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Derivative Free and Dispatch Algorithm-Based Optimization and Power System Assessment of a Biomass-PV-Hydrogen Storage-Grid Hybrid Renewable Microgrid for Agricultural Applications
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作者 Md.Fatin Ishraque Akhlaqur Rahman +5 位作者 Kamil Ahmad Sk.A.Shezan Md.Meheraf Hossain Sheikh Rashel Al Ahmed Md.Iasir Arafat Noor E Nahid Bintu 《Energy Engineering》 2025年第8期3347-3375,共29页
In this research work,the localized generation from renewable resources and the distribution of energy to agricultural loads,which is a local microgrid concept,have been considered,and its feasibility has been assesse... In this research work,the localized generation from renewable resources and the distribution of energy to agricultural loads,which is a local microgrid concept,have been considered,and its feasibility has been assessed.Two dispatch algorithms,named Cycle Charging and Load Following,are implemented to find the optimal solution(i.e.,net cost,operation cost,carbon emission.energy cost,component sizing,etc.)of the hybrid system.The microgrid is also modeled in the DIgSILENT Power Factory platform,and the respective power system responses are then evaluated.The development of dispatch algorithms specifically tailored for agricultural applications has enabled to dynamically manage energy flows,responding to fluctuating demands and resource availability in real-time.Through careful consideration of factors such as seasonal variations and irrigation requirements,these algorithms have enhanced the resilience and adaptability of the microgrid to dynamic operational conditions.However,it is revealed that both approaches have produced the same techno-economic results showing no significant difference.This illustrates the fact that the considered microgrid can be implemented with either strategy without significant fluctuation in performance.The study has shown that the harmful gas emission has also been limited to only 17,928 kg/year of CO_(2),and 77.7 kg/year of Sulfur Dioxide.For the proposed microgrid and load profile of 165.29 kWh/day,the net present cost is USD 718,279,and the cost of energy is USD 0.0463 with a renewable fraction of 97.6%.The optimal sizes for PV,Bio,Grid,Electrolyzer,and Converter are 1494,500,999,999,500,and 495 kW,respectively.For a hydrogen tank(HTank),the optimal size is found to be 350 kg.This research work provides critical insights into the techno-economic feasibility and environmental impact of integrating biomass-PV-hydrogen storage-Grid hybrid renewable microgrids into agricultural settings. 展开更多
关键词 Renewable energy derivative-free algorithm OPTIMIZATION hybrid system energy storage
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Research on three-dimensional attack area based on improved backtracking and ALPS-GP algorithms of air-to-air missile
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作者 ZHANG Haodi WANG Yuhui HE Jiale 《Journal of Systems Engineering and Electronics》 2025年第1期292-310,共19页
In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of t... In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of the three-dimensional attack area model,restrict their practical applications.To address these issues,an improved backtracking algorithm is proposed to improve calculation efficiency.A significant reduction in solution time and maintenance of accuracy in the three-dimensional attack area are achieved by using the proposed algorithm.Furthermore,the age-layered population structure genetic programming(ALPS-GP)algorithm is introduced to determine an analytical polynomial model of the three-dimensional attack area,considering real-time requirements.The accuracy of the polynomial model is enhanced through the coefficient correction using an improved gradient descent algorithm.The study reveals a remarkable combination of high accuracy and efficient real-time computation,with a mean error of 91.89 m using the analytical polynomial model of the three-dimensional attack area solved in just 10^(-4)s,thus meeting the requirements of real-time combat scenarios. 展开更多
关键词 air combat three-dimensional attack area improved backtracking algorithm age-layered population structure genetic programming(ALPS-GP) gradient descent algorithm
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解决非线性互补问题的Derivative-Free算法 被引量:4
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作者 蒋利华 徐安农 《安徽大学学报(自然科学版)》 CAS 北大核心 2007年第4期17-21,共5页
基于NCP(F)的约束极小化变形,构造了一种新的merit函数,将原始的NCP(F)问题转化为约束极小化问题,并构造了相应的derivative-free下降算法,并在merit函数严格单调的条件下证明了derivative-free算法的合理性以及整体收敛性.
