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An effective deep-learning prediction of Arctic sea-ice concentration based on the U-Net model
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作者 Yifan Xie Ke Fan +2 位作者 Hongqing Yang Yi Fan Shengping He 《Atmospheric and Oceanic Science Letters》 2026年第1期34-40,共7页
Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiote... Current shipping,tourism,and resource development requirements call for more accurate predictions of the Arctic sea-ice concentration(SIC).However,due to the complex physical processes involved,predicting the spatiotemporal distribution of Arctic SIC is more challenging than predicting its total extent.In this study,spatiotemporal prediction models for monthly Arctic SIC at 1-to 3-month leads are developed based on U-Net-an effective convolutional deep-learning approach.Based on explicit Arctic sea-ice-atmosphere interactions,11 variables associated with Arctic sea-ice variations are selected as predictors,including observed Arctic SIC,atmospheric,oceanic,and heat flux variables at 1-to 3-month leads.The prediction skills for the monthly Arctic SIC of the test set(from January 2018 to December 2022)are evaluated by examining the mean absolute error(MAE)and binary accuracy(BA).Results showed that the U-Net model had lower MAE and higher BA for Arctic SIC compared to two dynamic climate prediction systems(CFSv2 and NorCPM).By analyzing the relative importance of each predictor,the prediction accuracy relies more on the SIC at the 1-month lead,but on the surface net solar radiation flux at 2-to 3-month leads.However,dynamic models show limited prediction skills for surface net solar radiation flux and other physical processes,especially in autumn.Therefore,the U-Net model can be used to capture the connections among these key physical processes associated with Arctic sea ice and thus offers a significant advantage in predicting Arctic SIC. 展开更多
关键词 Arctic sea-ice concentration Deep-learning prediction U-Net model CFSv2 NorCPM
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Enhancing Lightweight Mango Disease Detection Model Performance through a Combined Attention Module
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作者 Wen-Tsai Sung Indra Griha TofikIsa Sung-Jung Hsiao 《Computers, Materials & Continua》 2026年第2期986-1016,共31页
Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this... Mango is a plant with high economic value in the agricultural industry;thus,it is necessary to maximize the productivity performance of the mango plant,which can be done by implementing artificial intelligence.In this study,a lightweight object detection model will be developed that can detect mango plant conditions based on disease potential,so that it becomes an early detection warning system that has an impact on increasing agricultural productivity.The proposed lightweight model integrates YOLOv7-Tiny and the proposed modules,namely the C2S module.The C2S module consists of three sub-modules such as the convolutional block attention module(CBAM),the coordinate attention(CA)module,and the squeeze-and-excitation(SE)module.The dataset is constructed by eight classes,including seven classes of disease conditions and one class of health conditions.The experimental result shows that the proposed lightweight model has the optimal results,which increase by 13.15% of mAP50 compared to the original model YOLOv7-Tiny.While the mAP50:95 also achieved the highest results compared to other models,including YOLOv3-Tiny,YOLOv4-Tiny,YOLOv5,and YOLOv7-Tiny.The advantage of the proposed lightweightmodel is the adaptability that supports it in constrained environments,such as edge computing systems.This proposedmodel can support a robust,precise,and convenient precision agriculture system for the user. 展开更多
关键词 Mango lightweight model combined attention module C2S module precision agriculture
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Multi-source and multi-attribute collaborative fracture network modeling of a sandstone reservoir in Ordos Basin
