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Dynamic bandwidth allocation algorithm for full-band utilization 被引量:1
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作者 Han Guodong Wang Hui Wu Jiangxing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期223-229,共7页
To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair... To improve and optimize the bandwidth utilization for multi-service packet transporting system, a kind of Dynamic Full Bandwidth Utilized (DFBU) allocation algorithm allowing a single link to use far beyond its fair share bandwidth is presented. Three important parameters as the bound on max and minimum bandwidth, the maximum packet delay and the minimum bandwidth utilization are discussed and analyzed. Results of experiments show that the DFBU-algorithm is capable of making a single link in the system use all the spare bandwidth (up to full-bandwidth) while the performance of fairness and QoS requirement is still guaranteed. 展开更多
关键词 full-band utilize dynamic allocation algorithm FAIRNESS bandwidth utilization
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Nested Genetic Algorithm for Resolving Overlapped Spectral Bands
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作者 Xiu Qi ZHANG Yun Hui ZENG +1 位作者 Jian Bin ZHENG Hong GAO(Institute of Electroanalytical Chemistry, Northwest University, Xi’an 710069) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第7期603-604,共2页
A nested genetic algorithm, including genetic parameter level and genetic implemented level for peak parameters, was proposed and applied for resolving overlapped spectral bands. By the genetic parameter level, parame... A nested genetic algorithm, including genetic parameter level and genetic implemented level for peak parameters, was proposed and applied for resolving overlapped spectral bands. By the genetic parameter level, parameters of generic algorithm were optimized; moreover, the number of overlapped peaks was determined simultaneously Then parameters of individual peaks were computed with the genetic implemented level. 展开更多
关键词 nested genetic algorithm resolving overlapped bands SPECTRA
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A Ka-band Solid-state Transmitter Cloud Radar and Data Merging Algorithm for Its Measurements 被引量:8
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作者 Liping LIU Jiafeng ZHENG Jingya WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第4期545-558,共14页
This study concerns a Ka-band solid-state transmitter cloud radar, made in China, which can operate in three different work modes, with different pulse widths, and coherent and incoherent integration numbers, to meet ... This study concerns a Ka-band solid-state transmitter cloud radar, made in China, which can operate in three different work modes, with different pulse widths, and coherent and incoherent integration numbers, to meet the requirements for cloud remote sensing over the Tibetan Plateau. Specifically, the design of the three operational modes of the radar(i.e., boundary mode M1, cirrus mode M2, and precipitation mode M3) is introduced. Also, a cloud radar data merging algorithm for the three modes is proposed. Using one month's continuous measurements during summertime