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Small Target Extraction Based on Independent Component Analysis for Hyperspectral Imagery 被引量:3
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作者 LU Wei YU Xuchu 《Geo-Spatial Information Science》 2006年第2期103-107,共5页
A small target detection approach based on independent component analysis for hyperspectral data is put forward. In this algorithm, firstly the fast independent component analysis(FICA) is used to collect target infor... A small target detection approach based on independent component analysis for hyperspectral data is put forward. In this algorithm, firstly the fast independent component analysis(FICA) is used to collect target information hided in high-dimensional data and projects them into low-dimensional space.Secondly, the feature images are selected with kurtosis .At last, small targets are extracted with histogram image segmentation which has been labeled by skewness. 展开更多
关键词 fast independent component analysis SKEWNESS KURTOSIS target extraction
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ICA Based Speckle Filtering for Target Extraction in SAR Images Using Adaptive Space Separation
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作者 李昱彤 周越 杨磊 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第5期528-532,共5页
A novel approach based on independent component analysis (ICA) for speckle filtering and target extraction of synthetic aperture radar (SAR) images is proposed using adaptive space separation with weighted information... A novel approach based on independent component analysis (ICA) for speckle filtering and target extraction of synthetic aperture radar (SAR) images is proposed using adaptive space separation with weighted information entropy (WIE) incorporated. First the basis and the independent components are respectively obtained by ICA technique, and WIE of the image is computed; then based on the threshold computed from function T-WIE (threshold versus weighted-information-entropy), independent components are adaptively separated and the bases are classified accordingly. Thus, the image space is separated into two subspaces: "clean" and "noise". Then, a proposed nonlinear operator ABO is applied on each component of the 'clean' subspace for further optimization. Finally, recovery image is obtained reconstructing this subspace and target is easily extracted with binarisation. Note that here T-WIE is an interpolated function based on several representative target SAR images using proposed space separation algorithm. 展开更多
关键词 target extraction speckle filtering synthetic aperture radar (SAR) independent component analysis (ICA) adaptive space separation weighted information entropy (WIE)
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A Model for Cross-Domain Opinion Target Extraction in Sentiment Analysis
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作者 Muhammet Yasin PAK Serkan GUNAL 《Computer Systems Science & Engineering》 SCIE EI 2022年第9期1215-1239,共25页
Opinion target extraction is one of the core tasks in sentiment analysison text data. In recent years, dependency parser–based approaches have beencommonly studied for opinion target extraction. However, dependency p... Opinion target extraction is one of the core tasks in sentiment analysison text data. In recent years, dependency parser–based approaches have beencommonly studied for opinion target extraction. However, dependency parsersare limited by language and grammatical constraints. Therefore, in this work, asequential pattern-based rule mining