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Transported into the Bosom of the Empire? Rethinking How Arthur Conan Doyle Persuades His Readers of British Imperialism in "The Speckled Band"
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作者 Billy Bin Feng Huang 《Journalism and Mass Communication》 2015年第4期194-205,共12页
Melanie C.Green and Timothy C.Brock have proposed their transportation-imagery model of narrative persuasion.They argue that a narrative can evoke imagery in readers'mind and then transport readers into the narrat... Melanie C.Green and Timothy C.Brock have proposed their transportation-imagery model of narrative persuasion.They argue that a narrative can evoke imagery in readers'mind and then transport readers into the narrative world the author has created,in the course of which the author can persuade readers of the beliefs he's put into the narrative.This paper employs this model to rethink how Arthur Conan Doyle persuades his readers of British imperialism in his"The Speckled Band".First,this model considers the vividness of the narrative and readers'participatory response as key factors in readers'transportation.The narratives of"The Speckled Band"are picturesque,and Sherlock Holmes'inferential process has reinforced readers'participatory response.On the other hand,detective fiction usually has the theme of how the detective/law and order beats the criminal/chaos.That is,Doyle persuades his readers that the British Empire will prevail in"The Speckled Band"when Holmes,representing the British imperialism,solves the case and kills Dr.Roylott,who represents the evil and savagery in the British colony.According to Green and Brock's model,it simply means that there are two narratives(i.e.,one is about how the law of the British Empire is challenged,and the other is about how the British Empire's stability is restored),and two complementary transportations before Doyle can successfully persuades his readers.However,if we closely read"'The Speckled Band",we can learn that Holmes,who should have represented British law,is guilty of trespassing or taking the law into his own hands.In other words,the complementarity of the two transportations is compromised.Thus,we can conclude that it is highly questionable whether or not Doyle can transport his readers into the bosom of the British Empire. 展开更多
关键词 Arthur Conan Doyle "The speckled Band" transport(ation) narrative persuade(-sion) Britishimperialism
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Harnessing speckle images:efficient extraction of hidden information
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作者 Weiru Fan Xiaobin Tang +5 位作者 Xingqi Xu Huizhu Hu Vladislav V.Yakovlev Shi-Yao Zhu Da-Wei Wang Delong Zhang 《Advanced Photonics Nexus》 2026年第1期211-223,共13页
Scattering obscures information carried by waves by producing speckle patterns,posing a fundamental challenge across diverse fields,from microscopy to astronomy.Although machine learning has recently shown promise in ... Scattering obscures information carried by waves by producing speckle patterns,posing a fundamental challenge across diverse fields,from microscopy to astronomy.Although machine learning has recently shown promise in speckle analysis,existing approaches are hindered by their dependence on large,labeled datasets—a significant bottleneck in many real-world applications.Here,we introduce speckle unsupervised recognition and evaluation(SURE),a groundbreaking unsupervised learning strategy for speckle recognition that eliminates the need for labeled training data.SURE's distinctive feature lies in its ability to extract invariant features through advanced clustering algorithms to enable direct classification of high-level information from speckle patterns without prior knowledge.We demonstrate the transformative potential of this approach in two key applications:(1)a noninvasive glucose monitoring system that accurately tracks glucose concentrations over time without extensive calibration and(2)a high-throughput communication system using multimode fibers,achieving improved performance in dynamic environments.In addition,we showcase SURE's unprecedented capability to classify objects hidden behind obstacles using scattered light,further broadening its scope.This versatile approach opens new frontiers in biomedical diagnostics,quantum network decoupling,and remote sensing,unlocking a transformative new paradigm for extracting information from seemingly random optical patterns. 展开更多
关键词 SCATTERING unsupervised learning speckle interpretation pattern recognition image sensing
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High-speed all-optical speckle decryption empowered by a physics-informed diffractive neural network
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作者 Jiaan Gan Yong Yang +2 位作者 Siwei Zhu Shengjiang Chang Xiaocong Yuan 《Advanced Photonics Nexus》 2026年第1期150-157,共8页
