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GPR Image Enhancement and Object Detection-Based Identification for Roadbed Subsurface Defect
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作者 Zhuangqiang Wen Min Zhang Zhekun Shou 《Structural Durability & Health Monitoring》 2026年第1期196-215,共20页
Roadbed disease detection is essential for maintaining road functionality.Ground penetrating radar(GPR)enables non-destructive detection without drilling.However,current identification often relies on manual inspectio... Roadbed disease detection is essential for maintaining road functionality.Ground penetrating radar(GPR)enables non-destructive detection without drilling.However,current identification often relies on manual inspection,which requires extensive experience,suffers from low efficiency,and is highly subjective.As the results are presented as radar images,image processing methods can be applied for fast and objective identification.Deep learning-based approaches now offer a robust solution for automated roadbed disease detection.This study proposes an enhanced Faster Region-based Convolutional Neural Networks(R-CNN)framework integrating ResNet-50 as the backbone and two-dimensional discrete Fourier spectrum transformation(2D-DFT)for frequency-domain feature fusion.A dedicated GPR image dataset comprising 1650 annotated images was constructed and augmented to 6600 images via median filtering,histogram equalization,and binarization.The proposed model segments defect regions,applies binary masking,and fuses frequency-domain features to improve small-target detection under noisy backgrounds.Experimental results show that the improved Faster R-CNN achieves a mean Average Precision(mAP)of 0.92,representing a 0.22 increase over the baseline.Precision improved by 26%while recall remained stable at 87%.The model was further validated on real urban road data,demonstrating robust detection capability even under interference.These findings highlight the potential of combining GPR with deep learning for efficient,non-destructive roadbed health monitoring. 展开更多
关键词 Roadbed diseases ground-penetrating radar Faster R-CNN image enhancement feature fusion
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Speech Emotion Recognition Based on the Adaptive Acoustic Enhancement and Refined Attention Mechanism
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作者 Jun Li Chunyan Liang +1 位作者 Zhiguo Liu Fengpei Ge 《Computers, Materials & Continua》 2026年第3期2015-2039,共25页
To enhance speech emotion recognition capability,this study constructs a speech emotion recognition model integrating the adaptive acoustic mixup(AAM)and improved coordinate and shuffle attention(ICASA)methods.The AAM... To enhance speech emotion recognition capability,this study constructs a speech emotion recognition model integrating the adaptive acoustic mixup(AAM)and improved coordinate and shuffle attention(ICASA)methods.The AAM method optimizes data augmentation by combining a sample selection strategy and dynamic interpolation coefficients,thus enabling information fusion of speech data with different emotions at the acoustic level.The ICASA method enhances feature extraction capability through dynamic fusion of the improved coordinate attention(ICA)and shuffle attention(SA)techniques.The ICA technique reduces computational overhead by employing depth-separable convolution and an h-swish activation function and captures long-range dependencies of multi-scale time-frequency features using the attention weights.The SA technique promotes feature interaction through channel shuffling,which helps the model learn richer and more discriminative emotional features.Experimental results demonstrate that,compared to the baseline model,the proposed model improves the weighted accuracy by 5.42%and 4.54%,and the unweighted accuracy by 3.37%and 3.85%on the IEMOCAP and RAVDESS datasets,respectively.These improvements were confirmed to be statistically significant by independent samples t-tests,further supporting the practical reliability and applicability of the proposed model in real-world emotion-aware speech systems. 展开更多
关键词 Speech emotion recognition adaptive acoustic mixup enhancement improved coordinate attention shuffle attention attention mechanism deep learning
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RetinexWT: Retinex-Based Low-Light Enhancement Method Combining Wavelet Transform
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作者 Hongji Chen Jianxun Zhang +2 位作者 Tianze Yu Yingzhu Zeng Huan Zeng 《Computers, Materials & Continua》 2026年第2期2113-2132,共20页
