Quantitative algorithm for airborne gamma spectrum of large sample based on improved shuffled frog leaping-particle swarm optimization convolutional neural network

In airborne gamma ray spectrum processing,different analysis methods,technical requirements,analysis models,and calculation methods need to be established.To meet the engineering practice requirements of airborne gamma-ray measurements and improve computational efficiency,an improved shuffled frog leaping algorithm-particle swarm optimization convolutional neural network(SFLA-PSO CNN)for large-sample quantitative analysis of airborne gamma-ray spectra is proposed herein.This method was used to train the weight of the neural network,optimize the structure of the network,delete redundant connections,and enable the neural network to acquire the capability of quantitative spectrum processing.In full-spectrum data processing,this method can perform the functions of energy spectrum peak searching and peak area calculations.After network training,the mean SNR and RMSE of the spectral lines were 31.27 and 2.75,respectively,satisfying the demand for noise reduction.To test the processing ability of the algorithm in large samples of airborne gamma spectra,this study considered the measured data from the Saihangaobi survey area as an example to conduct data spectral analysis.The results show that calculation of the single-peak area takes only 0.13~0.15 ms,and the average relative errors of the peak area in the U,Th,and K spectra are 3.11,9.50,and 6.18%,indicating the high processing efficiency and accuracy of this algorithm.The performance of the model can be further improved by optimizing related parameters,but it can already meet the requirements of practical engineering measurement.This study provides a new idea for the full-spectrum processing of airborne gamma rays.

Optimization of Fairhurst-Cook Model for 2-D Wing Cracks Using Ant Colony Optimization (ACO), Particle Swarm Intelligence (PSO), and Genetic Algorithm (GA)

The common failure mechanism for brittle rocks is known to be axial splitting which happens parallel to the direction of maximum compression. One of the mechanisms proposed for modelling of axial splitting is the sliding crack or so called, “wing crack” model. Fairhurst-Cook model explains this specific type of failure which starts by a pre-crack and finally breaks the rock by propagating 2-D cracks under uniaxial compression. In this paper, optimization of this model has been considered and the process has been done by a complete sensitivity analysis on the main parameters of the model and excluding the trends of their changes and also their limits and “peak points”. Later on this paper, three artificial intelligence algorithms including Particle Swarm Intelligence (PSO), Ant Colony Optimization (ACO) and genetic algorithm (GA) has been used and compared in order to achieve optimized sets of parameters resulting in near-maximum or near-minimum amounts of wedging forces creating a wing crack.

UAV penetration mission path planning based on improved holonic particle swarm optimization

To meet the requirements of safety, concealment, and timeliness of trajectory planning during the unmanned aerial vehicle(UAV) penetration process, a three-dimensional path planning algorithm is proposed based on improved holonic particle swarm optimization(IHPSO). Firstly, the requirements of terrain threat, radar detection, and penetration time in the process of UAV penetration are quantified. Regarding radar threats, a radar echo analysis method based on radar cross section(RCS)and the spatial situation is proposed to quantify the concealment of UAV penetration. Then the structure-particle swarm optimization(PSO) algorithm is improved from three aspects.First, the conversion ability of the search strategy is enhanced by using the system clustering method and the information entropy grouping strategy instead of random grouping and constructing the state switching conditions based on the fitness function.Second, the unclear setting of iteration numbers is addressed by using particle spacing to create the termination condition of the algorithm. Finally, the trajectory is optimized to meet the intended requirements by building a predictive control model and using the IHPSO for simulation verification. Numerical examples show the superiority of the proposed method over the existing PSO methods.

Neural network hyperparameter optimization based on improved particle swarm optimization

Hyperparameter optimization is considered as one of the most challenges in deep learning and dominates the precision of model in a certain.Recent proposals tried to solve this issue through the particle swarm optimization(PSO),but its native defect may result in the local optima trapped and convergence difficulty.In this paper,the genetic operations are introduced to the PSO,which makes the best hyperparameter combination scheme for specific network architecture be located easier.Spe-cifically,to prevent the troubles caused by the different data types and value scopes,a mixed coding method is used to ensure the effectiveness of particles.Moreover,the crossover and mutation opera-tions are added to the process of particles updating,to increase the diversity of particles and avoid local optima in searching.Verified with three benchmark datasets,MNIST,Fashion-MNIST,and CIFAR10,it is demonstrated that the proposed scheme can achieve accuracies of 99.58%,93.39%,and 78.96%,respectively,improving the accuracy by about 0.1%,0.5%,and 2%,respectively,compared with that of the PSO.

