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Synaptic pruning mechanisms and application of emerging imaging techniques in neurological disorders
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作者 Yakang Xing Yi Mo +1 位作者 Qihui Chen Xiao Li 《Neural Regeneration Research》 2026年第5期1698-1714,共17页
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience... Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders. 展开更多
关键词 CHEMOKINE COMPLEMENT experience-dependent driven synaptic pruning imaging techniques NEUROGLIA signaling pathways synapse elimination synaptic pruning
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Research on Multi-Level Automatic Filling Optimization Design Method for Layered Cross-Sectional Layout of Umbilical 被引量:1
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作者 YIN Xu FAN Zhi-rui +4 位作者 CAO Dong-hui LIU Yu-jie LI Meng-shu YAN Jun YANG Zhi-xun 《China Ocean Engineering》 2025年第5期891-903,共13页
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple... The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections. 展开更多
关键词 UMBILICAL cross-sectional layout multi-level filling layered layout optimization design
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:1
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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SFPBL:Soft Filter Pruning Based on Logistic Growth Differential Equation for Neural Network
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作者 Can Hu Shanqing Zhang +2 位作者 Kewei Tao Gaoming Yang Li Li 《Computers, Materials & Continua》 2025年第3期4913-4930,共18页
The surge of large-scale models in recent years has led to breakthroughs in numerous fields,but it has also introduced higher computational costs and more complex network architectures.These increasingly large and int... The surge of large-scale models in recent years has led to breakthroughs in numerous fields,but it has also introduced higher computational costs and more complex network architectures.These increasingly large and intricate networks pose challenges for deployment and execution while also exacerbating the issue of network over-parameterization.To address this issue,various network compression techniques have been developed,such as network pruning.A typical pruning algorithm follows a three-step pipeline involving training,pruning,and retraining.Existing methods often directly set the pruned filters to zero during retraining,significantly reducing the parameter space.However,this direct pruning strategy frequently results in irreversible information loss.In the early stages of training,a network still contains much uncertainty,and evaluating filter importance may not be sufficiently rigorous.To manage the pruning process effectively,this paper proposes a flexible neural network pruning algorithm based on the logistic growth differential equation,considering the characteristics of network training.Unlike other pruning algorithms that directly reduce filter weights,this algorithm introduces a three-stage adaptive weight decay strategy inspired by the logistic growth differential equation.It employs a gentle decay rate in the initial training stage,a rapid decay rate during the intermediate stage,and a slower decay rate in the network convergence stage.Additionally,the decay rate is adjusted adaptively based on the filter weights at each stage.By controlling the adaptive decay rate at each stage,the pruning of neural network filters can be effectively managed.In experiments conducted on the CIFAR-10 and ILSVRC-2012 datasets,the pruning of neural networks significantly reduces the floating-point operations while maintaining the same pruning rate.Specifically,when implementing a 30%pruning rate on the ResNet-110 network,the pruned neural network not only decreases floating-point operations by 40.8%but also enhances the classification accuracy by 0.49%compared to the original network. 展开更多
关键词 Filter pruning channel pruning CNN complexity deep neural networks filtering theory logistic model