Low-light image enhancement aims to improve the visibility of severely degraded images captured under insufficient illumination,alleviating the adverse effects of illumination degradation on image quality.Traditional ... Low-light image enhancement aims to improve the visibility of severely degraded images captured under insufficient illumination,alleviating the adverse effects of illumination degradation on image quality.Traditional Retinex-based approaches,inspired by human visual perception of brightness and color,decompose an image into illumination and reflectance components to restore fine details.However,their limited capacity for handling noise and complex lighting conditions often leads to distortions and artifacts in the enhanced results,particularly under extreme low-light scenarios.Although deep learning methods built upon Retinex theory have recently advanced the field,most still suffer frominsufficient interpretability and sub-optimal enhancement performance.This paper presents RetinexWT,a novel framework that tightly integrates classical Retinex theory with modern deep learning.Following Retinex principles,RetinexWT employs wavelet transforms to estimate illumination maps for brightness adjustment.A detail-recovery module that synergistically combines Vision Transformer(ViT)and wavelet transforms is then introduced to guide the restoration of lost details,thereby improving overall image quality.Within the framework,wavelet decomposition splits input features into high-frequency and low-frequency components,enabling scale-specific processing of global illumination/color cues and fine textures.Furthermore,a gating mechanism selectively fuses down-sampled and up-sampled features,while an attention-based fusion strategy enhances model interpretability.Extensive experiments on the LOL dataset demonstrate that RetinexWT surpasses existing Retinex-oriented deeplearning methods,achieving an average Peak Signal-to-Noise Ratio(PSNR)improvement of 0.22 dB over the current StateOfTheArt(SOTA),thereby confirming its superiority in low-light image enhancement.Code is available at https://github.com/CHEN-hJ516/RetinexWT(accessed on 14 October 2025). 展开更多
关键词 Low-light image enhancement retinex algorithm wavelet transform vision transformer
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FENet:Underwater Image Enhancement via Frequency Domain Enhancement and Edge-Guided Refinement
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作者 Xinwei Zhu Jianxun Zhang Huan Zeng 《Computers, Materials & Continua》 2026年第2期1942-1966,共25页
Underwater images often affect the effectiveness of underwater visual tasks due to problems such as light scattering,color distortion,and detail blurring,limiting their application performance.Existing underwater imag... Underwater images often affect the effectiveness of underwater visual tasks due to problems such as light scattering,color distortion,and detail blurring,limiting their application performance.Existing underwater image enhancement methods,although they can improve the image quality to some extent,often lead to problems such as detail loss and edge blurring.To address these problems,we propose FENet,an efficient underwater image enhancement method.FENet first obtains three different scales of images by image downsampling and then transforms them into the frequency domain to extract the low-frequency and high-frequency spectra,respectively.Then,a distance mask and a mean mask are constructed based on the distance and magnitude mean for enhancing the high-frequency part,thus improving the image details and enhancing the effect by suppressing the noise in the low-frequency part.Affected by the light scattering of underwater images and the fact that some details are lost if they are directly reduced to the spatial domain after the frequency domain operation.For this reason,we propose a multi-stage residual feature aggregation module,which focuses on detail extraction and effectively avoids information loss caused by global enhancement.Finally,we combine the edge guidance strategy to further enhance the edge details of the image.Experimental results indicate that FENet outperforms current state-of-the-art underwater image enhancement methods in quantitative and qualitative evaluations on multiple publicly available datasets. 展开更多
关键词 Detail extraction frequency domain operation edge guidance image enhancement
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Effects of Input Enhancement on Chinese EFL Learners’Discourse Competence and Writing Performance in Comparative Continuation Writing
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作者 Xinyi Zhai Yinyin Du Qi Xu 《Chinese Journal of Applied Linguistics》 2026年第1期92-111,160,共21页
