On the Solution of the Eigenvalue Complementarity Problem by a Line Search Filter-SQP Algorithm

In this paper, the Eigenvalue Complementarity Problem (EiCP) with real symmetric matrices is addressed, which appears in the study of contact problem in mechanics. We discuss a quadratic programming formulation to the problem. The resulting problems are nonlinear programs that can be solved by a line search filter-SQP algorithm.

A Filter-Based Pattern Search Method for Unconstrained Optimization

We discuss a filter-based pattern search method for unconstrained optimization in this paper. For the purpose to broaden the search range we use both filter technique and frames, which are fragments of grids, to provide a new criterion of iterate acceptance. The convergence can be ensured under some conditions. The numerical result shows that this method is practical and efficient.

A NONMONOTONE LINE SEARCH FILTER METHOD WITH REDUCED HESSIAN UPDATING FOR NONLINEAR OPTIMIZATION

This paper proposes a nonmonotone line search filter method with reduced Hessian updating for solving nonlinear equality constrained optimization.In order to deal with large scale problems,a reduced Hessian matrix is approximated by BFGS updates.The new method assures global convergence without using a merit function.By Lagrangian function in the filter and nonmonotone scheme,the authors prove that the method can overcome Maratos effect without using second order correction step so that the locally superlinear convergence is achieved.The primary numerical experiments are reported to show effectiveness of the proposed algorithm.

Filtered-beam-search-based approach for operating theatre scheduling

To improve the efficiency of operating rooms,reduce the hospital's costs and improve the level of service qualities,a scheduling method is presented based on a filtered-beam-search-based algorithm.Firstly,a scheduling problem domain is described.Mathematical programming models are also set up with an objective function of minimizing related costs of the system.On the basis of the descriptions mentioned above,a solving policy of generating feasible scheduling solutions is established.Combining with the specific constraints of operation theatres,a filtered-beam-search-based algorithm is put forward to solve scheduling problems.Finally,simulation experiments are designed.The performance of the proposed algorithm is evaluated and compared with that of other approaches through simulations.Results indicate that the proposed algorithm can reduce costs,and are of practicality and effectiveness.

A Parallel String Searching Algorithm for Information Filtering

Playing an increasingly important role in the security protection of the network information systems,the intrusion detection system(IDS) becomes a hotspot of research interest nowadays.However,this technology in the kernel to many of these systems,namely string searching algorithm,has not received enough attention.By utilizing the concurrent mechanisms(multi-threading) provided by modern operation systems,such work can be divided symmetrically and thus improve the throughput of the corresponding application effectively.Presented in this work is a paralleled string searching algorithm-PBM,an algorithm based on the famous Boyer-Moore(BM) string searching algorithm.Taken as a dividable process,the string searching work is distributed between many cooperating threads of execution in the PBM algorithm,while each of them searches the target pattern in their respective share of the target strings.As compared with the traditional string searching algorithms,the PBM algorithm can do the pattern matching work faster by increasing the data processing throughput,thus adapting better to the drastic increase in the network band width.A simplification of the PBM algorithm that can be used as a multi-string searching algorithm is also suggested with supporting simulations,which is a promising approach when the number of target patterns is limited.

Design of Sharp 2D Multiplier-Less Circularly Symmetric FIR Filter Using Harmony Search Algorithm and Frequency Transformation

In this paper, we present a novel and efficient method for the design of a sharp, two dimensional (2D) wideband, circularly symmetric, FIR filter. First of all, a sharp one dimensional (1D) infinite precision FIR filter is designed using the Frequency Response Masking (FRM) technique. This filter is converted into a multiplier-less filter by representing it in the Canonic Signed Digit (CSD) space. The design of the FRM filter in the CSD space calls for the use of a discrete optimization technique. To this end, a new optimization approach is proposed using a modified Harmony Search Algorithm (HSA). HSA is modified in such a way that, in every exploitation and exploration phase, the candidate solutions turns out to be integers. The 1D FRM multiplier-less filter, is in turn transformed to the 2D equivalent using the recently proposed multiplier-less transformations namely, T1 and T2. These transformations are successful in generating circular contours even for wideband filters. Since multipliers are the most power consuming elements in a 2D filter, the multiplier-less realization calls for reduced power consumption as well as computation time. Significant reduction in the computational complexity and computation time are the highlights of our proposed design technique. Besides, the proposed discrete optimization using modified HSA can be used to solve optimization problems in other engineering disciplines, where the search space consists of integers.

