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CCLNet:An End-to-End Lightweight Network for Small-Target Forest Fire Detection in UAV Imagery
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作者 Qian Yu Gui Zhang +4 位作者 Ying Wang Xin Wu Jiangshu Xiao Wenbing Kuang Juan Zhang 《Computers, Materials & Continua》 2026年第3期1381-1400,共20页
Detecting small forest fire targets in unmanned aerial vehicle(UAV)images is difficult,as flames typically cover only a very limited portion of the visual scene.This study proposes Context-guided Compact Lightweight N... Detecting small forest fire targets in unmanned aerial vehicle(UAV)images is difficult,as flames typically cover only a very limited portion of the visual scene.This study proposes Context-guided Compact Lightweight Network(CCLNet),an end-to-end lightweight model designed to detect small forest fire targets while ensuring efficient inference on devices with constrained computational resources.CCLNet employs a three-stage network architecture.Its key components include three modules.C3F-Convolutional Gated Linear Unit(C3F-CGLU)performs selective local feature extraction while preserving fine-grained high-frequency flame details.Context-Guided Feature Fusion Module(CGFM)replaces plain concatenation with triplet-attention interactions to emphasize subtle flame patterns.Lightweight Shared Convolution with Separated Batch Normalization Detection(LSCSBD)reduces parameters through separated batch normalization while maintaining scale-specific statistics.We build TF-11K,an 11,139-image dataset combining 9139 self-collected UAV images from subtropical forests and 2000 re-annotated frames from the FLAME dataset.On TF-11K,CCLNet attains 85.8%mAP@0.5,45.5%mean Average Precision(mAP)@[0.5:0.95],87.4%precision,and 79.1%recall with 2.21 M parameters and 5.7 Giga Floating-point Operations Per Second(GFLOPs).The ablation study confirms that each module contributes to both accuracy and efficiency.Cross-dataset evaluation on DFS yields 77.5%mAP@0.5 and 42.3%mAP@[0.5:0.95],indicating good generalization to unseen scenes.These results suggest that CCLNet offers a practical balance between accuracy and speed for small-target forest fire monitoring with UAVs. 展开更多
关键词 Forest fire detection lightweight convolutional neural network UAV images small-target detection CCLNet
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Integration of Landsat and MODIS Imagery for Mapping 30-m Cotton Cultivation Areas in Xinjiang,China from 2000 to 2020
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作者 TAN Zhuting TAN Zhenyu +1 位作者 DUAN Hongtao ZHANG Kaili 《Chinese Geographical Science》 2026年第1期97-108,I0001,共13页
Cotton is an important global cash crops that serve as the primary source of natural fiber for textiles.A thorough understand-ing of the long-term variations in cotton cultivation is vital for optimizing cotton cultiv... Cotton is an important global cash crops that serve as the primary source of natural fiber for textiles.A thorough understand-ing of the long-term variations in cotton cultivation is vital for optimizing cotton cultivation management and promoting the sustainable development of the cotton industry.Xinjiang is the primary cotton-producing region in China.However,long-term data of cotton cultiv-ation areas with high spatial resolution are unavailable for Xinjiang,China.Therefore,this study aimed to identify and map an accurate 30-m cotton cultivation area dataset in Xinjiang from 2000 to 2020 by applying a Random Forest(RF)-based method that integrates Landsat and Moderate Resolution Imaging Spectroradiometer(MODIS)images,and validated the applicability and accuracy of dataset at a large spatial scale.Then,this study analyzed the spatiotemporal variations and influencing