Particle swarm optimization-based algorithm of a symplectic method for robotic dynamics and control

Multibody system dynamics provides a strong tool for the estimation of dynamic performances and the optimization of multisystem robot design. It can be described with differential algebraic equations(DAEs). In this paper, a particle swarm optimization(PSO) method is introduced to solve and control a symplectic multibody system for the first time. It is first combined with the symplectic method to solve problems in uncontrolled and controlled robotic arm systems. It is shown that the results conserve the energy and keep the constraints of the chaotic motion, which demonstrates the efficiency, accuracy, and time-saving ability of the method. To make the system move along the pre-planned path, which is a functional extremum problem, a double-PSO-based instantaneous optimal control is introduced. Examples are performed to test the effectiveness of the double-PSO-based instantaneous optimal control. The results show that the method has high accuracy, a fast convergence speed, and a wide range of applications.All the above verify the immense potential applications of the PSO method in multibody system dynamics.

Genetic algorithm and particle swarm optimization tuned fuzzy PID controller on direct torque control of dual star induction motor

This study presents analysis, control and comparison of three hybrid approaches for the direct torque control (DTC) of the dual star induction motor (DSIM) drive. Its objective consists of combining three different heuristic optimization techniques including PID-PSO, Fuzzy-PSO and GA-PSO to improve the DSIM speed controlled loop behavior. The GA and PSO algorithms are developed and implemented into MATLAB. As a result, fuzzy-PSO is the most appropriate scheme. The main performance of fuzzy-PSO is reducing high torque ripples, improving rise time and avoiding disturbances that affect the drive performance.

Shaping the Wavefront of Incident Light with a Strong Robustness Particle Swarm Optimization Algorithm

We demonstrate a modified particle swarm optimization(PSO) algorithm to effectively shape the incident light with strong robustness and short optimization time. The performance of the modified PSO algorithm and genetic algorithm(GA) is numerically simulated. Then, using a high speed digital micromirror device, we carry out light focusing experiments with the modified PSO algorithm and GA. The experimental results show that the modified PSO algorithm has greater robustness and faster convergence speed than GA. This modified PSO algorithm has great application prospects in optical focusing and imaging inside in vivo biological tissue, which possesses a complicated background.

Robot stereo vision calibration method with genetic algorithm and particle swarm optimization

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.

基于PSO-Elman神经网络的井底风温预测模型

目前井下风温预测大多采用BP神经网络,但其预测精度受学习样本数量的影响,且容易陷入局部最优,Elman神经网络具备局部记忆能力,提高了网络的稳定性和动态适应能力,但仍然存在收敛速度过慢、易陷入局部最优的问题。针对上述问题,采用粒子群优化(PSO)算法对Elman神经网络的权值和阈值进行优化,建立了基于PSO-Elman神经网络的井底风温预测模型。分析得出入风相对湿度、入风温度、地面大气压力和井筒深度是井底风温的主要影响因素,因此将其作为模型的输入数据,模型的输出数据为井底风温。在相同样本数据集下的实验结果表明:Elman模型迭代90次后收敛,PSO-Elman模型迭代41次后收敛,说明PSO-Elman模型收敛速度更快;与BP神经网络模型、支持向量回归模型和Elman模型相比,PSO-Elman模型的预测误差较低,平均绝对误差、均方误差(MSE)、平均绝对百分比误差分别为0.376 0℃,0.278 3,1.95%,决定系数R^(2)为0.992 4,非常接近1,表明预测模型具有良好的预测效果。实例验证结果表明,PSO-Elman模型的相对误差范围为-4.69%~1.27%,绝对误差范围为-1.06~0.29℃,MSE为0.26,整体预测精度可满足井下实际需要。

基于PSO-SVM的Φ-OTDR系统模式识别研究

针对相位敏感光时域反射仪(phase sensitive optical time domain reflectometer,Φ-OTDR)系统中误报率高的问题,提出一种多域特征提取与粒子群算法优化支持向量机(particle swarm optimization-support vector machine,PSO-SVM)相结合的模式识别算法。首先,对原始信号进行差分处理后提取时域特征,并利用小波包分解方法,通过验证不同分解层数下的事件分类准确率,设定最优分解层数为6层,提取差分信号的能量特征。然后以SVM分类器为基础,利用PSO算法优化SVM分类器参数,提高光纤振动信号识别准确率。最后利用Φ-OTDR事件数据集进行验证,实验结果表明,该模式识别算法达到了95.6%的振动事件分类准确率。

