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Numerical Studies of Divided Aperture Techniques in Confocal System 预览
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作者 Haonan Lai 《电力能源(英文)》 2019年第11期42-46,共5页
This paper performs a numerical study of the imaging process in confocal microscopy. We simulate the imaging result using Fresnel diffraction formula. We also consider the divided aperture technique in confocal system... This paper performs a numerical study of the imaging process in confocal microscopy. We simulate the imaging result using Fresnel diffraction formula. We also consider the divided aperture technique in confocal system. Different aperture shapes were varied to achieve best performance in terms of resolution and integrated intensity. Here, the D-shaped achieves the best performance in x-axis resolution, while the annular aperture shape is the worst for integrated intensity. We propose using different aperture shapes for various biomedical applications. 展开更多
关键词 CONFOCAL MICROSCOPY APERTURE RESOLUTION Integrated INTENSITY
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A fast decoupled ISAR high-resolution imaging method using structural sparse information under low SNR 预览
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作者 XIANG Long LI Shaodong +2 位作者 YANG Jun CHEN Wenfeng XIANG Hu 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第3期492-503,共12页
Inverse synthetic aperture radar (ISAR) image can be represented and reconstructed by sparse recovery (SR) approaches. However, the existing SR algorithms, which are used for ISAR imaging, have suffered from high comp... Inverse synthetic aperture radar (ISAR) image can be represented and reconstructed by sparse recovery (SR) approaches. However, the existing SR algorithms, which are used for ISAR imaging, have suffered from high computational cost and poor imaging quality under a low signal to noise ratio (SNR) condition. This paper proposes a fast decoupled ISAR imaging method by exploiting the inherent structural sparse information of the targets. Firstly, the ISAR imaging problem is decoupled into two sub-problems. One is range direction imaging and the other is azimuth direction focusing. Secondly, an efficient two-stage SR method is proposed to obtain higher resolution range profiles by using jointly sparse information. Finally, the residual linear Bregman iteration via fast Fourier transforms (RLBI-FFT) is proposed to perform the azimuth focusing on low SNR efficiently. Theoretical analysis and simulation results show that the proposed method has better performence to efficiently implement higher-resolution ISAR imaging under the low SNR condition. 展开更多
关键词 SPARSE recovery inverse synthetic APERTURE radar (ISAR) imaging HIGH-RESOLUTION signal to noise ratio (SNR) STRUCTURAL SPARSE INFORMATION
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A jamming method against bistatic SAR based on modulation theory 预览
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作者 RANJinhe LIXiuhe SHEN yang 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第3期504-510,共7页