关键词 非线性互补问题(NCP(F)) merit函数 derivative-free下降算法 整体收敛性
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一种新的求解非线性互补问题的Derivative-Free算法 被引量:2
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作者 蒋利华 刘丽华 《安徽理工大学学报(自然科学版)》 CAS 2006年第3期81-84,共4页
把NCP(F)通过约束极小化变形转化为无约束极小化问题,构造一种新的D eriva-tive-F ree下降算法,并在一定条件下证明了D erivative-F ree下降算法的合理性及整体收敛性。
关键词 非线性互补问题(NCP(F)) derivative-free下降算法 整体收敛性
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非线性互补问题的Derivative-Free下降方法 被引量:1
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作者 蒋利华 马昌凤 徐安农 《广西科学》 CAS 2006年第3期190-193,共4页
基于非线性互补问题(N CP(F))的约束极小化变形,构造一种新的m erit函数,将原始的N CP(F)问题转化为约束极小化问题,构造相应的derivative-free下降算法.在m erit函数严格单调的条件下证明derivative-free下降算法的合理性以及整体收敛性.
关键词 非线性互补问题 merit函数 derivative-free 下降算法 整体收敛性
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The Convergence of the Steepest Descent Algorithm for D.C.Optimization 被引量:1
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作者 SONG Chun-ling XIA Zun-quan 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期131-136,共6页
Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and c... Some properties of a class of quasi-differentiable functions(the difference of two finite convex functions) are considered in this paper. And the convergence of the steepest descent algorithm for unconstrained and constrained quasi-differentiable programming is proved. 展开更多
关键词 nonsmooth optimization D. C. optimization upper semi-continuous lower semi-continuous steepest descent algorithm CONVERGENCE
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Channel estimation for MIMO-OFDM systems using steepest-descent algorithm 被引量:1
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作者 L UXin XU Jun 《通讯和计算机(中英文版)》 2009年第11期64-68,共5页
关键词 最速下降算法 信道估计 OFDM系统 MIMO 快衰落信道 最速下降法 估计方法 分配模式
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Merit functions for nonsmooth complementarity problems and related descent algorithm
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作者 DU Shou-qiang GAO Yan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第1期78-84,共7页
Under some assumptions, the solution set of a nonlinear complementarity problem coincides with the set of local minima of the corresponding minimization problem. This paper uses a family of new merit functions to deal... Under some assumptions, the solution set of a nonlinear complementarity problem coincides with the set of local minima of the corresponding minimization problem. This paper uses a family of new merit functions to deal with nonlinear complementarity problem where the underlying function is assumed to be a continuous but not necessarily locally Lipschitzian map and gives a descent algorithm for solving the nonsmooth continuous complementarity problems. In addition, the global convergence of the derivative free descent algorithm is also proved. 展开更多
关键词 Nonsmooth complementarity problem merit function nonsmooth continuous map descent algorithm.