model, which does not have such constraints,is proposed for cross-domain opinion target extraction from product reviews inunknown domains. Thus, knowing the domain of reviews while extracting opinion targets becomes no longer a requirement. The proposed model also revealsthe difference between the concepts of opinion target and aspect, which are commonly confused in the literature. The model consists of two stages. In the firststage, the aspects of reviews are extracted from the target domain using the rulesautomatically generated from source domains. The aspects are also transferredfrom the source domains to a target domain. Moreover, aspect pruning is appliedto further improve the performance of aspect extraction. In the second stage, theopinion target is extracted among the aspects extracted at the former stage usingthe rules automatically generated for opinion target extraction. The proposedmodel was evaluated on several benchmark datasets in different domains andcompared against the literature. The experimental results revealed that the opiniontargets of the reviews in unknown domains can be extracted with higher accuracythan those of the previous works. 展开更多
关键词 Opinion target extraction aspect extraction sentiment analysis
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Target extraction through strong scattering disturbance using characteristic-enhanced pseudo-thermal ghost imaging 被引量:2
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作者 Xuanpengfan Zou Xianwei Huang +7 位作者 Wei Tan Liyu Zhou Xiaohui Zhu Qin Fu Xiaoqian Liang Suqin Nan Yanfeng Bai Xiquan Fu 《Chinese Optics Letters》 CSCD 2024年第12期38-44,共7页
It is difficult to extract targets under strong environmental disturbance in practice.Ghost imaging(GI)is an innovative antiinterference imaging technology.In this paper,we propose a scheme for target extraction based... It is difficult to extract targets under strong environmental disturbance in practice.Ghost imaging(GI)is an innovative antiinterference imaging technology.In this paper,we propose a scheme for target extraction based on characteristicenhanced pseudo-thermal GI.Unlike traditional GI which relies on training the detected signals or imaging results,our scheme trains the illuminating light fields using a deep learning network to enhance the target’s characteristic response.The simulation and experimental results prove that our imaging scheme is sufficient to perform single-and multiple-target extraction at low measurements.In addition,the effect of a strong scattering environment is discussed,and the results show that the scattering disturbance hardly affects the target extraction effect.The proposed scheme presents the potential application in target extraction through scattering media. 展开更多
关键词 target extraction ghost imaging characteristic enhancement strong scattering environment
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Parallel Extraction of Marine Targets Applying OIDA Architecture
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作者 LIU Lin LI Wanwu +2 位作者 ZHANG Jixian SUN Yi CUI Yumeng 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第3期737-747,共11页