This paper focuses on the jamming problem of bistatic synthetic aperture radar (BiSAR), and a jamming method against BiSAR based on modulation theory is proposed. The proposed jamming method modulates the BiSAR signal... This paper focuses on the jamming problem of bistatic synthetic aperture radar (BiSAR), and a jamming method against BiSAR based on modulation theory is proposed. The proposed jamming method modulates the BiSAR signal with the cosinusoidal phase to generate multi-false targets in range, and further rotates the jammer to generate multi-false targets in azimuth. The range multi-false targets and azimuth multi-false targets form the two-dimensional cover jamming or deception jamming, which can protect the important targets efficiently. The number of false targets, the interval of false targets, and the jamming square can be adjusted flexibly by setting different range jamming parameters and azimuth jamming parameters. The jamming performance and the choosing criteria of jamming parameters are also discussed. Finally, the simulated data verify the effectiveness of the jamming method. 展开更多
关键词 BISTATIC synthetic APERTURE RADAR (BiSAR) cosinusoidal phase COVER jamming MICRO-MOTION modulation
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The impact of rain to observed signal from Chinese Gaofen-3 synthetic aperture radar in typhoons 预览
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作者 Jian Shi Jiachen Hu +4 位作者 Weizeng Shao Xiaoqing Wang Xinzhe Yuan Liangbo Zhao Xiaofeng Li 《海洋学报:英文版》 SCIE CAS CSCD 2019年第11期121-133,共13页
Gaofen-3(GF-3),a Chinese civil synthetic aperture radar(SAR)at C-band,has operated since August 2016.Remarkably,several typhoons have been captured by GF-3 around the China Seas over its last two-year mission.In this ... Gaofen-3(GF-3),a Chinese civil synthetic aperture radar(SAR)at C-band,has operated since August 2016.Remarkably,several typhoons have been captured by GF-3 around the China Seas over its last two-year mission.In this study,six images acquired in Global Observation(GLO)and Wide ScanSAR(WSC)modes at verticalvertical(VV)polarization channel are discussed.This work focuses on investigating the observation of rainfall using GF-3 SAR.These images were collocated with winds from the European Centre for Medium-Range Weather Forecasts(ECMWF),significant wave height simulated from the WAVEWATCH-III(WW3)model,sea surface currents from climate forecast system version 2(CFSv2)of the National Centers for Environmental Prediction(NCEP)and rain rate data from the Tropical Rainfall Measuring Mission(TRMM)satellite.Sea surface roughness,was compared with the normalized radar cross section(NRCS)from SAR observations,and indicated a 0.8 correlation(COR).We analyzed the dependences of the difference between model-simulated NRCS and SARmeasured NRCS on the TRMM rain rate and WW3-simulated significant wave height.It was found that the effects of rain on SAR damps the radar signal at incidence angles ranging from 15°to 30°,while it enhances the radar signal at incidence angles ranging from 30°to 45°and incidence angles smaller than 10°.This behavior is consistent with previous studies and an algorithm for rain rate retrieval is anticipated for GF-3 SAR. 展开更多
关键词 Gaofen-3 synthetic aperture radar TYPHOON
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An accelerated nonlocal means algorithm for synthetic aperture radar ocean image despeckling 预览
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作者 Guozhen Zha Dewei Xu +2 位作者 Yanming Yang Xin’gai Song Fuhuang Zhong 《海洋学报:英文版》 SCIE CAS CSCD 2019年第11期140-148,共9页
Synthetic aperture radar(SAR)images play an increasingly important role in ocean environmental monitoring and research.However,SAR images are inherently corrupted by speckle noise.SAR ocean images have some unique cha... Synthetic aperture radar(SAR)images play an increasingly important role in ocean environmental monitoring and research.However,SAR images are inherently corrupted by speckle noise.SAR ocean images have some unique characteristics.The signatures of ocean phenomena in SAR images mainly exhibit as stripe or plaque shaped features.These features typically have a