This study integrates explicit input enhancement into comparative continuation writing,defined as a task in which learners produce a continuation by comparing their own expression with an input text,aligning with its ... This study integrates explicit input enhancement into comparative continuation writing,defined as a task in which learners produce a continuation by comparing their own expression with an input text,aligning with its discourse structure and linguistic features,while developing their own ideas.It aims to examine whether English as a Foreign Language(EFL)learners in China exhibit differences in discourse competence and writing performance when completing comparative continuation writing combined with different input enhancement techniques,and whether the alignment effect occurs at the discourse level.Sixty first-year Chinese senior middle school students were divided into four groups:three groups engaged in comparative continuation writing with varying input enhancement,achieved by combining different techniques,while a control group performed a designated-topic writing task.The results revealed that three comparative continuation writing groups outperformed the designated-topic writing group in discourse competence,particularly in the use of temporal connectives.However,differences and some inconsistencies were observed among the comparative continuation writing groups across individual indices.The study highlights effective ways to incorporate comparative continuation writing into English instruction and demonstrates how explicit input enhancement can complement the task,simultaneously activating the alignment effect proposed by the xu-argument and enhancing discourse competence in writing. 展开更多
关键词 comparative continuation writing input enhancement discourse competence EFL writing performance
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M2ATNet: Multi-Scale Multi-Attention Denoising and Feature Fusion Transformer for Low-Light Image Enhancement
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作者 Zhongliang Wei Jianlong An Chang Su 《Computers, Materials & Continua》 2026年第1期1819-1838,共20页
Images taken in dim environments frequently exhibit issues like insufficient brightness,noise,color shifts,and loss of detail.These problems pose significant challenges to dark image enhancement tasks.Current approach... Images taken in dim environments frequently exhibit issues like insufficient brightness,noise,color shifts,and loss of detail.These problems pose significant challenges to dark image enhancement tasks.Current approaches,while effective in global illumination modeling,often struggle to simultaneously suppress noise and preserve structural details,especially under heterogeneous lighting.Furthermore,misalignment between luminance and color channels introduces additional challenges to accurate enhancement.In response to the aforementioned difficulties,we introduce a single-stage framework,M2ATNet,using the multi-scale multi-attention and Transformer architecture.First,to address the problems of texture blurring and residual noise,we design a multi-scale multi-attention denoising module(MMAD),which is applied separately to the luminance and color channels to enhance the structural and texture modeling capabilities.Secondly,to solve the non-alignment problem of the luminance and color channels,we introduce the multi-channel feature fusion Transformer(CFFT)module,which effectively recovers the dark details and corrects the color shifts through cross-channel alignment and deep feature interaction.To guide the model to learn more stably and efficiently,we also fuse multiple types of loss functions to form a hybrid loss term.We extensively evaluate the proposed method on various standard datasets,including LOL-v1,LOL-v2,DICM,LIME,and NPE.Evaluation in terms of numerical metrics and visual quality demonstrate that M2ATNet consistently outperforms existing advanced approaches.Ablation studies further confirm the critical roles played by the MMAD and CFFT modules to detail preservation and visual fidelity under challenging illumination-deficient environments. 展开更多
关键词 Low-light image enhancement multi-scale multi-attention TRANSFORMER
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UGEA-LMD: A Continuous-Time Dynamic Graph Representation Enhancement Framework for Lateral Movement Detection
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作者 Jizhao Liu Yuanyuan Shao +2 位作者 Shuqin Zhang Fangfang Shan Jun Li 《Computers, Materials & Continua》 2026年第1期1924-1943,共20页
Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address thes... Lateral movement represents the most covert and critical phase of Advanced Persistent Threats(APTs),and its detection still faces two primary challenges:sample scarcity and“cold start”of new entities.To address these challenges,we propose an Uncertainty-Driven Graph Embedding-Enhanced Lateral Movement Detection framework(UGEA-LMD).First,the framework employs event-level incremental encoding on a continuous-time graph to capture fine-grained behavioral evolution,enabling newly appearing nodes to retain temporal contextual awareness even in the absence of historical interactions and thereby fundamentally mitigating the cold-start problem.Second,in the embedding space,we model the dependency structure among feature dimensions using a Gaussian copula to quantify the uncertainty distribution,and generate augmented samples with consistent structural and semantic properties through adaptive sampling,thus expanding the representation space of sparse samples and enhancing the model’s generalization under sparse sample conditions.Unlike static graph methods that cannot model temporal dependencies or data augmentation techniques that depend on predefined structures,UGEA-LMD offers both superior temporaldynamic modeling and structural generalization.Experimental results on the large-scale LANL log dataset demonstrate that,under the transductive setting,UGEA-LMD achieves an AUC of 0.9254;even when 10%of nodes or edges are withheld during training,UGEA-LMD significantly outperforms baseline methods on metrics such as recall and AUC,confirming its robustness and generalization capability in sparse-sample and cold-start scenarios. 展开更多
关键词 Advanced persistent threat(APTs) lateral movement detection continuous-time dynamic graph data enhancement
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AquaTree:Deep Reinforcement Learning-Driven Monte Carlo Tree Search for Underwater Image Enhancement
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作者 Chao Li Jianing Wang +1 位作者 Caichang Ding Zhiwei Ye 《Computers, Materials & Continua》 2026年第3期1444-1464,共21页
Underwater images frequently suffer from chromatic distortion,blurred details,and low contrast,posing significant challenges for enhancement.This paper introduces AquaTree,a novel underwater image enhancement(UIE)meth... Underwater images frequently suffer from chromatic distortion,blurred details,and low contrast,posing significant challenges for enhancement.This paper introduces AquaTree,a novel underwater image enhancement(UIE)method that reformulates the task as a Markov Decision Process(MDP)through the integration of Monte Carlo Tree Search(MCTS)and deep reinforcement learning(DRL).The framework employs an action space of 25 enhancement operators,strategically grouped for basic attribute adjustment,color component balance,correction,and deblurring.Exploration within MCTS is guided by a dual-branch convolutional network,enabling intelligent sequential operator selection.Our core contributions include:(1)a multimodal state representation combining CIELab color histograms with deep perceptual features,(2)a dual-objective reward mechanism optimizing chromatic fidelity and perceptual consistency,and(3)an alternating training strategy co-optimizing enhancement sequences and network parameters.We further propose two inference schemes:an MCTS-based approach prioritizing accuracy at higher computational cost,and an efficient network policy enabling real-time processing with minimal quality loss.Comprehensive evaluations on the UIEB Dataset and Color correction and haze removal comparisons on the U45 Dataset demonstrate AquaTree’s superiority,significantly outperforming nine state-of-the-art methods across five established underwater image quality metrics. 展开更多
关键词 Underwater image enhancement(UIE) Monte Carlo tree search(MCTS) deep reinforcement learning(DRL) Markov decision process(MDP)
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Stability enhancement of MnO_(x)-CeO_(2)via hydrophobic modification for NO reduction by NH_(3)
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作者 Boyu Wu Shengen Zhang +2 位作者 Shengyang Zhang Bo Liu Bolin Zhang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期357-368,共12页