光学多普勒差分流速仪数据解调方法验证

光学多普勒差分流速仪在测量海水流速时,由于信号微弱和噪声干扰,接收信号信噪比很低,信号解调面临挑战,可能导致较大的测量误差。为了准确解调埋藏在噪声中的信号并获取速度信息,需要对获取的海试测量数据进行进一步算法处理。采用自适应滤波算法有效降低了多普勒信号中混杂的高频噪声干扰,提高了海试原始数据频域信号的信噪比,并利用寻峰算法更准确地获取了谱峰值。结果表明,与直接读取原始数据的谱峰值相比,经过该算法处理后,激光差分多普勒流速仪与声学多普勒流速仪比测的流速拟合度平均误差为0.2163 cm/s,误差降低了25.5%,表明该算法对激光多普勒测速信号解调是有帮助的。

基于风速波动幅度动态划分区间的ISSA-BP风电功率预测

为了解决传统风电功率预测精度不高的问题,采用一种基于风速波动幅度动态划分区间的风电功率组合预测方法。首先,对清洗后的风速数据进行卡尔曼滤波得到去噪后的风速曲线图,计算该曲线中相邻元素的差值向量并归一化处理,完成风速波动幅度的可视化分析,依据波动幅度曲线的第一、二、三时间点将全年数据动态划分为4个区间;其次,利用Tent混沌映射算法初始化麻雀种群位置得到改进麻雀搜索算法(improvement sparrow search algorithm,ISSA),对误差反向传播算法(back propagation,BP)的连接权和阈值进行优化,建立ISSA-BP风电功率组合预测模型;最后,运用MATLAB仿真软件进行仿真验证。仿真结果表明,动态划分区间的ISSA-BP风电功率预测方法能显著提高预测精度,对提高电力系统经济运行水平,促进风电消纳具有一定的理论实际意义。

基于容忍因子的近似最近邻混合查询算法

近似最近邻搜索(ANNS)是计算机领域中一种重要的高效相似度搜索技术,可用于在大规模数据集中进行快速信息检索。随着人们对高精度信息检索的需求不断增长,同时使用结构化信息和非结构化信息进行混合查询的方式也得到了广泛应用。然而,基于近邻图的过滤贪心算法在混合查询时可能会因结构化约束条件的影响导致连通性降低,进而损害搜索精度。为此,提出了一种基于容忍因子的过滤贪心算法,通过容忍因子控制不满足结构化约束条件的顶点参与路由,在不改变索引结构的前提下维持原有近邻图的连通性,克服了结构化约束条件对检索精度的负面影响。实验结果证明,新算法可以在不同结构化约束强度下实现ANNS的高精度搜索,同时保持检索效率。该研究解决了基于近邻图的ANNS在混合查询场景中的问题,为大规模数据集的快速混合查询信息检索提供了一种有效的解决方案。

基于区块链的公平可验证搜索加密方案

针对现有搜索加密方案缺乏对数据拥有者行为约束的问题,提出了一种基于区块链的公平可验证搜索加密方案。该方案提供公平高效的搜索和验证。引入向量数字承诺约束数据拥有者行为,同时采用区块链计算哈希验证基准实现高效的轻量级多关键字搜索结果验证,避免第三方验证不可信问题。方案通过对偶编码算法函数和局部敏感哈希函数将关键字映射至布鲁姆过滤器中,实现模糊搜索的同时提高搜索前关键字转化为向量的效率。经实验表明,该方案搜索前关键字转化效率更高,验证过程与现有使用公钥密码原语的验证方案相比,时间消耗更少。安全性分析证明该方案在随机预言模型下是安全的。

基于Bloom Filter路由表的P2P搜索算法

研究非结构化P2P网络的搜索机制,提出基于布莱姆过滤器(BF)路由表的改进算法。该算法利用BF技术生成路由条目并在一定范围内相互交换本地路由表,使节点能够了解一定范围内的节点共享信息,实现有针对性的搜索,避免传统的盲目性搜索。仿真结果表明,该算法查询搜索时产生的消息数量比传统算法减少一个数量级,并能够获得较好的查全率。

非线性方程组的一个不使用罚函数和filter的算法

给出了求解非线性方程组的一个新算法,首先将非线性方程组转化为一个非线性规划,再使用一个不使用罚函数和filter的算法求解这个非线性规划,在Jacobi矩阵一致列满秩的条件下证明由算法产生序列的极限点是非线性方程组的解.通过在算法中引进二阶校正技术来克服可能的Maratos效应,可以证明这个方法是局部超线性收敛的.

改进布谷鸟算法优化粒子滤波的多目标跟踪方法

标准粒子滤波器的重采样会造成粒子贫化,影响跟踪系统的精度。为克服这一缺陷,提出了一种改进布谷鸟搜索算法优化粒子滤波的多目标跟踪方法。将粒子作为布谷鸟宿主鸟巢,模拟布谷鸟寻找宿主鸟巢位置的行为,通过全局搜索和局部搜索两个阶段使粒子向高似然区域移动。同时,改进布谷鸟搜索算法的寻优机制,提出动态搜索步长和强化局部搜索的方法,加强了算法的全局搜索的收敛速度。此外,改进算法结合了联合概率数据关联,用于解决多机动目标跟踪问题。本文设置了一维环境和二维环境两组实验,对比优化后的粒子滤波算法与标准粒子滤波算法的目标跟踪性能。实验结果表明,本文提出的算法不仅全局收敛速度更快,而且提高了多机动目标跟踪的精度;与标准布谷鸟搜索优化粒子滤波算法相比,全局收敛迭代速度提高了28.5%;与粒子滤波联合概率数据关联和粒子群优化粒子滤波联合概率数据关联算法相比,估计精度分别提高了24.7%和11.81%。