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Gradient Descent Algorithm for Small UAV Parameter Estimation System
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作者 Guo Jiandong Liu Qingwen Wang Kang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期680-687,共8页
A gradient descent algorithm with adjustable parameter for attitude estimation is developed,aiming at the attitude measurement for small unmanned aerial vehicle(UAV)in real-time flight conditions.The accelerometer and... A gradient descent algorithm with adjustable parameter for attitude estimation is developed,aiming at the attitude measurement for small unmanned aerial vehicle(UAV)in real-time flight conditions.The accelerometer and magnetometer are introduced to construct an error equation with the gyros,thus the drifting characteristics of gyroscope can be compensated by solving the error equation utilized by the gradient descent algorithm.Performance of the presented algorithm is evaluated using a self-proposed micro-electro-mechanical system(MEMS)based attitude heading reference system which is mounted on a tri-axis turntable.The on-ground,turntable and flight experiments indicate that the estimation attitude has a good accuracy.Also,the presented system is compared with an open-source flight control system which runs extended Kalman filter(EKF),and the results show that the attitude control system using the gradient descent method can estimate the attitudes for UAV effectively. 展开更多
关键词 gradient descent algorithm attitude estimation QUATERNIONS small unmanned aerial vehicle(UAV)
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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs
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作者 Lianghao Hua Jianfeng Zhang +1 位作者 Dejie Li Xiaobo Xi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2129-2157,共29页
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej... With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance. 展开更多
关键词 Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm
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基于BPNN-EKF-GD-RF算法的锂离子电池组荷电状态估计方法
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作者 来鑫 翁嘉辉 +4 位作者 杨一鹏 孙宇飞 周龙 郑岳久 韩雪冰 《机械工程学报》 北大核心 2025年第12期251-265,共15页
锂离子电池模组的荷电状态估计(State-of-charge, SOC)是影响电池性能的一个重要内部状态,是电池组进行其它状态估计的基础。然而它的估计准确性易受温度等外部因素影响,且电池间的不一致性也为电池组中各单体电池的SOC估计带来了困难... 锂离子电池模组的荷电状态估计(State-of-charge, SOC)是影响电池性能的一个重要内部状态,是电池组进行其它状态估计的基础。然而它的估计准确性易受温度等外部因素影响,且电池间的不一致性也为电池组中各单体电池的SOC估计带来了困难。提出一种将BP神经网络(Back propagation neural network, BPNN)与扩展卡尔曼滤波(Extended Kalman filter, EKF)算法相结合的电池组SOC估计方法。该方法首先基于先验SOC利用BPNN估计不同温度下“领导者”电池的端电压,将其与实测端电压对比后采用EKF算法完成SOC后验估计,同时基于电压差采用梯度下降(Gradient descent, GD)算法更新BPNN的输出层权重使算法更快收敛。在此基础上,设计修正策略利用随机森林(Random forest, RF)算法对“跟随者”电池的SOC进行调整估计。试验结果表明,所提的BPNN-EKF-GD-RF算法能实现电池组在不同温度下SOC的准确估计,常温下SOC估计误差保持在2.5%以内,在温度变化下电池组中单体电池SOC估计最大误差不超过3.2%,为复杂环境下锂离子电池组的SOC估计提供了一种高精度低复杂度方案。 展开更多