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作者 Yinbang Zhou 《Energy Geoscience》 2026年第1期214-223,共10页
The effective channeling of fluid flow by fractures is a liability for enhanced oil recovery(EOR)methods like CO_(2) flooding or CO_(2) storage.Developing a distributed fracture model to understand the heterogeneity o... The effective channeling of fluid flow by fractures is a liability for enhanced oil recovery(EOR)methods like CO_(2) flooding or CO_(2) storage.Developing a distributed fracture model to understand the heterogeneity of the fracture network is essential in characterizing tight and low-permeability reservoirs.In the Ordos Basin,the Chang 8-1-2 layer of the Yanchang Formation is a typical tight and low permeability reservoir in the JH17 wellblock.The strong heterogeneity of distributed fractures,differing fracture scales and fracture types make it difficult to effectively characterize the fracture distribution within the Chang 8-1-2 layer.In this paper,multi-source and multi-attribute methods are used to integrate data into a neural network at different scales,and fuzzy logic control is used to judge the correlation of various attributes.The results suggest that attribute correlation between coherence and fracture indication is the best,followed by correlations with fault distance,north–south slope,and north–south curvature.Advantageous attributes from the target area are used to train the neural network,and the fracture density model and discrete fracture network(DFN)model are built at different scales.This method can be used to effectively predict the distribution characteristics of fractures in the study area.And any learning done by the neural network from this case study can be applied to fracture network modeling for reservoirs of the same type. 展开更多
关键词 Tight oil reservoir CO_(2)flooding CO_(2)storage Reservoir fracture Fracture network modeling Fracture density
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The Continuation Task and the Model-as-Feedback Writing Task in L2 Writing Development:Timing of Model Texts
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作者 Xiaoyan Zhang 《Chinese Journal of Applied Linguistics》 2026年第1期76-91,160,共17页
This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a con... This study compares the relative efficacy of the continuation task and the model-as-feedbackwriting (MAFW) task in EFL writing development. Ninety intermediate-level Chinese EFL learnerswere randomly assigned to a continuation group, a MAFW group, and a control group, each with30 learners. A pretest and a posttest were used to gauge L2 writing development. Results showedthat the continuation task outperformed the MAFW task not only in enhancing the overall qualityof L2 writing, but also in promoting the quality of three components of L2 writing, namely, content,organization, and language. The finding has important implications for L2 writing teaching andlearning. 展开更多
关键词 continuation task model-as-feedback writing task L2 writing development timing of model texts
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QingNangTCM:a parameter-efficient fine-tuning large language model for traditional Chinese medicine
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作者 Xuming Tong Liyan Liu +7 位作者 Yanhong Yuan Xiaozheng Ding Huiru Jia Xu Yang Sio Kei Im Mini Han Wang Zhang Xiong Yapeng Wang 《Digital Chinese Medicine》 2026年第1期1-12,共12页
Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific c... Objective To develop QingNangTCM,a specialized large language model(LLM)tailored for expert-level traditional Chinese medicine(TCM)question-answering and clinical reasoning,addressing the scarcity of domain-specific corpora and specialized alignment.Methods We constructed QnTCM_Dataset,a corpus of 100000 entries,by integrating data from ShenNong_TCM_Dataset and SymMap v2.0,and synthesizing additional samples via retrieval-augmented generation(RAG)and persona-driven generation.The dataset comprehensively covers diagnostic inquiries,prescriptions,and herbal knowledge.Utilizing P-Tuning v2,we fine-tuned the GLM-4-9B-Chat backbone to develop QingNangTCM.A multidimensional evaluation framework,assessing accuracy,coverage,consistency,safety,professionalism,and fluency,was established using metrics such as bilingual evaluation understudy(BLEU),recall-oriented understudy for gisting evaluation(ROUGE),metric for evaluation of translation with explicit ordering(METEOR),and LLM-as-a-Judge with expert review.Qualitative analysis was conducted across four simulated clinical scenarios:symptom analysis,disease treatment,herb inquiry,and failure cases.Baseline models included GLM-4-9BChat,DeepSeek-V2,HuatuoGPT-II(7B),and GLM-4-9B-Chat(freeze-tuning).Results QingNangTCM achieved the highest scores in BLEU-1/2/3/4(0.425/0.298/0.137/0.064),ROUGE-1/2(0.368/0.157),and METEOR(0.218),demonstrating a balanced and superior normalized performance profile of 0.900 across the dimensions of accuracy,coverage,and consistency.Although its ROUGE-L score(0.299)was lower than that of HuatuoGPT-II(7B)(0.351),it significantly outperformed domain-specific models in expert-validated win rates for professionalism(86%)and safety(73%).Qualitative analysis confirmed that the model strictly adheres to the“symptom-syndrome-pathogenesis-treatment”reasoning chain,though occasional misclassifications and hallucinations persisted when dealing with rare medicinal materials and uncommon syndromes. 展开更多
关键词 Large language model(LLM) Traditional Chinese medicine(TCM) Fine-tuning P-Tuning v2 Clinical decision support
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SAM2融合RGB-D坐标转换的工件几何参数测量
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作者 宋涛 王泓竣 +2 位作者 简圣前 汤斌 邹政 《仪器仪表学报》 北大核心 2025年第10期331-344,共14页
尺寸测量是工业产品外观质检的重要环节,传统接触式测量效率低、受主观因素影响大。而视觉测量需针对不同对象设计对应的尺寸边界提取方案,高精度三维测量更是开发难度大,适用性不足。针对以上问题,故提出一种基于零样本分割大模型(SAM2... 尺寸测量是工业产品外观质检的重要环节,传统接触式测量效率低、受主观因素影响大。而视觉测量需针对不同对象设计对应的尺寸边界提取方案,高精度三维测量更是开发难度大,适用性不足。针对以上问题,故提出一种基于零样本分割大模型(SAM2)融合RGB-D坐标转换的非接触式工件主体参数测量方法。首先,评估阈值分割、边缘分割、颜色空间分割、GrabCut分割这4类传统图像分割算法的掩膜分割效果,选取其中最优者GrabCut分割,与主流深度学习分割算法及SAM2进行对比,以证明SAM2的优越性;然后,搭建双目立体视觉实验平台,采集工件高精度点云,并对点云进行滤波、平滑、空洞填补等处理,然后采集目标工件深度图和RGB图,利用SAM2的零样本泛化分割能力,通过正负点交互引导,在RGB图上实现高精度目标分割,得到初始掩膜;接着采用形态学优化和连通域分析生成拓扑闭合的平滑掩膜,并通过主成分分析(PCA)提取其特征骨架;最后沿骨架生成垂线段并融合对齐的深度图三维坐标计算几何参数。通过对比数显游标卡尺和点云的测量结果,对所提方法测量结果进行分析。实验结果表明,在套筒、钳具和电机这3类工件测量中,套筒直径测量平均绝对误差为0.0175 mm,钳具与电机参数测量平均绝对误差分别为0.0283和0.0237 mm,均满足精度要求。 展开更多
关键词 工件几何参数测量 sam2 RGB-D图 非接触测量
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基于SAM2多任务学习的山区地块模糊边界提取 被引量:3
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作者 黄启厅 凌玉荣 +6 位作者 谢国雪 杨绍锷 杨颖频 李海亮 梁存穗 何新洁 谢意 《南方农业学报》 北大核心 2025年第1期18-28,F0002,共12页
【目的】构建多任务模糊边界提取深度学习模型,解决模糊边界难提取及伪边界难消除的问题,为地块破碎地区的地块边界提取提供参考依据。【方法】以广西河池市宜州区为研究区,通过解译典型山区破碎遥感影像,建立模糊边界提取数据集,引入S... 【目的】构建多任务模糊边界提取深度学习模型,解决模糊边界难提取及伪边界难消除的问题,为地块破碎地区的地块边界提取提供参考依据。【方法】以广西河池市宜州区为研究区,通过解译典型山区破碎遥感影像,建立模糊边界提取数据集,引入SAM2视觉大模型及采用适配器Adapter微调优化其编码器,设计地块属性提取辅助任务,构建多任务模糊边界提取深度学习模型SAM2Xi,并通过对比试验证实该模型在山区地块破碎环境下的模糊边界提取效果。【结果】SAM2Xi模型在全局最佳阈值(ODS)和单图最佳阈值(OIS)上表现最佳,分别为0.663和0.672,显示出最高的边缘检测精度和适应性,但50%精度召回率(R50)略低于DexiNed模型。SAM2Xi模型结合语义信息与边缘特征,增强了模糊边界识别能力,在复杂场景下表现尤为出色;SAM2Xi模型在低对比度和复杂背景下仍然保持高精度,模糊边界区域的细节保留、连贯性和噪声抑制均优于其他模型;此外,SAM2Xi模型在伪边界清除任务中表现最佳,其先进特征提取和优化机制几乎完全消除了伪边界干扰,在各类场景下保持高精度边缘检测,具有更高的鲁棒性和准确性。SAM2Xi模型能成功提取研究区的地块信息(地块图斑数1587597个,总面积145696.646 ha),且提取的地块分布与实际情况高度吻合,具体表现为:(1)在大片耕地范围内可准确划分各地块;(2)可提取建筑物中的零星耕地或园地;(3)可提取林地中能被单独分割的地块(人工林),但自然林基本不会被误识。【结论】基于SAM2多任务学习构建的SAM2Xi模型实现了模糊边界识别与伪边界清除的双重突破,在复杂地形适应性、边界连贯性保持及噪声抑制方面具有明显优势,为我国西南山区复杂地形下地块边界提取及山区农业资源精准管理提供了技术支撑。 展开更多
关键词 地块边界提取 sam2 多任务学习 遥感影像 sam2Xi模型
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基于24Model的动火作业事故致因文本挖掘 被引量:1
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作者 牛茂辉 李威君 +1 位作者 刘音 王璐 《中国安全科学学报》 北大核心 2025年第3期151-158,共8页