factors of cotton cultivation in the study period.The results showed that a high classification accuracy was achieved(overall accuracy>85%,F1>0.80),strongly agreeing with county-level agricultural statistical yearbook data(R2>0.72).Significant spatiotemporal variation in the cotton cultivation areas was found in Xinjiang,with a total increase of 1131.26 kha from 2000 to 2020.Notably,cotton cultivation area in southern Xinjiang expan-ded substantially,with that in Aksu increasing from 20.10%in 2000 to 28.17%in 2020,representing an expansion of 374.29 kha.In northern Xinjiang,the cotton areas in the Tacheng region also exhibited significant increased by almost ten percentage points in the same period.In contrast,cotton cultivation in eastern Xinjiang declined,decreasing from 2.22%in 2000 to merely 0.24%in 2020.Standard deviation ellipse analysis revealed a‘northeast-southwest’spatial distribution,with the centroid consistently located in Aksu and shifting 102.96 km over the 20-yr period.Pearson correlation analysis indicated that socioeconomic factors had a stronger influence on cotton cultivation than climatic factors,with effective irrigation area(r=0.963,P<0.05)and total agricultural machinery power(r=0.823)showing significant positive correlations,whereas climatic variables exhibiting weak associations(r<0.200).These results provide valuable scientific data for informed agricultural management,sustainable development,and policymaking. 展开更多
关键词 cotton cultivation mapping long-term series LANDSAT Moderate Resolution Imaging Spectroradiometer(MODIS) remote sensing Xinjiang China
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基于寒旱指数(CASI)的中国寒旱农业气候资源分布特征
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作者 王莺 张强 +2 位作者 孙芸 姚玉璧 冯新媛 《地球科学进展》 北大核心 2025年第9期961-973,共13页
寒旱区占我国国土面积一半以上,气候条件限制了该地区的农业发展。为充分挖掘农业气候资源优势,探索因地制宜的农业发展路径,亟须科学认识寒旱农业气候资源分布特征与其内在特质。基于2000—2020年高分辨率气象数据,融合热量限制与水分... 寒旱区占我国国土面积一半以上,气候条件限制了该地区的农业发展。为充分挖掘农业气候资源优势,探索因地制宜的农业发展路径,亟须科学认识寒旱农业气候资源分布特征与其内在特质。基于2000—2020年高分辨率气象数据,融合热量限制与水分胁迫构建了寒旱指数,量化了中国寒旱农业气候区空间格局及主导因子。研究发现,寒旱农业气候区占我国国土面积的16.42%,呈东北—西南带状分布。依据寒旱指数可划分为5个等级,其中青藏高原属极端胁迫区(一级),河西走廊与内蒙古高原为典型的农牧交错区(二、三级),东北平原至陇中一带水热配置最优,是适宜规模化发展的核心潜力区(四、五级)。甘肃和内蒙古的寒旱区面积占比超过40%,过渡地带表现出较高的气候敏感性。空间聚集分析进一步揭示,28.52%的区域为低值聚集区,是核心优势产区;28.24%的区域属高值聚集区,构成农业气候高风险带。因子贡献量分析显示,水分胁迫主导的区域占73%,热量限制主导的区域占27%,且寒贡献率随海拔升高显著增加。构建的寒旱指数体系为寒旱农业气候区划提供了新方法论工具,其区划成果可为优化农业空间布局、促进资源精准配置及发展特色产业提供科学依据。 展开更多
关键词 寒旱农业 气候区划 寒旱指数(casi) 聚集模式 因子贡献量
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Improving Image Quality of the Solar Disk Imager(SDI)of the LyαSolar Telescope(LST)Onboard the ASO-S Mission 被引量:1
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作者 Hui Liu Hui Li +11 位作者 Sizhong Zou Kaifan Ji Zhenyu Jin Jiahui Shan Jingwei Li Guanglu Shi Yu Huang Li Feng Jianchao Xue Qiao Li Dechao Song Ying Li 《Research in Astronomy and Astrophysics》 2025年第2期36-45,共10页
The in-flight calibration and performance of the Solar Disk Imager(SDI),which is a pivotal instrument of the LyαSolar Telescope onboard the Advanced Space-based Solar Observatory mission,suggested a much lower spatia... The in-flight calibration and performance of the Solar Disk Imager(SDI),which is a pivotal instrument of the LyαSolar Telescope onboard the Advanced Space-based Solar Observatory mission,suggested a much lower spatial resolution than expected.In this paper,we developed the SDI point-spread function(PSF)and Image Bivariate Optimization Algorithm(SPIBOA)to improve the quality of SDI images.The bivariate optimization method smartly combines deep learning with optical system modeling.Despite the lack of information about the real image taken by SDI and the optical system function,this algorithm effectively estimates the PSF of the SDI imaging system directly from a large