MnO_(x)-CeO_(2)catalysts for the low-temperature selective catalytic reduction(SCR)of NO remain vulnerable to water and sulfur poisoning,limting their practical applications.Herein,we report a hydrophobic-modified MnO... MnO_(x)-CeO_(2)catalysts for the low-temperature selective catalytic reduction(SCR)of NO remain vulnerable to water and sulfur poisoning,limting their practical applications.Herein,we report a hydrophobic-modified MnO_(x)-CeO_(2)catalyst that achieves enhanced NO conversion rate and stability under harsh conditions.The catalyst was synthesized by decorating MnOx crystals with amorphous CeO_(2),followed by loading hydrophobic silica on the external surfaces.The hydrophobic silica allowed the adsorption of NH_(3)and NO and diffusion of H,suppressed the adsorption of H_(2)O,and prevented SO_(2)interaction with the Mn active sites,achieving selective molecular discrimination at the catalyst surface.At 120℃,under H_(2)O and SO_(2)exposure,the optimal hydrophobic catalyst maintains 82%NO conversion rate compared with 69%for the unmodified catalyst.The average adsorption energies of NH_(3),H_(2)O,and SO_(2)decreased by 0.05,0.43,and 0.52 eV,respectively.The NO reduction pathway follows the Eley-Rideal mechanism,NH_(3)^(*)+*→NH_(2)^(*)+H^(*)followed by NH_(2)^(*)+NO^(*)→N_(2)^(*)+H_(2)O^(*),with NH_(3)dehydrogenation being the rate determining step.Hydrophobic modification increased the activation energy for H atom transfer,leading to a minor decrease in the NO conversion rate at 120℃.This work demonstrates a viable strategy for developing robust NH_(3)-S CR catalysts capable of efficient operation in water-and sulfur-rich environments. 展开更多
关键词 Mn-Ce catalyst NH_(3)-SCR hydrophobic modification enhanced stability
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Low-light image enhancement for UAVs guided by a light weighted map 被引量:1
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作者 BAI Xiaotong WANG Dianwei +2 位作者 FANG Jie LI Yuanqing XU Zhijie 《Optoelectronics Letters》 2025年第6期348-353,共6页
The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV imag... The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV images,which is inspired by the Retinex theory and guided by a light weighted map.Firstly,we propose a new network for reflectance component processing to suppress the noise in images.Secondly,we construct an illumination enhancement module that uses a light weighted map to guide the enhancement process.Finally,the processed reflectance and illumination components are recombined to obtain the enhancement results.Experimental results show that our method can suppress the noise in images while enhancing image brightness,and prevent over enhancement in bright regions.Code and data are available at https://gitee.com/baixiaotong2/uav-images.git. 展开更多
关键词 unmanned aerial vehicle retinex theory light weighted map reflectance component processing illumination enhancement module noise suppression unmanned aerial vehicle uav images low light image enhancement
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Raising microwave power drives solid effect DNP enhancements beyond 500 at 9.4 T
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作者 Hong Shi Qingjia Bao +2 位作者 Xin Zhou Maili Liu Chaoyang Liu 《Magnetic Resonance Letters》 2025年第2期79-80,共2页
Recently,an article was published on solid effect(SE)dynamic nuclear polarization(DNP)enhancement,where the au-thors reported achieving 1H enhancement factors up to 500 by increasing the microwave power at 9.4 T,marki... Recently,an article was published on solid effect(SE)dynamic nuclear polarization(DNP)enhancement,where the au-thors reported achieving 1H enhancement factors up to 500 by increasing the microwave power at 9.4 T,marking the highest SE enhancement to date[1]. 展开更多
关键词 se enhancement solid effect increasing microwave power dynamic nuclear polarization enhancement t microwave power
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LACC-RCE:A Local Adaptive Color Correction and Rayleigh-Based Contrast Enhancement Method for Underwater Image Enhancement
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作者 Tiancheng Liu 《Journal of Electronic Research and Application》 2025年第2期140-149,共10页
Underwater images are inherently degraded by color distortion,contrast reduction,and uneven brightness,primarily due to light absorption and scattering in water.To mitigate these challenges,a novel enhancement approac... Underwater images are inherently degraded by color distortion,contrast reduction,and uneven brightness,primarily due to light absorption and scattering in water.To mitigate these challenges,a novel enhancement approach is proposed,integrating Local Adaptive Color Correction(LACC)with contrast enhancement based on adaptive Rayleigh distribution stretching and CLAHE(LACC-RCE).Conventional color correction methods predominantly employ global adjustment strategies,which are often inadequate for handling spatially varying color distortions.In contrast,the proposed LACC method incorporates local color analysis,tone-weighted control,and spatially adaptive adjustments,allowing for region-specific color correction.This approach effectively enhances color fidelity and perceptual naturalness,addressing the limitations of global correction techniques.For contrast enhancement,the proposed method leverages the global mapping characteristics of the Rayleigh distribution to improve overall contrast,while CLAHE is employed to adaptively enhance local regions.A weighted fusion strategy is then applied to synthesize high-quality underwater images.Experimental results indicate that LACC-RCE surpasses conventional methods in color restoration,contrast optimization,and detail preservation,thereby enhancing the visual quality of underwater images.This improvement facilitates more reliable inputs for underwater object detection and recognition tasks. 展开更多
