In order to prevent cracking appeared in the work-piece during the hot stamping operation,this paper proposes a hybrid optimization method based on Hammersley sequence sampling( HSS),finite analysis,backpropagation( B...In order to prevent cracking appeared in the work-piece during the hot stamping operation,this paper proposes a hybrid optimization method based on Hammersley sequence sampling( HSS),finite analysis,backpropagation( BP) neural network and genetic algorithm( GA). The mechanical properties of high strength boron steel are characterized on the basis of uniaxial tensile test at elevated temperatures. The samples of process parameters are chosen via the HSS that encourages the exploration throughout the design space and hence achieves better discovery of possible global optimum in the solution space. Meanwhile, numerical simulation is carried out to predict the forming quality for the optimized design. A BP neural network model is developed to obtain the mathematical relationship between optimization goal and design variables,and genetic algorithm is used to optimize the process parameters. Finally,the results of numerical simulation are compared with those of production experiment to demonstrate that the optimization strategy proposed in the paper is feasible.展开更多
此处 C 是某个常数,J 是 n×n 的全1方阵.用图论的术语可把 A 看成某个 n 阶有向图G=(V,E)的相邻矩阵.即如记 V={x_1,x_2,…,x_n),则弧(x_i,x_j)∈E,当且仅当a_(ij)=1.这样得到的图 G 称为 A 所对应的图.如果 A 是方程(1)在约束(2)...此处 C 是某个常数,J 是 n×n 的全1方阵.用图论的术语可把 A 看成某个 n 阶有向图G=(V,E)的相邻矩阵.即如记 V={x_1,x_2,…,x_n),则弧(x_i,x_j)∈E,当且仅当a_(ij)=1.这样得到的图 G 称为 A 所对应的图.如果 A 是方程(1)在约束(2)—(4)下的解,则对应的图 G 应具性质:展开更多
针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization ...针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization Algorithm Based on Mixed Strategy,JRBMO)。首先,引入Hammersley序列初始化种群,使初始解分布更均匀,为寻优提供基础;其次,在勘探阶段,提出自适应螺旋围捕策略,通过动态控制个体的勘探范围与方向,提高RBMO的搜索能力。在开发阶段,引入莱维飞行策略,对当前最优解进行局部扰动,增强算法局部开发能力;最后,提出自适应维度变异策略,根据种群适应度分布的变化,对个体进行维度变异,避免算法陷入局部最优。在CEC2017与CEC2019测试集上对算法性能进行评估,结果显示JRBMO均值胜率分别达到88.9%和70%,验证了JRBMO的有效性。此外,将JRBMO应用于拉(压)弹簧设计问题和三维无线传感器网络(WSN)节点覆盖问题上,JRBMO均取得了最优的结果,其中WSN节点均值覆盖率高出原算法6.3%,体现了JRBMO在实际应用中的普适性。展开更多
基金Sponsored by the Fundamental Research Funds for the Central Universities(Grant No.CDJZR14130006)
文摘In order to prevent cracking appeared in the work-piece during the hot stamping operation,this paper proposes a hybrid optimization method based on Hammersley sequence sampling( HSS),finite analysis,backpropagation( BP) neural network and genetic algorithm( GA). The mechanical properties of high strength boron steel are characterized on the basis of uniaxial tensile test at elevated temperatures. The samples of process parameters are chosen via the HSS that encourages the exploration throughout the design space and hence achieves better discovery of possible global optimum in the solution space. Meanwhile, numerical simulation is carried out to predict the forming quality for the optimized design. A BP neural network model is developed to obtain the mathematical relationship between optimization goal and design variables,and genetic algorithm is used to optimize the process parameters. Finally,the results of numerical simulation are compared with those of production experiment to demonstrate that the optimization strategy proposed in the paper is feasible.
文摘此处 C 是某个常数,J 是 n×n 的全1方阵.用图论的术语可把 A 看成某个 n 阶有向图G=(V,E)的相邻矩阵.即如记 V={x_1,x_2,…,x_n),则弧(x_i,x_j)∈E,当且仅当a_(ij)=1.这样得到的图 G 称为 A 所对应的图.如果 A 是方程(1)在约束(2)—(4)下的解,则对应的图 G 应具性质:
文摘针对红嘴蓝鹊优化算法(Red-billed Blue Magpie Optimization Algorithm,RBMO)存在多样性迅速退化、寻优精度差、易陷入局部最优的问题,提出了一种基于混合策略的自适应红嘴蓝鹊优化算法(Adaptive Red-Billed Blue Magpie Optimization Algorithm Based on Mixed Strategy,JRBMO)。首先,引入Hammersley序列初始化种群,使初始解分布更均匀,为寻优提供基础;其次,在勘探阶段,提出自适应螺旋围捕策略,通过动态控制个体的勘探范围与方向,提高RBMO的搜索能力。在开发阶段,引入莱维飞行策略,对当前最优解进行局部扰动,增强算法局部开发能力;最后,提出自适应维度变异策略,根据种群适应度分布的变化,对个体进行维度变异,避免算法陷入局部最优。在CEC2017与CEC2019测试集上对算法性能进行评估,结果显示JRBMO均值胜率分别达到88.9%和70%,验证了JRBMO的有效性。此外,将JRBMO应用于拉(压)弹簧设计问题和三维无线传感器网络(WSN)节点覆盖问题上,JRBMO均取得了最优的结果,其中WSN节点均值覆盖率高出原算法6.3%,体现了JRBMO在实际应用中的普适性。