high degree of self-similarity or redundancy.The nonlocal means(NLM)method can measure the structural similarity between different image patches and take advantage of redundant information in images.Considering that the NLM algorithm is computationally intensive and timeconsuming,an accelerated NLM algorithm for SAR ocean image despeckling is proposed in this paper.A method is used to discriminate between texture and flat pixels in SAR images.Large similarity and search windows are used on texture pixels,whereas small similarity and search windows are used on flat pixels.Furthermore,the improved NLM algorithm is accelerated by a graphic processing unit(GPU)based on the compute unified device architecture(CUDA)parallel computation framework.The computational efficiency is improved by approximately 200 times. 展开更多
关键词 synthetic aperture radar speckle noise OCEAN nonlocal means method compute unified device architecture
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不同粒径条件下煤孔隙结构特征分析 预览
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作者 王福生 张志明 +1 位作者 孙超 王川 《工业安全与环保》 2019年第5期23-25,共3页
当前煤体孔隙结构研究普遍基于液氮吸附实验,而实验所测结果因选取煤样粒径的不同而变动。利用不同煤阶的5种煤样分别选取不同目数的煤样进行实验,测得了在不同粒径条件下的比表面积、平均孔径、吸附曲线等数据。研究表明,焦煤孔隙结构... 当前煤体孔隙结构研究普遍基于液氮吸附实验,而实验所测结果因选取煤样粒径的不同而变动。利用不同煤阶的5种煤样分别选取不同目数的煤样进行实验,测得了在不同粒径条件下的比表面积、平均孔径、吸附曲线等数据。研究表明,焦煤孔隙结构测试数据受实验样品粒径影响较大,褐煤平均孔径较大,孔隙发育程度高且测试数据受实验样品粒径影响较小。 展开更多
关键词 孔隙结构 液氮吸附 等温曲线 比表面积 孔径
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U型胶贴附、结构与材质及对背光源黑白影影响的研究 预览
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作者 李宗明 《电子测试》 2019年第7期63-64,共2页
使用真空吸附、U型胶打孔、U型胶条状设计、U型胶材质变化和真空吸附治具对U型胶贴附方法、孔径尺寸、条状数量尺寸及U型胶材质对U型胶贴附产生的黑白影不良的影响进行研究。研究结果表明:U型胶使用槽状U型胶固定治具进行贴附,能将U型... 使用真空吸附、U型胶打孔、U型胶条状设计、U型胶材质变化和真空吸附治具对U型胶贴附方法、孔径尺寸、条状数量尺寸及U型胶材质对U型胶贴附产生的黑白影不良的影响进行研究。研究结果表明:U型胶使用槽状U型胶固定治具进行贴附,能将U型胶的固定进度提升至0.5mm;U型胶使用槽状U型胶固定治具进行贴附,可以将贴附时间从11S降低到4.8S,作业效率提升约56%;U型胶的打孔设计改善无法克服背光源黑白影不良的产生;U型胶的条状胶体设计改善无法克服背光源黑白影不良的产生;U型胶材质变软可以解决U型胶贴附后黑白影不良的不良,不良率从18%降低到0%。 展开更多
关键词 U型胶 黑白影 真空治具 孔径 条状设计
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基于接触式传感器的制孔质量自动检测装置及研究 预览
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作者 曾超 孟华林 +1 位作者 王强 孙海龙 《航空制造技术》 2019年第19期99-102,共4页
飞机铆钉孔的质量对飞机可靠性和安全性至关重要,但铆钉孔的精度仍采用传统的手工方式进行检测,已 无法满足现代飞机对铆钉孔高精度的要求。通过研究基于接触式传感器的制孔质量自动检测装置,将接触式测头、 位移传感器等机械式测量工... 飞机铆钉孔的质量对飞机可靠性和安全性至关重要,但铆钉孔的精度仍采用传统的手工方式进行检测,已 无法满足现代飞机对铆钉孔高精度的要求。通过研究基于接触式传感器的制孔质量自动检测装置,将接触式测头、 位移传感器等机械式测量工具和控制与数据采集系统、数据处理软件等自动化软件结合到一起,实现了铆钉孔孔径、 孔深、锪窝深度和锪窝直径的一体化检测功能,提高了铆钉孔质量检测效率、精度和稳定性,对铆钉孔的接触式一体 化检测起到了很好的推动作用,具有良好的工程应用价值。 展开更多
关键词 接触式测头 位移传感器 自动检测 孔径 孔深 锪窝深度 锪窝直径
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High Resolution Radar Real-Time Signal and Information Processing 预览
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作者 Teng Long Tao Zeng +8 位作者 Cheng Hu Xichao Dong Liang Chen Quanhua Liu Yizhuang Xie Zegang Ding Yang Li Yanhua Wang Yan Wang 《中国通信:英文版》 SCIE CSCD 2019年第2期105-133,共29页
Radar is an electronic device that uses radio waves to determine the range,angle,or velocity of objects.Real-time signal and information processor is an important module for real-time positioning,imaging,detection and... Radar is an electronic device that uses radio waves to determine the range,angle,or velocity of objects.Real-time signal and information processor is an important module for real-time positioning,imaging,detection and recognition of targets.With the development of ultra-wideband technology,synthetic aperture technology,signal and information processing technology,the radar coverage,detection accuracy and resolution have been greatly improved,especially in terms of one-dimensional(1D)high-resolution radar