关键词 UNDERWATER Image enhancement Local adaptive color correction Rayleigh distribution stretching Contrast enhancement
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A symmetric difference data enhancement physics-informed neural network for the solving of discrete nonlinear lattice equations
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作者 Jian-Chen Zhou Xiao-Yong Wen Ming-Juan Guo 《Communications in Theoretical Physics》 2025年第6期21-29,共9页
In this paper,we propose a symmetric difference data enhancement physics-informed neural network(SDE-PINN)to study soliton solutions for discrete nonlinear lattice equations(NLEs).By considering known and unknown symm... In this paper,we propose a symmetric difference data enhancement physics-informed neural network(SDE-PINN)to study soliton solutions for discrete nonlinear lattice equations(NLEs).By considering known and unknown symmetric points,numerical simulations are conducted to one-soliton and two-soliton solutions of a discrete KdV equation,as well as a one-soliton solution of a discrete Toda lattice equation.Compared with the existing discrete deep learning approach,the numerical results reveal that within the specified spatiotemporal domain,the prediction accuracy by SDE-PINN is excellent regardless of the interior or extrapolation prediction,with a significant reduction in training time.The proposed data enhancement technique and symmetric structure development provides a new perspective for the deep learning approach to solve discrete NLEs.The newly proposed SDE-PINN can also be applied to solve continuous nonlinear equations and other discrete NLEs numerically. 展开更多
关键词 symmetric difference data enhancement physics-informed neural network data enhancement symmetric point soliton solutions discrete nonlinear lattice equations
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HIET:Hybrid Information Enhancement Transformer Network for Single-Photon Image Reconstruction
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作者 Yiming Liu Xuri Yao +2 位作者 Tao Zhang Yifei Sun Ying Fu 《Journal of Beijing Institute of Technology》 2025年第1期1-17,共17页
Single-photon sensors are novel devices with extremely high single-photon sensitivity and temporal resolution.However,these advantages also make them highly susceptible to noise.Moreover,single-photon cameras face sev... Single-photon sensors are novel devices with extremely high single-photon sensitivity and temporal resolution.However,these advantages also make them highly susceptible to noise.Moreover,single-photon cameras face severe quantization as low as 1 bit/frame.These factors make it a daunting task to recover high-quality scene information from noisy single-photon data.Most current image reconstruction methods for single-photon data are mathematical approaches,which limits information utilization and algorithm performance.In this work,we propose a hybrid information enhancement model which can significantly enhance the efficiency of information utilization by leveraging attention mechanisms from both spatial and channel branches.Furthermore,we introduce a structural feature enhance module for the FFN of the transformer,which explicitly improves the model's ability to extract and enhance high-frequency structural information through two symmetric convolution branches.Additionally,we propose a single-photon data simulation pipeline based on RAW images to address the challenge of the lack of single-photon datasets.Experimental results show that the proposed method outperforms state-of-the-art methods in various noise levels and exhibits a more efficient capability for recovering high-frequency structures and extracting information. 展开更多
关键词 single-photon images hybrid information enhancement structual feature enhancement data simulation pipeline
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A Low Light Image Enhancement Method Based on Dehazing Physical Model 被引量:1
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作者 Wencheng Wang Baoxin Yin +2 位作者 Lei Li Lun Li Hongtao Liu 《Computer Modeling in Engineering & Sciences》 2025年第5期1595-1616,共22页