为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告... 为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告数据集,构建分类模型;然后,通过基于BERT的关键字提取算法(KeyBERT)和词频-逆文档频率(TF-IDF)算法的组合权重,结合24Model框架,建立动火作业事故文本关键词指标体系;最后,通过文本挖掘关键词之间的网络共现关系,分析得到事故致因之间的相互关联。结果显示,基于BERT的24Model分类器模型能够系统准确地判定动火作业事故致因类别,通过组合权重筛选得到4个层级关键词指标体系,其中安全管理体系的权重最大,结合共现网络分析得到动火作业事故的7项关键致因。 展开更多
关键词 “2-4”模型(24model) 动火作业 事故致因 文本挖掘 指标体系
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基于SAM2的矿井钻杆分割计数方法 被引量:1
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作者 刘宋波 姜媛媛 《佳木斯大学学报(自然科学版)》 2025年第11期29-32,共4页
针对传统钻杆计数方法受环境影响、精度低的问题,提出基于SAM2大模型的矿井钻杆分割方法。优化SAM2结构,引入YOLOv8作为提示模块提升目标定位能力,采用Shape-IoU与BCE Loss构建联合损失函数优化边界回归,并通过LoRA微调提升模型性能。... 针对传统钻杆计数方法受环境影响、精度低的问题,提出基于SAM2大模型的矿井钻杆分割方法。优化SAM2结构,引入YOLOv8作为提示模块提升目标定位能力,采用Shape-IoU与BCE Loss构建联合损失函数优化边界回归,并通过LoRA微调提升模型性能。实验结果表明,该方法在强光、弱光、遮挡等复杂场景下均表现优异,相较于原始SAM2模型,mAP提升2.6%,mIoU提升4.7%,钻杆计数准确率达98.4%,有效提升钻杆目标分割与计数精度,为煤矿瓦斯抽采提供技术支持。 展开更多
关键词 煤矿井下 sam2大模型 目标分割 钻杆计数
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基于SAM2分割大模型和K-Means聚类算法的岩屑图像识别方法
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作者 丁燕 崔淑英 +3 位作者 王舸 崔猛 刘雪峰 牛建伟 《石油钻采工艺》 北大核心 2025年第5期646-655,共10页
钻井过程中对上返岩屑的监测与识别是感知地层变化、及时发现掉块并减缓井壁失稳风险的关键手段。实现快速、客观、自动化的岩屑识别对保障钻井安全、提高钻井效率具有重要意义。目前,岩屑识别主要依赖人工经验判断,存在主观性强、耗时... 钻井过程中对上返岩屑的监测与识别是感知地层变化、及时发现掉块并减缓井壁失稳风险的关键手段。实现快速、客观、自动化的岩屑识别对保障钻井安全、提高钻井效率具有重要意义。目前,岩屑识别主要依赖人工经验判断,存在主观性强、耗时长和工作量大等问题。基于实际采集的岩屑图像,提出一种基于Segment Anything Model 2(SAM2)与KMeans聚类算法的岩屑识别模型,实现对岩屑颗粒的精确分割与自动聚类。同时,设计了交互式选择功能,支持工程师快速挑选目标岩屑块,显著提升岩屑块可视化与识别效率。实验结果表明,SAM2在岩屑图像分割任务中表现优异,分割精度较现有主流方法提升3%~6%。在四川威远构SX井的实际岩屑图像测试中,模型聚类识别准确率达83.9%,与人工标注结果高度一致。在典型井段的应用中,模型识别出4类主要岩屑,各类别占比分布与人工判别结果差异较小。研究结果表明,本文提出的模型方法能够有效划分不同粒径岩屑块并合理预测各类岩性占比,有助于辅助工程师快速判定地层岩性,提升钻井过程监测的客观性与实时性。 展开更多
关键词 岩屑 图像分割大模型 K-MEANS聚类算法 岩性识别 交互可视化
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适配SAM2特征融合的内窥镜结肠息肉图像分割
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作者 封筠 刘娜 +2 位作者 霍一儒 李家龙 杨靖祎 《华中科技大学学报(自然科学版)》 北大核心 2025年第12期163-170,共8页
针对内窥镜结肠息肉图像中病灶边界模糊、形态多样等挑战,基于分割任意模型2(SAM2)与U型结构,提出了SAM2-GLNet自动分割方法.首先,在编码器的预训练Hiera-L多尺度块前插入轻量化适配器,以实现参数高效微调;然后,在编解码器间引入全局与... 针对内窥镜结肠息肉图像中病灶边界模糊、形态多样等挑战,基于分割任意模型2(SAM2)与U型结构,提出了SAM2-GLNet自动分割方法.首先,在编码器的预训练Hiera-L多尺度块前插入轻量化适配器,以实现参数高效微调;然后,在编解码器间引入全局与局部特征融合及感受野模块,可整合全局语义信息与局部细节;最后,在解码器中融入空间注意力机制,进一步强化对关键区域的关注与识别能力.在4个公开结肠息肉分割数据集上的实验结果表明:与7种先进分割方法相比,SAM2-GLNet取得更具竞争力的性能,尤其在跨域CVCColonDB和ETIS数据集上,其Dice系数分别为0.829和0.808,且交并比(IoU)分别为0.755和0.734,均达到最佳水平.对比实验验证了所提出的SAM2-GLNet方法的有效性与泛化能力,消融分析则表明所设计的适配器、全局-局部融合和空间注意力模块对复杂场景和多样化目标的适应能力. 展开更多
关键词 结肠息肉自动分割 分割任意模型2(sam2) 适配器 特征融合 空间注意力
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GPT2-ICC:A data-driven approach for accurate ion channel identification using pre-trained large language models 被引量:1
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作者 Zihan Zhou Yang Yu +9 位作者 Chengji Yang Leyan Cao Shaoying Zhang Junnan Li Yingnan Zhang Huayun Han Guoliang Shi Qiansen Zhang Juwen Shen Huaiyu Yang 《Journal of Pharmaceutical Analysis》 2025年第8期1800-1809,共10页
Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Class... Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Classifier(GPT2-ICC),which effectively distinguishing ion channels from a test set containing approximately 239 times more non-ion-channel proteins.GPT2-ICC integrates representation learning with a large language model(LLM)-based classifier,enabling highly accurate identification of potential ion channels.Several potential ion channels were predicated from the unannotated human proteome,further demonstrating GPT2-ICC’s generalization ability.This study marks a significant advancement in artificial-intelligence-driven ion channel research,highlighting the adaptability and effectiveness of combining representation learning with LLMs to address the challenges of imbalanced protein sequence data.Moreover,it provides a valuable computational tool for uncovering previously uncharacterized ion channels. 展开更多
关键词 Ion channel Artificial intelligence Representation learning GPT2 Protein language model
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High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model