Speckle-based optical cryptosystems are promising technologies for information security.However,existing techniques mostly rely on digital decryption,resulting in computational delay and undermining the high-speed adv... Speckle-based optical cryptosystems are promising technologies for information security.However,existing techniques mostly rely on digital decryption,resulting in computational delay and undermining the high-speed advantage of optical encryption.Moreover,conventional neural networks are typically effective only on images from the same distribution as the training datasets,limiting their general applicability.In this paper,we propose an all-optical high-speed decryption scheme for real-time recovery of speckle-encoded ciphertexts.By constructing a physics-informed diffractive neural network that approximates the inverse transmission matrix of the scattering medium,secret images can be directly reconstructed from speckle fields without optoelectronic conversion or post-processing.The network is trained with only 2048 samples from the MNIST dataset.Its transfer learning capability is validated across three out-of-distribution datasets,with decrypted images achieving a Pearson correlation coefficient of 0.82 and a structural similarity index measure of 0.75,demonstrating excellent transfer learning capability.For the first time,to our knowledge,this scheme simultaneously overcomes the bottlenecks of decryption delay and limited network generalizability in conventional speckle-based cryptosystems,achieving real-time image decryption with strong transferability.It provides a new pathway for developing low-power,real-time,and broadly applicable optical encryption systems,demonstrating significant potential for applications in high-speed security optical communications. 展开更多
关键词 SPECKLE all-optical decryption diffractive neural network transmission matrix transfer learning real time
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Temporal Variability Analysis of Cortical Blood Flow in Rats with Hyperacute Cerebral Ischemia
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作者 Bochao Niu Benjamin Klugah-Brown +2 位作者 Yang Xia Dezhong Yao Bharat B.Biswal 《Neuroscience Bulletin》 2026年第1期55-74,共20页
Cerebral ischemia restricts cerebral blood flow(CBF),leading to unstable hemodynamics.Past studies of ischemia mainly focused on cortical CBF reduction.However,its impact on hemodynamic changes,especially temporal var... Cerebral ischemia restricts cerebral blood flow(CBF),leading to unstable hemodynamics.Past studies of ischemia mainly focused on cortical CBF reduction.However,its impact on hemodynamic changes,especially temporal varying characteristics,remains poorly understood.Here,we collected cortical resting-state CBF in rats with left carotid artery blockage during occlusion–reperfusion,and measured the temporal variability and changes in laterality using a novel state-space method.This method was also applied to stroke EEG datasets to validate its effectiveness.After arterial occlusion,the left marginal motor,sensory,auditory,and visual cortices exhibited severe temporal variability impairments.The laterality analysis indicated that affected left regions showed inferior unilateral mean,inter-hemispheric transition probability,time fraction,and laterality duration,while the right side had a higher laterality time fraction and duration.These impairments recovered partially following blood flow restoration.Besides,the ischemic state-space metrics were positively correlated with the pre-occlusion baseline appearance.Stroke patients exhibited impaired temporal variability in the affected ischemic hemisphere.The state-space analysis revealed damaged CBF temporal variability during cerebral ischemia and predicted baseline-ischemia connections. 展开更多
关键词 STATE-SPACE Cerebral blood flow Cerebral ischemia Laser speckle contrast imaging Temporal variability
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Fabrication of silicone vascular phantoms using chewy candy as a dissolvable core material:Feasibility study
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作者 Hyunseon Yu Chanyoung Kim +1 位作者 Donghwan Ko Byungjo Jung 《Journal of Innovative Optical Health Sciences》 2026年第2期44-53,共10页