detection,tracking,recognition,and two-dimensional(2D)synthetic aperture radar imaging technology.Meanwhile,for the application of radar detection and remote sensing with high resolution and wide swath,the amount of data has been greatly increased.Therefore,the radar is required to have low-latency and real-time processing capability under the constraints of size,weight and power consumption.This paper systematically introduces the new technology of high resolution radar and real-time signal and information processing.The key problems and solutions are discussed,including the detection and tracking of 1D high-resolution radar,the accurate signal modeling and wide-swath imaging for geosynchronous orbit synthetic aperture radar,and real-time signal and information processing architecture and efficient algorithms.Finally,the latest research progress and representative results are presented,and the development trends are prospected. 展开更多
关键词 1D high RESOLUTION RADAR geosynchronous SYNTHETIC APERTURE RADAR REAL-TIME SIGNAL and information processing
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煤层气自激振荡增产工具空化试验 预览
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作者 韩军 马勇 +2 位作者 郑杰 程嘉瑞 窦益华 《石油机械》 北大核心 2019年第9期111-117,共7页
为提高煤层气采收率,对煤层气自激振荡增产所用空化工具的内部结构进行了室内试验研究,得到了不同流量、孔径和进出口锥度下的节流压差,计算得出各结构及试验条件对应的空化数,进而反映各因素对空化效果的影响。研究结果表明:流量和孔... 为提高煤层气采收率,对煤层气自激振荡增产所用空化工具的内部结构进行了室内试验研究,得到了不同流量、孔径和进出口锥度下的节流压差,计算得出各结构及试验条件对应的空化数,进而反映各因素对空化效果的影响。研究结果表明:流量和孔径是影响空化的主要因素,流量与压差成正比,孔径与压差成反比,为了更容易产生空化,应减小孔径,增大流量;流量较小时空化数增加速率大于流量较大时空化数增加速率,孔板直径越小,空化效果越好;流量较大时,孔板直径对空化效果影响不大;采用一次节流(上结构)入口锥度1∶1、出口锥度1∶0.5以及二次节流(下结构)入口锥度1∶0.5,此时空化效果达到最优。研究结果对于煤层气井的增产技术研究具有一定的指导意义。 展开更多
关键词 煤层气 空化工具 流量 孔径 节流压差 出入口锥度 空化数
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Frequency Domain Filtering SAR Interferometric Phase Noise Using the Amended Matrix Pencil Model 预览
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作者 Yandong Gao Shubi Zhang +1 位作者 Kefei Zhang Shijin Li 《工程与科学中的计算机建模(英文)》 2019年第5期349-363,共15页
Interferometric phase filtering is one of the key steps in interferometricsynthetic aperture radar (InSAR/SAR). However, the ideal filtering results are difficult toobtain due to dense fringe and low coherence regions... Interferometric phase filtering is one of the key steps in interferometricsynthetic aperture radar (InSAR/SAR). However, the ideal filtering results are difficult toobtain due to dense fringe and low coherence regions. Moreover, the InSAR/SAR datarange is relatively large, so the efficiency of interferential phase filtering is one of themajor problems. In this letter, we proposed an interferometric phase filtering methodbased on an amended matrix pencil and linear window mean filter. The combination ofthe matrix pencil and the linear mean filter are introduced to the interferometric phasefiltering for the first time. First, the interferometric signal is analyzed, and theinterferometric phase filtering is transformed into a local frequency estimation problem.Then, the local frequency is estimated using an amended matrix pencil at a window. Thelocal frequency can represent terrain changes, thus suggesting that the frequency can beaccurately estimated even in dense fringe regions. Finally, the local frequency is filteredby using a linear window mean filter, and the filtered phase is recovered. The proposedmethod is calculated by some matrices. Therefore, the computational complexity isreduced, and the efficiency of the interferometric phase filtering is improved.Experiments are conducted with simulated and real InSAR data. The proposed methodexhibits a better filtering effect and an ideal efficiency as compared with the traditionalfiltering method. 展开更多
