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基于FDS的2种纵向通风设置对公路隧道火灾疏散环境模拟结果的影响研究
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作者 李诗彤 王亮 钟珂 《中国安全生产科学技术》 北大核心 2026年第2期146-153,共8页
为评估均匀送风与射流风机这2种通风设置对公路隧道火灾疏散模拟结果的影响,采用FDS数值模拟方法,在相同几何尺寸、火源条件以及4种典型平均断面风速下构建隧道模型,分别施加2种通风设置,研究两者隧道流场特征与疏散环境的差异。研究结... 为评估均匀送风与射流风机这2种通风设置对公路隧道火灾疏散模拟结果的影响,采用FDS数值模拟方法,在相同几何尺寸、火源条件以及4种典型平均断面风速下构建隧道模型,分别施加2种通风设置,研究两者隧道流场特征与疏散环境的差异。研究结果表明:低能见度区域垂直厚度沿通风方向的变化趋势,在射流风机设置时为递增,均匀送风设置时则为递减。射流风机设置时,局部高速气流对烟气的扰动导致断面风速越大,能见度反而越低,但均匀送风设置时不存在此规律。相较射流风机设置,均匀送风设置对温度安全性预测较准确,但对能见度安全性高估显著。研究结果可为FDS数值模拟中通风设置的合理选择及疏散环境安全评估提供参考。 展开更多
关键词 隧道火灾 纵向通风断面风速 fdS纵向通风设置 人员疏散环境
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FDGformer:基于频域引导Transformer网络的红外小目标检测
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作者 杜妮妮 叶文亚 +3 位作者 刘烨 卫莎莎 王建超 徐生 《红外技术》 北大核心 2026年第2期204-211,共8页
红外小目标检测旨在从背景复杂的红外图像中检测和识别出尺寸较小的目标,在军事、安防以及无人机等领域有着广泛的应用。该任务的挑战在于红外图像通常分辨率较低、目标对比度低以及纹理模糊,导致小目标很容易被包含噪声和杂波的背景中... 红外小目标检测旨在从背景复杂的红外图像中检测和识别出尺寸较小的目标,在军事、安防以及无人机等领域有着广泛的应用。该任务的挑战在于红外图像通常分辨率较低、目标对比度低以及纹理模糊,导致小目标很容易被包含噪声和杂波的背景中所淹没。因此,如何准确地检测红外小目标的外形信息仍是目前学术界探索的热点问题。为解决上述问题,提出了一种基于频域信息引导Transformer(FDGformer)网络的红外小目标检测算法。首先采用了流行的U-net架构实现目标掩码的生成,在此基础上基于对红外图像不同层级频率域信息的探索,构建了一种基于Transformer结构的频率信息提取(FIE)模块,能够基于频域计算特征的自注意力,从而对输入特征中的特定频率成分进行增强;接着,将得到的频域增强特征作为引导设计了一种频率信息引导的空间Transformer结构,能够同时整合红外特征的全局依赖关系以及频域显著信息,从而更加准确的识别小目标的外形特征。在公开数据集上的实验结果表明,该算法相比其他先进小目标检测算法有着更高的检测精度,同时参数量更少,有效推动检测任务的实际应用。 展开更多
关键词 红外图像 弱小目标检测 TRANSFORMER 图像分割
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FDM 3D打印成型缺陷机器视觉检测方法
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作者 孙晓辉 朱洪雷 聂小春 《机电工程技术》 2026年第1期78-83,共6页
针对FDM 3D打印成型的外观缺陷机器视觉检测的需求,研究了基于邻域增强处理和频域增强处理,以及纹理统计分析的3种缺陷检测方法。邻域和频域增强检测方法是假设在规则的打印条纹中间出现的不规则形态即为打印缺陷,通过两种不同的处理途... 针对FDM 3D打印成型的外观缺陷机器视觉检测的需求,研究了基于邻域增强处理和频域增强处理,以及纹理统计分析的3种缺陷检测方法。邻域和频域增强检测方法是假设在规则的打印条纹中间出现的不规则形态即为打印缺陷,通过两种不同的处理途径滤除或削弱图像中的规则条纹以增强目标缺陷,最后分割缺陷并做颗粒分析来完成检测。纹理分析检测方法是基于窗口的灰度空间相关性与参考纹理分类识别的一种方法,该方法通过一类向量机分类器将无法归类的窗口识别为缺陷。基于NI Vision视觉库和LabVIEW开发平台,设计了3种缺陷检测方法程序。3D打印样品缺陷检测实验研究发现,当图像中的缺陷位于检测目标外侧时,邻域和频域增强检测法均无法检出,而纹理分析检测法的检出率达到100%,通用性更好;在检出相同显著缺陷的条件下,纹理分析检测法检测用时约990 ms,而邻域和频域法检测用时分别约为前者的10%和40%,具有更好的在线应用前景;在检测精度方面,频域增强检测法可达像素级精度,而邻域增强检测法和纹理分析检测法却受形态学处理单元和检测窗口的影响而精度较低。 展开更多
关键词 fdM 3D打印成型 机器视觉 缺陷检测 LABVIEW
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FDnet:基于频域分解网络的红外小目标检测
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作者 杜妮妮 叶文亚 +1 位作者 刘烨 徐生 《红外技术》 北大核心 2026年第1期62-69,共8页
在复杂背景杂波存在的情况下,检测缺乏纹理和形状信息的红外小目标成为了近年来一个备受关注的挑战。传统的模型驱动方法由于缺乏特征学习和表示的能力,对各种场景的适应性较差。同时,大部分基于深度学习的目标检测方法通过设计结构较... 在复杂背景杂波存在的情况下,检测缺乏纹理和形状信息的红外小目标成为了近年来一个备受关注的挑战。传统的模型驱动方法由于缺乏特征学习和表示的能力,对各种场景的适应性较差。同时,大部分基于深度学习的目标检测方法通过设计结构较深的网络结构来充分提取特征,但可能会在较深层失去目标的纹理结构信息,难以直接用于红外小目标检测。针对以上问题,本文按照对图像频域进行分解并分别进行处理的设计思路,提出了一种基于频域分解网络(frequency decomposition network,FDnet)的红外小目标检测算法。具体来说,FDnet首先通过高频特征提取模块分解出输入图像的高频以及低频成分,并分别送入高频分支以及低频分支用于分别提取高频边界信息以及语义信息,同时为实现两分支信息交互,本文还设计了一种空间信息聚合(spatial information aggregation,SIA)模块实现高频分支对低频分支的引导。此外,为有效捕获输入图像的空间和通道信息的注意力信息,考虑到高频信息的稀疏性,本文在高频分支引入了空间维稀疏自注意力机制(spatial-wise sparse self-attention mechanism,SSAM),同时在低频分支中引入通道维自注意力机制(CAM),从而进一步提升网络对于有效目标的感知能力。与其他现有方法相比,该算法在公开数据集上在使用较低参数量的情况下仍能保持更高的检测精度。 展开更多
关键词 红外图像 弱小目标检测 注意力机制 图像分割
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基于FDS的砖木结构文物建筑火灾特征分析
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作者 宋昊天 蒙慧玲 《建材技术与应用》 2026年第1期54-60,共7页
文物建筑是我国文化遗产的重要组成部分,是我国古代建筑技艺的现实载体,承载着古代匠人的技术和智慧,具有重要的社会经济价值、文化价值和技术价值,对我国建筑艺术和建造技术的发展有着重要的影响。我国现存文物建筑大多为砖木结构形式... 文物建筑是我国文化遗产的重要组成部分,是我国古代建筑技艺的现实载体,承载着古代匠人的技术和智慧,具有重要的社会经济价值、文化价值和技术价值,对我国建筑艺术和建造技术的发展有着重要的影响。我国现存文物建筑大多为砖木结构形式,本身具有易燃可燃的特性。加之年代久远在城市更新发展中面临着各种火灾风险,文物建筑一旦遭遇火灾,其损失是不可估量和弥补的。以刘青霞故居为研究对象,以砖木结构文物建筑的火灾特征为基础,通过分析与数值模拟相结合的方法,对研究对象的火灾蔓延特征与火灾危险进行分析,从而找出建筑防火的薄弱部位。 展开更多
关键词 文物建筑 fdS 木结构 火灾特征
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基于FDS和Pathfinder的矿井火灾疏散路径规划研究
