基于克里金模型的潜水器耐压舱结构优化

本文研究Kriging建模和序贯加点相结合的方法,用于解决目标函数或者约束函数无法显式表达下的优化问题。在加点准则中为了避免出现龙格现象,改进了加点优化时步长要求,在优化过程中融入多种群遗传算法提高了序贯加点值的计算准确性。计算结果表明,改进后的加点准则在存在多区域或者多个极值点的情况下均可快速搜索到最优点位置。建立了载人潜水器载人舱以重量为优化目标,以强度要求为约束的球壳厚度优化模型,采用此方法在初始选取5个样本取样,序贯加点6个样本点,计算得到球壳的最优厚度值为50.5569 mm,可有效指导设计工作。     

一种多传感器航迹关联算法的仿真分析

多传感器航迹关联算法有好几种,本文对独立序贯航迹关联算法进行了仿真分析。可以看出,独立序贯航迹关联算法由于考虑了整个航迹历史,而且在算法中进行了航迹质量管理和多义性处理,因而其关联效果和质量还是比较高的,特别是在密集目标环境下,其正确关联概率较之在中等密度目标环境下的正确关联概率有了明显改善。     

基于ASM和FNN的人脸识别

将主动形状模型ASM(Active Shape Model)与模糊神经网络FNN(Fuzzy Neural Networks)相结合并用于人脸识别。针对经典ASM对初始化位置敏感、收缩速度慢的现象和传统模糊神经网络难以解决高维模式分类的问题进行了分析和改进。ORL人脸库上的试验表明了该算法的有效性。     

多传感器序贯势分布概率假设密度滤波

针对多传感器多目标跟踪中数据关联的计算复杂性问题,提出了一种多传感器序贯势分布概率假设密度滤波算法.利用序贯滤波的方法将单传感器的势分布概率假设密度滤波扩展到多传感器情况,并给出了高斯混合实现的序贯势分布概率假没密度(Gaussian mixture sequential PHD,GMSPHD)滤波的递推算法.仿真实验结果表明,文中提出的GMSCPHD滤波算法具有较高的多目标状态估计和目标数目估计精度,是一种有效的多传感器多目标跟踪方法.     

模糊支持向量机和独立成分分析在人脸识别中的应用

将独立成分分析(ICA)、模糊支持向量机(FSVM)以及三叉决策树相结合并应用于人脸识别.首先对人脸图像做独立成分分析,提取有利于分类的面部特征的主要独立成分,然后在特征空间中,用FSVM和三叉决策树相结合设计人脸分类器.在ORL人脸库上的实验结果表明,该算法能够取得较好的分类效果.     

基于模糊粒子滤波的视频跟踪方法研究

智能视频监控系统的基础就是对监控范围的视频序列中目标进行有效实时的跟踪,针对当前跟踪方法在光照突变、部分遮挡情况下的跟踪缺陷,本文提出了一种利用模糊粒子滤波（Particle Filter,PF）进行视频目标跟踪的新算法.该算法结合模糊控制理论,引入量测的模糊性来克服特征信息的不确定性,并建立一个基于背景建模技术的自适应高斯混合模型和基于序贯蒙特卡洛的跟踪算法（sequential Monte-Carlo-based）.在新算法的指导下,针对静止摄像机在光照条件改变以及目标发生部分遮挡的情况进行了深入的研究.通过多种模糊量测技术的比较和应用,本文方法实现了多个目标精确有效跟踪.     

一种新的模糊对称散布子空间的鉴别分析算法

提出一种模糊对称散布子空间的鉴别分析算法.首先通过构造对称散布子空间模型,分别获得类内和类间散布矩阵的一组子空间;其次引入了一种松弛归一化条件的模糊鉴别分析算法,根据每一个样本的隶属度对散布矩阵重定义所做的贡献,将它融入到特征抽取的过程中,从而得到完整有效的模糊特征向量集,解决了传统LDA方法中的最终特征维数受类别数限制的问题.在NUST603和ORL人脸数据库上的实验结果验证了该算法的有效性.     

基于核的四重子空间的LDA特征抽取方法

模式分类在面临非线性高维数据下的小样本问题时通常十分困难.文中提出了一种核的四重子空间学习(KFS)方法.首先通过构造基于类内和类间散布矩阵的混合鉴别准则,获得分布在各子空间中降维样本的最优鉴别信息.其次,通过向量点积,核鉴别分析方法(KFD)成为一种有效的抽取非线性鉴别信息的算法,在此基础上,提出了基于核的四重子空间鉴别分析算法,从而有效解决了非线性小样本问题的特征抽取.在ORL和Yale人脸库上的实验结果验证了该方法的有效性.     