关键词 SOC估计 BP神经网络 扩展卡尔曼滤波 梯度下降算法 随机森林 锂离子电池组
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繁忙终端区连续下降运行的4D轨迹预测
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作者 王超 陈含露 +1 位作者 秦宏坤 刘博 《西南交通大学学报》 北大核心 2025年第3期722-730,共9页
为在繁忙终端区实施连续下降运行(CDO)并估算其二氧化碳减排成效,提出一种基于数据驱动和最优控制理论相结合的连续下降运行4D轨迹预测方法.首先,通过近邻传播轨迹聚类方法对典型进场水平路径进行识别;然后,以典型进场水平路径为依据,... 为在繁忙终端区实施连续下降运行(CDO)并估算其二氧化碳减排成效,提出一种基于数据驱动和最优控制理论相结合的连续下降运行4D轨迹预测方法.首先,通过近邻传播轨迹聚类方法对典型进场水平路径进行识别;然后,以典型进场水平路径为依据,分别以最小时间和最小燃油为目标,建立垂直剖面连续下降运行多阶段最优控制模型,并提出一种基于遗传算法的最优控制模型求解新方法(GACDO);最后,利用终端区实际轨迹数据,开展典型进场水平路径识别和连续下降运行模式下的4D轨迹预测与减排收益比较实验.结果表明:该方法能获得理想的连续下降运行4D轨迹;以最小时间为优化目标时,平均运行时间和二氧化碳排放分别减少26%和8%;以最小油耗为优化目标时,运行时间和二氧化碳排放分别减少17%和20%. 展开更多
关键词 4D轨迹预测 连续下降运行 遗传算法 轨迹聚类 最优控制
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天津汉1流体观测井水温畸变的自主识别与映震效能分析
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作者 许贺 张明东 +1 位作者 王熠熙 李悦 《地震地磁观测与研究》 2025年第3期88-95,共8页
采用差分连降算法,自主识别并提取2015—2021年天津汉1流体观测井水温畸变数据,以研究时段内井孔周边200 km范围内M_(S)≥3.4典型震例作为研究对象,从频次累和、幅度累和、时间累和3个方面展开分析,检验不同阈值下不同预报期的地震预报... 采用差分连降算法,自主识别并提取2015—2021年天津汉1流体观测井水温畸变数据,以研究时段内井孔周边200 km范围内M_(S)≥3.4典型震例作为研究对象,从频次累和、幅度累和、时间累和3个方面展开分析,检验不同阈值下不同预报期的地震预报效能,结果认为:①频次累和最优预报条件:频次阈值为13,预报期为89天,增益概率与R值达最高;②幅度累和最优预报条件:幅度累和超过0.0231℃,预报期为61天,增益概率和R值达最高;③时间累和最优预报条件:每日畸变时间累和超过80 min,预报期为89天,增益概率和R值达最高。在3种异常判定条件中,幅度累和效果最佳,时间累和次之,频次累和效果相对较弱。 展开更多
关键词 差分连降算法 水温畸变 自主识别 预报效能
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基于神经网络的船舶辐射噪声预报方法 被引量:2
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作者 黄欣 徐荣武 李瑞彪 《船舶力学》 北大核心 2025年第3期486-496,共11页
针对船舶机械设备众多、结构复杂、振动传递路径相互耦合的现状,本文提出基于误差反向传播(Back Propagation, BP)神经网络的船舶水下辐射噪声预报方法。分别构建基于梯度下降算法和贝叶斯正则化算法的BP神经网络,以振动数据为输入量、... 针对船舶机械设备众多、结构复杂、振动传递路径相互耦合的现状,本文提出基于误差反向传播(Back Propagation, BP)神经网络的船舶水下辐射噪声预报方法。分别构建基于梯度下降算法和贝叶斯正则化算法的BP神经网络,以振动数据为输入量、船体辐射噪声为输出量,将均方根误差(e RMSE)和平均绝对误差(e MAE)作为模型预测精度评价指标。结果表明,贝叶斯正则化BP神经网络的泛化性和鲁棒性优于梯度下降算法的BP神经网络,误差达到3 dB以内,在船舶辐射噪声预报领域具有较好的适用性。 展开更多
关键词 辐射噪声预报 BP神经网络 梯度下降算法 贝叶斯正则化算法
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基于压缩感知稀疏域模型并行坐标下降算法的DOA估计方法
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作者 王宏妍 白艳萍 +2 位作者 郑文康 王立府 续婷 《吉林大学学报(理学版)》 北大核心 2025年第3期924-933,共10页
针对现有的波达方向(direction of arrival,DOA)估计方法在低信噪比、小快拍、多信源条件下估计精度较低的问题,提出一种基于并行坐标下降算法的DOA估计方法.首先,对空域等角度均匀划分,构造超完备冗余字典;其次,采用并行坐标下降算法... 针对现有的波达方向(direction of arrival,DOA)估计方法在低信噪比、小快拍、多信源条件下估计精度较低的问题,提出一种基于并行坐标下降算法的DOA估计方法.首先,对空域等角度均匀划分,构造超完备冗余字典;其次,采用并行坐标下降算法的思想对稀疏信号进行重构,得到信号在空域的稀疏系数矩阵;最后,将稀疏矩阵行向量的l2-范数映射到空域网格上,得到准确的DOA估计值.仿真实验结果表明:在低信噪比、小快拍、多信源条件下,该方法优于子空间类算法、贪婪类算法以及凸优化类算法,具有更低的均方根误差(RMSE)、更高的DOA估计精度和运行效率. 展开更多
关键词 波达方向估计 压缩感知 并行坐标下降算法 矢量水听器阵列信号
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具有多型避障方式的智能车辆路径规划 被引量:2
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作者 胡子牛 陈鑫鹏 +3 位作者 杨泽宇 余子云 秦洪懋 高铭 《汽车工程》 北大核心 2025年第3期402-411,共10页
