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Robust key point descriptor for multi-spectral image matching 被引量:3
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作者 Yueming Qin Zhiguo Cao +1 位作者 Wen Zhuo Zhenghong Yu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期681-687,共7页
Histogram of collinear gradient-enhanced coding (HCGEC), a robust key point descriptor for multi-spectral image matching, is proposed. The HCGEC mainly encodes rough structures within an image and suppresses detaile... Histogram of collinear gradient-enhanced coding (HCGEC), a robust key point descriptor for multi-spectral image matching, is proposed. The HCGEC mainly encodes rough structures within an image and suppresses detailed textural information, which is desirable in multi-spectral image matching. Experiments on two multi-spectral data sets demonstrate that the proposed descriptor can yield significantly better results than some state-of- the-art descriptors. 展开更多
关键词 collinear gradient-enhanced coding (CGEC) key pointdescriptor multi-spectral image matching.
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Investigation of Image Fusion Between High-Resolution Image and Multi-spectral Image 被引量:1
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作者 LI Pingxiang WANG ZhijunLI Pingxiang, professor, State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, 129 Luoyu Road, Wuhan 430079, China. 《Geo-Spatial Information Science》 2003年第2期31-34,共4页
On the basis of a thorough understanding of the physical characteristics of remote sensing image, this paper employs the theories of wavelet transform and signal sampling to develop a new image fusion algorithm. The a... On the basis of a thorough understanding of the physical characteristics of remote sensing image, this paper employs the theories of wavelet transform and signal sampling to develop a new image fusion algorithm. The algorithm has been successfully applied to the image fusion of SPOT PAN and TM of Guangdong province, China. The experimental results show that a perfect image fusion can be built up by using the image analytical solution and re-construction in the image frequency domain based on the physical characteristics of the image formation. The method has demonstrated that the results of the image fusion do not change spectral characteristics of the original image. 展开更多
关键词 image fusion remote sensing wavelet transform signal sampling
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Fusion of multi-spectral image and panchromatic image based on support vector regression
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作者 胡根生 梁栋 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期269-277,共9页
In our study, support vector value contourlet transform is constructed by using support vector regression model and directional filter banks. The transform is then used to decompose source images at multi-scale, multi... In our study, support vector value contourlet transform is constructed by using support vector regression model and directional filter banks. The transform is then used to decompose source images at multi-scale, multi-direction and multi-resolution. After that, the super-resolved multi-spectral image is reconstructed by utilizing the strong learning ability of support vector regression and the correlation between multi-spectral image and panchromatic image. Finally, the super-resolved multi- spectral image and the panchromatic image are fused based on regions at different levels. Our experi- ments show that, the learning method based on support vector regression can improve the effect of super-resolution of multi-spectral image. The fused image preserves both high space resolution and spectrum information of multi-spectral image. 展开更多
关键词 image processing image fusion support vector regression SUPER-RESOLUTION
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Multi-spectral image fusion method based on two channels non-separable wavelets 被引量:9
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作者 LIU Bin PENG JiaXiong 《Science in China(Series F)》 2008年第12期2022-2032,共11页
A construction method of two channels non-separable wavelets filter bank which dilation matrix is[1,1;1,-1]and its application in the fusion of multi-spectral image are presented.Many 4×4 filter banks are designe... A construction method of two channels non-separable wavelets filter bank which dilation matrix is[1,1;1,-1]and its application in the fusion of multi-spectral image are presented.Many 4×4 filter banks are designed.The multi-spectral image fusion algorithm based on this kind of wavelet is proposed.Using this filter bank,multi-resolution wavelet decomposition of the intensity of multi-spectral image and panchromatic image is performed,and the two low-frequency components of the intensity and the panchromatic image are merged by using a tradeoff parameter.The experiment results show that this method is good in the preservation of spectral quality and high spatial resolution information.Its performance in preserving spectral quality and high spatial information is better than the fusion method based on DWFT and IHS.When the parameter t is closed to 1,the fused image can obtain rich spectral information from the original MS image.The amount of computation reduced to only half of the fusion method based on four channels wavelet transform. 展开更多