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作者 祁云 董心悦 +3 位作者 李绪萍 祁意卿 彭涛 薛凯隆 《矿业科学学报》 北大核心 2026年第1期183-193,共11页
为研究煤矿井下火灾环境中的人员疏散路径规划问题,以山西某矿区为研究对象,运用火灾动力学模拟器(FDS)对2种矿井火灾场景(工况1和工况2)进行数值模拟,获取了烟气层高度、温度、能见度及CO浓度等关键危害参数的动态演变规律。基于此,将... 为研究煤矿井下火灾环境中的人员疏散路径规划问题,以山西某矿区为研究对象,运用火灾动力学模拟器(FDS)对2种矿井火灾场景(工况1和工况2)进行数值模拟,获取了烟气层高度、温度、能见度及CO浓度等关键危害参数的动态演变规律。基于此,将烟气危害参数与巷道固有通行难易系数耦合,建立巷道当量长度计算模型,并引入Dijkstra算法,综合烟气影响规划出最佳疏散路径。最后,采用人员疏散模拟软件(Pathfinder)对所规划路径的有效性进行模拟验证。结果表明:在2种火灾场景下,各工作面最佳疏散路径的当量长度与最短疏散时间均得到量化。具体而言,工况1的路径当量长度分别为3298.8和956.9 m,对应最短疏散时间分别为1595.8和405.8 s;工况2的路径当量长度分别为3927.2和2332.4 m,对应最短疏散时间分别为1364.8和786.8 s。最佳疏散路径的计算结果与Pathfinder模拟结果一致,验证了基于巷道当量长度的路径规划方法的科学性。研究结果为应对复杂矿井火灾环境,提供了一套理论严密且可直接应用于工程实践的应急疏散解决方案。 展开更多
关键词 矿井火灾 fdS 巷道当量长度 路径规划 PATHFINDER
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YOLO-LFD: A Lightweight and Fast Model for Forest Fire Detection
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作者 Honglin Wang Yangyang Zhang Cheng Zhu 《Computers, Materials & Continua》 2025年第2期3399-3417,共19页
Forest fires pose a serious threat to ecological balance, air quality, and the safety of both humans and wildlife. This paper presents an improved model based on You Only Look Once version 5 (YOLOv5), named YOLO Light... Forest fires pose a serious threat to ecological balance, air quality, and the safety of both humans and wildlife. This paper presents an improved model based on You Only Look Once version 5 (YOLOv5), named YOLO Lightweight Fire Detector (YOLO-LFD), to address the limitations of traditional sensor-based fire detection methods in terms of real-time performance and accuracy. The proposed model is designed to enhance inference speed while maintaining high detection accuracy on resource-constrained devices such as drones and embedded systems. Firstly, we introduce Depthwise Separable Convolutions (DSConv) to reduce the complexity of the feature extraction network. Secondly, we design and implement the Lightweight Faster Implementation of Cross Stage Partial (CSP) Bottleneck with 2 Convolutions (C2f-Light) and the CSP Structure with 3 Compact Inverted Blocks (C3CIB) modules to replace the traditional C3 modules. This optimization enhances deep feature extraction and semantic information processing, thereby significantly increasing inference speed. To enhance the detection capability for small fires, the model employs a Normalized Wasserstein Distance (NWD) loss function, which effectively reduces the missed detection rate and improves the accuracy of detecting small fire sources. Experimental results demonstrate that compared to the baseline YOLOv5s model, the YOLO-LFD model not only increases inference speed by 19.3% but also significantly improves the detection accuracy for small fire targets, with only a 1.6% reduction in overall mean average precision (mAP)@0.5. Through these innovative improvements to YOLOv5s, the YOLO-LFD model achieves a balance between speed and accuracy, making it particularly suitable for real-time detection tasks on mobile and embedded devices. 展开更多
关键词 Forest fire detection YOLOv5 LIGHTWEIGHT small object detection
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Global-local feature optimization based RGB-IR fusion object detection on drone view 被引量:1
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作者 Zhaodong CHEN Hongbing JI Yongquan ZHANG 《Chinese Journal of Aeronautics》 2026年第1期436-453,共18页
Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still st... Visible and infrared(RGB-IR)fusion object detection plays an important role in security,disaster relief,etc.In recent years,deep-learning-based RGB-IR fusion detection methods have been developing rapidly,but still struggle to deal with the complex and changing scenarios captured by drones,mainly due to two reasons:(A)RGB-IR fusion detectors are susceptible to inferior inputs that degrade performance and stability.(B)RGB-IR fusion detectors are susceptible to redundant features that reduce accuracy and efficiency.In this paper,an innovative RGB-IR fusion detection framework based on global-local feature optimization,named GLFDet,is proposed to improve the detection performance and efficiency of drone-captured objects.The key components of GLFDet include a Global Feature Optimization(GFO)module,a Local Feature Optimization(LFO)module and a Channel Separation Fusion(CSF)module.Specifically,GFO calculates the information content of the input image from the frequency domain and optimizes the features holistically.Then,LFO dynamically selects high-value features and filters out low-value features before fusion,which significantly improves the efficiency of fusion.Finally,CSF fuses the RGB and IR features across the corresponding channels,which avoids the rearrangement of the channel relationships and enhances the model stability.Extensive experimental results show that the proposed method achieves the best performance on three popular RGB-IR datasets Drone Vehicle,VEDAI,and LLVIP.In addition,GLFDet is more lightweight than other comparable models,making it more appealing to edge devices such as drones.The code is available at https://github.com/lao chen330/GLFDet. 展开更多
关键词 Object detection Deep learning RGB-IR fusion DRONES Global feature Local feature
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FFD-Clustering:An unsupervised anomaly detection method for aero-engines based on fuzzy fusion of variables and discriminative mapping of features
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作者 Zhe WANG Xuyun FU +2 位作者 Minghang ZHAO Xiangzhao XIA Shisheng ZHONG 《Chinese Journal of Aeronautics》 2025年第5期202-231,共30页
The original monitoring data from aero-engines possess characteristics such as high dimen-sionality,strong noise,and imbalance,which present substantial challenges to traditional anomalydetection methods.In response,t... The original monitoring data from aero-engines possess characteristics such as high dimen-sionality,strong noise,and imbalance,which present substantial challenges to traditional anomalydetection methods.In response,this paper proposes a method based on Fuzzy Fusion of variablesand Discriminant mapping of features for Clustering(FFD-Clustering)to detect anomalies in originalmonitoring data from Aircraft Communication Addressing and Reporting System(ACARS).Firstly,associated variables are fuzzily grouped to extract the underlying distribution characteristics and trendsfrom the data.Secondly,a multi-layer contrastive denoising-based feature Fusion Encoding Network(FEN)is designed for each variable group,which can construct representative features for each variablegroup through eliminating strong noise and complex interrelations between variables.Thirdly,a featureDiscriminative Mapping Network(DMN)based on reconstruction difference re-clustering is designed,which can distinguish dissimilar feature vectors when mapping representative features to a unified fea-ture space.Finally,the K-means clustering is used to detect the abnormal feature vectors in the unifiedfeature space.Additionally,the algorithm is capable of reconstructing identified abnormal vectors,thereby locating the abnormal variable groups.The performance of this algorithm was tested ontwo public datasets and real original monitoring data from four aero-engines'ACARS,demonstratingits superiority and application potential in aero-engine anomaly detection. 展开更多
关键词 AERO-ENGINE Anomaly detection UNSUPERVISED Fuzzy fusion Discriminativ emapping
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YOLO-SIFD:YOLO with Sliced Inference and Fractal Dimension Analysis for Improved Fire and Smoke Detection
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作者 Mariam Ishtiaq Jong-Un Won 《Computers, Materials & Continua》 2025年第3期5343-5361,共19页