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Hierarchical Shape Pruning for 3D Sparse Convolution Networks
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作者 Haiyan Long Chonghao Zhang +2 位作者 Xudong Qiu Hai Chen Gang Chen 《Computers, Materials & Continua》 2025年第8期2975-2988,共14页
3D sparse convolution has emerged as a pivotal technique for efficient voxel-based perception in autonomous systems,enabling selective feature extraction from non-empty voxels while suppressing computational waste.Des... 3D sparse convolution has emerged as a pivotal technique for efficient voxel-based perception in autonomous systems,enabling selective feature extraction from non-empty voxels while suppressing computational waste.Despite its theoretical efficiency advantages,practical implementations face under-explored limitations:the fixed geometric patterns of conventional sparse convolutional kernels inevitably process non-contributory positions during sliding-window operations,particularly in regions with uneven point cloud density.To address this,we propose Hierarchical Shape Pruning for 3D Sparse Convolution(HSP-S),which dynamically eliminates redundant kernel stripes through layer-adaptive thresholding.Unlike static soft pruning methods,HSP-S maintains trainable sparsity patterns by progressively adjusting pruning thresholds during optimization,enlarging original parameter search space while removing redundant operations.Extensive experiments validate effectiveness of HSP-S acrossmajor autonomous driving benchmarks.On KITTI’s 3D object detection task,our method reduces 93.47%redundant kernel computations whilemaintaining comparable accuracy(1.56%mAP drop).Remarkably,on themore complexNuScenes benchmark,HSP-S achieves simultaneous computation reduction(21.94%sparsity)and accuracy gains(1.02%mAP(mean Average Precision)and 0.47%NDS(nuScenes detection score)improvement),demonstrating its scalability to diverse perception scenarios.This work establishes the first learnable shape pruning framework that simultaneously enhances computational efficiency and preserves detection accuracy in 3D perception systems. 展开更多
关键词 Shape pruning model compressing 3D sparse convolution
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Computation graph pruning based on critical path retention in evolvable networks
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作者 XIE Xiaoyan YANG Tianjiao +4 位作者 ZHU Yun LUO Xing JIN Luochen YU Jinhao REN Xun 《High Technology Letters》 2025年第3期266-272,共7页
The dynamic routing mechanism in evolvable networks enables adaptive reconfiguration of topol-ogical structures and transmission pathways based on real-time task requirements and data character-istics.However,the heig... The dynamic routing mechanism in evolvable networks enables adaptive reconfiguration of topol-ogical structures and transmission pathways based on real-time task requirements and data character-istics.However,the heightened architectural complexity and expanded parameter dimensionality in evolvable networks present significant implementation challenges when deployed in resource-con-strained environments.Due to the critical paths ignored,traditional pruning strategies cannot get a desired trade-off between accuracy and efficiency.For this reason,a critical path retention pruning(CPRP)method is proposed.By deeply traversing the computational graph,the dependency rela-tionship among nodes is derived.Then the nodes are grouped and sorted according to their contribu-tion value.The redundant operations are removed as much as possible while ensuring that the criti-cal path is not affected.As a result,computational efficiency is improved while a higher accuracy is maintained.On the CIFAR benchmark,the experimental results demonstrate that CPRP-induced pruning incurs accuracy degradation below 4.00%,while outperforming traditional feature-agnostic grouping methods by an average 8.98%accuracy improvement.Simultaneously,the pruned model attains a 2.41 times inference acceleration while achieving 48.92%parameter compression and 53.40%floating-point operations(FLOPs)reduction. 展开更多