关键词 image fusion non-separable wavelets multi-spectral image panchromatic image
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基于人工智能Precise Image重建算法对头颅CT图像质量及辐射剂量的影响
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作者 廖甜 刘晓静 +5 位作者 宁先英 桂绅 孔祥闯 雷子乔 余建明 吴红英 《放射学实践》 北大核心 2026年第1期66-71,共6页
目的:评估Precise Image人工智能重建算法对头颅CT图像质量及辐射剂量的影响。方法:回顾性搜集行头颅CT平扫的80例患者,A组(40例)采用120 kV、150 mAs采集图像,同时采用Precise Image(sharp/standard/smooth/smoother)算法、iDose 4等... 目的:评估Precise Image人工智能重建算法对头颅CT图像质量及辐射剂量的影响。方法:回顾性搜集行头颅CT平扫的80例患者,A组(40例)采用120 kV、150 mAs采集图像,同时采用Precise Image(sharp/standard/smooth/smoother)算法、iDose 4等级算法进行图像重建;B组(40例)采用传统轴扫方案采集图像(120 kV、250 mAs扫描条件),采用iDose 4等级算法进行图像重建。对比不同剂量、不同重建方式下头颅CT检查图像质量及辐射剂量。结果:A组较B组CTDIvol、DLP、SSDE分别降低约55.02%、42.68%、59.22%(P<0.05)。A组随着重建算法等级的升高(sharp、standard、smooth、smoother),小脑、背侧丘脑及灰白质噪声SD值下降,信号噪声比(SNR)、对比噪声比(CNR)升高,且均高于同扫描条件下iDose 4算法,除sharp算法外差异均有统计学意义(P<0.05)。A组standard、smooth算法主观评分为(4.63±0.49)分、(4.27±0.38)分,两组均满足诊断需求;B组主观评分为(4.52±0.41)分。结论:Precise Image人工智能重建算法在保证图像质量的前提下可大大降低头颅CT辐射剂量。 展开更多
关键词 体层摄影术 X线计算机 人工智能 Precise image 图像质量 辐射剂量
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Acquiring multi-spectral images by digital still cameras based on XYZLMS interim connection space 被引量:1
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作者 张显斗 王强 +1 位作者 杨根福 王萌萌 《Chinese Optics Letters》 SCIE EI CAS CSCD 2014年第11期129-132,共4页
A method based on the XYZLMS interim connection space is proposed to accurately acquire the multi-spectral images by digital still cameras. The XYZLMS values are firstly predicted from RGB values by polynomial model w... A method based on the XYZLMS interim connection space is proposed to accurately acquire the multi-spectral images by digital still cameras. The XYZLMS values are firstly predicted from RGB values by polynomial model with local training samples and then spectral reflectance is constructed from XYZLMS values by pseudo-inverse method. An experiment is implemented for multi-spectral image acquisition based on a commercial digital still camera. The results indicate that multi-spectral images can be accurately acquired except the very dark colors. 展开更多
关键词 RGB Acquiring multi-spectral images by digital still cameras based on XYZLMS interim connection space LUT
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Precision organoid segmentation technique(POST):accurate organoid segmentation in challenging bright-field images 被引量:1
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作者 Xuan Du Yuchen Li +5 位作者 Jiaping Song Zilin Zhang Jing Zhang Yanhui Li Zaozao Chen Zhongze Gu 《Bio-Design and Manufacturing》 2026年第1期80-93,I0013-I0016,共18页
Organoids possess immense potential for unraveling the intricate functions of human tissues and facilitating preclinical disease treatment.Their applications span from high-throughput drug screening to the modeling of... Organoids possess immense potential for unraveling the intricate functions of human tissues and facilitating preclinical disease treatment.Their applications span from high-throughput drug screening to the modeling of complex diseases,with some even achieving clinical translation.Changes in the overall size,shape,boundary,and other morphological features of organoids provide a noninvasive method for assessing organoid drug sensitivity.However,the precise segmentation of organoids in bright-field microscopy images is made difficult by the complexity of the organoid morphology and interference,including overlapping organoids,bubbles,dust particles,and cell fragments.This paper introduces the precision organoid segmentation technique(POST),which is a deep-learning algorithm for segmenting challenging organoids under simple bright-field imaging conditions.Unlike existing methods,POST accurately segments each organoid and eliminates various artifacts encountered during organoid culturing and imaging.Furthermore,it is sensitive to and aligns with measurements of organoid activity in drug sensitivity experiments.POST is expected to be a valuable tool for drug screening using organoids owing to its capability of automatically and rapidly eliminating interfering substances and thereby streamlining the organoid analysis and drug screening process. 展开更多
关键词 Organoid Drug screening Deep learning image segmentation