Fire detection has held stringent importance in computer vision for over half a century.The development of early fire detection strategies is pivotal to the realization of safe and smart cities,inhabitable in the futu... Fire detection has held stringent importance in computer vision for over half a century.The development of early fire detection strategies is pivotal to the realization of safe and smart cities,inhabitable in the future.However,the development of optimal fire and smoke detection models is hindered by limitations like publicly available datasets,lack of diversity,and class imbalance.In this work,we explore the possible ways forward to overcome these challenges posed by available datasets.We study the impact of a class-balanced dataset to improve the fire detection capability of state-of-the-art(SOTA)vision-based models and propose the use of generative models for data augmentation,as a future work direction.First,a comparative analysis of two prominent object detection architectures,You Only Look Once version 7(YOLOv7)and YOLOv8 has been carried out using a balanced dataset,where both models have been evaluated across various evaluation metrics including precision,recall,and mean Average Precision(mAP).The results are compared to other recent fire detection models,highlighting the superior performance and efficiency of the proposed YOLOv8 architecture as trained on our balanced dataset.Next,a fractal dimension analysis gives a deeper insight into the repetition of patterns in fire,and the effectiveness of the results has been demonstrated by a windowing-based inference approach.The proposed Slicing-Aided Hyper Inference(SAHI)improves the fire and smoke detection capability of YOLOv8 for real-life applications with a significantly improved mAP performance over a strict confidence threshold.YOLOv8 with SAHI inference gives a mAP:50-95 improvement of more than 25%compared to the base YOLOv8 model.The study also provides insights into future work direction by exploring the potential of generative models like deep convolutional generative adversarial network(DCGAN)and diffusion models like stable diffusion,for data augmentation. 展开更多
关键词 Fire detection smoke detection class-balanced dataset you only look once(YOLO) slicing-aided hyper inference(SAHI) fractal dimension generative adversarial network(GAN) diffusion models
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基于FDS软件的家庭厨房天然气泄漏数值模拟
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作者 谢雨阳 郭小靖 徐松强 《煤气与热力》 2026年第1期67-71,75,共6页
为研究家庭厨房天然气泄漏的扩散规律,建立家庭厨房模型,使用火灾流体动力学模拟软件FDS,模拟不同泄漏量工况(泄漏量分别为2.5、2.0、1.5、1.0、0.5 m3/h)和不同通风面积工况(通风面积分别为0.3、0.6、0.9、1.2、1.5、1.8 m^(2))下天然... 为研究家庭厨房天然气泄漏的扩散规律,建立家庭厨房模型,使用火灾流体动力学模拟软件FDS,模拟不同泄漏量工况(泄漏量分别为2.5、2.0、1.5、1.0、0.5 m3/h)和不同通风面积工况(通风面积分别为0.3、0.6、0.9、1.2、1.5、1.8 m^(2))下天然气扩散情况。研究结果表明:不同泄漏量工况、不同通风面积工况下:冰箱底部整体上甲烷体积分数不高,远低于爆炸下限;当通风面积在1.5 m^(2)及以上时,可将顶灯处的甲烷体积分数控制在爆炸下限以下;发生泄漏25 s左右均可触发报警器报警。对于家庭厨房天然气泄漏场景,天然气泄漏后向上运动并在上层积聚。在无机械通风的情况下,泄漏量和通风面积决定了厨房内不同位置的积聚程度。文末附有天然气泄漏示踪粒子展示视频,可扫二维码观看。 展开更多
关键词 天然气泄漏 扩散 家庭厨房 fdS软件
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Construction and application of the RPA-LFD rapid detection method for Glugea plecoglossi
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作者 Jiaxue SONG Ruixin FENG +4 位作者 Yunfei PANG Qingyue XU Dong ZHENG Yunji XIU Shun ZHOU 《Journal of Oceanology and Limnology》 2025年第5期1647-1653,共7页