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作者 Xuefeng Bai Yi Li +3 位作者 Yabo Xie Qiancheng Chen Xin Zhang Jian-Rong Li 《Green Energy & Environment》 SCIE EI CAS 2025年第1期132-138,共7页
The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF str... The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design platform.High-throughput screening of catalytic performance is feasible since the large MOF structure database is available.In this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition reaction.The descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification criterion.The feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were discovered.Among them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction. 展开更多
关键词 Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition
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Diff-IDS:A Network Intrusion Detection Model Based on Diffusion Model for Imbalanced Data Samples 被引量:1
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作者 Yue Yang Xiangyan Tang +3 位作者 Zhaowu Liu Jieren Cheng Haozhe Fang Cunyi Zhang 《Computers, Materials & Continua》 2025年第3期4389-4408,共20页
With the rapid development of Internet of Things technology,the sharp increase in network devices and their inherent security vulnerabilities present a stark contrast,bringing unprecedented challenges to the field of ... With the rapid development of Internet of Things technology,the sharp increase in network devices and their inherent security vulnerabilities present a stark contrast,bringing unprecedented challenges to the field of network security,especially in identifying malicious attacks.However,due to the uneven distribution of network traffic data,particularly the imbalance between attack traffic and normal traffic,as well as the imbalance between minority class attacks and majority class attacks,traditional machine learning detection algorithms have significant limitations when dealing with sparse network traffic data.To effectively tackle this challenge,we have designed a lightweight intrusion detection model based on diffusion mechanisms,named Diff-IDS,with the core objective of enhancing the model’s efficiency in parsing complex network traffic features,thereby significantly improving its detection speed and training efficiency.The model begins by finely filtering network traffic features and converting them into grayscale images,while also employing image-flipping techniques for data augmentation.Subsequently,these preprocessed images are fed into a diffusion model based on the Unet architecture for training.Once the model is trained,we fix the weights of the Unet network and propose a feature enhancement algorithm based on feature masking to further boost the model’s expressiveness.Finally,we devise an end-to-end lightweight detection strategy to streamline the model,enabling efficient lightweight detection of imbalanced samples.Our method has been subjected to multiple experimental tests on renowned network intrusion detection benchmarks,including CICIDS 2017,KDD 99,and NSL-KDD.The experimental results indicate that Diff-IDS leads in terms of detection accuracy,training efficiency,and lightweight metrics compared to the current state-of-the-art models,demonstrating exceptional detection capabilities and robustness. 展开更多
关键词 Network traffic feature enhancement diffusion model multi-classification Algorithm 2(continued)13:end for 14:Return y
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基于24Model与RF算法的冰雪天气高速公路交通事故影响因素研究
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作者 王俊诚 解学才 孙世梅 《安全》 2025年第11期55-60,共6页
为提升冰雪天气下高速公路的行车安全水平,本文融合事故致因“2-4”模型(24Model)与机器学习方法,构建事故严重程度预测模型并识别关键致因因素。首先,以全国109起冰雪天气高速公路交通事故为样本,基于24Model系统提取15项影响因素,构... 为提升冰雪天气下高速公路的行车安全水平,本文融合事故致因“2-4”模型(24Model)与机器学习方法,构建事故严重程度预测模型并识别关键致因因素。首先,以全国109起冰雪天气高速公路交通事故为样本,基于24Model系统提取15项影响因素,构建适用于机器学习的数据集;然后,对比随机森林(RF)、K近邻与BP神经网络,建立预测模型,并对最优者实施超参数搜索与交叉验证;最后,结合重要度分析,识别影响事故严重程度的关键因素。结果表明:RF模型准确率达到0.8182,且性能最稳定;组织文化缺失为首要致因,驾驶员安全意识不足、低能见度不良天气条件及大型车辆混入亦显著加剧事故严重性。可从优化低能见度路段交通标志与照明设施、完善安全管理体系等方面提出针对性改进对策,为冰雪天气高速公路安全治理提供理论依据与管理参考。 展开更多