at Naqu on the Tibetan Plateau,we analyzed the consistency between the cloud radar measurements of the three modes. The number of occurrences of radar detections of hydrometeors and the percentage contributions of the different modes' data to the merged data were estimated.The performance of the merging algorithm was evaluated. The results indicated that the minimum detectable reflectivity for each mode was consistent with theoretical results. Merged data provided measurements with a minimum reflectivity of -35 dBZ at the height of 5 km, and obtained information above the height of 0.2 km. Measurements of radial velocity by the three operational modes agreed very well, and systematic errors in measurements of reflectivity were less than 2 dB. However,large discrepancies existed in the measurements of the linear depolarization ratio taken from the different operational modes.The percentage of radar detections of hydrometeors in mid- and high-level clouds increased by 60% through application of pulse compression techniques. In conclusion, the merged data are appropriate for cloud and precipitation studies over the Tibetan Plateau. 展开更多
关键词 data merging algorithm operational mode Ka-band radar cloud Tibetan Plateau pulse compression technique
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An Algorithm in VC++ for Improving Ground Resolution of TM Band6
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《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期51-51,共1页
关键词 for Improving An algorithm in VC Ground Resolution of TM band6 TM
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Angular insensitive nonreciprocal ultrawide band absorption in plasma-embedded photonic crystals designed with improved particle swarm optimization algorithm
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作者 Yi-Han Wang Hai-Feng Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期352-363,共12页
Using an improved particle swarm optimization algorithm(IPSO)to drive a transfer matrix method,a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity is realized in plasma-embedded p... Using an improved particle swarm optimization algorithm(IPSO)to drive a transfer matrix method,a nonreciprocal absorber with an ultrawide absorption bandwidth and angular insensitivity is realized in plasma-embedded photonic crystals arranged in a structure composed of periodic and quasi-periodic sequences on a normalized scale.The effective dielectric function,which determines the absorption of the plasma,is subject to the basic parameters of the plasma,causing the absorption of the proposed absorber to be easily modulated by these parameters.Compared with other quasi-periodic sequences,the Octonacci sequence is superior both in relative bandwidth and absolute bandwidth.Under further optimization using IPSO with 14 parameters set to be optimized,the absorption characteristics of the proposed structure with different numbers of layers of the smallest structure unit N are shown and discussed.IPSO is also used to address angular insensitive nonreciprocal ultrawide bandwidth absorption,and the optimized result shows excellent unidirectional absorbability and angular insensitivity of the proposed structure.The impacts of the sequence number of quasi-periodic sequence M and collision frequency of plasma1ν1 to absorption in the angle domain and frequency domain are investigated.Additionally,the impedance match theory and the interference field theory are introduced to express the findings of the algorithm. 展开更多