sample of observational data.We use the estimated PSF to conduct deconvolution correction to observed SDI images,and the resulting images show that the spatial resolution after correction has increased by a factor of more than three with respect to the observed ones.Meanwhile,our method also significantly reduces the inherent noise in the observed SDI images.The SPIBOA has now been successfully integrated into the routine SDI data processing,providing important support for the scientific studies based on the data.The development and application of SPIBOA also paves new ways to identify astronomical telescope systems and enhance observational image quality.Some essential factors and precautions in applying the SPIBOA method are also discussed. 展开更多
关键词 techniques:image processing Sun:chromosphere Sun:flares methods:numerical
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Snapshot multispectral imaging through defocusing and a Fourier imager network
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作者 Xilin Yang Michael John Fanous +6 位作者 Hanlong Chen Ryan Lee Paloma Casteleiro Costa Yuhang Li Luzhe Huang Yijie Zhang Aydogan Ozcan 《Advanced Photonics Nexus》 2025年第5期24-35,共12页
Multispectral imaging,which simultaneously captures the spatial and spectral information of a scene,is widely used across diverse fields,including remote sensing,biomedical imaging,and agricultural monitoring.We intro... Multispectral imaging,which simultaneously captures the spatial and spectral information of a scene,is widely used across diverse fields,including remote sensing,biomedical imaging,and agricultural monitoring.We introduce a snapshot multispectral imaging approach employing a standard monochrome image sensor with no additional spectral filters or customized components.Our system leverages the inherent chromatic aberration of wavelength-dependent defocusing as a natural source of physical encoding of multispectral information;this encoded image information is rapidly decoded via a deep learning-based multispectral Fourier imager network(mFIN).We experimentally tested our method with six illumination bands and demonstrated an overall accuracy of 98.25%for predicting the illumination channels at the input and achieved a robust multispectral image reconstruction on various test objects.This deep learning-powered framework achieves high-quality multispectral image reconstruction using snapshot image acquisition with a monochrome image sensor and could be useful for applications in biomedicine,industrial quality control,and agriculture,among others. 展开更多
关键词 computational imaging multispectral imaging deep learning image reconstruction Fourier imager network
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RASI:the Robotic All-Sky narrowband Imager
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作者 Yuxin Xin Baoli Lun +6 位作者 Zejun Hu Yue Zhong Kai Ye Hongying Xu Yufeng Fan Bin Li Dehong Huang 《Astronomical Techniques and Instruments》 2025年第6期348-357,共10页
We report a new standalone Robotic All-Sky narrowband Imager(RASI)for auroral and airglow studies.RASI has new optics and an electromechanical system,low operation and installation costs,easy deployment and fully auto... We report a new standalone Robotic All-Sky narrowband Imager(RASI)for auroral and airglow studies.RASI has new optics and an electromechanical system,low operation and installation costs,easy deployment and fully automatic features.The new optics provide an all-sky field of view with excellent image quality and sensitivity.The new electromechanical system design offers a more compact size and the capability for outdoor independent deployment.We have also developed a fully automatic data acquisition software for RASI,which is based on the perception of solar altitude and the all-sky cloud cover.In conclusion,the RASI demonstrates significant advantages over the traditional all-sky narrowband imager,and it is highly suitable for the intensity measurements of large-scale auroras and airglow distributions. 展开更多