基于GA-PSO算法的冻土本构模型参数识别

遗传算法(GA)与粒子群算法(PSO)分别具有缺乏目标导向性和易陷入局部最优的缺点,但同时分别具有全局搜索能力强与能有效传递优势信息的优点。本文以GA计算步结合精英保留策略作为PSO计算步的优势信息,避免PSO算法陷入局部最优,以PSO计算步结合非精英优化策略作为GA计算步的导向信息,克服GA算法缺乏目标导向的问题,建立了GA-PSO新算法。其具体过程为,通过采用GA计算步对解空间进行全局搜索并对精英个体进行保留,进一步,将适应度较差的个体利用PSO计算步进行优化。基于多峰函数的验证结果表明,GA-PSO算法在解空间中具有更强的全局搜索能力,同时具有更快的收敛速度。将GA-PSO算法应用到冻土非正交弹塑性本构模型的参数识别中,通过模型的参数识别以及模型预测结果对比与验证,结果表明GA-PSO算法能够有效识别冻土非正交弹塑性本构模型的参数,提升了模型的预测效果。

基于PSO-GA的分片区块链系统性能优化方法

在这篇文章中,针对分片区块链(Sharded Blockchain)系统性能优化问题,提出了一种结合粒子群和遗传算法的系统性能优化方法(PSO-GA),目的是为了在尽可能满足当前网络环境情况下,提升其系统吞吐量.该方法考虑分片区块链中节点的计算能力、恶意节点的概率以及节点之间的传输速率等不同网络环境下,找到响应网络状态的最佳分片区块链系统参数;为了避免传统粒子群优化算法陷入局部最优的问题,引入遗传算法中的交叉操作和变异操作,有效提高方法的准确性.通过大量仿真实验对方法的有效性进行验证分析.实验结果表明,相比于其他的方法,本文所提出的方法可以在更短的时间取得更高的系统吞吐量.

基于AG-MOPSO的含风电配电网无功优化

针对风电机组并网出力的不确定性,采用基于概率发生的场景分析法将不确定性模型转换为不同发生概率的多场景问题,建立以有功网损和电压偏差最小为目标的无功优化模型。针对传统方法得到的Pareto前沿多样性较差的问题,提出基于自适应网格的多目标粒子群优化AG-MOPSO(adaptive grid multi-objective particle swarm optimization)算法。该算法采用自适应网格得到外部档案库中粒子的密度,并根据密度信息以轮盘赌机制选取全局最优粒子和维护外部存储库的规模,有效地保证了Pareto前沿分布的均匀性和多样性。运用该算法对含风电的IEEE 33节点系统进行无功优化计算,并与已有NSGA-Ⅱ算法进行比较,结果表明所提算法得到的Pareto前沿较好,验证了该模型和算法的可行性。

Bacterial graphical user interface oriented by particle swarm optimization strategy for optimization of multiple type DFACTS for power quality enhancement in distribution system

This study proposes a graphical user interface(GUI) based on an enhanced bacterial foraging optimization(EBFO) to find the optimal locations and sizing parameters of multi-type DFACTS in large-scale distribution systems.The proposed GUI based toolbox,allows the user to choose between single and multiple DFACTS allocations,followed by the type and number of them to be allocated.The EBFO is then applied to obtain optimal locations and ratings of the single and multiple DFACTS.This is found to be faster and provides more accurate results compared to the usual PSO and BFO.Results obtained with MATLAB/Simulink simulations are compared with PSO,BFO and enhanced BFO.It reveals that enhanced BFO shows quick convergence to reach the desired solution there by yielding superior solution quality.Simulation results concluded that the EBFO based multiple DFACTS allocation using DSSSC,APC and DSTATCOM is preferable to reduce power losses,improve load balancing and enhance voltage deviation index to 70%,38% and 132% respectively and also it can improve loading factor without additional power loss.

基于GA/PSO BP神经网络的石家庄VOCs环境浓度预测模型研究

为了提升挥发性有机物(Volatile Organic Components,VOCs)的预测精度,在反向传播(Back Propagation,BP)网络结构的基础上使用优化算法分别为遗传算法(Genetic Algorithms,GA)优化BP神经网络(GA BP)和粒子群算法(Particle Swarm Optimization,PSO)优化BP神经网络(PSO BP)对VOCs质量浓度进行预测。首先,对污染物及气象因子进行筛选。采用相关性分析法及逐步回归法进行分析筛选,并筛选出合适的输入变量。其次,建立BP神经网络结构。利用BP、GA BP、PSO BP神经网络,以石家庄市2022年夏季污染数据为样本对VOCs质量浓度进行预测。结果显示,经相关性分析及逐步回归法筛选,将PM_(2.5)质量浓度、O_(3)质量浓度、NO_(2)质量浓度、温度、相对湿度作为输入变量。经预测结果对比,PSO BP神经网络模型的预测精度较高,烷烃、烯烃、芳香烃和含氧烃实测值与预测值之间的拟合程度(R^(2))分别为0.80、0.55、0.78、0.67。研究结果可为日后VOCs污染预报预警提供理论参考。