非结构化场景往往存在多种尺寸各异的障碍物,路径规划过程只考虑绕行的避障方式会导致车辆通行效率降低。针对该问题,本文在传统混合A^(*)算法中融合分层碰撞检测策略,提出了一种具有多型避障方式的智能车辆路径规划方法。首先,以车辆... 非结构化场景往往存在多种尺寸各异的障碍物,路径规划过程只考虑绕行的避障方式会导致车辆通行效率降低。针对该问题,本文在传统混合A^(*)算法中融合分层碰撞检测策略,提出了一种具有多型避障方式的智能车辆路径规划方法。首先,以车辆底盘高度为基准构造上下双层栅格地图,并利用车身轮廓和四轮轮廓设计分层碰撞检测策略;然后,通过合理设计的启发函数与代价函数计算方式,使得混合A^(*)算法能够在多障碍物场景中高效搜索路径;最后,利用梯度下降法对路径进行平滑优化。仿真与实车试验结果表明,所提出算法可有效提高路径搜索效率并改善路径平滑性,且规划路径兼顾了跨障与绕障方式,使得车辆在多障碍物场景下具备更良好的通过性。 展开更多
关键词 路径规划 混合A*算法 分层碰撞检测策略 梯度下降法
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A survey on multi-objective,model-based,oil and gas field development optimization:Current status and future directions 被引量:1
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作者 Auref Rostamian Matheus Bernardelli de Moraes +1 位作者 Denis Jose Schiozer Guilherme Palermo Coelho 《Petroleum Science》 2025年第1期508-526,共19页
In the area of reservoir engineering,the optimization of oil and gas production is a complex task involving a myriad of interconnected decision variables shaping the production system's infrastructure.Traditionall... In the area of reservoir engineering,the optimization of oil and gas production is a complex task involving a myriad of interconnected decision variables shaping the production system's infrastructure.Traditionally,this optimization process was centered on a single objective,such as net present value,return on investment,cumulative oil production,or cumulative water production.However,the inherent complexity of reservoir exploration necessitates a departure from this single-objective approach.Mul-tiple conflicting production and economic indicators must now be considered to enable more precise and robust decision-making.In response to this challenge,researchers have embarked on a journey to explore field development optimization of multiple conflicting criteria,employing the formidable tools of multi-objective optimization algorithms.These algorithms delve into the intricate terrain of production strategy design,seeking to strike a delicate balance between the often-contrasting objectives.Over the years,a plethora of these algorithms have emerged,ranging from a priori methods to a posteriori approach,each offering unique insights and capabilities.This survey endeavors to encapsulate,catego-rize,and scrutinize these invaluable contributions to field development optimization,which grapple with the complexities of multiple conflicting objective functions.Beyond the overview of existing methodologies,we delve into the persisting challenges faced by researchers and practitioners alike.Notably,the application of multi-objective optimization techniques to production optimization is hin-dered by the resource-intensive nature of reservoir simulation,especially when confronted with inherent uncertainties.As a result of this survey,emerging opportunities have been identified that will serve as catalysts for pivotal research endeavors in the future.As intelligent and more efficient algo-rithms continue to evolve,the potential for addressing hitherto insurmountable field development optimization obstacles becomes increasingly viable.This discussion on future prospects aims to inspire critical research,guiding the way toward innovative solutions in the ever-evolving landscape of oil and gas production optimization. 展开更多