Computing resources are one of the key factors restricting the extraction of marine targets by using deep learning.In order to increase computing speed and shorten the computing time,parallel distributed architecture ... Computing resources are one of the key factors restricting the extraction of marine targets by using deep learning.In order to increase computing speed and shorten the computing time,parallel distributed architecture is adopted to extract marine targets.The advantages of two distributed architectures,Parameter Server and Ring-allreduce architecture,are combined to design a parallel distributed architecture suitable for deep learning–Optimal Interleaved Distributed Architecture(OIDA).Three marine target extraction methods including OTD_StErf,OTD_Loglogistic and OTD_Sgmloglog are used to test OIDA,and a total of 18 experiments in 3categories are carried out.The results show that OIDA architecture can meet the timeliness requirements of marine target extraction.The average speed of target parallel extraction with single-machine 8-core CPU is 5.75 times faster than that of single-machine single-core CPU,and the average speed with 5-machine 40-core CPU is 20.75 times faster. 展开更多
关键词 parallel computing distributed architecture deep learning target extraction PolSAR image
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves Non-target organisms Safety evaluation
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Novel and Comprehensive Approach for the Feature Extraction and Recognition Method Based on ISAR Images of Ship Target 被引量:1
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作者 Yong Wang Pengkai Zhu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第5期12-19,共8页
This paper proposes a novel and comprehensive method of automatic target recognition based on real ISAR images with the aim to recognize the non-cooperative ship targets. The special characteristics of the ISAR images... This paper proposes a novel and comprehensive method of automatic target recognition based on real ISAR images with the aim to recognize the non-cooperative ship targets. The special characteristics of the ISAR images for the real data compared with the simulated ISAR images are analyzed firstly. Then,the novel technique for the target recognition is proposed,and it consists of three steps,including the preprocessing,feature extraction and classification. Some segmentation and morphological methods are used in the preprocessing to obtain the clear target images. Then,six different features for the ISAR images are extracted.By estimating the features' conditional probability, the effectiveness and robustness of these features are demonstrated. Finally,Fisher's linear classifier is applied in the classification step. The results for the allfeature space are provided to illustrate the effectiveness of the proposed method. 展开更多
关键词 ISAR images FEATURE extraction recognition SHIP target
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3D feature extraction of head based on target region matching
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作者 YU Hai-bin LIU Ji-lin LIU Jing-bia 《通讯和计算机(中英文版)》 2008年第5期1-6,共6页
关键词 3D技术 区域匹配 计算机技术 MSF
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Feature Extraction for Acoustic Scattering from a Buried Target 被引量:2
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作者 Xiukun Li Yushuang Wu 《Journal of Marine Science and Application》 CSCD 2019年第3期380-386,共7页