关键词 冰雪天气 事故致因“2-4”模型(24model) 事故严重程度 随机森林算法(RF)
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A medical image segmentation model based on SAM with an integrated local multi-scale feature encoder
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作者 DI Jing ZHU Yunlong LIANG Chan 《Journal of Measurement Science and Instrumentation》 2025年第3期359-370,共12页
Despite its remarkable performance on natural images,the segment anything model(SAM)lacks domain-specific information in medical imaging.and faces the challenge of losing local multi-scale information in the encoding ... Despite its remarkable performance on natural images,the segment anything model(SAM)lacks domain-specific information in medical imaging.and faces the challenge of losing local multi-scale information in the encoding phase.This paper presents a medical image segmentation model based on SAM with a local multi-scale feature encoder(LMSFE-SAM)to address the issues above.Firstly,based on the SAM,a local multi-scale feature encoder is introduced to improve the representation of features within local receptive field,thereby supplying the Vision Transformer(ViT)branch in SAM with enriched local multi-scale contextual information.At the same time,a multiaxial Hadamard product module(MHPM)is incorporated into the local multi-scale feature encoder in a lightweight manner to reduce the quadratic complexity and noise interference.Subsequently,a cross-branch balancing adapter is designed to balance the local and global information between the local multi-scale feature encoder and the ViT encoder in SAM.Finally,to obtain smaller input image size and to mitigate overlapping in patch embeddings,the size of the input image is reduced from 1024×1024 pixels to 256×256 pixels,and a multidimensional information adaptation component is developed,which includes feature adapters,position adapters,and channel-spatial adapters.This component effectively integrates the information from small-sized medical images into SAM,enhancing its suitability for clinical deployment.The proposed model demonstrates an average enhancement ranging from 0.0387 to 0.3191 across six objective evaluation metrics on BUSI,DDTI,and TN3K datasets compared to eight other representative image segmentation models.This significantly enhances the performance of the SAM on medical images,providing clinicians with a powerful tool in clinical diagnosis. 展开更多
关键词 segment anything model(SAM) medical image segmentation ENCODER decoder multiaxial Hadamard product module(MHPM) cross-branch balancing adapter
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Establishment of a humanized SCA2 mouse model carrying a CAA disruption preventing CAG repeat expansion in pathogenic genes
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作者 Yao Zhang Yufei Li +7 位作者 Lin Zhang Zhaoqing Li Keqin Lin Kai Huang Zhaoqing Yang Shaohui Ma Hao Sun Xiaochao Zhang 《Animal Models and Experimental Medicine》 2025年第9期1677-1687,共11页
Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion... Background:Spinocerebellar ataxia type 2(SCA2)is a neurodegenerative disease marked by significant clinical and genetic heterogeneity,primarily caused by expanded CAG mutations in the ATXN2 gene.The unstable expansion of CAG repeats disrupts the genetic stability of animal models,which is detrimental to disease research.Methods:In this study,we established a mouse model in which CAG repeats do not undergo microsatellite instability(MSI)across generations.A humanized ATXN2 cDNA with four CAA interruptions within 73 CAG expansions was inserted into the Rosa26 locus of C57BL/6J mice.A 23 CAG control mouse model was also generated to verify ATXN2 integration and expression.Results:In our model,the number of CAG repeats remained stable during transmission,with no CAG repeat expansion observed in 64 parent-to-offspring transmissions.Compared with SCA2-Q23 mice,SCA2-Q73 mice exhibited progressive motor impairment,reduced