关键词 evolvable network computation graph traversing dynamic routing critical path retention pruning
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Optimizing BERT for Bengali Emotion Classification: Evaluating Knowledge Distillation, Pruning, and Quantization
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作者 Md Hasibur Rahman Mohammed Arif Uddin +1 位作者 Zinnat Fowzia Ria Rashedur M.Rahman 《Computer Modeling in Engineering & Sciences》 2025年第2期1637-1666,共30页
The rapid growth of digital data necessitates advanced natural language processing(NLP)models like BERT(Bidi-rectional Encoder Representations from Transformers),known for its superior performance in text classificati... The rapid growth of digital data necessitates advanced natural language processing(NLP)models like BERT(Bidi-rectional Encoder Representations from Transformers),known for its superior performance in text classification.However,BERT’s size and computational demands limit its practicality,especially in resource-constrained settings.This research compresses the BERT base model for Bengali emotion classification through knowledge distillation(KD),pruning,and quantization techniques.Despite Bengali being the sixth most spoken language globally,NLP research in this area is limited.Our approach addresses this gap by creating an efficient BERT-based model for Bengali text.We have explored 20 combinations for KD,quantization,and pruning,resulting in improved speedup,fewer parameters,and reduced memory size.Our best results demonstrate significant improvements in both speed and efficiency.For instance,in the case of mBERT,we achieved a 3.87×speedup and 4×compression ratio with a combination of Distil+Prune+Quant that reduced parameters from 178 to 46 M,while the memory size decreased from 711 to 178 MB.These results offer scalable solutions for NLP tasks in various languages and advance the field of model compression,making these models suitable for real-world applications in resource-limited environments. 展开更多
关键词 Bengali NLP black-box distillation emotion classification model compression post-training quantization unstructured pruning
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CLAD:Criterion learner and attention distillation for automated CNN pruning
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作者 Zheng Li Jiaxin Li +2 位作者 Shaojie Liu Bo Zhao Derong Liu 《Journal of Automation and Intelligence》 2025年第4期254-265,共12页
Filter pruning effectively compresses the neural network by reducing both its parameters and computational cost.Existing pruning methods typically rely on pre-designed pruning criteria to measure filter importance and... Filter pruning effectively compresses the neural network by reducing both its parameters and computational cost.Existing pruning methods typically rely on pre-designed pruning criteria to measure filter importance and remove those deemed unimportant.However,different layers of the neural network exhibit varying filter distributions,making it inappropriate to implement the same pruning criterion for all layers.Additionally,some approaches apply different criteria from the set of pre-defined pruning rules for different layers,but the limited space leads to the difficulty of covering all layers.If criteria for all layers are manually designed,it is costly and difficult to generalize to other networks.To solve this problem,we present a novel neural network pruning method based on the Criterion Learner and Attention Distillation(CLAD).Specifically,CLAD develops a differentiable criterion learner,which is integrated into each layer of the network.The learner can automatically learn the appropriate pruning criterion according to the filter parameters of each layer,thus the requirement of manual design is eliminated.Furthermore,the criterion learner is trained end-to-end by the gradient optimization algorithm to achieve efficient pruning.In addition,attention distillation,which fully utilizes the knowledge of unpruned networks to guide the optimization of the learner and improve the pruned network performance,is introduced in the process of learner optimization.Experiments conducted on various datasets and networks demonstrate the effectiveness of the proposed method.Notably,CLAD reduces the FLOPs of Res Net-110 by about 53%on the CIFAR-10 dataset,while simultaneously improves the network's accuracy by 0.05%.Moreover,it reduces the FLOPs of Res Net-50 by about 46%on the Image Net-1K dataset,and maintains a top-1 accuracy of 75.45%. 