Glugea plecoglossi,a microsporidia of the Glugea genus,can cause an infamous disease Plecoglossus altivelis in East Asia,resulting in heavy economic losses.At present,the main diagnostic methods for this disease inclu... Glugea plecoglossi,a microsporidia of the Glugea genus,can cause an infamous disease Plecoglossus altivelis in East Asia,resulting in heavy economic losses.At present,the main diagnostic methods for this disease include microscopy examination,quantitative real-time PCR,and loop-mediated isothermal amplification-lateral flow dipstick(LAMP-LFD).In this study,a recombinase polymerase amplification-lateral flow dipstick(RPA-LFD)method,targeting the beta-tubulin gene,was developed to detect G.plecoglossi,three sets of primers and probes were designed and screened,after which the initial reaction system was established.The RPA-LFD method for G.plecoglossi could complete nucleic acid amplification at 39℃ for 10 min,after which the amplification product was dropped on the LFD strip,and the results could then be observed within 5 min.A specificity assay revealed that there was no cross reactivity with other protozoa except G.plecoglossi.A sensitivity assay revealed that the detection limit was 9.38×10^(-6) ng/μL,which was more sensitive than that of conventional PCR.Compared with conventional detection methods,the novel RPA-LFD method has the advantages of simple operation,short operation time,high sensitivity,and high specificity for G.plecoglossi detection,indicating its potential use in rapid field detection of G.plecoglossi. 展开更多
关键词 Glugea plecoglossi recombinase polymerase amplification lateral flow dipstick rapid detection Plecoglossus altivelis
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Explore Advanced Hybrid Deep Learning for Enhanced Wireless Signal Detection in 5G OFDM Systems
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作者 Ahmed K.Ali Jungpil Shin +1 位作者 Yujin Lim Da-Hun Seong 《Computer Modeling in Engineering & Sciences》 2025年第12期4245-4278,共34页
Single-signal detection in orthogonal frequency-divisionmultiplexing(OFDM)systems presents a challenge due to the time-varying nature of wireless channels.Although conventional methods have limitations,particularly in... Single-signal detection in orthogonal frequency-divisionmultiplexing(OFDM)systems presents a challenge due to the time-varying nature of wireless channels.Although conventional methods have limitations,particularly inmulti-inputmultioutput orthogonal frequency divisionmultiplexing(MIMO-OFDM)systems,this paper addresses this problem by exploring advanced deep learning approaches for combined channel estimation and signal detection.Specifically,we propose two hybrid architectures that integrate a convolutional neural network(CNN)with a recurrent neural network(RNN),namely,CNN-long short-term memory(CNN-LSTM)and CNN-bidirectional-LSTM(CNNBi-LSTM),designed to enhance signal detection performance in MIMO-OFDM systems.The proposed CNN-LSTM and CNN-Bi-LSTM architectures are evaluated and compared with both traditional methods and standalone deep learning models.Training was conducted offline using a dataset generated from a 2×2 MIMO-OFDM system with a 3GPP 5G channel model.The trained models are evaluated using accuracy,loss,and computational time,and further analysis of signal detection performance is based on bit error rate,optimal cyclic prefix length,and optimal pilot subcarrier configurations under various noise conditions and channel uncertainty scenarios.The results demonstrate that the proposed CNN-based architectures,particularly the CNN-Bi-LSTM trained model,significantly reduce the need for pilot and cyclic prefix symbols while delivering superior performance,especially at SNRs.All the hybrid deep learning architectures(CNN-LSTM,CNN-Bi-LSTM)demonstrated greater robustness and adaptability under dynamic channel conditions,outperforming conventional methods and benchmark deep learning architectures.These results indicate the effectiveness of CNN-based feature extractors in learning generalized spatial patterns,positioning these hybrid models as highly efficient and reliable solutions for MIMO-OFDM signal detection in 5G and future wireless communication systems. 展开更多
关键词 Signal detection deep learning CNN-LSTM CNN-Bi-LSTM MIMO-OfdM channel estimation wireless communications time-varying channels pilot reduction