Purkinje cell count and volume(indicative of cell atrophy),and muscle atrophy.These observations in the mice suggest that the behavioral and neuropathological phenotypes may reflect the features of SCA2 patients.RNA-seq analysis of the gastrocnemius muscle in SCA2-Q73 mice showed significant changes in muscle differentiation and development gene expression at 56 weeks,with no significant differences at 16 weeks compared to SCA2-Q23 mice.The expression level of the Myf6 gene significantly changed in the muscles of aged mice.Conclusion:In summary,the establishment of this model not only provides a stable animal model for studying CAG transmission in SCA2 but also indicates that the lack of long-term neural stimulation leads to muscle atrophy. 展开更多
关键词 ATXN2 CAA interruption genetic stability mouse model SCA2
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Comparison of the pathogenicity of multiple SARS-CoV-2 variants in mouse models
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作者 Qi Lv Ming Liu +10 位作者 Feifei Qi Mingya Liu Fengdi Li Ran Deng Xujian Liang Yanfeng Xu Zhiqi Song Yiwei Yan Shuyue Li Guocui Mou Linlin Bao 《Animal Models and Experimental Medicine》 2025年第7期1302-1312,共11页
Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune press... Background:New variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to drive global epidemics and pose significant health risks.The pathogenicity of these variants evolves under immune pressure and host factors.Understanding these changes is crucial for epidemic control and variant research.Methods:Human angiotensin-converting enzyme 2(hACE2)transgenic mice were in-tranasally challenged with the original strain WH-09 and the variants Delta,Beta,and Omicron BA.1,while BALB/c mice were challenged with Omicron subvariants BA.5,BF.7,and XBB.1.To compare the pathogenicity differences among variants,we con-ducted a comprehensive analysis that included clinical symptom observation,meas-urement of viral loads in the trachea and lungs,evaluation of pulmonary pathology,analysis of immune cell infiltration,and quantification of cytokine levels.Results:In hACE2 mice,the Beta variant caused significant weight loss,severe lung inflammation,increased inflammatory and chemotactic factor secretion,greater mac-rophage and neutrophil infiltration in the lungs,and higher viral loads with prolonged shedding duration.In contrast,BA.1 showed a significant reduction in pathogenicity.The BA.5,BF.7,and XBB.1 variants were less pathogenic than the WH-09,Beta,and Delta variants when infected in BALB/c mice.This was evidenced by reduced weight loss,diminished pulmonary pathology,decreased secretion of inflammatory factors and chemokines,reduced macrophage and neutrophil infiltration,as well as lower viral loads in both the trachea and lungs.Conclusion:In hACE2 mice,the Omicron variant demonstrated the lowest pathogenic-ity,while the Beta variant exhibited the highest.Pathogenicity of the Delta variant was comparable to the original WH-09 strain.Among BALB/c mice,Omicron subvari-ants BA.5,BF.7,and XBB.1 showed no statistically significant differences in virulence. 展开更多
关键词 mice model PATHOGENICITY SARS-CoV-2 VARIANTS
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Enhancing Multi-Class Cyberbullying Classification with Hybrid Feature Extraction and Transformer-Based Models
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作者 Suliman Mohamed Fati Mohammed A.Mahdi +4 位作者 Mohamed A.G.Hazber Shahanawaj Ahamad Sawsan A.Saad Mohammed Gamal Ragab Mohammed Al-Shalabi 《Computer Modeling in Engineering & Sciences》 2025年第5期2109-2131,共23页
Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or... Cyberbullying on social media poses significant psychological risks,yet most detection systems over-simplify the task by focusing on binary classification,ignoring nuanced categories like passive-aggressive remarks or indirect slurs.To address this gap,we propose a hybrid framework combining Term Frequency-Inverse Document Frequency(TF-IDF),word-to-vector(Word2Vec),and Bidirectional Encoder Representations from Transformers(BERT)based models for multi-class cyberbullying detection.Our approach integrates TF-IDF for lexical specificity and Word2Vec for semantic relationships,fused with BERT’s contextual embeddings to capture syntactic and semantic complexities.We evaluate the framework on a publicly available dataset of 47,000 annotated social media posts across five cyberbullying categories:age,ethnicity,gender,religion,and indirect aggression.Among BERT variants tested,BERT Base Un-Cased achieved the highest performance with 93%accuracy(standard deviation across±1%5-fold cross-validation)and an average AUC of 0.96,outperforming standalone TF-IDF(78%)and Word2Vec(82%)models.Notably,it achieved near-perfect AUC scores(0.99)for age and ethnicity-based bullying.A comparative analysis with state-of-the-art benchmarks,including Generative Pre-trained Transformer 2(GPT-2)and Text-to-Text Transfer Transformer(T5)models highlights BERT’s superiority in handling ambiguous language.This work advances cyberbullying detection by demonstrating how hybrid feature extraction and transformer models improve multi-class classification,offering a scalable solution for moderating nuanced harmful content. 展开更多
关键词 Cyberbullying classification multi-class classification BERT models machine learning TF-IDF Word2Vec social media analysis transformer models
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EvoNB: A protein language model-based workflow for nanobody mutation prediction and optimization
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作者 Danyang Xiong Yongfan Ming +7 位作者 Yuting Li Shuhan Li Kexin Chen Jinfeng Liu Lili Duan Honglin Li Min Li Xiao He 《Journal of Pharmaceutical Analysis》 2025年第6期1334-1343,共10页
The identification and optimization of mutations in nanobodies are crucial for enhancing their thera-peutic potential in disease prevention and control.However,this process is often complex and time-consuming,which li... The identification and optimization of mutations in nanobodies are crucial for enhancing their thera-peutic potential in disease prevention and control.However,this process is often complex and time-consuming,which limit its widespread application in practice.In this study,we developed a work-flow,named Evolutionary-Nanobody(EvoNB),to predict key mutation sites of nanobodies by combining protein language models(PLMs)and molecular dynamic(MD)simulations.By fine-tuning the ESM2 model on a large-scale nanobody dataset,the ability of EvoNB to capture specific sequence features of nanobodies was significantly enhanced.The fine-tuned EvoNB model demonstrated higher predictive accuracy in the conserved framework and highly variable complementarity-determining regions of nanobodies.Additionally,we selected four widely representative nanobodyeantigen complexes to verify the predicted effects of mutations.MD simulations analyzed the energy changes caused by these mu-tations to predict their impact on binding affinity to the targets.The results showed that multiple mu-tations screened by EvoNB significantly enhanced the binding affinity between nanobody and its target,further validating the potential of this workflow for designing and optimizing nanobody mutations.Additionally,sequence-based predictions are generally less dependent on structural absence,allowing them to be more easily integrated with tools for structural predictions,such as AlphaFold 3.Through mutation prediction and systematic analysis of key sites,we can quickly predict the most promising variants for experimental validation without relying on traditional evolutionary or selection processes.The EvoNB workflow provides an effective tool for the rapid optimization of nanobodies and facilitates the application of PLMs in the biomedical field. 展开更多
关键词 NANOBODY Protein language models(PLMs) ESM2 model Evolutionary-nanobody(EvoNB) MD simulations AlphaFold 3
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