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Multi-Scale Transformer for Image Restoration
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作者 Wuzhen Shi Youwei Pan +4 位作者 Chun Zhao Yuqing Liu Shaobo Zhang Heng Zhang Yang Wen 《CAAI Transactions on Intelligence Technology》 2026年第1期41-54,共14页
Although Transformer-based image restoration methods have demonstrated impressive performance,existing Transformers still insufficiently exploit multiscale information.Previous non-Transformer-based studies have shown... Although Transformer-based image restoration methods have demonstrated impressive performance,existing Transformers still insufficiently exploit multiscale information.Previous non-Transformer-based studies have shown that incorporating multiscale features is crucial for improving restoration results.In this paper,we propose a multiscale Transformer(MST)that captures cross-scale attention among tokens,thereby effectively leveraging the multiscale patch recurrence prior of natural images.Furthermore,we introduce a channel-gate feed-forward network(CGFN)to enhance inter-channel information aggregation and reduce channel redundancy.To simultaneously utilise global,local and multiscale features,we design a multitype feature integration block(MFIB).Extensive experiments on both image super-resolution and HEVC compressed video artefact reduction demonstrate that the proposed MST achieves state-of-the-art performance.Ablation studies further verify the effectiveness of each proposed module. 展开更多
关键词 computer vision image enhancement image processing image reconstruction image resolution
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Underwater Image Enhancement Based on Depthwise Separable Convolution-Based Generative Adversarial Network
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作者 ZENG Jun-yang SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2026年第1期60-66,共7页
The existence of absorption and reflection of light underwater leads to problems such as color distortion and blue-green bias in underwater images.In this study,a depthwise separable convolution-based generative adver... The existence of absorption and reflection of light underwater leads to problems such as color distortion and blue-green bias in underwater images.In this study,a depthwise separable convolution-based generative adversarial network(GAN)algorithm was proposed.Taking GAN as the basic framework,it combined a depthwise separable convolution module,attention mechanism,and reconstructed convolution module to realize the enhancement of underwater degraded images.Multi-scale features were captured by the depthwise separable convolution module,and the attention mechanism was utilized to enhance attention to important features.The reconstructed convolution module further extracts and fuses local and global features.Experimental results showed that the algorithm performs well in improving the color bias and blurring of underwater images,with PSNR reaching 27.835,SSIM reaching 0.883,UIQM reaching 3.205,and UCIQE reaching 0.713.The enhanced image outperforms the comparison algorithm in both subjective and objective metrics. 展开更多
关键词 Underwater image enhancement Generating adversarial network Depthwise separable convolution
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A multi-attention mechanism U-Net neural network for image correction of PbS quantum dot focal plane detectors
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作者 WANG Han-Ting DI Yun-Xiang +10 位作者 QI Xing-Yu SHA Ying-Zhe WANG Ya-Hui YE Ling-Feng TANG Wei-Yi BA Kun WANG Xu-Dong HUANG Zhang-Cheng CHU Jun-Hao SHEN Hong WANG Jian-Lu 《红外与毫米波学报》 北大核心 2026年第1期148-156,共9页
Near-infrared image sensors are widely used in fields such as material identification,machine vision,and autonomous driving.Lead sulfide colloidal quantum dot-based infrared photodiodes can be integrated with sil⁃icon... Near-infrared image sensors are widely used in fields such as material identification,machine vision,and autonomous driving.Lead sulfide colloidal quantum dot-based infrared photodiodes can be integrated with sil⁃icon-based readout circuits in a single step.Based on this,we propose a photodiode based on an n-i-p structure,which removes the buffer layer and further simplifies the manufacturing process of quantum dot image sensors,thus reducing manufacturing costs.Additionally,for the noise complexity in quantum dot image sensors when capturing images,traditional denoising and non-uniformity methods often do not achieve optimal denoising re⁃sults.For the noise and stripe-type non-uniformity commonly encountered in infrared quantum dot detector imag⁃es,a network architecture has been developed that incorporates multiple key modules.This network combines channel attention and spatial attention mechanisms,dynamically adjusting the importance of feature maps to en⁃hance the ability to distinguish between noise and details.Meanwhile,the residual dense feature fusion module further improves the network's ability to process complex image structures through hierarchical feature extraction and fusion.Furthermore,the pyramid pooling module effectively captures information at different scales,improv⁃ing the network's multi-scale feature representation ability.Through the collaborative effect of these modules,the network can better handle various mixed noise and image non-uniformity issues.Experimental results show that it outperforms the traditional U-Net network in denoising and image correction tasks. 展开更多
