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Hierarchical MPS-Based Three-Dimensional Geological Structure Reconstruction with Two-Dimensional Image(s) 被引量:3
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作者 Weisheng Hou Hengguang Liu +2 位作者 Tiancheng Zheng Wenjie Shen Fan Xiao 《Journal of Earth Science》 SCIE CAS CSCD 2021年第2期455-467,共13页
Multiple-point statistics(MPS)is a useful approach to reconstruct three-dimensional models in the macroscopic or microscopic field.Extracting spatial features for three-dimensional reconstruction from two-dimensional ... Multiple-point statistics(MPS)is a useful approach to reconstruct three-dimensional models in the macroscopic or microscopic field.Extracting spatial features for three-dimensional reconstruction from two-dimensional training images(TIs),and characterizing non-stationary features with directional ductility are two key issues in MPS simulation.This study presents a step-wise MPS-based three-dimensional structures reconstruction algorithm with the sequential process and hierarchical strategy based on two-dimensional images.An extension method is proposed to construct three-dimensional TIs.With a sequential simulation process,an initial guess at the coarsest scale is simulated,in which hierarchical strategy is used according to the characteristics of TIs.To obtain a more refined realization,an expectation-maximization like iterative process with global optimization is implemented.A concrete example of chondrite micro-structure simulation,in which one scanning electron microscopy(SEM)image of the Heyetang meteorite is used as TI,shows that the presented algorithm can simulate complex non-stationary structures. 展开更多
关键词 multiple-point statistics hierarchical strategy CHONDRITE two-dimensional image(s)
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An Analysis of Two-Dimensional Image Data Using a Grouping Estimator
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作者 Kazumitsu Nawata 《Open Journal of Statistics》 2022年第1期33-48,共16页
Machine learning methods, one type of methods used in artificial intelligence, are now widely used to analyze two-dimensional (2D) images in various fields. In these analyses, estimating the boundary between two regio... Machine learning methods, one type of methods used in artificial intelligence, are now widely used to analyze two-dimensional (2D) images in various fields. In these analyses, estimating the boundary between two regions is basic but important. If the model contains stochastic factors such as random observation errors, determining the boundary is not easy. When the probability distributions are mis-specified, ordinal methods such as probit and logit maximum likelihood estimators (MLE) have large biases. The grouping estimator is a semiparametric estimator based on the grouping of data that does not require specific probability distributions. For 2D images, the grouping is simple. Monte Carlo experiments show that the grouping estimator clearly improves the probit MLE in many cases. The grouping estimator essentially makes the resolution density lower, and the present findings imply that methods using low-resolution image analyses might not be the proper ones in high-density image analyses. It is necessary to combine and compare the results of high- and low-resolution image analyses. The grouping estimator may provide theoretical justifications for such analysis. 展开更多
关键词 two-dimensional image Analysis High-Resolution and Low-Resolution Im-ages Semiparametric Estimator Machine Learning Grouping Estimator
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Crack Length Quantification Based on Planar Eddy-Current Sensor Array and Two-Dimensional Image
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作者 Liu Lihui Tian Wugang +3 位作者 Pan Mengchun Chen Dixiang Xie Ruifang Ren Yuan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第6期1047-1052,共6页
Eddy-current (EC) testing is an effective electromagnetic non-destructive testing (NDT) technique.Planar eddy-current sensor arrays have several advantages such as good coherence,fast response speed,and high sensitivi... Eddy-current (EC) testing is an effective electromagnetic non-destructive testing (NDT) technique.Planar eddy-current sensor arrays have several advantages such as good coherence,fast response speed,and high sensitivity,which can be used for micro-damage inspection of crucial parts in mechanical equipments and aerospace aviation.The main purpose of this research is to detect the defect in a metallic material surface and identify the length of a crack using planar eddy-current sensor arrays in different directions.The principle and characteristics of planar eddy-current sensor arrays are introduced,and a crack length quantification algorithm in different directions is investigated.A damage quantitative detection system is established based on a field programmable gate array and ARM processor.The system is utilized to inspect the micro defect in a metallic material,which is carved to micro crack with size of 7mm(length)×0.1mm(width)×1mm(depth).The experimental data show that the sensor arrays can be used for the length measurement repeatedly,and that the uncertainty of the length measurement is below ±0.2mm. 展开更多