展开更多
关键词 Neural network pruning Model compression Knowledge distillation Feature attention Polar regularization
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Greedy Pruning Algorithm for DETR Architecture Networks Based on Global Optimization
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作者 HUANG Qiubo XU Jingsai +2 位作者 ZHANG Yakui WANG Mei CHEN Dehua 《Journal of Donghua University(English Edition)》 2025年第1期96-105,共10页
End-to-end object detection Transformer(DETR)successfully established the paradigm of the Transformer architecture in the field of object detection.Its end-to-end detection process and the idea of set prediction have ... End-to-end object detection Transformer(DETR)successfully established the paradigm of the Transformer architecture in the field of object detection.Its end-to-end detection process and the idea of set prediction have become one of the hottest network architectures in recent years.There has been an abundance of work improving upon DETR.However,DETR and its variants require a substantial amount of memory resources and computational costs,and the vast number of parameters in these networks is unfavorable for model deployment.To address this issue,a greedy pruning(GP)algorithm is proposed,applied to a variant denoising-DETR(DN-DETR),which can eliminate redundant parameters in the Transformer architecture of DN-DETR.Considering the different roles of the multi-head attention(MHA)module and the feed-forward network(FFN)module in the Transformer architecture,a modular greedy pruning(MGP)algorithm is proposed.This algorithm separates the two modules and applies their respective optimal strategies and parameters.The effectiveness of the proposed algorithm is validated on the COCO 2017 dataset.The model obtained through the MGP algorithm reduces the parameters by 49%and the number of floating point operations(FLOPs)by 44%compared to the Transformer architecture of DN-DETR.At the same time,the mean average precision(mAP)of the model increases from 44.1%to 45.3%. 展开更多
关键词 model pruning object detection Transformer(DETR) Transformer architecture object detection
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Multi-relation spatiotemporal graph residual network model with multi-level feature attention:A novel approach for landslide displacement prediction
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作者 Ziqian Wang Xiangwei Fang +3 位作者 Wengang Zhang Xuanming Ding Luqi Wang Chao Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4211-4226,共16页
Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,ther... Accurate prediction of landslide displacement is crucial for effective early warning of landslide disasters.While most existing prediction methods focus on time-series forecasting for individual monitoring points,there is limited research on the spatiotemporal characteristics of landslide deformation.This paper proposes a novel Multi-Relation Spatiotemporal Graph Residual Network with Multi-Level Feature Attention(MFA-MRSTGRN)that effectively improves the prediction performance of landslide displacement through spatiotemporal fusion.This model integrates internal seepage factors as data feature enhancements with external triggering factors,allowing for accurate capture of the complex spatiotemporal characteristics of landslide displacement and the construction of a multi-source heterogeneous dataset.The MFA-MRSTGRN model