In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,th... In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,this study presents a novel low-light image enhancement algorithm that leverages virtual hazy image generation through dehazing models based on statistical analysis.The proposed algorithm initiates the enhancement process by transforming the low-light image into a virtual hazy image,followed by image segmentation using a quadtree method.To improve the accuracy and robustness of atmospheric light estimation,the algorithm incorporates a genetic algorithm to optimize the quadtree-based estimation of atmospheric light regions.Additionally,this method employs an adaptive window adjustment mechanism to derive the dark channel prior image,which is subsequently refined using morphological operations and guided filtering.The final enhanced image is reconstructed through the hazy image degradation model.Extensive experimental evaluations across multiple datasets verify the superiority of the designed framework,achieving a peak signal-to-noise ratio(PSNR)of 17.09 and a structural similarity index(SSIM)of 0.74.These results indicate that the proposed algorithm not only effectively enhances image contrast and brightness but also outperforms traditional methods in terms of subjective and objective evaluation metrics. 展开更多
关键词 Dark channel prior quadtree decomposition genetic algorithm atmospheric light image enhancement
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An improved neighbourhood-based contrast limited adaptive histogram equalization method for contrast enhancement on retinal images 被引量:1
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作者 Arjuna Arulraj Jeya Sutha Mariadhason Reena Rose Ronjalis 《International Journal of Ophthalmology(English edition)》 2025年第12期2225-2236,共12页
AIM:To find the effective contrast enhancement method on retinal images for effective segmentation of retinal features.METHODS:A novel image preprocessing method that used neighbourhood-based improved contrast limited... AIM:To find the effective contrast enhancement method on retinal images for effective segmentation of retinal features.METHODS:A novel image preprocessing method that used neighbourhood-based improved contrast limited adaptive histogram equalization(NICLAHE)to improve retinal image contrast was suggested to aid in the accurate identification of retinal disorders and improve the visibility of fine retinal structures.Additionally,a minimal-order filter was applied to effectively denoise the images without compromising important retinal structures.The novel NICLAHE algorithm was inspired by the classical CLAHE algorithm,but enhanced it by selecting the clip limits and tile sized in a dynamical manner relative to the pixel values in an image as opposed to using fixed values.It was evaluated on the Drive and high-resolution fundus(HRF)datasets on conventional quality measures.RESULTS:The new proposed preprocessing technique was applied to two retinal image databases,Drive and HRF,with four quality metrics being,root mean square error(RMSE),peak signal to noise ratio(PSNR),root mean square contrast(RMSC),and overall contrast.The technique performed superiorly on both the data sets as compared to the traditional enhancement methods.In order to assess the compatibility of the method with automated diagnosis,a deep learning framework named ResNet was applied in the segmentation of retinal blood vessels.Sensitivity,specificity,precision and accuracy were used to analyse the performance.NICLAHE–enhanced images outperformed the traditional techniques on both the datasets with improved accuracy.CONCLUSION:NICLAHE provides better results than traditional methods with less error and improved contrastrelated values.These enhanced images are subsequently measured by sensitivity,specificity,precision,and accuracy,which yield a better result in both datasets. 展开更多
关键词 contrast limited adaptive histogram equalization retinal imaging image preprocessing contrast enhancement
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A Transformer Network Combing CBAM for Low-Light Image Enhancement 被引量:1
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作者 Zhefeng Sun Chen Wang 《Computers, Materials & Continua》 2025年第3期5205-5220,共16页