关键词 CRACK PLANAR EDDY-CURRENT sensor ARRAY NON-DESTRUCTIVE testing(NDT) quantification 2-D image
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Two-Dimensional Images of Current and Active Power Signals for Elevator Condition Recognition
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作者 Xunsheng Ji Dazhi Wang Kun Jiang 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第2期48-60,共13页
In this paper, an improved two-dimensional convolution neural network(2DCNN) is proposed to monitor and analyze elevator health, based on the distribution characteristics of elevator time series data in two-dimensiona... In this paper, an improved two-dimensional convolution neural network(2DCNN) is proposed to monitor and analyze elevator health, based on the distribution characteristics of elevator time series data in two-dimensional images. The current and effective power signals from an elevator traction machine are collected to generate gray-scale binary images. The improved two-dimensional convolution neural network is used to extract deep features from the images for classification, so as to recognize the elevator working conditions. Furthermore, the oscillation criterion is proposed to describe and analyze the active power oscillations. The current and active power are used to synchronously describe the working condition of the elevator, which can explain the co-occurrence state and potential relationship of elevator data. Based on the improved integration of local features of the time series, the recognition accuracy of the proposed 2DCNN is 97.78%, which is better than that of a one-dimensional convolution neural network. This research can improve the real-time monitoring and visual analysis performance of the elevator maintenance personnel, as well as improve their work efficiency. 展开更多
关键词 elevator condition CURRENT active power two-dimensional convolution network(2DCNN)
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Enhancing Post-Quantum Information Security: A Novel Two-Dimensional Chaotic System for Quantum Image Encryption
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作者 Fatima Asiri Wajdan Al Malwi 《Computer Modeling in Engineering & Sciences》 2025年第5期2053-2077,共25页
Ensuring information security in the quantum era is a growing challenge due to advancements in cryptographic attacks and the emergence of quantum computing.To address these concerns,this paper presents the mathematica... Ensuring information security in the quantum era is a growing challenge due to advancements in cryptographic attacks and the emergence of quantum computing.To address these concerns,this paper presents the mathematical and computer modeling of a novel two-dimensional(2D)chaotic system for secure key generation in quantum image encryption(QIE).The proposed map employs trigonometric perturbations in conjunction with rational-saturation functions and hence,named as Trigonometric-Rational-Saturation(TRS)map.Through rigorous mathematical analysis and computational simulations,the map is extensively evaluated for bifurcation behaviour,chaotic trajectories,and Lyapunov exponents.The security evaluation validates the map’s non-linearity,unpredictability,and sensitive dependence on initial conditions.In addition,the proposed TRS map has further been tested by integrating it in a QIE scheme.The QIE scheme first quantum-encodes the classic image using the Novel Enhanced Quantum Representation(NEQR)technique,the TRS map is used for the generation of secure diffusion key,which is XOR-ed with the quantum-ready image to obtain the encrypted images.The security evaluation of the QIE scheme demonstrates superior security of the encrypted images in terms of statistical security attacks and also against Differential attacks.The encrypted images exhibit zero correlation and maximum entropy with demonstrating strong resilience due to 99.62%and 33.47%results for Number of Pixels Change Rate(NPCR)and Unified Average Changing Intensity(UACI).The results validate the effectiveness of TRS-based quantum encryption scheme in securing digital images against emerging quantum threats,making it suitable for secure image encryption in IoT and edge-based applications. 展开更多
关键词 Information security chaotic map modeling post-quantum security quantum image encryption chaotic map image encryption
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Subpixel-based Bidirectional Distortion Correction for Two-dimensional Astronomical Fiber Spectral Images
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作者 Dong-Sheng Hu Chuan-Qi Chen +12 位作者 Hao-Jie Yang An-Zhi Wang Gang Yue Zhao-Xv Gan Xu-Dong Chen Yun-Xiang Yan Yue Zhong Zhi Xu Zhong-Quan Qu Peng-Fei Wang Tao Geng Shuang Chen Wei-Min Sun 《Research in Astronomy and Astrophysics》 2025年第3期45-56,共12页