关键词 PbS quantum dot focal plane detector convolutional neural networks image denoising U-Net
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FDEFusion:End-to-End Infrared and Visible Image Fusion Method Based on Frequency Decomposition and Enhancement
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作者 Ming Chen Guoqiang Ma +3 位作者 Ping Qi Fucheng Wang Lin Shen Xiaoya Pi 《Computers, Materials & Continua》 2026年第4期817-839,共23页
In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,eff... In the image fusion field,fusing infrared images(IRIs)and visible images(VIs)excelled is a key area.The differences between IRIs and VIs make it challenging to fuse both types into a high-quality image.Accordingly,efficiently combining the advantages of both images while overcoming their shortcomings is necessary.To handle this challenge,we developed an end-to-end IRI andVI fusionmethod based on frequency decomposition and enhancement.By applying concepts from frequency domain analysis,we used the layering mechanism to better capture the salient thermal targets from the IRIs and the rich textural information from the VIs,respectively,significantly boosting the image fusion quality and effectiveness.In addition,the backbone network combined Restormer Blocks and Dense Blocks;Restormer blocks utilize global attention to extract shallow features.Meanwhile,Dense Blocks ensure the integration between shallow and deep features,thereby avoiding the loss of shallow attributes.Extensive experiments on TNO and MSRS datasets demonstrated that the suggested method achieved state-of-the-art(SOTA)performance in various metrics:Entropy(EN),Mutual Information(MI),Standard Deviation(SD),The Structural Similarity Index Measure(SSIM),Fusion quality(Qabf),MI of the pixel(FMI_(pixel)),and modified Visual Information Fidelity(VIF_(m)). 展开更多
关键词 Infrared images visible images frequency decomposition restormer blocks global attention
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Advances in deep learning for bacterial image segmentation in optical microscopy
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作者 Zhijun Tan Yang Ding +6 位作者 Huibin Ma Jintao Li Danrou Zheng Hua Bai Weini Xin Lin Li Bo Peng 《Journal of Innovative Optical Health Sciences》 2026年第1期30-44,共15页
Microscopy imaging is fundamental in analyzing bacterial morphology and dynamics,offering critical insights into bacterial physiology and pathogenicity.Image segmentation techniques enable quantitative analysis of bac... Microscopy imaging is fundamental in analyzing bacterial morphology and dynamics,offering critical insights into bacterial physiology and pathogenicity.Image segmentation techniques enable quantitative analysis of bacterial structures,facilitating precise measurement of morphological variations and population behaviors at single-cell resolution.This paper reviews advancements in bacterial image segmentation,emphasizing the shift from traditional thresholding and watershed methods to deep learning-driven approaches.Convolutional neural networks(CNNs),U-Net architectures,and three-dimensional(3D)frameworks excel at segmenting dense biofilms and resolving antibiotic-induced morphological changes.These methods combine automated feature extraction with physics-informed postprocessing.Despite progress,challenges persist in computational efficiency,cross-species generalizability,and integration with multimodal experimental workflows.Future progress will depend on improving model robustness across species and imaging modalities,integrating multimodal data for phenotype-function mapping,and developing standard pipelines that link computational tools with clinical diagnostics.These innovations will expand microbial phenotyping beyond structural analysis,enabling deeper insights into bacterial physiology and ecological interactions. 展开更多
关键词 Bacterial image deep learning optical microscopy image segmentation artificial intelligence
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Clinical information prompt-driven retinal fundus image for brain health evaluation