关键词 ROBOTIC All-sky imager AURORAS AIRGLOW Optical imaging
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Skin tone bias in online psoriasis imagery:Insights from an international study
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作者 Aman Sandhu Sanya Ailani +4 位作者 Smitesh Padte Priyal Mehta Neha Deo Salim Surani Rahul Kashyap 《World Journal of Clinical Cases》 2025年第36期6-12,共7页
BACKGROUND Psoriasis is often first recognized by patients through online image searches.However,search engine algorithms influenced by geographic location may still produce results that predominantly feature lighter ... BACKGROUND Psoriasis is often first recognized by patients through online image searches.However,search engine algorithms influenced by geographic location may still produce results that predominantly feature lighter skin tones,regardless of the region’s majority skin type.This underrepresentation may limit recognition and delay care for people of color.AIM To examine whether search algorithms tailor region-specific results in terms of skin color for psoriasis imagery.METHODS This observational study recruited 66 participants from 18 countries who conducted image searches for“psoriasis”across various web browsers.During the meeting,a Google form was posted to record observations,and participants reported the diversity of skin tones in the first three rows of search results using a reference image depicting Fitzpatrick types.RESULTS Results showed a global bias toward lighter skin tones,with 94%of participants identifying light skin predominance in the first row and minimal representation of medium or darker skin tones in subsequent results,verified via χ^(2) analysis.Participants who observed darker or mixed skin tones typically found them further down their results.CONCLUSION There remains a significant gap in global representation of psoriasis imagery.This paper deepens the current understanding of bias in online media and pushes for further exploration of more inclusive dermatologic imagery. 展开更多
关键词 PSORIASIS Internet Skin tone bias Image search Global
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On Translation Strategies for the Grass Imagery in Classical Chinese Poetry:A Cultural Semiotic Perspective
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作者 REN Rui LI Yutong SUN Yujingjing 《Sino-US English Teaching》 2025年第2期42-47,共6页
Grass constitutes a vital poetic imagery in classical Chinese poetry,embodying multifaceted symbolic connotations ranging from the tenacity of life to sentiments of separation and nostalgic longing.The translation of ... Grass constitutes a vital poetic imagery in classical Chinese poetry,embodying multifaceted symbolic connotations ranging from the tenacity of life to sentiments of separation and nostalgic longing.The translation of this botanical motif necessitates not merely lexical equivalence,but more importantly,the transmission of its profound cultural resonance and aesthetic essence.This study posits that effective rendition of grass imagery should adopt an integrative approach synthesizing the objectives of cultural translation with the intrinsic aesthetic characteristics of classical poetry.Through systematic analysis of the cultural semiotics embedded in grass symbolism,the research investigates practical translation techniques at lexical,syntactic,and stylistic dimensions.The findings aim to contribute to the theoretical framework of cultural image translation in Chinese poetic tradition while providing methodological references for cross-cultural interpretation of classical verse.By bridging cultural semiotics with translation praxis,this investigation seeks to advance the intercultural communication of Chinese poetic heritage through nuanced treatment of its botanical symbolism. 展开更多