关键词 derivative-free algorithms Ensemble-based optimization Gradient-based methods Life-cycle optimization Reservoir field development and management
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考虑岩层倾角-围压组合效应的岩石强度行为初探
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作者 罗斌玉 苏辕 +4 位作者 刘晓云 黄腾达 肖枫亦 刘兰心 李鹏程 《岩土力学》 北大核心 2025年第3期775-788,共14页
研究岩石强度行为的岩层倾角-围压组合效应是揭示充填体约束缓倾斜矿柱强度行为的基础。采用数值模拟代替围压下的岩石倾斜加载试验,研究倾角-围压下岩石剪切破坏规律和强度特征。以红砂岩为研究对象,开展红砂岩单轴和剪切试验,获得红... 研究岩石强度行为的岩层倾角-围压组合效应是揭示充填体约束缓倾斜矿柱强度行为的基础。采用数值模拟代替围压下的岩石倾斜加载试验,研究倾角-围压下岩石剪切破坏规律和强度特征。以红砂岩为研究对象,开展红砂岩单轴和剪切试验,获得红砂岩的基本力学参数。以校核过的红砂岩基本力学参数为基础,开展7种倾角6种围压组合的岩石倾斜加载数值模拟,获取倾角-围压下岩石剪切破坏规律和强度特征。结果显示,随着倾角的增大,剪切带与水平面的倾角越大,且围压越大,剪切带变厚;增大围压能有效降低倾角对岩石强度的影响。然后利用非常规应力圆表征极限状态下岩石应力状态的围压-倾角效应,随着倾角的增大非常规应力圆圆心偏离正应力轴的程度越大,揭示了应力路径的变化规律。基于Mohr-Coulomb强度理论,采用梯度下降算法,将7种倾角6个围压下应力圆上表示极限应力状态的“点”联系起来,求得7种倾角对应的7组强度包络线方程。采用多项式逼近方法,引入倾角维度,将7组“强度包络线”向“强度曲面”拓展,实现从“点”到“线”扩展到“面”的转变,构建包含倾角因素的岩石强度模型。研究结果对揭示矿柱等岩体工程强度的倾角-围压耦合效应具有重要科学意义。 展开更多
关键词 强度行为 倾角效应 围压效应 MOHR-COULOMB准则 梯度下降算法
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基于频谱效率公平性的XL-MIMO系统预编码优化
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作者 李志立 傅友华 宋云超 《数据采集与处理》 北大核心 2025年第6期1434-1444,共11页
本文研究了在近场信道模型下基于频谱效率公平性的超大规模多输入多输出(Extremely large‑scale multiple‑input‑multiple‑output,XL‑MIMO)下行系统的预编码优化问题。考虑在该近场信道模型,即小区内同时存在视距(Line‑of‑sight,LOS)和... 本文研究了在近场信道模型下基于频谱效率公平性的超大规模多输入多输出(Extremely large‑scale multiple‑input‑multiple‑output,XL‑MIMO)下行系统的预编码优化问题。考虑在该近场信道模型,即小区内同时存在视距(Line‑of‑sight,LOS)和非视距(Non LOS,NLOS)的非平稳混合信道,其中LOS信道采用球面波模型,而NLOS信道则采用瑞利模型。以频谱效率的几何平均值作为优化目标,从而确保用户间的公平性并优化系统整体的频谱效率。为了处理复杂的优化目标函数,首先对其采用泰勒展开的一阶近似作为新的目标函数。接着,使用拉格朗日对偶变换和二次变换将原始优化问题转化为更容易求解的等价问题。最后,为了降低计算复杂度,采用了快速迭代收缩阈值算法与投影梯度下降算法结合的投影快速迭代收缩阈值算法(Projection fast iterative shrinkage threshold algorithm,PFISTA)来解决等效优化问题。仿真结果显示,以几何平均值作为目标函数能够降低用户频谱效率之间的差异,实现用户频谱效率的均衡提升。此外,PFISTA在获得与现有方法相当性能的同时,具有较低的计算复杂度。 展开更多
关键词 非平稳 球面波 快速迭代收缩阈值算法 投影梯度下降 拉格朗日对偶变换
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基于SPGD算法的GTI腔短脉冲时域相干堆积闭环控制研究
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作者 刘必达 黄智蒙 +2 位作者 张帆 周丹丹 彭志涛 《光学与光电技术》 2025年第5期118-123,共6页
为了在短脉冲时域相干堆积系统中实现光腔相位高效闭环控制,利用一种基于扰动幅度e指数匀滑的随机并行梯度下降(Stochastic Parallel Gradient Descent Algorithm,SPGD)算法,对Gires-Tournois干涉仪(Gires-Tournois Interferometer,GTI... 为了在短脉冲时域相干堆积系统中实现光腔相位高效闭环控制,利用一种基于扰动幅度e指数匀滑的随机并行梯度下降(Stochastic Parallel Gradient Descent Algorithm,SPGD)算法,对Gires-Tournois干涉仪(Gires-Tournois Interferometer,GTI)堆积腔的相位进行闭环控制,实验研究了增益系数和扰动幅度两个主要算法参量对相干堆积效果的影响,结果表明,两个参数对堆积效果的影响规律相似,设置过小易陷入局部极值,过大会使得堆积波形发生振荡,无法稳定在最大值。通过优化控制参数选取,获得了稳定的相干堆积,合成后主、副脉冲峰值比达到6.43∶1。该结果对短脉冲时域相干堆积中的光腔相位控制具有重要的参考价值。 展开更多
关键词 光纤激光 短脉冲 脉冲相干堆积 光腔相位控制 随机并行梯度下降算法
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