关键词 magnetized plasma photonic crystals improved particle swarm optimization algorithm nonreciprocal ultra-wide band absorption angular insensitivity
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Genetic algorithm-based wide-band deterministic maximum likelihood direction finding algorithm
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作者 李福昌 赵春晖 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第3期510-514,共5页
The wide-band direction finding is one of hit and difficult task in array signal processing. This paper generalizes narrow-band deterministic maximum likelihood direction finding algorithm to the wideband case, and so... The wide-band direction finding is one of hit and difficult task in array signal processing. This paper generalizes narrow-band deterministic maximum likelihood direction finding algorithm to the wideband case, and so constructions an object function, then utilizes genetic algorithm for nonlinear global optimization. Direction of arrival is estimated without preprocessing of array data and so the algorithm eliminates the effect of pre-estimate on the final estimation. The algorithm is applied on uniform linear array and extensive simulation results prove the efficacy of the algorithm. In the process of simulation, we obtain the relation between estimation error and parameters of genetic algorithm. 展开更多
关键词 wide-band direction finding deterministic maximum likelihood genetic algorithm.
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Optimization of band-notched UWB antenna using micro-genetic algorithm combined with FDTD
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作者 杨雪霞 盛洁 《Journal of Shanghai University(English Edition)》 2009年第5期375-378,共4页
The micro-genetic algorithm (MGA) optimization combined with the finite-difference time-domain (FDTD) method is applied to design a band-notched ultra wide-band (UWB) antenna. A U-type slot on a stepped U-type UWB mon... The micro-genetic algorithm (MGA) optimization combined with the finite-difference time-domain (FDTD) method is applied to design a band-notched ultra wide-band (UWB) antenna. A U-type slot on a stepped U-type UWB monopole is used to obtain the band-notched characteristic for 5 GHz wireless local area network (WLAN) band. The measured results show that voltage standing wave ration (VSWR) less than 2 covers 3.1-10.6 GHz operating band and VSWR more than 2 is within 5.150-5.825 GHz notched one with the highest value of 5.6. Agreement among the calculated, HFSS simulated and measured results validates the effiectiveness of this MGA-FDTD method, which is efficient for UWB antennas design. 展开更多
关键词 finite-difference time-domain (FDTD) micro-genetic algorithm (MGA) ultra wide-band (UWB) antennas MONOPOLE band-notched antennas
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基于深度学习的多频带通信干扰信号滤除方法
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作者 姜育生 宋凯 《电子设计工程》 2026年第1期170-174,共5页