This paper proposes a subpixel transformation method to correct Keystone and Smile distortions in fiber spectral images from the Fiber Arrayed Solar Optical Telescope.These distortions affect the spatial and spectral ... This paper proposes a subpixel transformation method to correct Keystone and Smile distortions in fiber spectral images from the Fiber Arrayed Solar Optical Telescope.These distortions affect the spatial and spectral positions,degrading resolution and accuracy.To correct Keystone distortion,we use a local summation and peak-finding method to locate central horizontal coordinates,calculate shifting values,and straighten the curves.For Smile distortion,we use quartic polynomial fitting based on absorption lines at different wavelengths.This technique preserves subpixel components,redistributes pixel values,and interpolates non-fiber portions,rectifying the spectra for accurate analysis.The method can also be applied to other astronomical projects like Large Sky Area Multi-Object Fiber Spectroscopic Telescope,enhancing the accuracy and reliability of spectral data in various astronomical studies. 展开更多
关键词 TECHNIQUES miscellaneous-techniques image processing-techniques spectroscopic-methods MISCELLANEOUS
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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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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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Two-dimensional grating line parameter calibration based on biaxial phase mapping
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作者 TENG Hai-rui LIANG Xu +3 位作者 JIN Si-yu SUN Yu-jia LI Wen-hao LIU Zhao-wu 《中国光学(中英文)》 北大核心 2026年第2期407-420,共14页
The two-dimensional grating serves as a critical component in plane grating interferometers for achieving high-precision multidimensional displacement measurements.The calibration of grating groove density and orthogo... The two-dimensional grating serves as a critical component in plane grating interferometers for achieving high-precision multidimensional displacement measurements.The calibration of grating groove density and orthogonality error of grating grooves not only improves the positioning accuracy of grating interferometers but also provides essential feedback for optimizing two-dimensional grating fabrication.This study proposes a method for simultaneous calibration of these parameters using orthogonal heterodyne laser interferometry.A two-dimensional grating interferometer is built with the grating to be measured,and a biaxial laser interferometer provides a displacement reference for it.The phase mapping relationship between grating interference and laser interference is established.The interference phase information obtained by any two displacements can simultaneously solve the above three parameters and obtain the grating installation error.The feasibility of the proposed method is verified by using a 1200 gr/mm two-dimensional grating.The standard deviation of the grating groove density in the X and Y directions is 0.012 gr/mm and 0.014 gr/mm,respectively.The standard deviation of the orthogonality error of grating grooves is 0.004°,and the standard deviation of the installation error is 0.002°.Compared with the atomic force microscope method,the consistency of the grating groove density in the X and Y directions is better than 0.03 gr/mm and 0.06 gr/mm,and the orthogonality error of grating grooves is better than 0.008°.The experimental results show that the proposed method can be simply and efficiently applied to the calibration of the grating line parameters of the two-dimensional grating. 展开更多
关键词 two-dimensional grating grating line parameter calibration grating groove density orthogonality error of grating grooves
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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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Two-Dimensional MXene-Based Advanced Sensors for Neuromorphic Computing Intelligent Application
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作者 Lin Lu Bo Sun +2 位作者 Zheng Wang Jialin Meng Tianyu Wang 《Nano-Micro Letters》 2026年第2期664-691,共28页