模糊支持向量机和独立成分分析在人脸识别中的应用

将独立成分分析(ICA)、模糊支持向量机(FSVM)以及三叉决策树相结合并应用于人脸识别。首先对人脸图像做独立成分分析，提取有利于分类的面部特征的主要独立成分，然后在特征空间中，用FSVM和三叉决策树相结合设计人脸分类器。在ORL人脸库上的实验结果表明，该算法能够取得较好的分类效果。     

基于改进的混沌优化的翼滑艇推进系统仿真

通过Matlab平台建立翼滑艇推进系统的数学仿真模型,将翼滑艇的快速性指标和经济性指标的加权形式作为推进系统优化目标,并以Simulink进行实时仿真分析。首先,运用改进的混沌优化算法对模糊控制系统进行优化,求解最小控制目标值,然后对转速控制和螺距控制的控制器参数进行优化,并通过模糊控制器对不同工况下主机转速和可调桨螺距进行控制。最后,对比分析了常规模糊控制器与混沌算法优化后的模糊控制器之间的差别。结果表明,优化后的推进系统在进行航速控制时不仅超调量小,而且稳定性好,该优化方法有效可行。     

基于MPTC的船舶推进电机新型SMO

电力推进船舶是未来绿色船舶的重要发展方向。针对传统滑模观测器(SMO)应用在推进电机上的两个主要不足，在模型预测转矩控制策略(MPTC)的基础上提出一种新型SMO方案。针对传统SMO存在的抖振问题，利用Sigmoid函数代替sign函数对推进电机等效反电动势进行估计予以抑制，此外利用变截止频率低通滤波器以及锁相环技术消除传统SMO中低通滤波效应引起的相位延迟的同时提高转子转速和位置信息的观测精度。基于MATLAB/Simulink仿真平台验证了新型SMO具有更好的动、静态性能。     

动力定位船舶桨-桨干扰处理策略研究

本文针对动力定位船舶在推力分配中桨-桨之间的水动力干扰问题,基于二次规划算法提出了一种改进的避免桨-桨干扰的策略。以一艘海洋平台供应船模型为研究对象,通过仿真验证了该算法可以有效地降低推进器的推力损失,提高船舶的定位精度,降低推进系统的能耗。     

船体分段制造最低成本的二次规划模型及其求解

以分段建造费用与工时成线性关系为前提建立的船体分段制造最低成本数学模型其约束条件呈线性关系,目标函数边际收益递减,将最低成本模型改进为二次规划,利用EXCEL工具进行求解,实例计算逼近全局最优,方法简单实用.     

Hull-form optimization using parametric modification functions and particle swarm optimization

The focus of this paper is on devising designer-friendly hull-form variations coupled with optimization algorithms. Hull-form variations are carried out through parametric modification functions. Two kinds of representative optimization algorithms are considered here. One is the well-known sequential quadratic programming which is the derivative based. The other is particle swarm optimization which is the derivative free. The results applying these two algorithms to typical hull-form optimization problems are discussed in the paper. The technique using the parametric modification functions has been developed for modifying the ship’s geometry according to the widely recognized naval architect’s design practice. An original geometry can be easily deformed through the change of the variables of the modification functions; and useful information about the effect of the parameters is immediately obtained. Moreover, the variables of the modification functions can be considered as the design variables in the formulation of the optimization problem. For the performance prediction of the hull form, WAVIS version 1.3 is used for the potential-flow and RANS solver. Computational results for both single- and multi-objective problems are presented.     

基于分形理论和二次分割的图像裂缝特征提取方法与应用

在役跨海桥梁、港口工程等的服役环境恶劣，多数情况下采集到的裂缝图像背景复杂、噪声干扰较多。为了克服现有技术存在的不足，提出一种基于分形理论和二次分割的图像裂缝特征提取方法。该方法采用分形参数作为裂缝图像的特征参数，能优先抑制裂缝图像中产生干扰过多的问题，有效克服灰度不均匀、噪声块多和背景复杂的干扰因素，同时基于二次分割理论，结合两种不同的算法特点，利用粗分割排除干扰区域，利用细分割对目标区域内裂缝精准分割，实现混凝土结构裂缝目标准确有效的提取，具有更好的分割效果。     

变尺寸装箱问题的迭代/贪婪动态规划算法

针对船舶建造中管材切割规划这一类特殊的变尺寸装箱问题,提出了一种迭代贪婪/动态规划算法(IGDP)并对其进行求解.首先,提出了求解子集和问题的贪婪操作与动态规划的组合解法.然后,基于贪婪操作与动态规划的组合解法实现对整个问题的构造启发式求解,并且通过迭代的拆箱/再分配操作提高了算法的局部搜索能力.最后,通过8个算例的仿...     