This study aims to develop a novel,cost-effective method for fabricating silicone vascular phantoms(SVPs)using"chewy candy"as a dissolvable core material.The study explores the feasibility of using chewy can... This study aims to develop a novel,cost-effective method for fabricating silicone vascular phantoms(SVPs)using"chewy candy"as a dissolvable core material.The study explores the feasibility of using chewy candy to create detailed and intricate vascular models for clinical applications.The chewy candy,an amorphous material,was manually extruded to form vascular models of varying diameters.These models were embedded in a silicone mixture,which was then cured.The chewy candy was subsequently dissolved,leaving behind hollow silicone vascular channels.The SVPs were evaluated for their morphological accuracy and functionality through laser speckle contrast imaging.The SVPs successfully replicated vascular channels with consistent diameters,demonstrating minimal variation across different regions.Functional evaluation using laser speckle contrast imaging revealed distinct flow dynamics in Y-shaped and H-shaped SVPs,highlighting the potential for these phantoms to simulate realistic fluid dynamics in vascular systems.This study presents a simple,time-saving,and innovative approach to fabricating complex 3D SVPs using chewy candy.This method offers a viable alternative to traditional fabrication techniques,with potential applications in various biomedical fields. 展开更多
关键词 Silicone vascular phantom chewy candy amorphous material optical imaging fluid dynamics laser speckle contrast imaging
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Full-color and less-speckled modified Gerchberg–Saxton algorithm computer-generated hologram floating in a dual-parabolic projection system 被引量:5
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作者 陳建宇 張軒庭 +1 位作者 張琮然 莊智皓 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第11期24-27,共4页
This Letter proposes to apply full-color computer-generated holograms to the virtual image projection system so that the viewers can comfortably view floating images. Regarding the spatial division and distribution op... This Letter proposes to apply full-color computer-generated holograms to the virtual image projection system so that the viewers can comfortably view floating images. Regarding the spatial division and distribution operation,a modified Gerchberg–Saxton algorithm is used for acquiring the phase infographics, which are input into the spatial light modulator for the reconstructed projection. Such a virtual image projection system could reach the vertical angle of view of 15°–75° and the horizontal angle of view 360°, and the mixed-light modulating proportion contains a 3 m W red light laser, a 2 m W green light laser, and a 2.6 m W blue light laser to achieve the full-color mixed-light proportion with a speckle contrast of 6.65%. The relative diffraction efficiency and root mean square error of the reconstructed image are 95.3% and 0.0524, respectively. 展开更多
关键词 PROJECTION FLOATING reconstructed SPECKLE modulato
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The role of SRPK1-mediated phosphorylation of SR proteins in the chromatin configuration transition of mouse germinal vesicle oocytes 被引量:1
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作者 Xia Wang Shuai Zhou +8 位作者 Haojie Yin Jian Han Yue Hu Siqi Wang Congjing Wang Jie Huang Junqiang Zhang Xiufeng Ling Ran Huo 《Journal of Biomedical Research》 2025年第2期198-208,I0013-I0015,共14页
Meiotic resumption in mammalian oocytes involves nuclear and organelle structural changes,notably the chromatin configuration transition from a non-surrounding nucleolus(NSN)to surrounding nucleolus(SN)in germinal ves... Meiotic resumption in mammalian oocytes involves nuclear and organelle structural changes,notably the chromatin configuration transition from a non-surrounding nucleolus(NSN)to surrounding nucleolus(SN)in germinal vesicle oocytes.In the current study,we found that nuclear speckles(NSs),a subnuclear structure mainly composed of serine-arginine(SR)proteins,changed from a diffuse spotted distribution in mouse NSN oocytes to an aggregated pattern in SN oocytes.We also found that the SR protein-specific kinase 1(SRPK1),an enzyme that phosphorylates SR proteins,co-localized with NSs at the SN stage,and that NSN oocytes failed to transition to SN oocytes after the inhibition of SRPK1 activity.Furthermore,the typical structure of the chromatin ring around the nucleolus in SN oocytes collapsed after treatment with an SRPK1 inhibitor.Mechanistically,phosphorylated SR proteins were found to be related to chromatin as shown by a salt extraction experiment,and in situ DNaseⅠassay showed that the accessibility of chromatin was enhanced in SN oocytes when SRPK1 was inhibited,accompanied by a decreased repressive modification on histone and the abnormal recurrence of a transcriptional signal.In conclusion,our results indicated that SRPK1-regulated phosphorylation of SR proteins was involved in the NSN-SN transition and played an important role in maintaining the condensed nucleus of SN oocytes via interacting with chromatin. 展开更多
关键词 OOCYTE CHROMATIN nuclear speckle SR protein PHOSPHORYLATION SRPK1
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Speckle Transformer:direct classification through scattering media with limited information