关键词 Interferometric phase filtering interferometric synthetic aperture radar local frequency estimation amended matrix pencil linear window mean filter
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Rapid growth and properties of large-aperture 98%-deuterated DKDP crystals
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作者 Xumin Cai Xiuqing Lin +3 位作者 Guohui Li Junye Lu Ziyu Hu Guozong Zheng 《高功率激光科学与工程:英文版》 CAS CSCD 2019年第3期87-94,共8页
In this paper,a highly deuterated potassium dihydrogen phosphate(DKDP)crystal with sizes up to 318 mm×312 mm×265 mm was grown by the rapid-growth method.The synthesis tank device was specially designed to sy... In this paper,a highly deuterated potassium dihydrogen phosphate(DKDP)crystal with sizes up to 318 mm×312 mm×265 mm was grown by the rapid-growth method.The synthesis tank device was specially designed to synthesize a higher deuterium concentration and high-purity DKDP solution.The deuterium content of the as-grown crystal,which was 97.9%,was determined by two methods,including infrared(IR)spectroscopy and thermo-gravimetric analysis(TGA)measurements.The performances of the 97.9%DKDP crystal,including transmission,absorption coefficient,and laserinduced damage threshold(LIDT)were measured.The results indicate that,in the near-infrared band,the transmission of the 97.9%DKDP crystal is higher than that of KDP and 70%DKDP crystals,and the absorption coefficient is lower.The LIDT of the crystal reached 23.2 J·cm^-2(R-on-1,1064 nm,3 ns),which meets the engineering requirements for use in optical applications. 展开更多
关键词 DKDP crystal large aperture highly deuterated DKDP rapid growth
光学系统设计中的光阑应用分析 预览
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作者 高爱梅 李星辰 王婷婷 《电子工业专用设备》 2019年第2期24-27,共4页
基于远心镜头、显微镜头等成像镜头的光学系统在半导体装备上应用非常广泛。光学系统设计中需要规定对一定成像范围内的物点,以要求孔径角成像,这些对成像光束起到约束作用的孔径称为光阑;依据作用不同,一般分为孔径光阑、视场光阑、渐... 基于远心镜头、显微镜头等成像镜头的光学系统在半导体装备上应用非常广泛。光学系统设计中需要规定对一定成像范围内的物点,以要求孔径角成像,这些对成像光束起到约束作用的孔径称为光阑;依据作用不同,一般分为孔径光阑、视场光阑、渐晕光阑和消杂散光阑;结合光学系统设计案例,深入分析了各类光阑对光学系统的影响。 展开更多
关键词 光阑 孔径 视场 渐晕 杂光
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机床基础件动态特性影响因素的研究及应用 预览
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作者 米洁 闫文飞 +1 位作者 杨庆东 张世珍 《制造技术与机床》 北大核心 2019年第12期46-49,共4页
对某加工中心的床身、立柱基础件进行建模,采用弹簧-阻尼单元法对连接的结合面进行处理,完成基础件的动态特性分析。根据得到的前6阶模态的振型及频率数值,找出结构设计中的薄弱环节,并提出改进意见。改变筋板单元孔孔径大小、布局密度... 对某加工中心的床身、立柱基础件进行建模,采用弹簧-阻尼单元法对连接的结合面进行处理,完成基础件的动态特性分析。根据得到的前6阶模态的振型及频率数值,找出结构设计中的薄弱环节,并提出改进意见。改变筋板单元孔孔径大小、布局密度、单元孔形状,分析不同筋板结构型式的床身、立柱的性能,获得影响基础件动态特性的参数变化规律,得出选择合适孔径数据、增加筋板布局密度,能有效提高基础件动态性能。所得结论具有工程应用推广价值,同时为机床基础件结构改进、设计优化提供理论依据。 展开更多
关键词 基础件 动态特性 影响因素 筋板 单元孔孔径 筋板布局密度 单元孔形状
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浅析车身内腔电泳效果改善 预览
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作者 王奇 史亚邦 +1 位作者 张存乐 杨晋 《上海涂料》 CAS 2019年第3期39-44,共6页
以车型内腔锈蚀问题进行逆推试验的方法,对车型腔体结构设计进行研究,对提升内腔部位电泳效果进行浅析,在SE设计阶段对车型问题进行规避,以缩短项目开发及后续问题整改周期、节省车型开发成本。
关键词 整车防腐 内腔电泳 孔径 距离关系
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Advanced technology of high-resolution radar: target detection, tracking, imaging, and recognition
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作者 Teng LONG Zhennan LIANG Quanhua LIU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第4期1-26,共26页