为解决复杂多变干扰环境下多频带通信质量受干扰信号显著影响且难以获得理想滤除效果的问题,研究基于深度学习算法的多频带通信干扰信号滤除方法。基于联合平移不变空间模型,分析多频带通信系统的信号特性,构建多频带通信模型。从多频... 为解决复杂多变干扰环境下多频带通信质量受干扰信号显著影响且难以获得理想滤除效果的问题,研究基于深度学习算法的多频带通信干扰信号滤除方法。基于联合平移不变空间模型,分析多频带通信系统的信号特性,构建多频带通信模型。从多频带模型中采集通信信号作为输入数据,输入到深度残差神经网络中进行处理。在神经网络架构中,卷积层采用滑动窗口机制,通过卷积操作生成干扰信号的特征图,将这些特征图传递至残差单元。残差单元对干扰信号进行全局特征映射,并将映射后的处理结果传递至全连接层。在全连接层,通过softmax函数对特征映射结果进行归一化处理,并利用L2损失函数优化网络训练过程。利用训练完成的深度残差神经网络,实现对多频带通信中干扰信号的有效滤除。实验结果表明,该方法不仅能够有效滤除干扰信号,而且滤除后的信噪比高达12 dB以上,同时噪声衰减因子保持在0.7以上。 展开更多
关键词 深度学习算法 多频带 通信干扰信号 滤除方法 残差单元 卷积层
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Detection of chemical oxygen demand in water based on UV absorption spectroscopy and PSO-LSSVM algorithm 被引量:3
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作者 ZHOU Kunpeng LIU Zhiyang +1 位作者 CONG Menglong MAN Shanxin 《Optoelectronics Letters》 EI 2022年第4期251-256,共6页
A method of detecting chemical oxygen demand(COD) of water based on ultraviolet(UV) absorption spectra is proposed. The modeling and analysis of the standard samples and the actual water samples are carried out respec... A method of detecting chemical oxygen demand(COD) of water based on ultraviolet(UV) absorption spectra is proposed. The modeling and analysis of the standard samples and the actual water samples are carried out respectively. For the standard solution samples, the univariate linear models based on single wavelengths and the partial least square(PLS) model based on synergy interval partial least square(Si PLS) and moving window partial least square(MWPLS) are established. For the actual water samples, different pre-processing methods are used. Si PLS and MWPLS are used to select the characteristic bands. The least squares support vector machine algorithm optimized by particle swarm optimization(PSO-LSSVM) algorithm is used to establish the prediction model, and the prediction results of various models are compared. The results show that the optimal model is PSO-LSSVM which uses Si PLS to select the characteristic bands of the first derivative spectra(preprocessing method). The determination coefficient of the prediction set is 0.963 1, and the root mean square error of prediction(RMSEP) is 2.225 4 mg/L. PSO-LSSVM algorithm has good prediction performance for the analysis of COD in actual water samples by UV spectra. This paper provides a new design idea for the research and development of water quality detection optical sensor. 展开更多
关键词 algorithm PREDICTION bandS
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UWB Positioning System Based on Genetic Algorithm 被引量:3
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作者 Bin Xia Xianzhi Zheng +1 位作者 Liye Zhang Lei Zhao 《Journal of Computer and Communications》 2021年第4期110-118,共9页
In order to enhance the positioning accuracy, a UWB positioning system based on genetic algorithm is proposed. Firstly, it uses the DW1000 module to measure the distance, and preprocesses the measured data to remove n... In order to enhance the positioning accuracy, a UWB positioning system based on genetic algorithm is proposed. Firstly, it uses the DW1000 module to measure the distance, and preprocesses the measured data to remove noise. Then, a positioning equation is established according to the processed distance information, and the genetic algorithm is used to solve the equation to obtain the coordinates of the unknown node. The experimental results show that the measured positioning accuracy is within 30 cm, which means that the system can obtain a good positioning effect and meet the need for precise positioning. 展开更多