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作者 Qi Zhao Zhiyuan Wang +7 位作者 Zhipeng Yu Tianting Zhong Haoran Li Shengfu Cheng Haofan Huang Chi Man Woo Huanhao Li Puxiang Lai 《Advanced Photonics Nexus》 2025年第5期175-182,共8页
Retrieving high-fidelity images from optical speckles remains challenging,especially when the information in speckles is severely insufficient.To address classification through scattering media under such constraints,... Retrieving high-fidelity images from optical speckles remains challenging,especially when the information in speckles is severely insufficient.To address classification through scattering media under such constraints,we propose Speckle Transformer,a vision-transformer-based model that directly classifies objects using raw speckle patterns without intermediate image retrieval.By leveraging inherent features within speckles to extract discriminative features,our approach achieves nearly 90%accuracy for classifying speckles encoded with different images,outperforming traditional retrieval-classification pipelines by up to five times,even with extreme information sparsity(i.e.,1/1024 speckle regions of interest).In addition,we quantify speckle information capacity via information entropy analysis,demonstrating that classification accuracy correlates strongly with the information entropy of speckle autocorrelation.We not only overcome limitations of conventional methods but also establish a paradigm for real-time classification in scattering environments with constrained data. 展开更多
关键词 optical speckles scattering media CLASSIFICATION deep learning information entropy
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Impact of free electron laser coherence on imaging quality
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作者 Shuang Wei Shuang Gong +1 位作者 Yang Bu Zi-Jian Song 《Chinese Physics B》 2025年第5期385-397,共13页
The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and ... The high temporal and spatial coherence of free electron lasers(FELs)reduces the uniformity of the illumination field,leading to scattering effects that blur the edges of patterns,resulting in diminished accuracy and clarity.Traditional imaging models regard the light source as fully incoherent,making it difficult to assess the impact of partially coherent light fields on imaging.If FELs are used in imaging systems,their coherence must be considered.To address this issue,this study explores the relationship between coherence,imaging quality and speckle contrast through a simulation method based on random phases.The method divides the light beam into temporal and spatial coherence cells,analyzes their interactions,and simulates imaging results under different coherence conditions.Additionally,speckle patterns for various illumination modes are calculated to evaluate their effects on speckle contrast and illumination uniformity.The results indicate that under different illumination modes,illumination uniformity decreases as coherence increases,while speckle contrast increases with higher coherence.In terms of imaging quality,higher coherence leads to an increase in both line edge roughness(LER)and line width roughness(LWR),thereby reducing the imaging quality.Additionally,the narrower the line width,the greater the impact of coherence on the imaging quality,resulting in poorer imaging performance. 展开更多
关键词 free electron laser COHERENCE IMAGING speckle contrast field uniformity
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Light-sheet dynamic scattering imaging of microscopic blood flow
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作者 Kai Long Keertana Vinod Ram +4 位作者 Shuhao Shen E Du Ziheng Ren Zhiyuan Gong Nanguang Chen 《Advanced Photonics Nexus》 2025年第1期9-19,共11页
Microcirculation imaging is crucial in understanding the function and health of various tissues and organs.However,conventional imaging methods suffer from fluorescence label dependency,lack of depth resolution,and qu... Microcirculation imaging is crucial in understanding the function and health of various tissues and organs.However,conventional imaging methods suffer from fluorescence label dependency,lack of depth resolution,and quantification inaccuracy.Here,we report a light-sheet dynamic light-scattering imaging(LSHDSI)system to overcome these shortcomings.LSH-DSI utilizes selected plane illumination for an optical sectioning,while a time-frequency analysis method retrieves blood flow velocity estimates from dynamic changes in the detected light intensity.We have performed imaging experiments with zebrafish embryos to obtain angiographs from the trunk and head regions.The results show that LSH-DSI can capture label-free tomographic images of microvasculature and three-dimensional quantitative maps of local blood flow velocities. 展开更多
关键词 light sheet laser speckle imaging flow quantitative map tomographic imaging.