双层框架可视图下的双向跳点路径规划方法

针对移动机器人在复杂未知半未知环境下路径规划时间过长,难以找到全局最优路径的问题,该文提出了一种基于双层框架可视图的双向跳点搜索路径规划方法。首先,将可视图分为局部层和全局层,移动机器人通过传感器对环境信息进行采集与提取,生成局部可视图,接着采用基于障碍物轮廓边长的过滤方法将过滤后的图更新至全局可视图;其次,在跳点搜索算法的基础上新增一个从目标点开始搜索的路径,将跳点搜索算法优化为双向跳点搜索算法;最后,将优化后的算法结合可视图进行路径规划导航。将所提方法在多种复杂场景下进行验证,仿真实验表明:采用了双层框架可视图的双向跳点搜索算法的路径搜索时间和导航时间均有着不同程度的优化,可高效地在复杂未知环境下搜索全局路径。

考虑信号统计特征的神经网络室内测距方法

针对现有神经网络测距方法易陷入局部极值而降低测距精度的问题,提出一种考虑信号统计特征的神经网络蓝牙室内测距方法:提出一种反馈-卡尔曼混合滤波算法进行数据预处理;并分析接收信号的传播特性,引入信号统计特征参数作为输入信号,构建改进麻雀搜索算法优化的埃尔曼(Elman)神经网络(ISSA-Elman)测距模型。实验结果表明,该测距方法能够有效提高测距精度,平均测距误差约为15 cm。

基于SSA-VMD和ITFPF的喷油器信号去噪方法

由于柴油机工作环境复杂多变,喷油器信号中包含较多噪声,导致诊断率低。为降低噪声的影响,提高故障诊断率,提出一种麻雀算法优化变分模态分解(SSA-VMD)和改进时频峰值滤波(ITFPF)结合的信号去噪方法。针对VMD受分解参数制约的问题,以能量分解因子为目标函数,通过SSA自适应地将信号分解成一系列IMF,以解决参数设置不当导致的模态混叠问题。TFPF的窗长选择不当会影响其滤波效果,由于排列熵能够度量非平稳信号的复杂度,以排列熵为适应度函数寻到最优窗长,使ITFPF兼顾信号保真和噪声压制。仿真和试验结果表明:SSA-VMD和ITFPF结合的方法降噪效果优于其他方法,并使故障识别率相比未优化VMD提高了10.13%。

基于边缘与区域结合的光学遥感图像舰船分割方法

针对光学遥感图像中舰船目标分割精度低等问题,提出了一种基于边缘与区域结合的图像中舰船目标分割方法。首先,利用导向滤波改进Canny算法对待分割舰船遥感图像进行预处理,以保持边缘完整结构,得到舰船目标粗分割结果;然后,提出基于布谷鸟搜索优化的倒数灰度熵阈值选取方法进行舰船目标细分割;最后,引入形态学方法对分割结果进行修正,确保舰船目标的完整性。大量试验结果表明,该方法表现出较优的分割性能,为舰船检测识别领域提供了更好的分割方案。

DESIGN OF MAXIMALLY FLAT FIR FILTERS BASED ON EXPLICIT FORMULAS COMBINED WITH OPTIMIZATION

基于与退火模仿和随机相结合的明确的公式，搜索被介绍的一个格言联盟者公寓冷杉木过滤器设计方法。利用明确的公式计算起始的价值， finite-word-length 冷杉木过滤器设计问题被变换成过滤器系数的优化。与本地分离随机的搜索相结合并且模仿了退火的一个优化方法被建议，与在感觉 ofChebyshev 近似的最佳答案的结果。建议方法能简化冷杉木过滤器的设计过程并且减少计算负担。模拟结果显示建议方法比离开方法的传统的回合优异并且能把客观功能的价值归结为 41percent-74% 。

Cell Search Algorithm in Beyond 3G Systems

The downlink frame structure for beyond 3G mobile communication systems is presented. Beyond 3G systems utilize the OFDM technique. However, a problem encountered in OFDM is that channel dispersion destroys orthogonality between carriers, caushag inter-symbol interference. It is also sensitive to high peak to mean power ratio （PAPR）. Therefore it spends much time on obtaining frequency, time, and frame synchronization. This paper proposes to add a frame synchronization channel in the time domain to overcome the shortcoming of OFDM. As transmitter diversity improves the system performance, beyond 3G systems employ space-time block coded （STBC）. Fast cell search algorithm including slot synchronization, frame synchronization and cell ID identification is then discussed, which is based on the frame synchronization channel in transmitter diversity systems. Detection and false alarm probabilities in AWGN and Rayleigh channels are analyzed, and the mean acquisition time is obtained. Computer simulations are conducted to evaluate the performance of the cell search algorithm under different channel conditions.