incorporates dynamic graph theory and four key modules:multilevel feature attention,temporal-residual decomposition,spatial multi-relational graph convolution,and spatiotemporal fusion prediction.This comprehensive approach enables the efficient analyses of multi-source heterogeneous datasets,facilitating adaptive exploration of the evolving multi-relational,multi-dimensional spatiotemporal complexities in landslides.When applying this model to predict the displacement of the Liangshuijing landslide,we demonstrate that the MFA-MRSTGRN model surpasses traditional models,such as random forest(RF),long short-term memory(LSTM),and spatial temporal graph convolutional networks(ST-GCN)models in terms of various evaluation metrics including mean absolute error(MAE=1.27 mm),root mean square error(RMSE=1.49 mm),mean absolute percentage error(MAPE=0.026),and R-squared(R^(2)=0.88).Furthermore,feature ablation experiments indicate that incorporating internal seepage factors improves the predictive performance of landslide displacement models.This research provides an advanced and reliable method for landslide displacement prediction. 展开更多
关键词 Landslide displacement prediction Spatiotemporal fusion Dynamic graph Data feature enhancement multi-level feature attention
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A robust method for large-scale route optimization on lunar surface utilizing a multi-level map model
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作者 Yutong JIA Shengnan ZHANG +5 位作者 Bin LIU Kaichang DI Bin XIE Jing NAN Chenxu ZHAO Gang WAN 《Chinese Journal of Aeronautics》 2025年第3期134-150,共17页
As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could ra... As we look ahead to future lunar exploration missions, such as crewed lunar exploration and establishing lunar scientific research stations, the lunar rovers will need to cover vast distances. These distances could range from kilometers to tens of kilometers, and even hundreds and thousands of kilometers. Therefore, it is crucial to develop effective long-range path planning for lunar rovers to meet the demands of lunar patrol exploration. This paper presents a hierarchical map model path planning method that utilizes the existing high-resolution images, digital elevation models and mineral abundance maps. The objective is to address the issue of the construction of lunar rover travel costs in the absence of large-scale, high-resolution digital elevation models. This method models the reference and semantic layers using the middle- and low-resolution remote sensing data. The multi-scale obstacles on the lunar surface are extracted by combining the deep learning algorithm on the high-resolution image, and the obstacle avoidance layer is modeled. A two-stage exploratory path planning decision is employed for long-distance driving path planning on a global–local scale. The proposed method analyzes the long-distance accessibility of various areas of scientific significance, such as Rima Bode. A high-precision digital elevation model is created using stereo images to validate the method. Based on the findings, it can be observed that the entire route spans a distance of 930.32 km. The route demonstrates an impressive ability to avoid meter-level impact craters and linear structures while maintaining an average slope of less than 8°. This paper explores scientific research by traversing at least seven basalt units, uncovering the secrets of lunar volcanic activities, and establishing ‘golden spike’ reference points for lunar stratigraphy. The final result of path planning can serve as a valuable reference for the design, mission demonstration, and subsequent project implementation of the new manned lunar rover. 展开更多
关键词 Crewed lunar exploration Long-range path planningi multi-level map Deep learning Volcanic activities
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Multi-level distribution alignment-based domain adaptation for segmentation of 3D neuronal soma images