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Design, setup, and facilitation of the speckle structured illumination endoscopic system
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作者 Elizabeth Abraham Zhaowei Liu 《Opto-Electronic Science》 2025年第3期17-28,共12页
Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the... Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the last two decades.However,when translated to endoscopic systems,severe deformations of illumination patterns occur due to the large depth of field(DOF)and the 3D nature of the targets,introducing significant implementation challenges.Hence,this study explores a speckle-based system that best suits endoscopic practices to enhance image resolution by using random illumination patterns.The study presents a prototypic model of an endoscopic add-on,its design,and fabrication facilitated by using the speckle structured illumination endoscopic(SSIE)system.The imaging results of the SSIE are explained on a colon phantom model at different imaging planes with a wide field of view(FOV)and DOF.The obtained imaging metrics are elucidated and compared with state-of-the-art(SOA)high-resolution endoscopic techniques.Moreover,the potential for a clinical translation of the prototypic SSIE model is also explored in this work.The incorporation of the add-on and its subsequent results on the colon phantom model could potentially pave the way for its successful integration and use in futuristic clinical endoscopic trials. 展开更多
关键词 speckle imaging endoscopic add-on colon phantom clinical translation
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High-performance laser speckle contrast image vascular segmentation without delicate pseudo-label reliance
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作者 Shenglan Yao Huiling Wu +8 位作者 Suzhong Fu Shuting Ling Kun Wang Hongqin Yang Yaqin He Xiaolan Ma Xiaofeng Ye Xiaofei Wen Qingliang Zhao 《Journal of Innovative Optical Health Sciences》 2025年第1期117-133,共17页
Laser speckle contrast imaging(LSCI)is a noninvasive,label-free technique that allows real-time investigation of the microcirculation situation of biological tissue.High-quality microvascular segmentation is critical ... Laser speckle contrast imaging(LSCI)is a noninvasive,label-free technique that allows real-time investigation of the microcirculation situation of biological tissue.High-quality microvascular segmentation is critical for analyzing and evaluating vascular morphology and blood flow dynamics.However,achieving high-quality vessel segmentation has always been a challenge due to the cost and complexity of label data acquisition and the irregular vascular morphology.In addition,supervised learning methods heavily rely on high-quality labels for accurate segmentation results,which often necessitate extensive labeling efforts.Here,we propose a novel approach LSWDP for high-performance real-time vessel segmentation that utilizes low-quality pseudo-labels for nonmatched training without relying on a substantial number of intricate labels and image pairing.Furthermore,we demonstrate that our method is more robust and effective in mitigating performance degradation than traditional segmentation approaches on diverse style data sets,even when confronted with unfamiliar data.Importantly,the dice similarity coefficient exceeded 85%in a rat experiment.Our study has the potential to efficiently segment and evaluate blood vessels in both normal and disease situations.This would greatly benefit future research in life and medicine. 展开更多
关键词 Biomedical imaging laser speckle contrast imaging vessel segmentation weakly supervised learning MICROCIRCULATION