In recent years, the performances of radar resolution, coverage, and detection accuracy have been significantly improved through the use of ultra-wideband, synthetic aperture and digital signal processing technologies... In recent years, the performances of radar resolution, coverage, and detection accuracy have been significantly improved through the use of ultra-wideband, synthetic aperture and digital signal processing technologies. High-resolution radars (HRRs) utilize wideband signals and synthetic apertures to enhance the range and angular resolutions of tracking, respectively. They also generate one-, two-, and even threedimensional high-resolution images containing the feature information of targets, from which the targets can be precisely classified and identified. Advanced signal processing algorithms in HRRs obtain important information such as range-Doppler imaging, phase-derived ranging, and micro-motion features. However, the advantages and applications of HRRs are restricted by factors such as the reduced signal-to-noise ratio (SNR) of multi-scatter point targets, decreased tracking accuracy of multi-scatter point targets, high demands of motion compensation, and low sensitivity of the target attitude. Focusing on these problems, this paper systematically introduces the novel technologies of HRRs and discusses the issues and solutions relevant to detection, tracking, imaging, and recognition. Finally, it reviews the latest progress and representative results of HRR-based research, and suggests the future development of HRRs. 展开更多
关键词 HIGH-RESOLUTION RADAR integrated detection and TRACKING multiple target TRACKING phase-derived velocity inverse synthetic APERTURE radar(ISAR) hierarchical classification CONVOLUTION neural network
A novel visual attention method for target detection from SAR images
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作者 Fei GAO Aidong LIU +2 位作者 Kai LIU Erfu YANG Amir HUSSAIN 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第8期1946-1958,共13页
Synthetic Aperture Radar(SAR) imaging systems have been widely used in civil and military fields due to their all-weather and all-day abilities and various other advantages. However, due to image data exponentially in... Synthetic Aperture Radar(SAR) imaging systems have been widely used in civil and military fields due to their all-weather and all-day abilities and various other advantages. However, due to image data exponentially increasing, there is a need for novel automatic target detection and recognition technologies. In recent years, the visual attention mechanism in the visual system has helped humans effectively deal with complex visual signals. In particular, biologically inspired top-down attention models have garnered much attention recently. This paper presents a visual attention model for SAR target detection, comprising a bottom-up stage and top-down process.In the bottom-up step, the Itti model is improved based on the difference between SAR and optical images. The top-down step fully utilizes prior information to further detect targets. Extensive detection experiments carried out on the benchmark Moving and Stationary Target Acquisition and Recognition(MSTAR) dataset show that, compared with typical visual models and other popular detection methods, our model has increased ability and robustness for SAR target detection, under a range of Signal to Clutter Ratio(SCR) conditions and scenes. In addition, results obtained using only the bottom-up stage are inferior to those of the proposed method, further demonstrating the effectiveness and rationality of a top-down strategy. In summary, our proposed visual attention method can be considered a potential benchmark resource for the SAR research community. 展开更多
关键词 Learning strategy Synthetic APERTURE Radar(SAR) IMAGES Target detection TOP-DOWN Visual ATTENTION mechanism
Intertidal area classification with generalized extreme value distribution and Markov random field in quad-polarimetric synthetic aperture radar imagery
