供应链中随机需求车辆选径问题的研究

结合供应链的需要给出了允许两次服务失败的数学模型,提出了一种混沌神经网络求解算法,对该问题进行了求解,并与SA算法进行了比较.结果表明该算法具有很强的避免陷入局部极小点的能力,较大地提高了优化的性能和搜索效率,适用于求解车辆选径问题.     

蚁群算法求解双弹性模量桁架结构反问题

利用光滑函数和有限元技术,建立了求解弹性双模量桁架结构的正问题数值模型,推导了敏度计算公式,并采用Newton-Raphson算法进行求解,在正问题建模的基础上,利用蚁群算法对拉压弹性模量进行识别,并探讨了参数取值范围和数据噪音对识别结果的影响,计算结果表明蚁群算法可有效地求解不同模量桁架反问题。     

基于代理模型的功能梯度梁的材料特性参数反求

针对功能梯度材料参数的反求问题,提出了一种基于代理模型的反求方法。应用有限元软件建立功能梯度梁的波动响应模型,获得模型在激振力作用下的动态位移响应。通过试验设计选取合理的样本点,建立响应面模型代替有限元软件作为程序的正问题求解器,遗传算法作为反问题求解器,用添加不同噪声水平的峰值位移来模拟反求模型的实际输入作为整个算法的输入数据,最终获得材料的体积参数。以实际SiC-C功能梯度梁为算例,分析了单次正弦激振力下,有限元软件获得的动态响应,并根据获得的位移响应应用遗传算法来反求SiC-C梁的体积分数。算例验证了本方法的有效性。基于代理模型的反求方法避免了多次调用正问题求解器,提高了计算效率。      

反求点在自由曲面上投影参数值的一种稳定算法

针对反求曲线曲面上点的参数值存在数值不稳定的问题,提出了一种稳定的算法.实际应用的曲面很多采用高阶次曲面并且由很多曲面片拼接而成,采用NURBS曲面形式记录曲面信息.针对这类复杂曲面,采用牛顿迭代法求解参数值,再采用单纯形法对参数值进行优化.通过上百个数据的试验,证明该算法是反求点在自由曲面上投影的参数值的一种稳定的并有效的算法.     

面向高度时变不确定患者需求的急诊医生周排班方法研究

本文对急诊医生的周计划排班问题进行研究,建立了基于马尔科夫链模型和均匀化方法的系统定量评估方法,并设计禁忌搜索算法对问题加以求解优化。为了减少算法的计算时间,设计了三种算法运算求解加速策略。本文利用上海、武汉等三甲医院的真实数据对算法优化后的医生排班方案与目前实际排班进行了比较,在病人等待时间等多个指标上分析了求解结果的优势。     

基于信息熵改进的粒子群算法在桁架结构

提出了信息熵改进的粒子群优化算法用于解决有应力约束、位移约束的桁架结构杆件截面尺寸优化设计问题.首先介绍了信息熵基本理论和基本粒子群优化算法理论,然后对粒子群优化算法作了合理的参数设置,并将信息熵引入粒子群优化算法的适应函数和停机判别准则中.最后对2个经典的优化问题进行求解并与其他算法进行了比较.数据结果表明信息熵改进后的粒子群优化算法在桁架结构优化设计中优于其他同类算法.     

基于密度峰值聚类的VRPTW问题研究

提出一种密度峰值聚类 (density peak clustering, DPC)与遗传算法(genetic algorithm, GA)相结合的新型混合算法(density peak clustering with genetic algorithm, DGA),求解带时间窗的车辆路径问题。首先应用DPC对客户进行聚类以缩减问题规模,再将聚类后的客户用GA进行线路优化。结果表明：DGA在9个数据集上的平均值比模拟退火(simulated annealing, SA)和禁忌搜索(Tabu)分别提高了13.41%和4.7%,单个数据集最大提高了26.4%。这证明了该算法是求解车辆调度问题的高效算法。     

线性约束下反Hermitian 广义反Hamiltonian 矩阵的最佳逼近问题

讨论了线性约束下反Hermitian广义反Hamiltonian矩阵的最佳逼近问题.提出并证明了约束矩阵集合SA非空的充分必要条件,给出了集合SA中元素的一般表达式.对于任意一个复矩阵,得到了它在SA中的最佳逼近矩阵A*的表达式.     