As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and el... As emerging two-dimensional(2D)materials,carbides and nitrides(MXenes)could be solid solutions or organized structures made up of multi-atomic layers.With remarkable and adjustable electrical,optical,mechanical,and electrochemical characteristics,MXenes have shown great potential in brain-inspired neuromorphic computing electronics,including neuromorphic gas sensors,pressure sensors and photodetectors.This paper provides a forward-looking review of the research progress regarding MXenes in the neuromorphic sensing domain and discussed the critical challenges that need to be resolved.Key bottlenecks such as insufficient long-term stability under environmental exposure,high costs,scalability limitations in large-scale production,and mechanical mismatch in wearable integration hinder their practical deployment.Furthermore,unresolved issues like interfacial compatibility in heterostructures and energy inefficiency in neu-romorphic signal conversion demand urgent attention.The review offers insights into future research directions enhance the fundamental understanding of MXene properties and promote further integration into neuromorphic computing applications through the convergence with various emerging technologies. 展开更多
关键词 two-dimensional MXenes SENSOR Neuromorphic computing Multimodal intelligent system Wearable electronics
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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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Intra-hour PV Power Forecasting Technique Based on Total-sky Images
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作者 Songjie Zhang Zhekang Dong +5 位作者 Donglian Qi Minghao Wang Zhao Xu Yifeng Han Yunfeng Yan Zhenming Li 《CSEE Journal of Power and Energy Systems》 2026年第1期210-219,共10页
Clouds are one of the leading causes of sun shading,which reduces the direct horizontal irradiance and curtails the photovoltaic(PV)power.It is critical to estimate cloud cover to accurately predict PV generation with... Clouds are one of the leading causes of sun shading,which reduces the direct horizontal irradiance and curtails the photovoltaic(PV)power.It is critical to estimate cloud cover to accurately predict PV generation within a very short horizon(second/minute).To achieve the precise forecasting of cloud cover,an image preprocessing method based on total-sky images is proposed to remove the interference and address the image edge distortion issue.An optimal threshold estimation method is further designed to achieve higher cloud identification precision.Considering the cloud's meteorological properties,a random hypersurface model(RHM)based on the Gaussian mixture probability hypothesis density(GM-PHD)filter is applied to track the cloud.The GM-PHD can track the rotation and diffusion of clouds,which helps to estimate sun-cloud collision.Furthermore,a hybrid autoregressive integrated moving average(ARIMA)and backpropagation(BP)neural network-based model is applied for intra-hour PV power forecasting.The experiment results demonstrate that the proposed cloud-tracking-based PV power forecasting model can capture the ramp behavior of PV power,improving forecasting precision. 展开更多
关键词 Cloud tracking image processing intra-hour PV forecasting solar energy total-sky image
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Two-dimensional kagome semiconductor Sc_(6)S_(5)X_(6)(X=Cl,Br,I)with trilayer kagome lattice
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作者 Jin-Ling Yan Xing-Yu Wang +5 位作者 Gen-Ping Wu Hao Wang Ya-Jiao Ke Jiafu Wang Zhi-Hong Liu Jun-Hui Yuan 《Chinese Physics B》 2026年第2期519-528,共10页
Two-dimensional(2D)multilayer kagome materials hold significant research value for regulating kagome-related physical properties and exploring quantum effects.However,their development is hindered by the scarcity of a... Two-dimensional(2D)multilayer kagome materials hold significant research value for regulating kagome-related physical properties and exploring quantum effects.However,their development is hindered by the scarcity of available material systems,making the identification of novel 2D multilayer kagome candidates particularly important.In this work,three types of 2D materials with trilayer kagome lattices,namely Sc_(6)S_(5)X_(6)(X=Cl,Br,I),are predicted based on first-principles calculations.These 2D materials feature two kagome lattices composed of Sc atoms and one kagome lattice composed of S atoms.Stability analysis indicates that these materials can exist as free-standing 2D materials.Electronic structure calculations reveal that Sc_(6)S_(5)X_(6)are narrow-bandgap semiconductors(0.76–0.95 e V),with their band structures exhibiting flat bands contributed by Sc-based kagome lattices and Dirac band gaps resulting from symmetry breaking.The sulfur-based kagome lattice in the central layer contributes an independent flat band below the Fermi level.Additionally,Sc_(6)S_(5)X_(6)exhibit high carrier mobility,with hole and electron mobilities reaching up to 10^(3)cm^(2)·V^(-1)·s^(-1),indicating potential applications in low-dimensional electronic devices.This work provides an excellent example for the development of novel multilayer 2D kagome materials. 展开更多
关键词 multilayer kagome lattice two-dimensional materials carrier mobility first-principles calculations
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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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