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Leveraging the WFD2020 Dataset for Multi-Class Detection of Wheat Fungal Diseases with YOLOv8 and Faster R-CNN
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作者 Shivani Sood Harjeet Singh +1 位作者 Surbhi Bhatia Khan Ahlam Almusharraf 《Computers, Materials & Continua》 2025年第8期2751-2787,共37页
Wheat fungal infections pose a danger to the grain quality and crop productivity.Thus,prompt and precise diagnosis is essential for efficient crop management.This study used the WFD2020 image dataset,which is availabl... Wheat fungal infections pose a danger to the grain quality and crop productivity.Thus,prompt and precise diagnosis is essential for efficient crop management.This study used the WFD2020 image dataset,which is available to everyone,to look into howdeep learningmodels could be used to find powdery mildew,leaf rust,and yellow rust,which are three common fungal diseases in Punjab,India.We changed a few hyperparameters to test TensorFlowbased models,such as SSD and Faster R-CNN with ResNet50,ResNet101,and ResNet152 as backbones.Faster R-CNN with ResNet50 achieved amean average precision(mAP)of 0.68 among these models.We then used the PyTorch-based YOLOv8 model,which significantly outperformed the previous methods with an impressive mAP of 0.99.YOLOv8 proved to be a beneficial approach for the early-stage diagnosis of fungal diseases,especially when it comes to precisely identifying diseased areas and various object sizes in images.Problems,such as class imbalance and possible model overfitting,persisted despite these developments.The results show that YOLOv8 is a good automated disease diagnosis tool that helps farmers quickly find and treat fungal infections using image-based systems. 展开更多
关键词 Wheat crop detection and classification fungal disease rust diseases Faster R-CNN deep learning computer vision precision agriculture
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A Comprehensive Literature Review on YOLO-Based Small Object Detection:Methods,Challenges,and Future Trends
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作者 Hui Yu Jun Liu Mingwei Lin 《Computers, Materials & Continua》 2026年第4期258-309,共52页
Small object detection has been a focus of attention since the emergence of deep learning-based object detection.Although classical object detection frameworks have made significant contributions to the development of... Small object detection has been a focus of attention since the emergence of deep learning-based object detection.Although classical object detection frameworks have made significant contributions to the development of object detection,there are still many issues to be resolved in detecting small objects due to the inherent complexity and diversity of real-world visual scenes.In particular,the YOLO(You Only Look Once)series of detection models,renowned for their real-time performance,have undergone numerous adaptations aimed at improving the detection of small targets.In this survey,we summarize the state-of-the-art YOLO-based small object detection methods.This review presents a systematic categorization of YOLO-based approaches for small-object detection,organized into four methodological avenues,namely attention-based feature enhancement,detection-head optimization,loss function,and multi-scale feature fusion strategies.We then examine the principal challenges addressed by each category.Finally,we analyze the performance of thesemethods on public benchmarks and,by comparing current approaches,identify limitations and outline directions for future research. 展开更多
关键词 Small object detection YOLO real-time detection feature fusion deep learning
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AI-Powered Anomaly Detection and Cybersecurity in Healthcare IoT with Fog-Edge
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作者 Fatima Al-Quayed 《Computer Modeling in Engineering & Sciences》 2026年第1期1339-1372,共34页