关键词 classical Chinese poetry GRASS translation strategies cultural image
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Transformer-Based Fusion of Infrared and Visible Imagery for Smoke Recognition in Commercial Areas
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作者 Chongyang Wang Qiongyan Li +2 位作者 Shu Liu Pengle Cheng Ying Huang 《Computers, Materials & Continua》 2025年第9期5157-5176,共20页
With rapid urbanization,fires pose significant challenges in urban governance.Traditional fire detection methods often struggle to detect smoke in complex urban scenes due to environmental interferences and variations... With rapid urbanization,fires pose significant challenges in urban governance.Traditional fire detection methods often struggle to detect smoke in complex urban scenes due to environmental interferences and variations in viewing angles.This study proposes a novel multimodal smoke detection method that fuses infrared and visible imagery using a transformer-based deep learning model.By capturing both thermal and visual cues,our approach significantly enhances the accuracy and robustness of smoke detection in business parks scenes.We first established a dual-view dataset comprising infrared and visible light videos,implemented an innovative image feature fusion strategy,and designed a deep learning model based on the transformer architecture and attention mechanism for smoke classification.Experimental results demonstrate that our method outperforms existing methods,under the condition of multi-view input,it achieves an accuracy rate of 90.88%,precision rate of 98.38%,recall rate of 92.41%and false positive and false negative rates both below 5%,underlining the effectiveness of the proposed multimodal and multi-view fusion approach.The attention mechanism plays a crucial role in improving detection performance,particularly in identifying subtle smoke features. 展开更多
关键词 Multimodal image processing smoke recognition urban safety environmental monitoring
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Hyperspectral imagery quality assessment and band reconstruction using the prophet model
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作者 Ping Ma Jinchang Ren +2 位作者 Zhi Gao Yinhe Li Rongjun Chen 《CAAI Transactions on Intelligence Technology》 2025年第1期47-61,共15页
In Hyperspectral Imaging(HSI),the detrimental influence of noise and distortions on data quality is profound,which has severely affected the following-on analytics and decisionmaking such as land mapping.This study pr... In Hyperspectral Imaging(HSI),the detrimental influence of noise and distortions on data quality is profound,which has severely affected the following-on analytics and decisionmaking such as land mapping.This study presents an innovative framework for assessing HSI band quality and reconstructing the low-quality bands,based on the Prophet model.By introducing a comprehensive quality metric to start,the authors approach factors in both spatial and spectral characteristics across local and global scales.This metric effectively captures the intricate noise and distortions inherent in the HSI data.Subsequently,the authors employ the Prophet model to forecast information within the low-quality bands,leveraging insights from neighbouring high-quality bands.To validate the effectiveness of the authors’proposed model,extensive experiments on three publicly available uncorrected datasets are conducted.In a head-to-head comparison,the framework against