关键词 LOCATION Ultra Wide band Genetic algorithm
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Classification of hyperspectral remote sensing images based on simulated annealing genetic algorithm and multiple instance learning 被引量:3
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作者 高红民 周惠 +1 位作者 徐立中 石爱业 《Journal of Central South University》 SCIE EI CAS 2014年第1期262-271,共10页
A hybrid feature selection and classification strategy was proposed based on the simulated annealing genetic algonthrn and multiple instance learning (MIL). The band selection method was proposed from subspace decom... A hybrid feature selection and classification strategy was proposed based on the simulated annealing genetic algonthrn and multiple instance learning (MIL). The band selection method was proposed from subspace decomposition, which combines the simulated annealing algorithm with the genetic algorithm in choosing different cross-over and mutation probabilities, as well as mutation individuals. Then MIL was combined with image segmentation, clustering and support vector machine algorithms to classify hyperspectral image. The experimental results show that this proposed method can get high classification accuracy of 93.13% at small training samples and the weaknesses of the conventional methods are overcome. 展开更多
关键词 hyperspectral remote sensing images simulated annealing genetic algorithm support vector machine band selection multiple instance learning
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Bidirectional reflectance one-dimensional rough distribution function modeling of surface in the microwave band
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作者 郭立新 苟雪银 张连波 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期302-310,共9页
In this study, the bidirectional reflectance distribution function (BRDF) of a one-dimensional conducting rough surface and a dielectric rough surface are calculated with different frequencies and roughness values i... In this study, the bidirectional reflectance distribution function (BRDF) of a one-dimensional conducting rough surface and a dielectric rough surface are calculated with different frequencies and roughness values in the microwave band by using the method of moments, and the relationship between the bistatic scattering coefficient and the BRDF of a rough surface is expressed. From the theory of the parameters of the rough surface BRDF, the parameters of the BRDF are obtained using a genetic algorithm. The BRDF of a rough surface is calculated using the obtained parameter values. Further, the fitting values and theoretical calculations of the BRDF are compared, and the optimization results are in agreement with the theoretical calculation results. Finally, a reference for BRDF modeling of a Gaussian rough surface in the microwave band is provided by the proposed method. 展开更多
关键词 bidirectional reflectance distribution function rough surface genetic algorithm microwave band