Elastic acoustic scattering is important for buried target detection and identification. For elastic spherical objects, studies have shown that a series of narrowband energetic arrivals follow the first specular one. ... Elastic acoustic scattering is important for buried target detection and identification. For elastic spherical objects, studies have shown that a series of narrowband energetic arrivals follow the first specular one. However, in practice, the elastic echo is rather weak because of the acoustic absorption, propagation loss, and reverberation, which makes it difficult to extract elastic scattering features, especially for buried targets. To remove the interference and enhance the elastic scattering, the de-chirping method was adopted here to address the target scattering echo when a linear frequency modulation (LFM) signal is transmitted. The parameters of the incident signal were known. With the de-chirping operation, a target echo was transformed into a cluster of narrowband signals, and the elastic components could be extracted with a band-pass filter and then recovered by remodulation. The simulation results indicate the feasibility of the elastic scattering extraction and recovery. The experimental result demonstrates that the interference was removed and the elastic scattering was visibly enhanced after de-chirping, which facilitates the subsequent resonance feature extraction for target classification and recognition. 展开更多
关键词 BURIED target detection Acoustic SCATTERING ELASTIC SCATTERING De-chirping FEATURE extraction
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机载长合成孔径时间海面运动舰船高分辨SAR成像算法
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作者 陈凯 赵永波 +2 位作者 刘仍莉 邓海涛 孙龙 《系统工程与电子技术》 北大核心 2026年第2期456-465,共10页
为解决海面运动舰船因转动分量不足使得逆合成孔径雷达处理成像分辨率低,以及舰船的非合作性运动导致合成孔径雷达成像散焦的问题,提出一种机载长合成孔径时间海面运动舰船高分辨合成孔径雷达成像算法。首先基于子孔径成像处理完成舰船... 为解决海面运动舰船因转动分量不足使得逆合成孔径雷达处理成像分辨率低,以及舰船的非合作性运动导致合成孔径雷达成像散焦的问题,提出一种机载长合成孔径时间海面运动舰船高分辨合成孔径雷达成像算法。首先基于子孔径成像处理完成舰船目标检测和信号提取,接着利用子孔径之间距离多普勒自适应相关搜索完成舰船信号全孔径归集。在舰船信号集合的过程中,同步完成距离对齐和平动误差补偿。最后利用基于匹配傅里叶变换的方法进行舰船的转动参数估计,实现转动误差补偿,完成长合成孔径时间舰船目标的高分辨合成孔径雷达成像。实验结果和对比分析表明,所提方法对海面运动舰船可以实现高分辨成像,点目标可有效聚焦,相比传统方法,舰船目标散射点细节更明显,验证了所提方法的有效性。 展开更多
关键词 舰船成像 长合成孔径时间 目标检测和信号提取 目标信号归集 匹配傅里叶变换 子孔径
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基于改进SDU-YOLOv8的军事飞机目标检测算法
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作者 赵海丽 包大泱 +3 位作者 张从豪 刘鹏 王彩霞 景文博 《兵工学报》 北大核心 2026年第1期296-306,共11页
针对空天背景下军事飞机目标检测中存在的低对比度、小尺寸及形态多变导致的漏检率高、特征交互不足等问题,提出基于YOLOv8改进的SDU-YOLOv8网络。通过构建SSGBlock深度特征提取模块、动态可学习的Dy-RepGFPN特征融合网络以及参数共享的... 针对空天背景下军事飞机目标检测中存在的低对比度、小尺寸及形态多变导致的漏检率高、特征交互不足等问题,提出基于YOLOv8改进的SDU-YOLOv8网络。通过构建SSGBlock深度特征提取模块、动态可学习的Dy-RepGFPN特征融合网络以及参数共享的UCDN-Head检测头,实现特征提取、融合与检测头的协同优化。在自建军事飞机数据集上的实验结果表明,SDU-YOLOv8网络较基准YOLOv8的mAP@0.5提升2.5%,达到95.7%,参数量减少6.7%,计算量降低9.9%,在小尺寸、低对比度及形变目标的检测鲁棒性显著增强;新方法在保持轻量化的同时实现了检测精度与效率的均衡优化,为空天侦察场景下的军事飞机检测提供了高效解决方案。 展开更多
关键词 军事飞机目标检测 YOLOv8 深度特征提取 动态上采样 统一参数化
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增香菌发酵烟草浸提液制备清甜香烟用香料及机理研究
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作者 薛磊 程家明 +6 位作者 王颖 宋士兮 王旭锋 张增辉 黄申 毛多斌 邓宝安 《安徽农业科学》 2026年第2期93-101,137,共10页
[目的]制备清甜香型烟用香料,研究其作用机理。[方法]以烟叶浸提液为发酵培养基,优化发酵条件,通过乙醇冷萃法处理发酵液制备香料,采用GC-MS对香料的香味成分进行分析,结合感官评价评估其在卷烟中的应用效果,利用非靶向代谢组学探讨发... [目的]制备清甜香型烟用香料,研究其作用机理。[方法]以烟叶浸提液为发酵培养基,优化发酵条件,通过乙醇冷萃法处理发酵液制备香料,采用GC-MS对香料的香味成分进行分析,结合感官评价评估其在卷烟中的应用效果,利用非靶向代谢组学探讨发酵机理。[结果]当烟草浸提液波美度为5.2°Bé,发酵温度为35℃发酵,发酵时间为41.5h,pH为7,搅拌速度为154 r/min时,制得香料香气呈显著的蜜甜、清甜和花香特征,香料加入卷烟后,香气质、香气量、甜感和余味均有明显改善,清甜感尤为突出;与发酵前相比,乙基麦芽酚、巨豆三烯酮和β-愈创木酚等香气成分含量显著增加;非靶向代谢组学结果显示,增香菌在发酵前后存在显著的代谢差异,共鉴定出236个上调代谢物和495个下调代谢物,其中与生物碱生物合成、糖苷代谢及酪氨酸代谢相关的代谢途径较为丰富。[结论]为利用微生物发酵烟草浸提液制备烟用香料提供重要理论支撑,弥补清甜香香料来源较少的问题。 展开更多
关键词 烟草浸提液 非靶向代谢组学 发酵条件优化 烟用香料
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一种基于复合框架的城市道路场景车辆轨迹提取方法
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作者 田晟 冯帅涛 李嘉 《广西师范大学学报(自然科学版)》 北大核心 2026年第2期31-51,共21页