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作者 Li Ma Xuantai Xu Xiaoquan Yang 《Journal of Innovative Optical Health Sciences》 2025年第6期69-85,共17页
Deep learning networks are increasingly exploited in the field of neuronal soma segmentation.However,annotating dataset is also an expensive and time-consuming task.Unsupervised domain adaptation is an effective metho... Deep learning networks are increasingly exploited in the field of neuronal soma segmentation.However,annotating dataset is also an expensive and time-consuming task.Unsupervised domain adaptation is an effective method to mitigate the problem,which is able to learn an adaptive segmentation model by transferring knowledge from a rich-labeled source domain.In this paper,we propose a multi-level distribution alignment-based unsupervised domain adaptation network(MDA-Net)for segmentation of 3D neuronal soma images.Distribution alignment is performed in both feature space and output space.In the feature space,features from different scales are adaptively fused to enhance the feature extraction capability for small target somata and con-strained to be domain invariant by adversarial adaptation strategy.In the output space,local discrepancy maps that can reveal the spatial structures of somata are constructed on the predicted segmentation results.Then thedistribution alignment is performed on the local discrepancies maps across domains to obtain a superior discrepancy map in the target domain,achieving refined segmentation performance of neuronal somata.Additionally,after a period of distribution align-ment procedure,a portion of target samples with high confident pseudo-labels are selected as training data,which assist in learning a more adaptive segmentation network.We verified the superiority of the proposed algorithm by comparing several domain adaptation networks on two 3D mouse brain neuronal somata datasets and one macaque brain neuronal soma dataset. 展开更多
关键词 Unsupervised domain adaptation multi-level distribution alignment pseudo-labels 3D neuronal soma images
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MLRT-UNet:An Efficient Multi-Level Relation Transformer Based U-Net for Thyroid Nodule Segmentation
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作者 Kaku Haribabu Prasath R Praveen Joe IR 《Computer Modeling in Engineering & Sciences》 2025年第4期413-448,共36页
Thyroid nodules,a common disorder in the endocrine system,require accurate segmentation in ultrasound images for effective diagnosis and treatment.However,achieving precise segmentation remains a challenge due to vari... Thyroid nodules,a common disorder in the endocrine system,require accurate segmentation in ultrasound images for effective diagnosis and treatment.However,achieving precise segmentation remains a challenge due to various factors,including scattering noise,low contrast,and limited resolution in ultrasound images.Although existing segmentation models have made progress,they still suffer from several limitations,such as high error rates,low generalizability,overfitting,limited feature learning capability,etc.To address these challenges,this paper proposes a Multi-level Relation Transformer-based U-Net(MLRT-UNet)to improve thyroid nodule segmentation.The MLRTUNet leverages a novel Relation Transformer,which processes images at multiple scales,overcoming the limitations of traditional encoding methods.This transformer integrates both local and global features effectively through selfattention and cross-attention units,capturing intricate relationships within the data.The approach also introduces a Co-operative Transformer Fusion(CTF)module to combine multi-scale features from different encoding layers,enhancing the model’s ability to capture complex patterns in the data.Furthermore,the Relation Transformer block enhances long-distance dependencies during the decoding process,improving segmentation accuracy.Experimental results showthat the MLRT-UNet achieves high segmentation accuracy,reaching 98.2% on the Digital Database Thyroid Image(DDT)dataset,97.8% on the Thyroid Nodule 3493(TG3K)dataset,and 98.2% on the Thyroid Nodule3K(TN3K)dataset.These findings demonstrate that the proposed method significantly enhances the accuracy of thyroid nodule segmentation,addressing the limitations of existing models. 展开更多
