针对目前旅行商问题的求解精度较差、容易陷入局部最优和收敛效果慢等缺点,根据模拟退火算法和大邻域搜索算法的特点,提出了一种基于大规模邻域搜索的模拟退火算法解决旅行商问题(simulated annealing algorithm with large neighborhoo...针对目前旅行商问题的求解精度较差、容易陷入局部最优和收敛效果慢等缺点,根据模拟退火算法和大邻域搜索算法的特点,提出了一种基于大规模邻域搜索的模拟退火算法解决旅行商问题(simulated annealing algorithm with large neighborhood search, SALNS)。上述算法在模拟退火的基础上修改算法的温度变化函数,构造旅行商问题的解空间,采用大邻域搜索技术和2-OPT算子增强局部搜索能力可以很好的解决旅行商问题。选取若干TSPLIB数据集进行实验,对降温函数和运行时间进行试验,并与一些新型智能算法对比。仿真结果表明,所提方法收敛效果好和鲁棒性强能够有效求解旅行商问题。展开更多
On the basis of the finite difference method, the factors affecting the temperature distribution along the thickness of plate during cooling process were analyzed, which include transformation heat, coefficient of hea...On the basis of the finite difference method, the factors affecting the temperature distribution along the thickness of plate during cooling process were analyzed, which include transformation heat, coefficient of heat conduction, specific heat, carbon content, cooling time, plate thickness, and unit of water flow volume. To ensure the homogenous temperature distribution along the thickness of plate, some cooling strategies, such as interval cooling, stepped cooling, and unsymmetrical cooling of upper and lower surfaces, were applied online. The online results showed that the cooling strategies can improve the temperature homogeneity greatly and the finite difference method can correctly simulate the cooling process.展开更多
文摘针对目前旅行商问题的求解精度较差、容易陷入局部最优和收敛效果慢等缺点,根据模拟退火算法和大邻域搜索算法的特点,提出了一种基于大规模邻域搜索的模拟退火算法解决旅行商问题(simulated annealing algorithm with large neighborhood search, SALNS)。上述算法在模拟退火的基础上修改算法的温度变化函数,构造旅行商问题的解空间,采用大邻域搜索技术和2-OPT算子增强局部搜索能力可以很好的解决旅行商问题。选取若干TSPLIB数据集进行实验,对降温函数和运行时间进行试验,并与一些新型智能算法对比。仿真结果表明,所提方法收敛效果好和鲁棒性强能够有效求解旅行商问题。
基金Item Sponsored by National Natural Science Foundation of China (50634030)National Key Technology Research and Development Program of China (2006BAE03A08)
文摘On the basis of the finite difference method, the factors affecting the temperature distribution along the thickness of plate during cooling process were analyzed, which include transformation heat, coefficient of heat conduction, specific heat, carbon content, cooling time, plate thickness, and unit of water flow volume. To ensure the homogenous temperature distribution along the thickness of plate, some cooling strategies, such as interval cooling, stepped cooling, and unsymmetrical cooling of upper and lower surfaces, were applied online. The online results showed that the cooling strategies can improve the temperature homogeneity greatly and the finite difference method can correctly simulate the cooling process.