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作者 Nuo Tong Ying Hui +10 位作者 Shui-Ping Gou Ling-Xi Chen Xiang-Hong Wang Shuo-Hua Chen Jing Li Xiao-Shuai Li Yun-Tao Wu Shou-Ling Wu Zhen-Chang Wang Jing Sun Han Lv 《Military Medical Research》 2026年第1期43-57,共15页
Background:Brain volume measurement serves as a critical approach for assessing brain health status.Considering the close biological connection between the eyes and brain,this study aims to investigate the feasibility... Background:Brain volume measurement serves as a critical approach for assessing brain health status.Considering the close biological connection between the eyes and brain,this study aims to investigate the feasibility of estimating brain volume through retinal fundus imaging integrated with clinical metadata,and to offer a cost-effective approach for assessing brain health.Methods:Based on clinical information,retinal fundus images,and neuroimaging data derived from a multicenter,population-based cohort study,the Kai Luan Study,we proposed a cross-modal correlation representation(CMCR)network to elucidate the intricate co-degenerative relationships between the eyes and brain for 755 subjects.Specifically,individual clinical information,which has been followed up for as long as 12 years,was encoded as a prompt to enhance the accuracy of brain volume estimation.Independent internal validation and external validation were performed to assess the robustness of the proposed model.Root mean square error(RMSE),peak signal-tonoise ratio(PSNR),and structural similarity index measure(SSIM)metrics were employed to quantitatively evaluate the quality of synthetic brain images derived from retinal imaging data.Results:The proposed framework yielded average RMSE,PSNR,and SSIM values of 98.23,35.78 d B,and 0.64,respectively,which significantly outperformed 5 other methods:multi-channel Variational Autoencoder(mcVAE),Pixelto-Pixel(Pixel2pixel),transformer-based U-Net(Trans UNet),multi-scale transformer network(MT-Net),and residual vision transformer(ResViT).The two-(2D)and three-dimensional(3D)visualization results showed that the shape and texture of the synthetic brain images generated by the proposed method most closely resembled those of actual brain images.Thus,the CMCR framework accurately captured the latent structural correlations between the fundus and the brain.The average difference between predicted and actual brain volumes was 61.36 cm~3,with a relative error of 4.54%.When all of the clinical information(including age and sex,daily habits,cardiovascular factors,metabolic factors,and inflammatory factors)was encoded,the difference was decreased to 53.89 cm~3,with a relative error of 3.98%.Based on the synthesized brain magnetic resonance images from retinal fundus images,the volumes of brain tissues could be estimated with high accuracy.Conclusion:This study provides an innovative,accurate,and cost-effective approach to characterize brain health status through readily accessible retinal fundus images. 展开更多
关键词 Retinal fundus image Brain volume Brain health Magnetic resonance imaging Deep learning Eye and brain connection
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人工智能如何更好地促进人类文明发展?——从Image、Concept到Sign的重大跨越
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作者 许晓东 《长沙理工大学学报(社会科学版)》 2026年第2期47-56,共10页
人工智能的爆发式发展本质是现代启蒙理性的极致延伸,其技术演进遵循Image、Concept、Sign的分化逻辑。文章以《启蒙辩证法》为核心理论工具,紧扣理性与权力相互渗透、启蒙双重视角、文明三阶段等核心观点,系统分析人工智能从数据图像... 人工智能的爆发式发展本质是现代启蒙理性的极致延伸,其技术演进遵循Image、Concept、Sign的分化逻辑。文章以《启蒙辩证法》为核心理论工具,紧扣理性与权力相互渗透、启蒙双重视角、文明三阶段等核心观点,系统分析人工智能从数据图像的抽象化、算法概念的工具化,到符号体系的支配化的跨越演进过程。人工智能的发展潜力,既源于启蒙理性对世界的祛魅与重构能力,也内含启蒙自我消解的风险。工具理性的单向强化、权力对技术的裹挟导致图像与符号的彻底分离,技术理性沦为新的支配性意识形态。只有回归《启蒙辩证法》的批判维度,重构理性的双重内涵、消解符号对现实的异化、解构技术权力的垄断格局,才能让人工智能摆脱技术极权主义风险,成为服务人类文明的积极力量。 展开更多
关键词 人工智能 《启蒙辩证法》 image—Concept—Sign 工具理性 技术批判
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RE-UKAN:A Medical Image Segmentation Network Based on Residual Network and Efficient Local Attention
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作者 Bo Li Jie Jia +2 位作者 Peiwen Tan Xinyan Chen Dongjin Li 《Computers, Materials & Continua》 2026年第3期2184-2200,共17页
Medical image segmentation is of critical importance in the domain of contemporary medical imaging.However,U-Net and its variants exhibit limitations in capturing complex nonlinear patterns and global contextual infor... Medical image segmentation is of critical importance in the domain of contemporary medical imaging.However,U-Net and its variants exhibit limitations in capturing complex nonlinear patterns and global contextual information.Although the subsequent U-KAN model enhances nonlinear representation capabilities,it still faces challenges such as gradient vanishing during deep network training and spatial detail loss during feature downsampling,resulting in insufficient segmentation accuracy for edge structures and minute lesions.To address these