six state-ofthe-art band reconstruction algorithms including three spectral methods,two spatialspectral methods and one deep learning method is benchmarked.The authors’experiments also delve into strategies for band selection based on quality metrics and the quality evaluation of the reconstructed bands.In addition,the authors assess the classification accuracy utilising these reconstructed bands.In various experiments,the results consistently affirm the efficacy of the authors’method in HSI quality assessment and band reconstruction.Notably,the authors’approach obviates the need for manually prefiltering of noisy bands.This comprehensive framework holds promise in addressing HSI data quality concerns whilst enhancing the overall utility of HSI. 展开更多
关键词 band reconstruction band quality hyperspectral image(HSI) prophet model
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Comparative Analysis of Deep Learning Models for Banana Plant Detection in UAV RGB and Grayscale Imagery
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作者 Ching-Lung Fan Yu-Jen Chung Shan-Min Yen 《Computers, Materials & Continua》 2025年第9期4627-4653,共27页
Efficient banana crop detection is crucial for precision agriculture;however,traditional remote sensing methods often lack the spatial resolution required for accurate identification.This study utilizes low-altitude U... Efficient banana crop detection is crucial for precision agriculture;however,traditional remote sensing methods often lack the spatial resolution required for accurate identification.This study utilizes low-altitude Unmanned Aerial Vehicle(UAV)images and deep learning-based object detection models to enhance banana plant detection.A comparative analysis of Faster Region-Based Convolutional Neural Network(Faster R-CNN),You Only Look Once Version 3(YOLOv3),Retina Network(RetinaNet),and Single Shot MultiBox Detector(SSD)was conducted to evaluate their effectiveness.Results show that RetinaNet achieved the highest detection accuracy,with a precision of 96.67%,a recall of 71.67%,and an F1 score of 81.33%.The study further highlights the impact of scale variation,occlusion,and vegetation density on detection performance.Unlike previous studies,this research systematically evaluates multi-scale object detection models for banana plant identification,offering insights into the advantages of UAV-based deep learning applications in agriculture.In addition,this study compares five evaluation metrics across the four detection models using both RGB and grayscale images.Specifically,RetinaNet exhibited the best overall performance with grayscale images,achieving the highest values across all five metrics.Compared to its performance with RGB images,these results represent a marked improvement,confirming the potential of grayscale preprocessing to enhance detection capability. 展开更多
关键词 Unmanned Aerial Vehicle image object detection deep learning banana crops
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Attention Driven YOLOv5 Network for Enhanced Landslide Detection Using Satellite Imagery of Complex Terrain
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作者 Naveen Chandra Himadri Vaidya +2 位作者 Suraj Sawant Shilpa Gite Biswajeet Pradhan 《Computer Modeling in Engineering & Sciences》 2025年第6期3351-3375,共25页
