‐free reconstructional vector and applying the maximum principle, the original vibration problem for offshore platform is formulated as a nonlinear two‐point‐boundary‐value (TPBV) problem with delayed items. The major contribution of this paper is that a performance‐based near‐optimal vibration control strategy is proposed by solving this nonlinear TPBV problem, which includes a feedback item with offshore platform system state, a feedforward item with wave force state, and a compensator for nonlinear and delayed items with infinite supersensitive component. In particular, the designed compensator is calculated from two group series of linear differential equations by introducing a parameter for expending the Maclaurin series of nonlinear and delay items. Meanwhile, an iterative algorithm is designed to make the proposed vibration control scheme computable based on the control performance in each iterative procedure. Finally, experimental results show that the displacement, velocity and performance index of an employed offshore platform achieved small values under the proposed control strategy and designed algorithm.     

Solving the conditional optimization problem for a fractional linear objective function on a set of arrangements by the branch and bound method

The exact combinatorial method of solving the problem of optimization on arrangements with a fractional linear objective function and additional linear constraints is considered. The branch and bound algorithm developed is based on the ideas of Land and Doig. An illustrative example of solving the optimization problem with a fractional linear objective function on arrangements with the algorithm is presented.     

基于m序列的信道编码信息隐藏算法

信道编码信息隐藏技术是一门新兴的信息隐藏技术。该文提出了一种基于m序列的信道编码信息隐藏算法。该算法采用m序列对秘密信息进行伪随机加扰，并利用m序列来选取秘密信息在码字载体中的嵌入位置。实验结果表明该隐藏算法具有较好的不可检测性和较高的安全性。     

具有模型和实际差异的非线性离散动态系统最优控制

针对模型与实际存在一定差异的情况,提出了一种求解非 线性离散系统最段控制的动态系统优化和参数估计集成（Ｄｙｎａｍｉｃ Ｉｎｔｅｇｒａｔｅｄ Ｓｙｓｔｅｍ Ｏｐｔｉｍｉｚａｔｉｏｎ Ｐａｒａｍｅｔｅｒ Ｅｓｔｉｍａｔｉｏｎ,简称ＤＩＳＯＰＥ）的研究法。推导出一组求解一类有终端等式约束的非齐次的线性两点边值问题的递推公式,对于有终端等式约束的非线线性最优控制问题得到了在计算上易于实现的一种ＤＩＳＯＰＥ     

基于m序列整数调制和置乱的图像加密算法

分析了m序列产生原理,分别提出了图像位置置乱的“m序列变换”方法和图像像素值替代的“m序列整数调制”方法,研究了m序列变换的图像加密效果。在此基础上,利用混沌图像的混沌特性,提出了一种实用的图像加密算法。最后,分析了本文算法的密钥空间和安全性,并给出了应用本文算法的图像加密结果。     

多项式泛函网络运算模型及应用

提出了一种多项式泛函网络运算新模型,来求解任意数域或环上多项式运算问题。同时给出了基于泛函网络求任意一元多项式倍式的学习算法,而网络的参数利用解线性方程组方法来完成。实验结果表明,这种神经计算方法,相对传统方法,不但能够获得问题的精确解,而且可获得问题的近似解。这给工程计算软件的二次开发提供了有效方法。