Recently,a multitude of techniques that fuse deep learning with Retinex theory have been utilized in the field of low-light image enhancement,yielding remarkable outcomes.Due to the intricate nature of imaging scenari... Recently,a multitude of techniques that fuse deep learning with Retinex theory have been utilized in the field of low-light image enhancement,yielding remarkable outcomes.Due to the intricate nature of imaging scenarios,including fluctuating noise levels and unpredictable environmental elements,these techniques do not fully resolve these challenges.We introduce an innovative strategy that builds upon Retinex theory and integrates a novel deep network architecture,merging the Convolutional Block Attention Module(CBAM)with the Transformer.Our model is capable of detecting more prominent features across both channel and spatial domains.We have conducted extensive experiments across several datasets,namely LOLv1,LOLv2-real,and LOLv2-sync.The results show that our approach surpasses other methods when evaluated against critical metrics such as Peak Signal-to-Noise Ratio(PSNR)and Structural Similarity Index(SSIM).Moreover,we have visually assessed images enhanced by various techniques and utilized visual metrics like LPIPS for comparison,and the experimental data clearly demonstrate that our approach excels visually over other methods as well. 展开更多
关键词 Low-light image enhancement CBAM TRANSFORMER
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Study of Prosody Enhancement of FastSpeech2 Speech Synthesis System Based on BERT
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作者 WEI Yi ZHAO Si-jia SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2025年第6期303-314,共12页
The traditional FastSpeech2 has high generation efficiency and speech naturalness,but it still has limitations in metrical modeling,especially in the lack of effective linkage between semantics and metre.To enhance th... The traditional FastSpeech2 has high generation efficiency and speech naturalness,but it still has limitations in metrical modeling,especially in the lack of effective linkage between semantics and metre.To enhance the performance of synthesized speech in terms of rhythmic expression,ProsodySpeech speech synthesis system that incorporates BERT pre-trained language model was proposed in this study.By introducing the Pre-trained Language Model Adapter(PLM Adapter)and the Semantic-Prosody Mapping Network(SPMN),and by fully utilizing the deep semantic information extracted by BERT,the system enhanced its control over rhythmic features such as pitch,energy,and duration.The proposed model achieved effective alignment and mapping between semantic information and prosody parameters by introducing a shared semantic processing layer,a global self-attention mechanism,and a specially designed prosody mapping branch.Experimental results showed that the model proposed in this study outperforms VITS and StyleTTS2 in terms of Mean Opinion Score(MOS),and the synthesized speech has a more obvious advantage in terms of rhythmic naturalness and expressive richness,which verified the effectiveness of the proposed model in enhancing the expression of speech rhythms,and the synthesized speech is closer to the expression of natural human speech. 展开更多
关键词 Speech synthesis BERT FastSpeech2 Prosody enhancement
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Low-Light Image Enhancement Model Based on Retinex Theory
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作者 SHANG Cheng SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 北大核心 2025年第5期14-20,57,共8页
Low-light image enhancement is one of the most active research areas in the field of computer vision in recent years.In the low-light image enhancement process,loss of image details and increase in noise occur inevita... Low-light image enhancement is one of the most active research areas in the field of computer vision in recent years.In the low-light image enhancement process,loss of image details and increase in noise occur inevitably,influencing the quality of enhanced images.To alleviate this problem,a low-light image enhancement model called RetinexNet model based on Retinex theory was proposed in this study.The model was composed of an image decomposition module and a brightness enhancement module.In the decomposition module,a convolutional block attention module(CBAM)was incorporated to enhance feature representation capacity of the network,focusing on crucial features and suppressing irrelevant ones.A multifeature fusion denoising module was designed within the brightness enhancement module,circumventing the issue of feature loss during downsampling.The proposed model outperforms the existing algorithms in terms of PSNR and SSIM metrics on the publicly available datasets LOL and MIT-Adobe FiveK,as well as gives superior results in terms of NIQE metrics on the publicly available dataset LIME. 展开更多
关键词 Low-light image enhancement Retinex model Noise suppression Feature fusion
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