Due to the NP-hardness of the two-sided assembly line balancing （TALB） problem, multiple constraints existing in real applications are less studied, especially when one task is involved with several constraints. In ...Due to the NP-hardness of the two-sided assembly line balancing （TALB） problem, multiple constraints existing in real applications are less studied, especially when one task is involved with several constraints. In this paper, an effective hybrid algorithm is proposed to address the TALB problem with multiple constraints （TALB-MC）. Considering the discrete attribute of TALB-MC and the continuous attribute of the standard teaching-learning-based optimization （TLBO） algorithm, the random-keys method is hired in task permutation representation, for the purpose of bridging the gap between them. Subsequently, a special mechanism for handling multiple constraints is developed. In the mechanism, the directions constraint of each task is ensured by the direction check and adjustment. The zoning constraints and the synchronism constraints are satisfied by teasing out the hidden correlations among constraints. The positional constraint is allowed to be violated to some extent in decoding and punished in cost fimction. Finally, with the TLBO seeking for the global optimum, the variable neighborhood search （VNS） is further hybridized to extend the local search space. The experimental results show that the proposed hybrid algorithm outperforms the late acceptance hill-climbing algorithm （LAHC） for TALB-MC in most cases, especially for large-size problems with multiple constraints, and demonstrates well balance between the exploration and the exploitation. This research proposes an effective and efficient algorithm for solving TALB-MC problem by hybridizing the TLBO and VNS.展开更多
For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over ti...For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over time.Decaying has been proved to enhance generalization as well as optimization.Other parameters,such as the network’s size,the number of hidden layers,drop-outs to avoid overfitting,batch size,and so on,are solely based on heuristics.This work has proposed Adaptive Teaching Learning Based(ATLB)Heuristic to identify the optimal hyperparameters for diverse networks.Here we consider three architec-tures Recurrent Neural Networks(RNN),Long Short Term Memory(LSTM),Bidirectional Long Short Term Memory(BiLSTM)of Deep Neural Networks for classification.The evaluation of the proposed ATLB is done through the various learning rate schedulers Cyclical Learning Rate(CLR),Hyperbolic Tangent Decay(HTD),and Toggle between Hyperbolic Tangent Decay and Triangular mode with Restarts(T-HTR)techniques.Experimental results have shown the performance improvement on the 20Newsgroup,Reuters Newswire and IMDB dataset.展开更多
针对无人战斗机(unmanned combat air vehicle,UCAV)处于存在威胁区域的战场中路径规划问题,提出一种基于分组教与学算法的UCAV自适应路径规划方法。通过分析UCAV路径评价指标,提出一种自适应的UCAV路径评价模型,根据作战环境规划出距...针对无人战斗机(unmanned combat air vehicle,UCAV)处于存在威胁区域的战场中路径规划问题,提出一种基于分组教与学算法的UCAV自适应路径规划方法。通过分析UCAV路径评价指标,提出一种自适应的UCAV路径评价模型,根据作战环境规划出距离短、威胁小的任务路径。针对教与学算法寻优精度低、耗时长的问题,提出一种分组教与学算法,引入动态分组和高斯分布扰动策略,提高算法寻优性能。通过仿真实验,该方案求解的最优路径更短且安全。展开更多
为解决教与学优化算法容易早熟收敛的问题,在原算法的基础上提出一种基于混合策略改进的教与学优化算法(Mixed Strategy Based Improved Teaching-Learning Based Optimization,M-SITLBO)。首先,利用Logistic-Tent混沌映射策略初始化种...为解决教与学优化算法容易早熟收敛的问题,在原算法的基础上提出一种基于混合策略改进的教与学优化算法(Mixed Strategy Based Improved Teaching-Learning Based Optimization,M-SITLBO)。首先,利用Logistic-Tent混沌映射策略初始化种群,保证种群的多样性;其次,在教师和学生阶段分别引入黄金正弦算法和基于莱维飞行与对数螺旋线的搜索策略优化个体的位置更新公式,增强并平衡算法的全局和局部收敛性能;最后,设计仿真对其寻优性能进行测试,结果表明改进后的教与学优化算法寻优速度、精度以及稳定性显著提升,且具有较强跳出局部最优的能力。展开更多