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Customizing the field of view for imaging through scattering media
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作者 Dajiang Lu Juncheng Chen +4 位作者 Yibin Tian Jiapeng Cai Zaoxin Chen Xiang Peng Wenqi He 《Advanced Photonics Nexus》 2025年第6期29-44,共16页
Noninvasive speckle autocorrelation is a promising technique for single-shot optical imaging through scattering media.However,it fails to image multiple distinct targets within an object space through scattering media... Noninvasive speckle autocorrelation is a promising technique for single-shot optical imaging through scattering media.However,it fails to image multiple distinct targets within an object space through scattering media because it is constrained by the tiny effective range of the optical memory effect.We present a method for multi-object single-shot imaging through scattering media that incorporates deep learning into the speckle autocorrelation technique,wherein the field of view(FOV)is customized by recovered autocorrelation sidelobes,and a conventional phase-retrieval algorithm is applied to a complete set of expected speckle autocorrelations to identify multiple target objects and their relative positions.Experiments verify the feasibility of customizing the FOV for imaging through scattering media.Image reconstruction results show that the proposed approach produces superior image quality compared to existing methods.We also demonstrate its generalization capability across different object types and unknown scattering media. 展开更多
关键词 scattering imaging speckle autocorrelation inverse problem
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海洋SAR图像小波Speckle滤波及边缘信息提取 被引量:10
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作者 郭子祺 卢刚 +1 位作者 王超 潘广东 《遥感学报》 EI CSCD 北大核心 2001年第6期428-433,T002,共7页
以海洋SAR图像的speckle滤波和边缘信息提取为研究目标 ,构造了以低通带通窄和时域冲击响应系数分布呈左右对称为特征的小波滤波器。这些特征使该小波滤波器在处理突变信号方面具有优良的特性。应用该小波滤波器 ,采用Wiener滤波算法 ,... 以海洋SAR图像的speckle滤波和边缘信息提取为研究目标 ,构造了以低通带通窄和时域冲击响应系数分布呈左右对称为特征的小波滤波器。这些特征使该小波滤波器在处理突变信号方面具有优良的特性。应用该小波滤波器 ,采用Wiener滤波算法 ,对海洋SAR图像进行了speckle滤波及采用Prewitt算子对边缘信息进行提取。用几种经典小波基函数采用相同的滤波算法和边缘增强算子进行了处理 ,并将它们的结果进行了对比分析。结果表明 ,虽然小波基函数在用于speckle滤波方面 ,稍逊其它几种经典小波基函数 ,但是在边缘信息保留方面 ,效果要明显优于其他小波基函数。 展开更多
关键词 SAR图像 speckle滤波 边缘提取 海洋 小波滤波器 噪斑信号 突变信号
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一种基于相对标准差的SAR图像Speckle滤波方法 被引量:13
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作者 徐新 廖明生 卜方玲 《遥感学报》 EI CSCD 2000年第3期214-218,共5页
通过分析SAR影像的Speckle局部统计特性和现有的空间滤波算法 ,提出了一种新的Speckle滤波方法 ,该方法以局部相对标准差为主要依据 ,采用特殊的滤波窗口邻域划分方法 ,自适应地调整窗口尺寸和窗口内的滤波区域。该方法被用于多幅ERS 1/... 通过分析SAR影像的Speckle局部统计特性和现有的空间滤波算法 ,提出了一种新的Speckle滤波方法 ,该方法以局部相对标准差为主要依据 ,采用特殊的滤波窗口邻域划分方法 ,自适应地调整窗口尺寸和窗口内的滤波区域。该方法被用于多幅ERS 1/ 2SAR图像去Speckle处理 ,并与以往的典型算法进行了比较实验 ,取得了令人满意的结果。 展开更多
关键词 相对标准差 遥感图像 SAR图像 Speckle滤波
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一种改进的SAR图像边缘检测方法 被引量:6
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作者 吕毅 孙洪 +2 位作者 曹永锋 王青 徐戈 《武汉大学学报(理学版)》 CAS CSCD 北大核心 2003年第1期107-111,共5页
针对Ratio边缘提取算法对弱边缘检测效果差 ,边缘定位精度低的缺点 ,提出了一种改进算法用于检测微弱边缘 ,并给出具有CFAR特性的阈值选取办法 实际应用中 ,将两种方法结合为一种综合处理方法 ,对真实SAR图像的处理结果表明 。
关键词 SAR图像 合成孔径雷达 Speckle噪声 边缘检测 图像处理 雷达图像 边缘算子
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小波软阈值算法去除SAR图像中的Speckle噪声 被引量:11
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作者 池明旻 卢刚 +1 位作者 黄盛璋 李郁 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第6期756-758,共3页
在详细分析了Donoho小波软阈值的基础上 ,应用小波变换技术对SAR图像进行分析处理 .使用“小波局部软阈值算法”来计算阈值 ,对高频小波系数进行阈值确定 .求得估计小波系数 ,对其取小波反变换后 ,去除SAR图像中的Speckle噪声 .实验结... 在详细分析了Donoho小波软阈值的基础上 ,应用小波变换技术对SAR图像进行分析处理 .使用“小波局部软阈值算法”来计算阈值 ,对高频小波系数进行阈值确定 .求得估计小波系数 ,对其取小波反变换后 ,去除SAR图像中的Speckle噪声 .实验结果表明此方法对去除Speckle噪声十分有效 。 展开更多