城市道路车辆轨迹提取对智能交通监管至关重要,但现有技术存在检测精度低、身份跳变导致轨迹断裂等问题。为了解决这些问题,本文提出融合改进YOLOv7-tiny检测、StrongSORT跟踪与Savitzky-Golay滤波优化的复合框架(integrated framework ... 城市道路车辆轨迹提取对智能交通监管至关重要,但现有技术存在检测精度低、身份跳变导致轨迹断裂等问题。为了解决这些问题,本文提出融合改进YOLOv7-tiny检测、StrongSORT跟踪与Savitzky-Golay滤波优化的复合框架(integrated framework of improved YOLOv7-tiny detection,StrongSORT tracking,and Savitzky-Golay filtering optimization,IYSSG)。该框架能够利用交通监控设备采集的城市道路监控视频数据,高效提取不同车辆目标的轨迹。经过实验评估,IYSSG框架在3个主要任务中表现出色。在车辆检测方面,改进后的YOLOv7-tiny算法在保障检测速度的同时,精度、召回率和mAP@0.5相较于原始YOLOv7-tiny算法分别提升2.5、8.5和3.7个百分点;在车辆跟踪方面,StrongSORT算法相比于DeepSORT算法,MOTA(multiple object tracking accuracy)和MOTP(multiple object tracking precision)指标分别取得4.92和2.7个百分点的提升;在车辆轨迹提取与优化方面,Savitzky-Golay滤波算法有效解决因视频抖动和算法误差等客观因素导致的轨迹点缺失和轨迹不平滑问题,有助于研究人员从交通监控视频中提取精确的车辆轨迹,从而更好地分析定位交通问题。 展开更多
关键词 YOLOv7-tiny 目标检测 深度学习 多目标跟踪 轨迹提取 城市道路 车辆轨迹
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基于WEED-YOLOv10的玉米杂草检测方法与对靶喷药系统设计
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作者 赵建国 安美林 +5 位作者 赵学观 王雅雅 马志凯 李媛普 王博奥 郝建军 《农业工程学报》 北大核心 2026年第1期48-57,共10页
针对玉米杂草识别过程中因光照变化导致识别精确度低及漏检问题,该研究以幼苗期玉米及其伴生杂草为研究对象,设计一种基于WEED-YOLOv10的玉米杂草检测方法。首先,通过无人机快速采集田间高分辨率图像构建了玉米杂草数据集;其次,以YOLOv... 针对玉米杂草识别过程中因光照变化导致识别精确度低及漏检问题,该研究以幼苗期玉米及其伴生杂草为研究对象,设计一种基于WEED-YOLOv10的玉米杂草检测方法。首先,通过无人机快速采集田间高分辨率图像构建了玉米杂草数据集;其次,以YOLOv10n为基线网络,将骨干网络替换为ConvNeXtV2以增强特征提取能力;继而,为避免因模块拼接可能带来的信息冗余或丢失问题提升对光照干扰的鲁棒性,嵌入CBAM注意力机制;然后,引入SlimNeck结构优化网络计算效率,有效平衡了模型计算资源消耗与特征表征能力;最后,使用Focaler-EIoU损失函数进一步提高模型定位精度。试验结果表明,WEED-YOLOv10在精确率、召回率、mAP@50、mAP@50:95和F1分数上分别达到85.4%、88.1%、90.9%、48.5%和86.7%,较基准模型分别提升了2.4、2.9、3.5、7.0、2.6个百分点,各项精度指标均优于其他对比模型,部署在NVIDIA Jetson orin NX上的图片推理速度达到28.7帧/s,实现了检测速度与精度的平衡。进一步地,基于WEED-YOLOv10开发对靶喷药系统,该系统实时捕捉并解析来自模型的识别信号,实现对除草喷施装置的精准调控。田间试验结果显示,对靶喷药系统施药准确率为93.7%,喷洒覆盖率为90.5%,对靶偏差为1.45cm,杂草实时检测速度为20.1帧/s,实现了自动化的玉米田间除草作业。该研究为复杂光照场景下农田杂草治理提供了可靠的技术方案,对推动农业智能化作业具有重要意义。 展开更多
关键词 杂草识别 YOLOv10n 特征提取 注意力机制 SlimNeck 对靶喷药系统
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Research on weak signal extraction and noise removal for GPR data based on principal component analysis 被引量:1
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作者 CHEN Lingna ZENG Zhaofa +1 位作者 LI Jing YUAN Yuan 《Global Geology》 2015年第3期196-202,共7页
The ground penetrating radar (GPR) detection data is a wide band signal, always disturbed by some noise, such as ambient random noise and muhiple refleetion waves. The noise affects the target identification of unde... The ground penetrating radar (GPR) detection data is a wide band signal, always disturbed by some noise, such as ambient random noise and muhiple refleetion waves. The noise affects the target identification of underground medium seriously. A method based on principal component analysis (PCA) was proposed to ex- tract the target signal and remove the uncorrelated noise. According to the correlation of signal, the authors get the eigenvalues and corresponding eigenvectors by decomposing the covariance matrix of GPR data and make linear transformation for the GPR data to get the principal components (PCs). The lower-order PCs stand h^r the strong correlated target signals of the raw data, and the higher-order ones present the uneorrelated noise. Thus the authors can extract the target signal and filter uncorrelated noise effectively by the PCA. This method was demonstrated on real ultra-wideband through-wall radar data and simulated GPR data. Both of the results show that the PCA method can effectively extract the GPR target signal and remove the uncorrelated noise. 展开更多
关键词 ground penetrating radar principal component analysis target extraction noise removing
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卷积神经网络下机器人目标跟踪方法研究
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作者 薛岚 杨帅 +1 位作者 史宜巧 李凯勇 《机械设计与制造》 北大核心 2026年第2期380-384,共5页