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像素级可见光/红外图像融合方法设计
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作者 翟书娟 刘磊 索艳滨 《激光与红外》 北大核心 2025年第8期1298-1304,共7页
像素级可见光/红外图像在成像过程中,低频子带系数和高频子带系数的能量分布在不同图像区域存在差异,对于可见光和红外图像融合而言,两者子带能量分布的差异更为复杂,这种能量分布的不均匀性使得当前的简单加权融合方法在匹配过程出现... 像素级可见光/红外图像在成像过程中,低频子带系数和高频子带系数的能量分布在不同图像区域存在差异,对于可见光和红外图像融合而言,两者子带能量分布的差异更为复杂,这种能量分布的不均匀性使得当前的简单加权融合方法在匹配过程出现一对多干扰,难以达到理想的融合效果,提出一种针对像素级可见光/红外图像的融合方法。将FAST特征点检测算法与ORB算法结合展开红外图像和可见光图像特征点检测,利用FLANN算法对提取出的特征点进行匹配,初步建立红外图像和可见光图像之间的对应关系,再通过RANSAC算法剔除误匹配的特征点对,解决单向匹配中存在的一对多匹配问题。基于图像配准结果,通过像素特征能量加权融合规则融合配准后图像的低频子带系数,基于邻域方差特征信息融合配准后图像的高频子带系数,组合低频子带系数和高频子带系数,生成最终的可见光红外融合图像。实验结果表明,所提方法确保了特征点匹配的双向一致性,解决了单向匹配中存在的一对多匹配问题,并且保留了图像细节,提升了信息丰富度,图像融合效果表现优异。 展开更多
关键词 图像融合 图像配准 ORB算法 低频高频子带系数 邻域方差
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基于轻量化融合网络的摇床精矿带分离点位置提取研究
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作者 刘惠中 刘建业 +2 位作者 黄翱 邓富龙 刘茜茜 《矿业研究与开发》 北大核心 2025年第10期199-206,共8页
针对现有摇床矿带目标检测算法存在检测精度和检测速度无法兼顾、计算成本高、模型大小难压缩和推理速度慢等问题,提出了一种摇床轻量化融合网络(YC-Lightweight Net)目标检测算法。YC-Lightweight Net模型首先采用重复视觉转换网络对... 针对现有摇床矿带目标检测算法存在检测精度和检测速度无法兼顾、计算成本高、模型大小难压缩和推理速度慢等问题,提出了一种摇床轻量化融合网络(YC-Lightweight Net)目标检测算法。YC-Lightweight Net模型首先采用重复视觉转换网络对摇床矿物分带图像进行特征提取,然后通过引入分组空间卷积、多尺度高效跨阶段融合模块并采用跳跃连接的方式设计了一种高效、轻量的颈部网络,最后采用基于权重的层自适应剪枝算法压缩模型大小。试验结果表明,YC-Lightweight Net模型精确度、召回率、平均精度均值和帧率指标分别为98.4%、97.9%、98.8%和333帧/s,检测精度和检测速度明显优于各对比模型;剪枝后参数量、浮点运算量和模型大小分别为原模型的13.9%、15.4%和17.5%,剪枝操作极大降低了模型的计算复杂度和模型大小。YC-Lightweight Net模型具有良好的检测精度和实时性能,满足摇床选矿厂的工业设备对模型轻量化的要求,可为摇床矿带分离点精准识别及选矿厂摇床设备智能化升级提供技术支持。 展开更多
关键词 摇床精矿带 目标检测 轻量化设计 LAMP算法 精准识别
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基于阶域线性峭度的变转速驱动轮损伤频带定位分析
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作者 张宏 李巨才 +2 位作者 王景宇 田利晨 张晨 《振动与冲击》 北大核心 2025年第7期232-238,共7页
掘进履带行驶系统作业于煤矿巷道恶劣地形和复杂环境中,其关键承载部件驱动轮长期承受不均匀载荷,导致轮齿损伤甚至断裂,影响掘进装备的正常生产作业和行驶平稳性。为了及时检测驱动轮轮齿损伤状态,避免故障扩大和降低维修成本,在阶次... 掘进履带行驶系统作业于煤矿巷道恶劣地形和复杂环境中,其关键承载部件驱动轮长期承受不均匀载荷,导致轮齿损伤甚至断裂,影响掘进装备的正常生产作业和行驶平稳性。为了及时检测驱动轮轮齿损伤状态,避免故障扩大和降低维修成本,在阶次跟踪算法、包络谱分析、线性峭度算法和滤波算法的基础上,提出了一种适用于变转速机械的阶域线性峭度算法。通过对只含基频、包含基频和谐频的合成仿真信号进行包络谱分析及特征分布统计,表明线性峭度相较于峭度更具优势。通过使用变转速和多噪声振动信号进行驱动轮齿损伤状态识别,并与快速谱峭度、阶域线性峭度等算法进行对比分析,表明阶域线性峭度算法具有适用性和鲁棒性。该方法可有效提高故障检测的准确性和效率,为履带行驶系统的安全健康运行提供了有力保障。 展开更多
关键词 履带行驶系统 轮齿损伤 线性峭度算法 变转速 频带定位
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基于5G天线和改进Dijkstra算法的露天矿车辆智能调度
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作者 陈晓磊 陈浏仿 王洁 《工矿自动化》 北大核心 2025年第11期133-140,共8页
露天矿深坑、高边坡等复杂地形造成信号物理遮挡与多径衰落,且现有路径规划算法易导致车辆行驶轨迹不稳定或由于局部最优引发拥堵,导致露天矿车辆调度效率低。针对上述问题,提出了一种基于5G天线和改进Dijkstra算法的露天矿车辆智能调... 露天矿深坑、高边坡等复杂地形造成信号物理遮挡与多径衰落,且现有路径规划算法易导致车辆行驶轨迹不稳定或由于局部最优引发拥堵,导致露天矿车辆调度效率低。针对上述问题,提出了一种基于5G天线和改进Dijkstra算法的露天矿车辆智能调度方法。在通信层面,基于双锥天线模型,通过加载L型辐射枝节,并在辐射贴片上设置矩形、L形缝隙优化电流分布,形成车载双频全向偶极子天线,实现了2.3~2.7 GHz与4.8~4.9 GHz双频段覆盖,解决了矿区深坑与高边坡造成的信号遮挡与衰减问题。在路径规划层面,对传统Dijkstra算法引入深度优先搜索与“容器数组”机制,通过记录节点所有潜在前驱信息实现全局路径回溯与择优,提高规划路径的平滑度。实验结果表明:双频全向偶极子天线在深坑与高边坡等信号遮挡严重区域的信号覆盖率达81.2%,平均信号强度为−94 dBm,高于传统商用5G天线;与Dijkstra算法、A*算法及快速遍历随机树(RRT)算法相比,改进Dijkstra算法规划的路径距离更短、拐点更少、轨迹更平滑,且在多车协同运输场景下路径冲突率低、重规划路径响应时间短;在实际露天矿的车辆调度中,与产量完成度法、最早装车法、车流规划法相比,所提方法能有效缩短车辆等待时间和满载行驶距离,且在单班总产量、空驶率及调度指令响应时延等指标上均最优。 展开更多
关键词 露天矿 车辆调度 5G天线 双频全向偶极子天线 DIJKSTRA算法 深度优先搜索 路径规划