针对舱段主动隔振系统中作动器配置优化问题,给出一种优化模型和方法,通过数值计算进行方法验证。首先建立了多通道舱段主动隔振系统的动力学模型,然后将作动器配置优化转换为约束0-1非线性规划问题,以系统监测点响应为优化目标函数,作...针对舱段主动隔振系统中作动器配置优化问题,给出一种优化模型和方法,通过数值计算进行方法验证。首先建立了多通道舱段主动隔振系统的动力学模型,然后将作动器配置优化转换为约束0-1非线性规划问题,以系统监测点响应为优化目标函数,作动器启用状态为自变量,最后采用教与学优化(teaching and learning-based optimization,TLBO)算法寻找最优配置。仿真计算结果表明,对于不同的激励,多通道主动隔振系统的最优配置不同,即存在对应给定激励下抑制壳体振动与声辐射的最优配置。展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.51275366,50875190,51305311)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20134219110002)
文摘Due to the NP-hardness of the two-sided assembly line balancing （TALB） problem, multiple constraints existing in real applications are less studied, especially when one task is involved with several constraints. In this paper, an effective hybrid algorithm is proposed to address the TALB problem with multiple constraints （TALB-MC）. Considering the discrete attribute of TALB-MC and the continuous attribute of the standard teaching-learning-based optimization （TLBO） algorithm, the random-keys method is hired in task permutation representation, for the purpose of bridging the gap between them. Subsequently, a special mechanism for handling multiple constraints is developed. In the mechanism, the directions constraint of each task is ensured by the direction check and adjustment. The zoning constraints and the synchronism constraints are satisfied by teasing out the hidden correlations among constraints. The positional constraint is allowed to be violated to some extent in decoding and punished in cost fimction. Finally, with the TLBO seeking for the global optimum, the variable neighborhood search （VNS） is further hybridized to extend the local search space. The experimental results show that the proposed hybrid algorithm outperforms the late acceptance hill-climbing algorithm （LAHC） for TALB-MC in most cases, especially for large-size problems with multiple constraints, and demonstrates well balance between the exploration and the exploitation. This research proposes an effective and efficient algorithm for solving TALB-MC problem by hybridizing the TLBO and VNS.
文摘For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over time.Decaying has been proved to enhance generalization as well as optimization.Other parameters,such as the network’s size,the number of hidden layers,drop-outs to avoid overfitting,batch size,and so on,are solely based on heuristics.This work has proposed Adaptive Teaching Learning Based(ATLB)Heuristic to identify the optimal hyperparameters for diverse networks.Here we consider three architec-tures Recurrent Neural Networks(RNN),Long Short Term Memory(LSTM),Bidirectional Long Short Term Memory(BiLSTM)of Deep Neural Networks for classification.The evaluation of the proposed ATLB is done through the various learning rate schedulers Cyclical Learning Rate(CLR),Hyperbolic Tangent Decay(HTD),and Toggle between Hyperbolic Tangent Decay and Triangular mode with Restarts(T-HTR)techniques.Experimental results have shown the performance improvement on the 20Newsgroup,Reuters Newswire and IMDB dataset.
文摘针对无人战斗机(unmanned combat air vehicle,UCAV)处于存在威胁区域的战场中路径规划问题,提出一种基于分组教与学算法的UCAV自适应路径规划方法。通过分析UCAV路径评价指标,提出一种自适应的UCAV路径评价模型,根据作战环境规划出距离短、威胁小的任务路径。针对教与学算法寻优精度低、耗时长的问题,提出一种分组教与学算法,引入动态分组和高斯分布扰动策略,提高算法寻优性能。通过仿真实验,该方案求解的最优路径更短且安全。
文摘为解决教与学优化算法容易早熟收敛的问题,在原算法的基础上提出一种基于混合策略改进的教与学优化算法(Mixed Strategy Based Improved Teaching-Learning Based Optimization,M-SITLBO)。首先,利用Logistic-Tent混沌映射策略初始化种群,保证种群的多样性;其次,在教师和学生阶段分别引入黄金正弦算法和基于莱维飞行与对数螺旋线的搜索策略优化个体的位置更新公式,增强并平衡算法的全局和局部收敛性能;最后,设计仿真对其寻优性能进行测试,结果表明改进后的教与学优化算法寻优速度、精度以及稳定性显著提升,且具有较强跳出局部最优的能力。
文摘针对舱段主动隔振系统中作动器配置优化问题,给出一种优化模型和方法,通过数值计算进行方法验证。首先建立了多通道舱段主动隔振系统的动力学模型,然后将作动器配置优化转换为约束0-1非线性规划问题,以系统监测点响应为优化目标函数,作动器启用状态为自变量,最后采用教与学优化(teaching and learning-based optimization,TLBO)算法寻找最优配置。仿真计算结果表明,对于不同的激励,多通道主动隔振系统的最优配置不同,即存在对应给定激励下抑制壳体振动与声辐射的最优配置。