求解全局优化问题的SCA-VPPSO算法及其应用

正余弦算法和速度暂停粒子群算法是两个优秀的元启发式算法,用于解决连续全局优化问题。在解决实际问题中,它们始终面临着跳出局部极小的问题。为此,基于二者,提出了一种新的混合搜索算法,称为SCA-VPPSO算法。该算法以速度暂停粒子群算法的搜索框架为基础,将正余弦搜索算子从原先的全维度更新策略转变为部分维度更新策略,并将之用于开发探索上,与速度暂停粒子群算法中的局部搜索行为进行了融合,形成双模式局部探索模式。混合后的SCA-VPPSO算法能够更加有效地平衡局部利用和全局探索,从而增强算法跳出局部最小的能力并获得更好的结果。所提算法与正余弦算法、速度暂停粒子群算法和2个近期发表的优秀算法在CEC2019测试集和一个工程实际应用上进行了性能分析,结果表明所提算法的优化性能有显著提高,扩展了算法的应用范围,为元启发式算法的发展提供了新的混合搜索模式。

基于GWO-PSO算法的堆垛机混合作业优化研究

为减少堆垛机执行混合作业的运行时间,建立堆垛机运行时间最小的数学模型,并提出一种改进的GWO-PSO算法进行求解。首先,在初始化阶段,将灰狼个体随机分为若干群组,按照标准GWO算法进行独立寻优,推举产生首领狼王,然后采用PSO算法的位置更新方式对寻优结果进行更新,保证了种群的多样性和算法的寻优速度,接着引入速度交换算子进行离散化处理,并通过设置阈值解决了算法易陷入局部最优的问题,最后通过实例仿真分析,验证了GWO-PSO算法的有效性。

基于PSO-BP-UKF算法的锂电池SOC估计方法研究

锂电池的荷电状态(SOC)是锂电池质量管理的核心之一。基于有效的SOC估计是确保锂电池安全高效工作的必要条件,提出一种利用粒子群算法(PSO)优化反向传播(BP)神经网络,并将优化后的BP神经网络SOC输出值作为无迹卡尔曼滤波(UKF)观测值的锂电池SOC估计方法。使用来自马里兰大学的FUDS工况电池测试数据,将所提的PSO-BP-UKF算法与GA-BP-UKF算法、BP算法进行对比。结果表明,在25℃环境下,PSO-BP-UKF算法的最大偏差<3.17%,平均误差<6.44%,均方根偏差<0.0025,相比GA-BP-UKF算法和BP方法都有较大幅度的提高,说明所提算法具备有效性与实用性。

改进PSO-BP算法的短期电力负荷预测方法

针对电力负荷的周期性、随机波动性等复杂特点易造成预测精度低等问题,提出一种基于相似日分析、混沌映射优化粒子群算法(particle swarm optimization,PSO)和BP神经网络相结合的短期电力负荷预测方法。采用乘积法量化气象因素与时间因素间的综合相似度,选出综合相似度高的若干历史日作为相似日集;采用相似日集与非相似日集分别训练PSO-BP模型,相似日集的平均绝对百分比误差(mean absolute percentage error,MAPE)降低3.9%;利用Sine映射对PSO中粒子的速度和位置进行优化,增强PSO算法的全局搜索能力和寻优精度,采用2个集合分别训练SPSO-BP模型,相似日集的MAPE降低19.4%。结果表明,基于相似日分析和SPSO-BP模型的短期电力负荷预测方法可有效提高电力负荷的预测精度。

Particle Swarm Optimization Applied to Some Anti-Windup Problems

The particle swarm optimization (PSO) algorithm is introduced to deal with some open anti-windup problems, i.e., determining the initial condition when applying the iterative algorithm to enlarge the estimate of the domain of attraction, determining the design point in the delayed anti-windup scheme, and determining the design point and the weighting factors in the multi-stage anti-windup scheme. Therefore, the corresponding PSO-based algorithms are proposed. Unlike the traditional methods in which the free design parameters can only be selected by trial and error with the available computational results, the PSO-based algorithms provide a systematic way to determine these parameters. In addition, the algorithms are easy to be implemented and are very likely to find the desirable parameters that further improve the anti-windup closed-loop performances. Simulation results are presented to validate the effectiveness and advantages of the proposed method.