基于模型预测的波能转换装置阵列的控制策略（英文）

To facilitate the commercialization of wave energy in an array or farm environment, effective control strategies for improving energy extraction efficiency of the system are important. In this paper, we develop and apply model-predictive control(MPC) to a heaving point-absorber array, where the optimization problem is cast into a convex quadratic programming(QP)formulation,which can be efficiently solved by a standard QP solver. We introduced a term for penalizing large slew rates in the cost function to ensure the convexity of this function. Constraints on both range of the states and the input capacity can be accommodated. The convex formulation reduces the computational hurdles imposed on conventional nonlinear MPC. For illustration of the control principles,a point-absorber approximation is adopted to simplify the representation of the hydrodynamic coefficients among the array by exploiting the small devices to wavelength assumption. The energycapturing capabilities of a two-cylinder array in regular and irregular waves are investigated. The performance of the MPC for this two-WEC array is compared to that for a single WEC, and the behavior of the individual devices in head or beam wave configuration is explained. Also shown is the reactive power required by the power takeoff system to achieve the performance.     

Model-Predictive Control Strategy for an Array of Wave-Energy Converters

To facilitate the commercialization of wave energy in an array or farm environment, effective control strategies for improving energy extraction efficiency of the system are important. In this paper, we develop and apply model-predictive control (MPC) to a heaving point-absorber array, where the optimization problem is cast into a convex quadratic programming (QP) formulation, which can be efficiently solved by a standard QP solver. We introduced a term for penalizing large slew rates in the cost function to ensure the convexity of this function. Constraints on both range of the states and the input capacity can be accommodated. The convex formulation reduces the computational hurdles imposed on conventional nonlinear MPC. For illustration of the control principles, a point-absorber approximation is adopted to simplify the representation of the hydrodynamic coefficients among the array by exploiting the small devices to wavelength assumption. The energy-capturing capabilities of a two-cylinder array in regular and irregular waves are investigated. The performance of the MPC for this two-WEC array is compared to that for a single WEC, and the behavior of the individual devices in head or beam wave configuration is explained. Also shown is the reactive power required by the power takeoff system to achieve the performance.

     

Hydrodynamic optimization of a catamaran hull with large bow and stern bulbs installed on the center plane of the catamaran

Here, a numerical optimization procedure is proposed for a fundamental study of a fast catamaran, and we compare the wave-making characteristics of a catamaran hull form with and without large bow and stern airship-type bulbs installed on the center plane of a catamaran operating at high speed. The method involves coupled ideas from two distinct research fields: numerical ship hydrodynamics and a nonlinear programming technique. The wave-making characteristics of catamaran hulls with and without bulbs were investigated using the panel method applied to free surface flow (PAFS), in which Morinos method for lifting bodies is extended to analyze the problem of free surface flow, and PAFS is linked to the optimization procedure of the sequential quadratic programming (SQP) technique. An optimum hull form for a catamaran can be obtained through a series of iterative computations, subject to some design constraints. Here, only the hull shape of a catamaran is optimized with and without center-plane bow and stern bulbs. The optimization is carried out at two Froude numbers, 0.45 and 0.5, which are around the last hump of the wave-making resistance curve. The numerical results show that a reduction in wave-making resistance is achieved around the design speed.     

铺管船锚泊定位系统优化设计研究

分析了铺管船锚泊定位系统的结构和它在海洋中的受力情况,研究了锚索悬链状态的特性.提出了锚泊定位系统的二次规划优化算法.目标函数定义为受力锚索的拉力的两两水平力差的平方和,受到线性等式或不等式锚索拉力的约束.求解采用Lagrange乘子法或凸二次规划的互补主元法.用面向对象的VC++工具开发了锚泊定位系统软件.对某铺管船的锚泊定位系统实例进行优化计算,得到满足环境力条件下锚索所承受的力和锚点位置,达到了设计要求.