Accurate stereo vision calibration is a preliminary step towards high-precision visual posi- tioning of robot. Combining with the characteristics of genetic algorithm （GA） and particle swarm optimization （PSO）, a ...Accurate stereo vision calibration is a preliminary step towards high-precision visual posi- tioning of robot. Combining with the characteristics of genetic algorithm （GA） and particle swarm optimization （PSO）, a three-stage calibration method based on hybrid intelligent optimization is pro- posed for nonlinear camera models in this paper. The motivation is to improve the accuracy of the calibration process. In this approach, the stereo vision calibration is considered as an optimization problem that can be solved by the GA and PSO. The initial linear values can be obtained in the frost stage. Then in the second stage, two cameras＇ parameters are optimized separately. Finally, the in- tegrated optimized calibration of two models is obtained in the third stage. Direct linear transforma- tion （DLT）, GA and PSO are individually used in three stages. It is shown that the results of every stage can correctly find near-optimal solution and it can be used to initialize the next stage. Simula- tion analysis and actual experimental results indicate that this calibration method works more accu- rate and robust in noisy environment compared with traditional calibration methods. The proposed method can fulfill the requirements of robot sophisticated visual operation.展开更多
Twin support vector machine(TWSVM)is a new development of support vector machine(SVM)algorithm.It has the smaller computation scale and the stronger ability to cope with unbalanced problems.In this paper,TWSVM is intr...Twin support vector machine(TWSVM)is a new development of support vector machine(SVM)algorithm.It has the smaller computation scale and the stronger ability to cope with unbalanced problems.In this paper,TWSVM is introduced into aircraft engine gas path fault diagnosis.The generalization capacity of Gauss kernel function usually used in TWSVM is relatively weak.So a mixed kernel function is used to improve performance to ensure that the TWSVM algorithm can better balance a strong generalization ability and a good learning ability.Experimental results prove that the cross validation training accuracy of TWSVM using the mixed kernel function averagely increases 2%.Grid search is usually applied in parameter optimization of TWSVM,but it heavily depends on experience.Therefore,the hybrid particle swarm algorithm is introduced.It can intelligently and rapidly find the global optimum.Experiments prove that its training accuracy is better than that of the classical particle swarm algorithm by 5%.展开更多
计算密集型任务数量的增加导致智能移动设备(Smart Mobile Devices,SMD)计算任务过载,借助MEC(Mobile Edge Computing Servers)及利用网络中空闲边缘设备(Edge Devices,ED)可使计算能力受限的SMD将计算任务卸载到MEC和ED协作中,并基于...计算密集型任务数量的增加导致智能移动设备(Smart Mobile Devices,SMD)计算任务过载,借助MEC(Mobile Edge Computing Servers)及利用网络中空闲边缘设备(Edge Devices,ED)可使计算能力受限的SMD将计算任务卸载到MEC和ED协作中,并基于委托信誉证明(Delegated Proof of Reputation,DPoR)共识机制增强系统的安全性。文中提出一种基于鸟群人工鱼群算法(Bird Swarm-Artificial Fish Swarm Algorithm,BS-AFSA)的区块链移动边缘计算卸载模型,将任务卸载问题转化为优化目标函数来降低计算开销。采用改进鸟群人工鱼群算法来优化任务时延和能量消耗,对算法中的行为参数进行针对性构造,并改进拥挤度因子来提高后期迭代中寻优的局部搜索精度。仿真结果表明,与其他基准算法相比,文中所提算法减少了陷入局部最优的可能性,并降低了联合卸载方案的系统总开销。展开更多
鉴于实际生产中工人的能力和加工效率存在差异,本文提出了考虑工人差异性和刀具限制的多资源约束并行机分批调度问题,以最小化最大完工时间、最小化交付时间偏差为优化目标,构建了工人熟练度、刀具资源约束的混合整数线性规划模型,研究...鉴于实际生产中工人的能力和加工效率存在差异,本文提出了考虑工人差异性和刀具限制的多资源约束并行机分批调度问题,以最小化最大完工时间、最小化交付时间偏差为优化目标,构建了工人熟练度、刀具资源约束的混合整数线性规划模型,研究子批数量和大小、机器分配、工人分配、子批加工顺序之间的耦合关系,设计了一种改进的多目标混合灰狼-鲸鱼群算法(manyobjective hybrid grey wolf optimizer and whale swarm algorithm,MO-HGWSA).根据模型特点,设计了一种两阶段编码和解码方案表示问题的可行解;利用多种引导策略提高算法的进化效率;设计了局部搜索策略,增强算法的局部搜索能力.最后引入案例验证算法的有效性,结果表明本文所提算法在收敛性、分布性和解集支配关系方面均优于对比算法.展开更多