由于传统跟踪方法忽略了对图像特征的多维加权,导致该方法只能处理单维机器人图像数据,无法满足当前机器人领域的要求。为此,将卷积神经网络下的跟踪方法应用在机器人中,实现机器人目标高精度跟踪。在卷积神经网络中增加特征图多维加权... 由于传统跟踪方法忽略了对图像特征的多维加权,导致该方法只能处理单维机器人图像数据,无法满足当前机器人领域的要求。为此,将卷积神经网络下的跟踪方法应用在机器人中,实现机器人目标高精度跟踪。在卷积神经网络中增加特征图多维加权层,强化特征图空间信息。随机选择机器人跟踪目标物体,利用卷积神经网络在机器人视觉控制系统中获取图像特征,根据图像特征误差构建视觉滑模定位控制律,完成机器人的物体视觉跟踪目标。仿真结果表明,卷积神经网络能大幅提升机器人目标跟踪精度,且跟踪路径与目标路径具有较高一致度,为机器人更好地实现目标跟踪提供可靠参考意见。 展开更多
关键词 卷积神经网络 目标跟踪 机器人 特征提取 控制律
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星载合成孔径雷达在海洋监测中的应用
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作者 朱泠 陈鹏 +3 位作者 郑罡 杨劲松 朱海天 任林 《海洋学研究》 北大核心 2026年第1期109-123,共15页
星载合成孔径雷达(synthetic aperture radar,SAR)具备全天时、全天候工作能力,在海洋监测方面已展现出巨大的应用价值。本文从海洋动力环境要素和海洋目标两个方面,系统总结了星载SAR技术在海洋监测领域的研究现状。对于前者,重点梳理... 星载合成孔径雷达(synthetic aperture radar,SAR)具备全天时、全天候工作能力,在海洋监测方面已展现出巨大的应用价值。本文从海洋动力环境要素和海洋目标两个方面,系统总结了星载SAR技术在海洋监测领域的研究现状。对于前者,重点梳理了SAR用于海浪、内波、涡旋、风场、海流及海底地形等环境要素监测的主流技术与算法,并深入讨论了多波段、多极化与多模式SAR数据在提升反演精度方面的作用;对于后者,则系统总结了海冰、溢油、船舶及海上人工设施等海洋目标的识别方法,阐明了多极化信息在刻画目标散射特性中的关键贡献。此外,本文进一步评述了人工智能技术在SAR海洋监测中的进展,并对未来SAR海洋遥感技术的发展方向进行了探讨。 展开更多
关键词 SAR 极化特征 海洋遥感 海洋动力环境 海上目标 海洋信息提取 人工智能 反演算法
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基于孪生神经网络特征提取的垂直阵目标距离估计方法
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作者 赵吉祥 秦志亮 +3 位作者 马本俊 兰文剑 燕欣艺 郑毅 《声学学报》 北大核心 2026年第1期63-76,共14页
针对深度学习水下声源距离估计中存在的离散化标签多、类内样本少导致模型特征学习受限的问题,提出了一种基于孪生神经网络特征提取的目标距离估计方法。首先通过仿真数据构建以距离为标签的正、负样本对数据集,设计并训练了孪生神经网... 针对深度学习水下声源距离估计中存在的离散化标签多、类内样本少导致模型特征学习受限的问题,提出了一种基于孪生神经网络特征提取的目标距离估计方法。首先通过仿真数据构建以距离为标签的正、负样本对数据集,设计并训练了孪生神经网络以提取声源距离特征;进而基于迁移学习策略分别构建了卷积神经网络距离估计模型(S-CNN)和残差神经网络距离估计模型(S-ResNet)。仿真实验表明该方法能够有效提升距离敏感特征的表达能力,S-CNN/S-ResNet相比无特征提取的NS-CNN/NS-ResNet距离估计性能均有提升,且S-ResNet在不同训练样本数量、信噪比和环境误差下均优于S-CNN方法;SWellEX-96试验结果表明所提方法显著优于传统匹配场定位,且S-ResNet在距离估计可信概率(领先约10%)和平均百分比误差(降低约2%)两项指标上均优于S-CNN方法。 展开更多
关键词 孪生神经网络 声源距离估计 特征提取 水下目标 垂直阵
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Algorithm of the Real-Time Extraction Image for Vehicle
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作者 LIU Quan HUANG Guo sheng 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第2期178-180,共3页
An algorithm applied to a real-time extraction image of vehicle is introduced. The algorithm include an image processing with a binarzation method, image grab for a vehicle with high speed, character isolator one by o... An algorithm applied to a real-time extraction image of vehicle is introduced. The algorithm include an image processing with a binarzation method, image grab for a vehicle with high speed, character isolator one by one, and neural network algorithm. The techniques include vehicles sensing, image garb control, vehicle license location, lighting and optic character recognition. The system is much more robust and faster than the traditional thresholding method. 展开更多
关键词 Key words image processing target extraction BINARIZATION neural network
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基于特征参数提取的智能电磁散射分析方法进展
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作者 张文炜 曹嘉宁 +3 位作者 康家齐 黄文驰 孔德铧 夏明耀 《电波科学学报》 北大核心 2026年第1期42-52,共11页
计算电磁学(computational electromagnetics,CEM)方法在雷达目标特性优化、天线分析设计、微波器件与系统建模等电磁工程应用中处于核心地位。传统的CEM方法历经半个多世纪的发展已趋于成熟。近年来,得益于人工智能的快速发展,智能电... 计算电磁学(computational electromagnetics,CEM)方法在雷达目标特性优化、天线分析设计、微波器件与系统建模等电磁工程应用中处于核心地位。传统的CEM方法历经半个多世纪的发展已趋于成熟。近年来,得益于人工智能的快速发展,智能电磁计算这一新兴领域受到高度关注,旨在降低传统方法的技术实现难度,在保证结果精度的条件下大幅提高仿真速度。本文聚焦于智能电磁计算在电磁散射分析方面的应用,讨论了一类基于目标特征参数学习与提取的智能电磁计算方法。其中的特征参数为一组连接目标结构属性与目标电磁特性的参数,具有类似于系统传递函数的功能,一旦获得便可用来计算针对任何入射和观测方向的散射远场。同时,对该类方法的下一步发展进行了展望。 展开更多
关键词 智能电磁计算 电磁散射特性 目标特征参数 机器学习(ML) 特征提取
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