Landslide hazard detection is a prevalent problem in remote sensing studies,particularly with the technological advancement of computer vision.With the continuous and exceptional growth of the computational environmen... Landslide hazard detection is a prevalent problem in remote sensing studies,particularly with the technological advancement of computer vision.With the continuous and exceptional growth of the computational environment,the manual and partially automated procedure of landslide detection from remotely sensed images has shifted toward automatic methods with deep learning.Furthermore,attention models,driven by human visual procedures,have become vital in natural hazard-related studies.Hence,this paper proposes an enhanced YOLOv5(You Only Look Once version 5)network for improved satellite-based landslide detection,embedded with two popular attention modules:CBAM(Convolutional Block Attention Module)and ECA(Efficient Channel Attention).These attention mechanisms are incorporated into the backbone and neck of the YOLOv5 architecture,distinctly,and evaluated across three YOLOv5 variants:nano(n),small(s),and medium(m).The experiments use opensource satellite images from three distinct regions with complex terrain.The standard metrics,including F-score,precision,recall,and mean average precision(mAP),are computed for quantitative assessment.The YOLOv5n+CBAM demonstrates the most optimal results with an F-score of 77.2%,confirming its effectiveness.The suggested attention-driven architecture augments detection accuracy,supporting post-landslide event assessment and recovery. 展开更多
关键词 Attention mechanism convolutional neural networks LANDSLIDES remote sensing images YOLOv5
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人工智能在小肠息肉图像无创检测领域的研究进展 被引量:1
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作者 张新峰 高子君 +1 位作者 刘晓民 李相生 《北京工业大学学报》 北大核心 2026年第2期148-157,共10页
小肠息肉起病隐匿,临床症状特异性不强,检出有一定难度,内窥镜检查技术是最常用的小肠疾病检查技术,但此技术操作复杂,亦有一定的观察盲区,如盲肠后方、肠瓣膜后方。通过计算机断层扫描(computed tomography,CT)、核磁共振(magnetic res... 小肠息肉起病隐匿,临床症状特异性不强,检出有一定难度,内窥镜检查技术是最常用的小肠疾病检查技术,但此技术操作复杂,亦有一定的观察盲区,如盲肠后方、肠瓣膜后方。通过计算机断层扫描(computed tomography,CT)、核磁共振(magnetic resonance imaging,MRI)等无盲区的非侵入式检测方式进行病变定位识别,具有重要临床意义,利用人工智能技术有望提高小肠息肉诊断的敏感性、准确性和快捷性。鉴于此,分析了人工智能技术在小肠息肉无创检测中的最新研究进展,内容包括:图像分割、小肠息肉三维重建、小肠息肉疾病分类预测。旨在助力提升小肠息肉检测和诊断的准确率;明晰技术发展脉络,为后续研究提供方向。 展开更多
关键词 小肠息肉 医学图像处理 深度学习 图像分割 三维重建
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扩散加权成像评估慢性肾脏病患者左心室功能早期改变的初步研究
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作者 王欣全 陈嘉瑶 +4 位作者 葛勇钱 曹亮 李敏达 袁莉 顾红梅 《临床放射学杂志》 北大核心 2026年第1期66-71,共6页
目的观察磁共振扩散加权成像(DWI)评价慢性肾脏病(CKD)患者左心室功能早期改变的临床价值。方法对40名健康志愿者和70例CKD患者[CKD轻度损伤组(2~3期)37例,CKD重度损伤组(4~5期)33例]行心脏电影序列、DWI序列、T_(1) mapping及T_(2) map... 目的观察磁共振扩散加权成像(DWI)评价慢性肾脏病(CKD)患者左心室功能早期改变的临床价值。方法对40名健康志愿者和70例CKD患者[CKD轻度损伤组(2~3期)37例,CKD重度损伤组(4~5期)33例]行心脏电影序列、DWI序列、T_(1) mapping及T_(2) mapping检查,分别测量左心室质量指数(LVMI)、左心室射血分数(LVEF)、左心室收缩末期容积指数(LVESVI)、左心室舒张末期容积指数(LVEDVI)及ADC值、T_(1)值、T_(2)值,分析对照组与不同CKD组间各参数的差异,并探讨eGFR与心脏各参数的相关性。结果3组间LVMI、LVESVI、LVEDVI及ADC值、T_(1)值、T_(2)值差异均有统计学意义(P<0.001),且随CKD分期升高,LVMI、LVESVI、LVEDVI及ADC值、T_(1)值、T_(2)值均升高;LVEF在3组间差异无统计学意义(P>0.05),但随CKD分期升高,LVEF呈降低趋势。eGFR与ADC值、LVMI、LVESVI、LVEDVI及T_(1)值、T_(2)值均呈负相关(r=-0.696、-0.655、-0.688、-0.653、-0.770、-0.794,P<0.001),ADC鉴别CKD轻度损伤组与对照组ROC曲线下面积为0.924,鉴别CKD重度损伤组与对照组ROC曲线下面积为0.995。结论DWI在评价CKD患者左心室功能早期改变具有重要价值。 展开更多
关键词 扩散加权成像 磁共振成像 心室功能 慢性肾脏病
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基于条件生成对抗网络和混合注意力机制的图像隐写方法
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作者 李名 王孟齐 +2 位作者 张爱丽 任花 窦育强 《计算机应用》 北大核心 2026年第2期475-484,共10页
目前以图藏图的深度隐写术存在隐写图像安全性不强以及恢复的秘密图像中存在图像失真的问题,难以实际应用于隐私保护和秘密通信。针对以上问题,提出一种基于条件生成对抗网络和混合注意力机制的以图藏图隐写方法(CBAM-CGAN)。首先,在生... 目前以图藏图的深度隐写术存在隐写图像安全性不强以及恢复的秘密图像中存在图像失真的问题,难以实际应用于隐私保护和秘密通信。针对以上问题,提出一种基于条件生成对抗网络和混合注意力机制的以图藏图隐写方法(CBAM-CGAN)。首先,在生成器网络中引入混合注意模块,帮助生成器从通道和空间维度全面地学习图像特征,提高隐写图像的视觉质量;其次,引入残差连接降低网络学习过程中秘密图像的特征损失,并通过提取器和判别器的对抗训练,实现秘密图像的无噪声提取;最后,通过生成器和隐写分析器的对抗训练,提高隐写图像的安全性。在COCO等公开数据集上的实验结果显示,与StegGAN隐写方法相比,所提隐写方法的隐写图像和解密图像的峰值信噪比(PSNR)分别提高了4.37 dB和4.71 dB,结构相似性(SSIM)分别提高了9.16%和6.46%。在安全性方面,所提方法面对隐写分析器Ye-Net的检测,检测准确率(Acc)降低了9.35个百分点,误检率(FNR)提升了12.01个百分点。可见,所提方法在保证隐写图像安全性的同时能高质量地恢复秘密图像。 展开更多
关键词 深度学习 图像隐写 条件对抗生成网络 混合注意力机制 以图藏图
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单脉冲成像技术发展现状综述