针对带时间窗的车辆路径问题(Vehicle Routing Problems with Time Windows,VRPTW),提出了一种混合粒子群优化算法(Hybrid Particle Swarm Optimization,HPSO)进行求解。所提出的算法设计了一种高效的编解码策略,以此搭建HPSO算法解空间...针对带时间窗的车辆路径问题(Vehicle Routing Problems with Time Windows,VRPTW),提出了一种混合粒子群优化算法(Hybrid Particle Swarm Optimization,HPSO)进行求解。所提出的算法设计了一种高效的编解码策略,以此搭建HPSO算法解空间到VRPTW解空间的桥梁。同时为了提高算法的寻优能力,设计了由单点插入策略以及双点交换策略组成的局部搜索策略。通过solomon-50标准数据集中的九个算例进行仿真实验,实验结果证明了所提出算法的寻优能力和稳定性均优于对比算法,最优解误差相较于对比算法最多降低了38.32%。展开更多
文摘Accurate stereo vision calibration is a preliminary step towards high-precision visual posi- tioning of robot. Combining with the characteristics of genetic algorithm （GA） and particle swarm optimization （PSO）, a three-stage calibration method based on hybrid intelligent optimization is pro- posed for nonlinear camera models in this paper. The motivation is to improve the accuracy of the calibration process. In this approach, the stereo vision calibration is considered as an optimization problem that can be solved by the GA and PSO. The initial linear values can be obtained in the frost stage. Then in the second stage, two cameras＇ parameters are optimized separately. Finally, the in- tegrated optimized calibration of two models is obtained in the third stage. Direct linear transforma- tion （DLT）, GA and PSO are individually used in three stages. It is shown that the results of every stage can correctly find near-optimal solution and it can be used to initialize the next stage. Simula- tion analysis and actual experimental results indicate that this calibration method works more accu- rate and robust in noisy environment compared with traditional calibration methods. The proposed method can fulfill the requirements of robot sophisticated visual operation.
基金supported by the Fundamental Research Funds for the Central Universities(No.NS2016027)
文摘Twin support vector machine(TWSVM)is a new development of support vector machine(SVM)algorithm.It has the smaller computation scale and the stronger ability to cope with unbalanced problems.In this paper,TWSVM is introduced into aircraft engine gas path fault diagnosis.The generalization capacity of Gauss kernel function usually used in TWSVM is relatively weak.So a mixed kernel function is used to improve performance to ensure that the TWSVM algorithm can better balance a strong generalization ability and a good learning ability.Experimental results prove that the cross validation training accuracy of TWSVM using the mixed kernel function averagely increases 2%.Grid search is usually applied in parameter optimization of TWSVM,but it heavily depends on experience.Therefore,the hybrid particle swarm algorithm is introduced.It can intelligently and rapidly find the global optimum.Experiments prove that its training accuracy is better than that of the classical particle swarm algorithm by 5%.
文摘计算密集型任务数量的增加导致智能移动设备(Smart Mobile Devices,SMD)计算任务过载,借助MEC(Mobile Edge Computing Servers)及利用网络中空闲边缘设备(Edge Devices,ED)可使计算能力受限的SMD将计算任务卸载到MEC和ED协作中,并基于委托信誉证明(Delegated Proof of Reputation,DPoR)共识机制增强系统的安全性。文中提出一种基于鸟群人工鱼群算法(Bird Swarm-Artificial Fish Swarm Algorithm,BS-AFSA)的区块链移动边缘计算卸载模型,将任务卸载问题转化为优化目标函数来降低计算开销。采用改进鸟群人工鱼群算法来优化任务时延和能量消耗,对算法中的行为参数进行针对性构造,并改进拥挤度因子来提高后期迭代中寻优的局部搜索精度。仿真结果表明,与其他基准算法相比,文中所提算法减少了陷入局部最优的可能性,并降低了联合卸载方案的系统总开销。
文摘鉴于实际生产中工人的能力和加工效率存在差异,本文提出了考虑工人差异性和刀具限制的多资源约束并行机分批调度问题,以最小化最大完工时间、最小化交付时间偏差为优化目标,构建了工人熟练度、刀具资源约束的混合整数线性规划模型,研究子批数量和大小、机器分配、工人分配、子批加工顺序之间的耦合关系,设计了一种改进的多目标混合灰狼-鲸鱼群算法(manyobjective hybrid grey wolf optimizer and whale swarm algorithm,MO-HGWSA).根据模型特点,设计了一种两阶段编码和解码方案表示问题的可行解;利用多种引导策略提高算法的进化效率;设计了局部搜索策略,增强算法的局部搜索能力.最后引入案例验证算法的有效性,结果表明本文所提算法在收敛性、分布性和解集支配关系方面均优于对比算法.
文摘针对带时间窗的车辆路径问题(Vehicle Routing Problems with Time Windows,VRPTW),提出了一种混合粒子群优化算法(Hybrid Particle Swarm Optimization,HPSO)进行求解。所提出的算法设计了一种高效的编解码策略,以此搭建HPSO算法解空间到VRPTW解空间的桥梁。同时为了提高算法的寻优能力,设计了由单点插入策略以及双点交换策略组成的局部搜索策略。通过solomon-50标准数据集中的九个算例进行仿真实验,实验结果证明了所提出算法的寻优能力和稳定性均优于对比算法,最优解误差相较于对比算法最多降低了38.32%。