challenges,this paper proposes the RE-UKAN model,which innovatively improves upon U-KAN.Firstly,a residual network is introduced into the encoder to effectively mitigate gradient vanishing through cross-layer identity mappings,thus enhancing modelling capabilities for complex pathological structures.Secondly,Efficient Local Attention(ELA)is integrated to suppress spatial detail loss during downsampling,thereby improving the perception of edge structures and minute lesions.Experimental results on four public datasets demonstrate that RE-UKAN outperforms existing medical image segmentation methods across multiple evaluation metrics,with particularly outstanding performance on the TN-SCUI 2020 dataset,achieving IoU of 88.18%and Dice of 93.57%.Compared to the baseline model,it achieves improvements of 3.05%and 1.72%,respectively.These results fully demonstrate RE-UKAN’s superior detail retention capability and boundary recognition accuracy in complex medical image segmentation tasks,providing a reliable solution for clinical precision segmentation. 展开更多
关键词 image segmentation U-KAN residual network ELA
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The Construction of Ouyang Xiu's Posthumous Image in the Song Dynasty
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作者 Yang Xiangkui Wang Minhan 《Contemporary Social Sciences》 2026年第1期18-34,共17页
The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song D... The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song Dynasty,writings by Ouyang Xiu's family and epitaphs by his colleagues crafted a balanced narrative emphasizing both his official duties and literary merits,thus constructing a dual image of him as a principled remonstrator and a literary master.In the Southern Song Dynasty,official historiography gradually eroded his complex persona as a political reformer by selectively trimming political disputes and emphasizing his literary lineage,ultimately establishing him as a cultural exemplar beyond factional strife.Throughout this evolution of historical writing,Ouyang Xiu's sharpness as a remonstrator was gradually obscured in historical texts,while his image as a literary master,revered by all,became firmly established.The reshaping of Ouyang Xiu's image in historical writings across the Northern and Southern Song dynasties not only reflects the logic of selecting scholar-official role models under the influence of official ideology but also reveals the inherent pattern whereby individual distinctiveness fades into symbolic construction in historical writing. 展开更多
关键词 Ouyang Xiu image construction biographical writing canonization
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Multi-Feature Fragile Image Watermarking Algorithm for Tampering Blind-Detection and Content Self-Recovery
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作者 Qiuling Wu Hao Li +1 位作者 Mingjian Li Ming Wang 《Computers, Materials & Continua》 2026年第1期759-778,共20页
Digital watermarking technology plays an important role in detecting malicious tampering and protecting image copyright.However,in practical applications,this technology faces various problems such as severe image dis... Digital watermarking technology plays an important role in detecting malicious tampering and protecting image copyright.However,in practical applications,this technology faces various problems such as severe image distortion,inaccurate localization of the tampered regions,and difficulty in recovering content.Given these shortcomings,a fragile image watermarking algorithm for tampering blind-detection and content self-recovery is proposed.The multi-feature watermarking authentication code(AC)is constructed using texture feature of local binary patterns(LBP),direct coefficient of discrete cosine transform(DCT)and contrast feature of gray level co-occurrence matrix(GLCM)for detecting the tampered region,and the recovery code(RC)is designed according to the average grayscale value of pixels in image blocks for recovering the tampered content.Optimal pixel adjustment process(OPAP)and least significant bit(LSB)algorithms are used to embed the recovery code and authentication code into the image in a staggered manner.When detecting the integrity of the image,the authentication code comparison method and threshold judgment method are used to perform two rounds of tampering detection on the image and blindly recover the tampered content.Experimental results show that this algorithm has good transparency,strong and blind detection,and self-recovery performance against four types of malicious attacks and some conventional signal processing operations.When resisting copy-paste,text addition,cropping and vector quantization under the tampering rate(TR)10%,the average tampering detection rate is up to 94.09%,and the peak signal-to-noise ratio(PSNR)of the watermarked image and the recovered image are both greater than 41.47 and 40.31 dB,which demonstrates its excellent advantages compared with other related algorithms in recent years. 展开更多