关键词 Thyroid nodules endocrine system multi-level relation transformer U-Net self-attention external attention co-operative transformer fusion thyroid nodules segmentation
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A Novel Reduced Error Pruning Tree Forest with Time-Based Missing Data Imputation(REPTF-TMDI)for Traffic Flow Prediction
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作者 Yunus Dogan Goksu Tuysuzoglu +4 位作者 Elife Ozturk Kiyak Bita Ghasemkhani Kokten Ulas Birant Semih Utku Derya Birant 《Computer Modeling in Engineering & Sciences》 2025年第8期1677-1715,共39页
Accurate traffic flow prediction(TFP)is vital for efficient and sustainable transportation management and the development of intelligent traffic systems.However,missing data in real-world traffic datasets poses a sign... Accurate traffic flow prediction(TFP)is vital for efficient and sustainable transportation management and the development of intelligent traffic systems.However,missing data in real-world traffic datasets poses a significant challenge to maintaining prediction precision.This study introduces REPTF-TMDI,a novel method that combines a Reduced Error Pruning Tree Forest(REPTree Forest)with a newly proposed Time-based Missing Data Imputation(TMDI)approach.The REP Tree Forest,an ensemble learning approach,is tailored for time-related traffic data to enhance predictive accuracy and support the evolution of sustainable urbanmobility solutions.Meanwhile,the TMDI approach exploits temporal patterns to estimate missing values reliably whenever empty fields are encountered.The proposed method was evaluated using hourly traffic flow data from a major U.S.roadway spanning 2012-2018,incorporating temporal features(e.g.,hour,day,month,year,weekday),holiday indicator,and weather conditions(temperature,rain,snow,and cloud coverage).Experimental results demonstrated that the REPTF-TMDI method outperformed conventional imputation techniques across various missing data ratios by achieving an average 11.76%improvement in terms of correlation coefficient(R).Furthermore,REPTree Forest achieved improvements of 68.62%in RMSE and 70.52%in MAE compared to existing state-of-the-art models.These findings highlight the method’s ability to significantly boost traffic flow prediction accuracy,even in the presence of missing data,thereby contributing to the broader objectives of sustainable urban transportation systems. 展开更多
关键词 Machine learning traffic flow prediction missing data imputation reduced error pruning tree(REPTree) sustainable transportation systems traffic management artificial intelligence
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立木攀爬修枝机器人设计与试验
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作者 周志标 蒙丽雯 +1 位作者 郑贤 蒙艳玫 《农机化研究》 北大核心 2026年第2期1-10,共10页
立木在生长过程中保留过多的分枝会导致树势早衰,同时树枝生长过大会在树干内形成死节,进而影响树木成材。为了对立木进行自动化修枝,使修枝人员远离危险的修枝环境,设计了一种可定点修枝的立木攀爬修枝机器人。首先,确定了攀爬机构采... 立木在生长过程中保留过多的分枝会导致树势早衰,同时树枝生长过大会在树干内形成死节,进而影响树木成材。为了对立木进行自动化修枝,使修枝人员远离危险的修枝环境,设计了一种可定点修枝的立木攀爬修枝机器人。首先,确定了攀爬机构采用直行攀爬、修枝机构采用旋转修枝的设计方案,并通过SolidWorks软件完成了整机的虚拟样机设计;其次,对关键部件的基本结构参数和工作参数进行了计算,完成了关键零部件的选型,并求解了修枝机构中滑台调节距离和环轨旋转角度的方程式;最后,完成物理样机的加工和装配,并搭建了试验平台,对机器人的攀爬性能和修枝性能进行了验证。结果表明:机器人能够克服摩擦阻力、机器人重力和加速阻力沿模拟树干稳定攀爬,最高攀爬速度约为1.18 m/s,打滑率约为6.11%;适合在直径80~230 mm的树干上进行攀爬和修枝作业;可修剪树枝的最大直径约为40 mm,修枝后切口平整度达75%以上,残留的枝茬长度约为5 mm,证明了机器人设计的功能性和可行性。 展开更多
关键词 立木 攀爬修枝机器人 定点修枝
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基于小规模异构语言模型一致性委员会的数据剪枝方法
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作者 王凯文 王蕴哲 +3 位作者 谈威 傅启明 陆悠 陈建平 《计算机应用研究》 北大核心 2026年第1期110-119,共10页