矩阵圈选算法求解TSP问题

提出了TSP问题(旅行商问题)的一种新的近似算法,即矩阵圈选算法.该算法通过对加权距离矩阵的特征判断构造圈,并不断对圈进行改进和更新的方法找出TSP问题的近似解.从TSPLIB国际标准数据集中抽取了一组数据.通过对比说明本算法对于求解TSP问题十分有效.     

蝙蝠算法在PFSP调度问题中的应用研究

针对新生的启发式智能算法蝙蝠算法求解离散型生产调度问题存在的局限性,利用对蝙蝠算法重新编码以及初始化的方式来求解离散型生产调度问题。通过对经典的生产调度基准数据进行测试,并同较成熟的标准粒子群算法进行比较。结果表明,蝙蝠算法在解决离散的生产调度问题时,具有较好的优化性能。验证了蝙蝠算法求解离散性问题的有效性以及可行性。     

A simulated annealing algorithm for balancing the assembly line type II problem with sequence-dependent setup times between tasks

This paper addresses the general assembly line balancing problem where the simple version is enriched by considering sequence-dependent setup times between tasks. Recently, Andres et al. (Andres, C., Miralles, C., and Pastor, R., 2008. Balancing and scheduling tasks in assembly lines with sequence-dependent setup times. European Journal of Operational Research, 187, (3), 1212–1223.) proposed the type I general assembly line balancing problem with setups (GALBPS-I) and developed a mathematical model and several algorithms for solving the problem. In a similar vein, we scrutinised the GALBPS type II problem where the challenge is to find the minimum cycle time for a predefined number of work stations. To solve the problem, we develop a mathematical model and a novel simulated annealing (SA) algorithm to solve such an NP-hard problem. We then employed the Taguchi method as an optimisation technique to extensively tune different parameters of our algorithm and make the classical SA algorithm more efficient in terms of running time and solution quality. Computational results reflected the high efficiency of the SA algorithm in both aspects.     

基于改进模拟退火算法的复合材料层合板频率优化

针对复合材料层合板频率优化问题,结合可行规则法和直接搜索模拟退化算法,提出了一种自适应模拟退火(SA)改进算法。层合板优化目标是基频、频率带隙以及给定基频和带隙约束的层合板厚度。设计变量包括铺层角度和铺层数两种离散变量。改进算法的自适应新点产生模块采用依赖温度的动态调整搜索半径,改善了直接搜索模拟退化(DSA)算法易陷入局部极值的缺陷,而可行规则法的引入提高了SA算法求解约束问题的效率和简易性。采用Ritz法进行频率响应分析以考虑弯扭耦合影响。不同铺层数、角度增量和长宽比时的层合板3类算例结果显示:改进算法能有效求解层合板频率优化,可获得更多或更好的铺层顺序全局优化解。     

基于资源约束的装配线平衡问题研究

在生产线建立过程中,必须考虑人员、设备等资源和作业约束,基于此,本文建立一种含有并行工作站的装配线平衡模型,并利用模拟退火算法求解该模型．经仿真验证,该算法能够求出满足模型约束条件的最优方案或可行方案,并且能够得到不同方案的多个目标属性值,这不仅表明算法的有效性,还给决策者的方案选择提供了一定的空间．     

Multiparameter retrieval of water optical properties from above-water remote-sensing reflectance using the simulated annealing algorithm

Water-leaving radiance, measured just above the ocean surface, contains important information about near-surface or subsurface processes that occur on or below the deep ocean and coastal water. As such, retrieving seawater inherent optical properties (IOPs) is an important step to determining water type, subsurface light field, turbidity, pigment concentration, and sediment loading. However, the retrieval (or inversion) of seawater IOPs from just above water radiance measurements is a multiparameter nonlinear problem that is difficult to solve by conventional optimization methods. The applicability of the simulated annealing algorithm (SA) is explored as a nonlinear global optimizer to solve this multiparameter retrieval problem. The SA algorithm is combined with widely known semianalytical relations for seawater's IOPs to parameter invert these properties from simulated and measured water-leaving reflectance spectra. Furthermore, given the versatility of the SA algorithm, the scheme is extended to retrieve water depth from input reflectance data. Extensive tests and comparisons with in situ and simulated data sets compiled by the International Ocean-Color Coordinating Group are presented. Field data include reflectance spectra acquired with a handheld GER 1500 spectroradiometer and absorption measurements, performed with the AC-9 instrument on waters around Singapore's nearby islands.     