关键词 Fragile image watermark tampering blind-detection SELF-RECOVERY multi-feature
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Design of a compact wide-field-of-view infrared imager based on wavefront coding
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作者 Chonghui Zhu Jiaqian Yu Jingang Cui 《Chinese Physics B》 2026年第2期383-388,共6页
Compact size,high brightness,and wide field of view(FOV)are key requirements for long-wave infrared imagers used in military surveillance or night navigation.However,to meet the imaging requirements of high resolution... Compact size,high brightness,and wide field of view(FOV)are key requirements for long-wave infrared imagers used in military surveillance or night navigation.However,to meet the imaging requirements of high resolution and wide FOV,infrared optical systems often adopt complex optical lens groups,which will increase the size and weight of the optical system.In this paper,a strategy based on wavefront coding(WFC)is proposed to design a compact wide-FOV infrared imager.A cubic phase mask is inserted into the pupil plane of the infrared imager to correct the aberration.The simulated results show that,the WFC infrared imager has good imaging quality in a wide FOV of±16°.In addition,the WFC infrared imager achieves compactness with its 40 mm×40 mm×40 mm size.A fast focal ratio of 1 combined with an entrance pupil diameter of 25 mm ensures brightness.This work is of significance for designing a compact wide-FOV infrared imager. 展开更多
关键词 optical design infrared imager wavefront coding
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Image-free single-pixel semantic segmentation for complex scene based on multi-scale U-Net
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作者 Tengfei Liu Yanfeng Bai +4 位作者 Jianxia Chen Jintao Zhai Siqing Xiang Xianwei Huang Xiquan Fu 《Chinese Physics B》 2026年第1期440-447,共8页
Single-pixel imaging(SPI)receives widespread attention due to its superior anti-interference capabilities,and image segmentation technology can effectively facilitate its recognition and information extraction.However... Single-pixel imaging(SPI)receives widespread attention due to its superior anti-interference capabilities,and image segmentation technology can effectively facilitate its recognition and information extraction.However,the complexity of the target scene and plenty of imaging time in SPI make it challenging to achieve high-quality and concise segmentation.In this paper,we investigate the image-free intricate scene semantic segmentation in SPI.Using“learned”illumination patterns allows for the full extraction of the object's spatial information,thereby enabling pixel-level segmentation results through the decoding of the received measurements.Simulation and experimentation show that,in the absence of image reconstruction,the mean intersection over union(MIoU)of segmented image can reach higher than 85%,and the Dice coefficient(DICE)close to 90%even at the sampling ratio of 5%.Our approach may be favorable to applications in medical image segmentation and autonomous driving field. 展开更多
关键词 single-pixel imaging image-free deep learning complex scene
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Tracing equatorward and poleward boundaries of the magnetospheric cusp from a simulated X-ray image
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作者 Xue Wang TianRan Sun +4 位作者 C.Philippe Escoubet Andy Read YiHong Guo Steve Sembay Chi Wang 《Earth and Planetary Physics》 2026年第1期144-155,共12页
A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-d... A large-scale view of the magnetospheric cusp is expected to be obtained by the Soft X-ray Imager(SXI)onboard the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE).However,it is challenging to trace the three-dimensional cusp boundary from a two-dimensional X-ray image because the detected X-ray signals will be integrated along the line of sight.In this work,a global magnetohydrodynamic code was used to simulate the X-ray images and photon count images,assuming an interplanetary magnetic field with a pure Bz component.The assumption of an elliptic cusp boundary at a given altitude was used to trace the equatorward and poleward boundaries of the cusp from a simulated X-ray image.The average discrepancy was less than 0.1 RE.To reduce the influence of instrument effects and cosmic X-ray backgrounds,image denoising was considered before applying the method above to SXI photon count images.The cusp boundaries were reasonably reconstructed from the noisy X-ray image. 展开更多
关键词 SMILE mission X-ray image cusp boundary
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