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基于深度强化学习的窄带物联网自适应算法设计
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作者 孟洋 《通信电源技术》 2025年第8期36-38,共3页
窄带物联网(Narrow Band Internet of Things,NB-IoT)作为一种低功耗广域网络(Low-Power Wide Area Network,LPWAN)技术,在实际应用中面临动态频谱需求、高设备密度和信道条件波动等复杂挑战。为此,提出一种基于深度强化学习的自适应资... 窄带物联网(Narrow Band Internet of Things,NB-IoT)作为一种低功耗广域网络(Low-Power Wide Area Network,LPWAN)技术,在实际应用中面临动态频谱需求、高设备密度和信道条件波动等复杂挑战。为此,提出一种基于深度强化学习的自适应资源管理算法(Deep Reinforcement Learning-based Adaptive Resource Management Algorithm,DRL-ARMA)。该算法通过构建马尔可夫决策过程,对NB-IoT中的资源管理问题进行建模,并结合深度强化学习框架优化频谱分配、功率控制和调制方式选择。仿真实验结果表明,与传统的基于规则算法和随机分配算法相比,DRL-ARMA在吞吐量、延迟和能耗方面均展现出显著优势。所提出的算法有效地解决动态和复杂通信环境中的资源管理挑战,为NB-IoT中的智能资源分配提供一种新的技术方法和理论基础。 展开更多
关键词 窄带物联网(NB-IoT) 自适应算法 深度强化学习 动态优化
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云南墨江矿区周边山地农田土壤重金属的高光谱反演 被引量:3
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作者 田安红 李智缘 +1 位作者 付承彪 朱大明 《农业工程学报》 北大核心 2025年第5期191-200,F0003,共11页
为探究矿区周边山地农田土壤重金属的污染状况,实现在复合污染情境下山地农田土壤中多种重金属含量的高效反演。以云南省墨江县某金矿附近的农田区域为例,获取121个土壤样品实验室高光谱数据和重金属砷(As)、铬(Cr)、铜(Cu)、镍(Ni)的... 为探究矿区周边山地农田土壤重金属的污染状况,实现在复合污染情境下山地农田土壤中多种重金属含量的高效反演。以云南省墨江县某金矿附近的农田区域为例,获取121个土壤样品实验室高光谱数据和重金属砷(As)、铬(Cr)、铜(Cu)、镍(Ni)的含量数据,构建高精度的高光谱反演模型,实现对不同重金属含量的定量反演。结果表明:1)内梅罗污染指数法显示研究区土壤处于重度污染状态,潜在生态风险指数法显示该区域处于中等生态风险水平。2)一阶微分、二阶微分、标准正态变量以及倒数的对数能有效增强光谱响应,竞争性自适应重加权算法(competitive adaptive reweighted sampling,CARS)的高效波段筛选能力结合迭代保留信息变量(iteratively retains informative variables,IRIV)算法的变量精炼优势,能够实现在土壤重金属反演中的敏感波段选择,该方法在特征波段数量、计算运行时间和模型反演精度方面都比单独的CARS和IRIV方法更有效。3)对比发现反向传播神经网络(back-propagation neural network,BPNN)在As反演中取得最佳反演精度,支持向量机(support vector machine,SVM)为Cr、Cu和Ni的最优反演模型,As、Cr、Cu、Ni最优反演模型的R^(2)分别为0.90、0.93、0.67、0.94,均方根误差(root mean squared error of external validation,RMSE)分别为87.33、142.63、2.63、70.31 mg/kg,相对分析误差(relative percent difference,RPD)分别为3.25、3.84、1.74、4.17。4)重金属的空间分布结果显示,高值区域主要集中在研究区的上下部分,而低值区域则主要分布在边缘,整体呈现从中心向四周逐渐降低的趋势。该研究可为监测矿区附近农田土壤重金属复合污染状况提供参考依据。 展开更多
关键词 高光谱 反演 机器学习 土壤重金属 IRIV算法 特征波段选择
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基于GA-BP神经网络的宽带激光熔覆裂纹缺陷预测
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作者 史墨可 路妍 +4 位作者 颉潭成 王军华 徐彦伟 倪崇智 翟文豪 《热加工工艺》 北大核心 2025年第12期119-123,128,共6页
针对宽带激光熔覆裂纹缺陷难以准确预测问题,以扫描速度、搭接率、激光功率作为输入,以熔覆试样裂纹密度为输出,建立了BP神经网络裂纹缺陷预测模型。采用遗传算法优化了BP神经网络的初始阈值和权值,对比分析了模型优化前后的相对误差。... 针对宽带激光熔覆裂纹缺陷难以准确预测问题,以扫描速度、搭接率、激光功率作为输入,以熔覆试样裂纹密度为输出,建立了BP神经网络裂纹缺陷预测模型。采用遗传算法优化了BP神经网络的初始阈值和权值,对比分析了模型优化前后的相对误差。结果表明:GA-BP神经网络模型的相对误差在0.22%~2.10%;BP神经网络模型的相对误差在2.09%~14.31%,GA-BP神经网络模型的预测精度远远高于BP神经网络模型。 展开更多
关键词 BP神经网络 裂纹 正交试验 遗传算法 宽带激光熔覆
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变量耦合动态监控光学膜厚补偿技术
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作者 杜昕 付秀华 +3 位作者 董所涛 潘永刚 王由德 谢海峰 《中国光学(中英文)》 北大核心 2025年第3期467-476,共10页
为提高红外波段膜厚控制精度和实现波长精准定位,基于LabVIEW编程语言,开展了以光学膜厚监控系统为基础的变量耦合动态监控光学膜厚补偿技术研究。基于光的干涉以及光学薄膜设计理论,采用光电极值法构建数学模型,重点解决极值点判停误... 为提高红外波段膜厚控制精度和实现波长精准定位,基于LabVIEW编程语言,开展了以光学膜厚监控系统为基础的变量耦合动态监控光学膜厚补偿技术研究。基于光的干涉以及光学薄膜设计理论,采用光电极值法构建数学模型,重点解决极值点判停误差和滤波除噪等问题,高度还原实时采集的光量值的监控数据,实时同步拟合膜厚监控的透射曲线,计算并拟合膜厚极值点以及任意目标厚度对应的停镀点,实现膜厚有效准确的判停。为了验证光控系统的可靠性和稳定性,通过制备1064 nm窄带滤光膜对系统进行验证。结果表明,制备的1064 nm窄带滤光膜单面峰值透过率为91.5%,通带半宽度为5 nm,经计算,监控系统误差小于0.01%。 展开更多
关键词 光学薄膜 膜厚监控 拟合算法 窄带滤光膜
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