Cloud manufacturing resources fuzzy classification based on genetic simulated annealing algorithm

To solve the problem of fuzzy classification of manufacturing resources in a cloud manufacturing environment, a hybrid algorithm based on genetic algorithm (GA), simulated annealing (SA) and fuzzy C-means clustering algorithm (FCM) is proposed. In this hybrid algorithm, classification is based on the processing feature and attributes of the manufacturing resource; the inner and outer layers of the nested loops are solving it, GA obtains the best classification number in the outer layer; the fitness function is constructed by fuzzy clustering algorithm (FCM), carrying out the selection, crossover and mutation operation and SA cooling operation. The final classification results are obtained in the inner layer. Using the hybrid algorithm to solve 45 kinds of manufacturing resources, the optimal classification number is 9 and the corresponding classification results are obtained, proving that the algorithm is effective.     

Simultaneous determination for a space-dependent heat source and the initial data by the MFS

In this paper we propose a numerical algorithm based on the method of fundamental solutions for recovering a space-dependent heat source and the initial data simultaneously in an inverse heat conduction problem. The problem is transformed into a homogeneous backward-type inverse heat conduction problem and a Dirichlet boundary value problem for Poisson's equation. We use an improved method of fundamental solutions to solve the backward-type inverse heat conduction problem and apply the finite element method for solving the well-posed direct problem. The Tikhonov regularization method combined with the generalized cross validation rule for selecting a suitable regularization parameter is applied to obtain a stable regularized solution for the backward-type inverse heat conduction problem. Numerical experiments for four examples in one-dimensional and two-dimensional cases are provided to show the effectiveness of the proposed algorithm.     

FMS machine loading: A simulated annealing approach

In this paper the problem of FMS machine loading is considered with the objective of minimizing the system imbalance using a simulated annealing (SA) approach. New job sequences are generated with a proposed perturbation scheme named the 'modified insertion scheme' (MIS). These sequences are used in the proposed simulated annealing algorithm to arrive at a near global optimum solution. A new approach for temperature variation in the SA algorithm is also suggested in which temperature is assumed to be parabolic. The SA algorithm using the proposed MIS and the assumed temperature variation proved to be giving substantial improvement in system imbalance as against conventional sequences.     

流体饱和孔隙介质参数反演的模拟退火算法

本文研究了模拟退火算法在流体饱和孔隙介质参数反演中的应用。通过计算响应数据与实测响应数据的拟合将参数反问题归结为最优化问题。由于流体饱和孔隙介质运动方程的复杂性，动力响应与材料参数之间呈复杂的非线性关系，优化目标函数是非凸多峰函数。传统的梯度类优化方法一方面受局部极值的困扰难以搜索到全局最优解； 另一方面确定搜索方向须进行复杂的参数敏度分析。为克服这些困难，本文应用模拟退火算法进行了多参数反演数值模拟，模拟结果表明了模拟退火算法的可行性和稳健性。     

Scheduling in flowshops to minimize total tardiness of jobs

The problem of scheduling in static flowshops is considered with the objective of minimizing mean or total tardiness of jobs. A heuristic algorithm based on the simulated annealing (SA) technique is developed. The salient features of the proposed SA algorithm are the development of two new perturbation schemes for use in the proposed SA algorithm and a new improvement scheme to improve the quality of the solutions. The proposed algorithm is evaluated by using the benchmark problems available in the literature. The performance of the proposed SA algorithm is found to be very good, and the proposed heuristic performs better than the existing heuristics.