大型语言模型(LLMs)的微调效果高度依赖于训练数据的质量,但现有的基于单模型困惑度的数据评估方法存在困惑度偏差(低困惑度样本可能仍被错误预测)和跨模型分歧(不同模型对同一样本的困惑度不一致)的局限性。为此,该研究提出了一种基于... 大型语言模型(LLMs)的微调效果高度依赖于训练数据的质量,但现有的基于单模型困惑度的数据评估方法存在困惑度偏差(低困惑度样本可能仍被错误预测)和跨模型分歧(不同模型对同一样本的困惑度不一致)的局限性。为此,该研究提出了一种基于异构小语言模型委员会一致性的方法,从两个方面评估数据价值:一方面计算多模型对同一数据样本的困惑度的变异系数来量化模型间分歧;另一方面结合预测结果与基准答案的相似性来计算预测难度。综合这两方面的评估结果,提出MMCS(多模型一致性)指标,用于高质量训练数据筛选。实验结果表明,基于MMCS筛选的数据在两种主流LLM和三个公开数据集上的微调性能优于传统方法,在36次对比实验中有27次取得最优效果,为高效数据剪枝提供了新的思路,证实了基于多模型分歧的评估方法在提升数据边际效益方面的有效性。 展开更多
关键词 大语言模型 数据修剪 多模型委员会 困惑度
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复配益生元缓解便秘效果和途径探究
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作者 蔡华昊 刘运柱 +5 位作者 朱胜男 王榕 李乾乾 张莉 王琳琳 崔树茂 《食品工业科技》 北大核心 2026年第1期420-432,共13页
目的:便秘是一种常见的功能性胃肠疾病,需要可持续且无副作用的缓解手段。方法:本研究采用洛哌丁胺诱导小鼠便秘模型,评估了复配益生元对便秘的缓解作用。研究首先考察了复配益生元对便秘表观指标的影响,后续进一步对便秘相关胃肠调节... 目的:便秘是一种常见的功能性胃肠疾病,需要可持续且无副作用的缓解手段。方法:本研究采用洛哌丁胺诱导小鼠便秘模型,评估了复配益生元对便秘的缓解作用。研究首先考察了复配益生元对便秘表观指标的影响,后续进一步对便秘相关胃肠调节递质、肠道屏障系统、结肠组织损伤情况、粪便内短链脂肪酸含量和肠道菌群进行了检测。结果:复配益生元可以通过下调有害菌Bilophila、Anaerovorax的相对丰度,上调有益菌Ileibacterium、Bifidobacterium的相对丰度,从而上调结肠内兴奋性胃肠调节递质含量(胃泌素和P物质),改善肠道屏障系统(上调粘蛋白2、闭锁蛋白、干细胞因子表达量,下调水通道蛋白3 mRNA相对表达量),改善结肠组织损伤,上调粪便中乙酸、丁酸含量,最终下调排首粒黑便时间(相比模型组缩短了27%),增加粪便含水量(相比模型组增加了46%),有效缓解便秘。而复配益生元与西梅汁复配后可以进一步上调有益菌Odoribacter、Faecalibaculum、Defluviitaleaceae_UCG-011的相对丰度,进一步上调结肠内胃泌素、胃动素含量,下调结肠内降钙素基因相关肽含量,上调粘蛋白2 mRNA相对表达量,上调粪便中乙酸、丁酸含量,增加小肠推进率(相比模型组增加了47%)和5 h内排便量(相比模型组增加了132%),从而更有效地缓解便秘。结论:复配益生元(每100 mL中主要含有低聚木糖3 g、水苏糖3 g、低聚半乳糖8 g)可缓解便秘,益生元与西梅汁复配后可以通过增强小肠推进率和提高菌群调节能力进而更有效地缓解便秘。本研究发现了西梅汁可以增强益生元缓解便秘的功效,为多种类低剂量益生元配方的开发提供了数据支持,为后续开发新型便秘缓解策略提供了科学依据。 展开更多
关键词 便秘 益生元 西梅汁 胃肠调节递质 肠道机械屏障 肠道菌群
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蓝靛果修剪管理技术
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作者 张利军 黄宏 +3 位作者 霍俊伟 秦栋 郭良川 石德山 《防护林科技》 2026年第1期84-87,共4页
基于10余年蓝靛果(Lonicera caerulea)栽培管理实践与推广示范经验,以鲜食新品种“蓝精灵”为研究对象,紧扣其物候期特征及品种特异性,系统解析蓝靛果全生育期修剪技术。聚焦苗木定植、树势培育、盛果期调控到衰老期更新的完整生产周期... 基于10余年蓝靛果(Lonicera caerulea)栽培管理实践与推广示范经验,以鲜食新品种“蓝精灵”为研究对象,紧扣其物候期特征及品种特异性,系统解析蓝靛果全生育期修剪技术。聚焦苗木定植、树势培育、盛果期调控到衰老期更新的完整生产周期,提炼出各关键环节(包括幼树整形、结果枝组培养、负载量平衡和老弱树复壮等)的标准化修剪方案。成果以科普化语言阐释专业操作细节,为种植户、技术推广人员提供精准参考。 展开更多
关键词 蓝靛果 物候期 修剪
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Multi-level access control model for tree-like hierarchical organizations
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作者 於光灿 李瑞轩 +3 位作者 卢正鼎 Mudar Sarem 宋伟 苏永红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期393-396,共4页
An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning secur... An access control model is proposed based on the famous Bell-LaPadula (BLP) model.In the proposed model,hierarchical relationships among departments are built,a new concept named post is proposed,and assigning security tags to subjects and objects is greatly simplified.The interoperation among different departments is implemented through assigning multiple security tags to one post, and the more departments are closed on the organization tree,the more secret objects can be exchanged by the staff of the departments.The access control matrices of the department,post and staff are defined.By using the three access control matrices,a multi granularity and flexible discretionary access control policy is implemented.The outstanding merit of the BLP model is inherited,and the new model can guarantee that all the information flow is under control.Finally,our study shows that compared to the BLP model,the proposed model is more flexible. 展开更多
关键词 multi-level access control hierarchical organization multiple security tags
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基于剪枝的YOLOv8轻量化苹果表面缺陷检测算法
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作者 刘鹏扬 亚森江·木沙 《中国农机化学报》 北大核心 2026年第1期108-117,共10页
在苹果表面缺陷检测中,快速且高精度的检测技术至关重要。当前的研究在精度上取得进展,但推理速度仍然有待提升,为此,提出一种基于剪枝的轻量化苹果表面缺陷检测算法。采用YOLOv8n为基础模型,结合GhostNetV2与YOLOv8结构中C2f的特性,设... 在苹果表面缺陷检测中,快速且高精度的检测技术至关重要。当前的研究在精度上取得进展,但推理速度仍然有待提升,为此,提出一种基于剪枝的轻量化苹果表面缺陷检测算法。采用YOLOv8n为基础模型,结合GhostNetV2与YOLOv8结构中C2f的特性,设计一种C2f—GhostV2模块,显著减少模型参数量并加快推理速度。为进一步减小计算负荷,模型引入幽灵卷积(GhostConv)代替传统卷积,并采用动态上采样(DySample)机制提升灵活性与信息保留能力。此外,轻量化模型经过基于层自适应幅度的剪枝(LAMP),进一步减少浮点运算量。结果表明,剪枝后的模型平均精度均值达到97.3%,与原模型相比,浮点运算次数减少78.05%,推理速度提高27.85%。 展开更多
关键词 苹果 表面缺陷检测 轻量化 剪枝 小目标检测
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