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作者 王勇 刘禹锋 《雷达学报(中英文)》 北大核心 2026年第1期307-330,共24页
随着任务需求的日益多样化,雷达成像由传统的侧视和斜视模式开始向前视方向进行拓展。单脉冲成像技术凭借其前视成像能力、实时处理能力以及良好的抗干扰性能,能够有效克服传统成像方法在前视区域方位向分辨率低和多普勒对称模糊等问题... 随着任务需求的日益多样化,雷达成像由传统的侧视和斜视模式开始向前视方向进行拓展。单脉冲成像技术凭借其前视成像能力、实时处理能力以及良好的抗干扰性能,能够有效克服传统成像方法在前视区域方位向分辨率低和多普勒对称模糊等问题,成为解决该问题的一项关键技术。首先,该文介绍了单脉冲跟踪与单脉冲成像的区别,系统梳理了单脉冲成像的现有技术方法和评价指标,并对不同方法的性能进行了分析。接着,介绍了单脉冲成像技术在三维成像、运动目标定位成像以及多视角图像融合等不同场景中的具体应用案例。最后,展望了单脉冲成像技术的发展趋势,分析了成像质量提升和应用范围扩展等未来研究方向。 展开更多
关键词 单脉冲雷达 单脉冲成像 成像方法 三维成像 前视成像
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基于张量环多模低秩与图正则的遥感图像融合方法
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作者 马飞 曲强 +1 位作者 杨飞霞 徐光宪 《红外技术》 北大核心 2026年第2期166-175,共10页
遥感图像融合是一种获取高空间分辨率的高光谱图像非常经济且有效的途径,能够克服单一传感器的局限性,然而这是一个不适定的逆问题,且容易受到噪声污染。为了解决以上问题,本文提出了一种基于张量环分解的图像融合模型,将融合过程转化... 遥感图像融合是一种获取高空间分辨率的高光谱图像非常经济且有效的途径,能够克服单一传感器的局限性,然而这是一个不适定的逆问题,且容易受到噪声污染。为了解决以上问题,本文提出了一种基于张量环分解的图像融合模型,将融合过程转化为目标图像张量环因子的估计,利用低维子空间特征实现高维数据的超分辨率重构。首先,通过构建多模图正则项,挖掘张量环因子的局部相似性特征;其次,引入张量核范数对张量环因子进行截断式奇异值分解,逼近低维子空间全局低秩特征;最后设计了一种高效算法来实现模型优化求解。多组数据实验结果表明,本文提出的融合模型有效地提升了高光谱图像的空间分辨率,同时显著抑制了噪声。 展开更多
关键词 高光谱图像 张量环 遥感图像融合 张量分解 凸优化
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基于多尺度特征增强的航拍小目标检测算法 被引量:1
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作者 肖剑 何昕泽 +2 位作者 程鸿亮 杨小苑 胡欣 《浙江大学学报(工学版)》 北大核心 2026年第1期19-31,共13页
针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强... 针对航拍图像小目标检测中存在的检测精度低和模型参数量大的问题,提出兼顾性能与资源消耗的航拍小目标检测算法.以YOLOv8s为基准网络,通过降低通道维数和加强对高频特征的关注,提出自适应细节增强模块(ADEM),在减少冗余信息的同时加强对小目标细粒度特征的捕获;基于PAN-FPN架构调整特征融合网络,增加对浅层特征的关注,同时引入多尺度卷积核增强对目标上下文信息的关注,以适应小目标检测场景;针对传统IoU灵活性、泛化性不强的问题,构建参数可调的Nin-IoU,通过引入可调参数,实现对IoU的针对性调整,以适应不同检测任务的需求;提出轻量化检测头,在增强多尺度特征信息交融的同时减少冗余信息的传递.结果表明,在VisDrone2019数据集上,所提算法以8.08×106的参数量实现了mAP0.5=50.3%的检测精度;相较于基准算法YOLOv8s,参数量降低了27.4%,精度提升了11.5个百分点.在DOTA与DIOR数据集上的实验结果表明,所提算法具有较强的泛化能力. 展开更多
关键词 目标检测 YOLOv8 无人机图像 特征融合 损失函数
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语义引导的红外与可见光图像混合交叉特征融合方法
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作者 季赛 乔礼维 孙亚杰 《计算机科学》 北大核心 2026年第2期253-263,共11页
对于自编码器图像融合算法难以突出红外显著目标,现有融合策略难以同时考虑全局结构与局部细节信息,以及大多数融合算法过度关注统计指标,而忽视了高级视觉任务的支持需求的问题,提出了一种基于语义分割网络引导的图像融合方法,并设计... 对于自编码器图像融合算法难以突出红外显著目标,现有融合策略难以同时考虑全局结构与局部细节信息,以及大多数融合算法过度关注统计指标,而忽视了高级视觉任务的支持需求的问题,提出了一种基于语义分割网络引导的图像融合方法,并设计了混合交叉特征机制作为融合策略。首先,在编码器和解码器之间引入浅层和深层的跳跃连接,通过最大值选择策略融合特征,以突出显著目标并减少冗余信息。其次,融合策略采用混合交叉特征机制,在单一框架内通过交叉注意力和卷积操作融合不同模态特征,来整合全局上下文与局部细粒度信息。最后,将生成的融合图像输入到分割网络中,利用语义损失引导高级语义信息回流至融合网络,以生成具有丰富语义信息的融合图像。结果表明,所提方法在RoadScene数据集的SD,MI,VIFF,Qabf和AG等客观评价指标上,相较于7种对比算法分别平均提高了33.93%,112.81%,49.89%,27.64%,23.87%。在MSRS数据集的语义分割任务中,该方法在car,person和bicycle这3个类别上交并比超越了7种先进算法,分别平均提高了3.47%,6.37%和9.57%。 展开更多
关键词 图像融合 红外与可见光图像 交叉注意力机制 卷积 语义分割
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基于CASI高光谱数据的作物叶面积指数估算 被引量:10
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作者 唐建民 廖钦洪 +3 位作者 刘奕清 杨贵军 冯海宽 王纪华 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2015年第5期1351-1356,共6页
叶面积指数(LAI)的快速估算对于及时了解作物长势、病虫害监测以及产量评估具有重要意义。利用2012年7月7日在黑河流域张掖市获取的CASI高光谱数据,精确提取出了不同作物的光谱反射率,同时结合地面实测数据,对比分析了宽波段和"红... 叶面积指数(LAI)的快速估算对于及时了解作物长势、病虫害监测以及产量评估具有重要意义。利用2012年7月7日在黑河流域张掖市获取的CASI高光谱数据,精确提取出了不同作物的光谱反射率,同时结合地面实测数据,对比分析了宽波段和"红边"植被指数在估算作物LAI方面的潜力,在此基础上,基于波段组合算法,筛选出作物LAI估算的敏感波段,并构建了两个新型光谱指数NDSI和RSI,最后对研究区域作物LAI的空间分布进行了分析。结果表明,在植被覆盖度较低的情况下,宽波段植被指数NDVI对LAI具有较好的估算效果,模型的精度R2与RMSE分别为0.52,0.45(p<0.01);对于"红边"植被指数,由于CIred edge充分考虑了不同的作物类型,其对LAI的估算精度与NDVI一致;利用波段组合算法构建的光谱指数NDSI(569.00,654.80)和RSI(597.6,654.80)对LAI估算的效果要优于NDVI与CIred edge,其中,NDSI(569.00,654.80)主要利用了植被光谱"绿峰"和"红谷"附近的波段,模型估算的精度R2可达0.77(p<0.000 1);根据LAI与NDSI(569.00,654.80)之间的函数关系,绘制作物LAI的空间分布图,经分析,研究区域的西北部LAI值偏低,需增施肥料。研究结果,可为农业管理部门及时掌握作物长势信息、制定施肥策略提供技术支持。 展开更多
关键词 casi高光谱数据 叶面积指数 植被指数 波段组合 空间分布
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