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作者 Ting-ting JIN Xiao-qiang SHE +1 位作者 Xiao-lan QIU Bin LEI 《信息与电子工程前沿:英文版》 SCIE EI CSCD 2019年第2期253-264,共12页
Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficult... Classification of intertidal area in synthetic aperture radar(SAR) images is an important yet challenging issue when considering the complicatedly and dramatically changing features of tidal fluctuation. The difficulty of intertidal area classification is compounded because a high proportion of this area is frequently flooded by water, making statistical modeling methods with spatial contextual information often ineffective. Because polarimetric entropy and anisotropy play significant roles in characterizing intertidal areas, in this paper we propose a novel unsupervised contextual classification algorithm. The key point of the method is to combine the generalized extreme value(GEV) statistical model of the polarization features and the Markov random field(MRF) for contextual smoothing. A goodness-of-fit test is added to determine the significance of the components of the statistical model. The final classification results are obtained by effectively combining the results of polarimetric entropy and anisotropy. Experimental results of the polarimetric data obtained by the Chinese Gaofen-3 SAR satellite demonstrate the feasibility and superiority of the proposed classification algorithm. 展开更多
关键词 INTERTIDAL CLASSIFICATION Polarimetric synthetic APERTURE radar Finite mixture MODEL MARKOV random field Generalized extreme value MODEL
基于钻孔图像的岩体结构面几何信息智能测量
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作者 葛云峰 钟鹏 +8 位作者 唐辉明 赵斌滨 王亮清 夏丁 仇雅诗 李鹏飞 张莉 闻炼 曹天赐 《岩土力学》 EI CAS CSCD 北大核心 2019年第11期4467-4476,共10页
针对钻孔图像中岩体结构面形态特征,提出了一种基于Canny检测的岩体结构面几何信息智能测量方法。该方法首先采用灰度共生矩阵特征参数,在长幅钻孔图像中定位结构面区域;然后,对识别的结构面区域,采用Canny检测算法识别出结构面边缘,并... 针对钻孔图像中岩体结构面形态特征,提出了一种基于Canny检测的岩体结构面几何信息智能测量方法。该方法首先采用灰度共生矩阵特征参数,在长幅钻孔图像中定位结构面区域;然后,对识别的结构面区域,采用Canny检测算法识别出结构面边缘,并通过边缘连接和合适的阈值筛选边缘,提取出结构面上下边缘;最后,对结构面边缘进行三角函数拟合,得到结构面上下边缘的正弦曲线,结合立体空间几何理论,从而计算出岩体结构面的倾向、倾角、隙宽等参数。以如美水电站坝址区两钻孔为例,基于本算法提取结构面几何信息,并与已有成功算法进行对比得到了较为一致的结果,证明了算法的可行性。 展开更多
关键词 岩体结构面 钻孔图像 Canny检测 灰度共生矩阵 结构面产状 结构面隙宽
Multi-baseline extended particle filtering phase unwrapping algorithm based on amended matrix pencil model and quantized path-following strategy 预览
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作者 XIE Xianming ZENG Qingning 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第1期78-84,共7页
This paper proposes a new multi-baseline extended particle filtering phase unwrapping algorithm which combines an extended particle filter with an amended matrix pencil model and a quantized path-following strategy. T... This paper proposes a new multi-baseline extended particle filtering phase unwrapping algorithm which combines an extended particle filter with an amended matrix pencil model and a quantized path-following strategy. The contributions to multibaseline synthetic aperture radar (SAR) interferometry are as follows: a new recursive multi-baseline phase unwrapping model based on an extended particle filter is built, and the amended matrix pencil model is used to acquire phase gradient information with a higher precision and lower computational cost, and the quantized path-following strategy is introduced to guide the proposed phase unwrapping procedure to efficiently unwrap wrapped phase image along the paths routed by a phase derivative variance map. 展开更多
关键词 multi-baseline phase unwrapping INTERFEROMETRIC synthetic APERTURE RADAR (InSAR) EXTENDED particle filter.
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