关键词 小波软阈值算法 SAR图像 Speckle噪声 小波变换 图像去噪 边缘检测 合成孔径雷达
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Microtubule Structure and Male Sterility in a Gene-Cytoplasmic Male Sterile Line of Rice, Zhen Shan 97A 被引量:4
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作者 叶秀麟 杨子德 +1 位作者 徐是雄 梁承邺 《Acta Botanica Sinica》 CSCD 2003年第2期183-192,共10页
Histological changes that occur during microsporogenesis are documented in a gene-cytoplasmic male sterile rice ( Oryza saliva L.) line, Zhen Shan 97A, its maintainer line, Zhen Shan 97B, and the restorer line, Ce64 o... Histological changes that occur during microsporogenesis are documented in a gene-cytoplasmic male sterile rice ( Oryza saliva L.) line, Zhen Shan 97A, its maintainer line, Zhen Shan 97B, and the restorer line, Ce64 of a Mine hybrid rice production system. In the restorer line, Ce64, the developing microsporocytes have dense cytoplasm and a distinct set of circumferential microtubules around the nucleus. Successive cytokinesis results in the formation of tetrads. The microtubules within the cells of tetrads and microspores radiate from the surface of the nucleus towards the outer edge of the cytoplasm. Subsequent pollen development is normal. During the course of microspore formation tubulin speckles can be found in the cytoplasm. The general pattern of development and microtubule organization in the maintainer lined Zhen Shan 97B, is similar to Ce64, except that a few more tubulin speckles appear during microspore formation. In the case of the mate sterile line, Zhen Shan 97A, a number of abnormalities can be discerned during early microsporogenesis. These include vacuoles forming within the developing microsporocyte and faintly stained microtubules with no defined distribution pattern. Prominent tubulin speckles are common within the cytoplasm. For those microsporocytes that undergo meiosis, no defined organizational patterns of microtubules can be found within the tetrad. All microspores abort soon after. Abnormalities and defects in microtubule organization observed in Zhen Shan 97A showed that complex interactions between the cytoplasm and the nucleus began at very early stage of microsporocyte development. 展开更多
关键词 Oryza saliva cytoplasmic male sterility microtubules microsporocyte VACUOLE tubulin speckles
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基于自适应邻域的超声图像加权中值滤波 被引量:2
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作者 朱其刚 刘明 +1 位作者 尹艳芳 曹茂永 《中国生物医学工程学报》 EI CAS CSCD 北大核心 2005年第2期186-188,共3页
提出了一种自适应邻域中值滤波算法 ,用于医学超声内窥镜图像的噪声滤除。该方法以图像象素邻域的灰度方差为阈值 ,进行保持与修复窗口的自适应改变 ,在有效抑制Speckle噪声的同时 ,较好保留了图像的细节信息。对本算法与Loupas提出的... 提出了一种自适应邻域中值滤波算法 ,用于医学超声内窥镜图像的噪声滤除。该方法以图像象素邻域的灰度方差为阈值 ,进行保持与修复窗口的自适应改变 ,在有效抑制Speckle噪声的同时 ,较好保留了图像的细节信息。对本算法与Loupas提出的加权中值滤波算法进行了比较 ,指出本算法在一定程度上克服了加权中值滤波器的不足并保留了它的优点 ,对超声内窥镜图像的滤噪有较好的效果。 展开更多
关键词 Speckle噪声 自适应中值滤波 超声内窥镜图像
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基于CxImage库的SAR图像Speckle噪声抑制 被引量:1
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作者 陈海花 张亮 陈鹏 《电子科技》 2013年第7期54-58,共5页
合成孔径雷达图像的相干斑噪声抑制是SAR信息处理中的一个重要环节。经典的Speckle噪声抑制通常作为一个处理模块集成在软件中,但现有软件代码封装无法二次开发。针对文中提出了一种基于开源图像库CxImage的空间域自适应Speckle噪声抑... 合成孔径雷达图像的相干斑噪声抑制是SAR信息处理中的一个重要环节。经典的Speckle噪声抑制通常作为一个处理模块集成在软件中,但现有软件代码封装无法二次开发。针对文中提出了一种基于开源图像库CxImage的空间域自适应Speckle噪声抑制算法的应用与集成。将CxImage图像库链接入MFC应用程序框架中,利用其图像管理、维护、处理功能对SAR图像进行维护管理,集成多种经典的空间域自适应滤波方法,并以ERS-2卫星的PRISAR数据为例,进行Speckle噪声滤波处理,选取适当的滤波效果评价参数,对滤波结果进行比较,最终得出各滤波算法应用于SAR图像滤波的优劣。 展开更多
关键词 遥感信息处理 SAR Speckle噪声 Cximage库
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