The rapid proliferation of Internet of Things(IoT)devices in critical healthcare infrastructure has introduced significant security and privacy challenges that demand innovative,distributed architectural solutions.Thi... The rapid proliferation of Internet of Things(IoT)devices in critical healthcare infrastructure has introduced significant security and privacy challenges that demand innovative,distributed architectural solutions.This paper proposes FE-ACS(Fog-Edge Adaptive Cybersecurity System),a novel hierarchical security framework that intelligently distributes AI-powered anomaly detection algorithms across edge,fog,and cloud layers to optimize security efficacy,latency,and privacy.Our comprehensive evaluation demonstrates that FE-ACS achieves superior detection performance with an AUC-ROC of 0.985 and an F1-score of 0.923,while maintaining significantly lower end-to-end latency(18.7 ms)compared to cloud-centric(152.3 ms)and fog-only(34.5 ms)architectures.The system exhibits exceptional scalability,supporting up to 38,000 devices with logarithmic performance degradation—a 67×improvement over conventional cloud-based approaches.By incorporating differential privacy mechanisms with balanced privacy-utility tradeoffs(ε=1.0–1.5),FE-ACS maintains 90%–93%detection accuracy while ensuring strong privacy guarantees for sensitive healthcare data.Computational efficiency analysis reveals that our architecture achieves a detection rate of 12,400 events per second with only 12.3 mJ energy consumption per inference.In healthcare risk assessment,FE-ACS demonstrates robust operational viability with low patient safety risk(14.7%)and high system reliability(94.0%).The proposed framework represents a significant advancement in distributed security architectures,offering a scalable,privacy-preserving,and real-time solution for protecting healthcare IoT ecosystems against evolving cyber threats. 展开更多
关键词 AI-powered anomaly detection healthcare IoT fog computing CYBERSECURITY intrusion detection
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A Comparative Benchmark of Deep Learning Architectures for AI-Assisted Breast Cancer Detection in Mammography Using the MammosighTR Dataset:A Nationwide Turkish Screening Study(2016–2022)
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作者 Nuh Azginoglu 《Computer Modeling in Engineering & Sciences》 2026年第1期1151-1173,共23页
Breast cancer screening programs rely heavily on mammography for early detection;however,diagnostic performance is strongly affected by inter-reader variability,breast density,and the limitations of conven-tional comp... Breast cancer screening programs rely heavily on mammography for early detection;however,diagnostic performance is strongly affected by inter-reader variability,breast density,and the limitations of conven-tional computer-aided detection systems.Recent advances in deep learning have enabled more robust and scalable solutions for large-scale screening,yet a systematic comparison of modern object detection architectures on nationally representative datasets remains limited.This study presents a comprehensive quantitative comparison of prominent deep learning–based object detection architectures for Artificial Intelligence-assisted mammography analysis using the MammosighTR dataset,developed within the Turkish National Breast Cancer Screening Program.The dataset comprises 12,740 patient cases collected between 2016 and 2022,annotated with BI-RADS categories,breast density levels,and lesion localization labels.A total of 31 models were evaluated,including One-Stage,Two-Stage,and Transformer-based architectures,under a unified experimental framework at both patient and breast levels.The results demonstrate that Two-Stage architectures consistently outperform One-Stage models,achieving approximately 2%–4%higher Macro F1-Scores and more balanced precision–recall trade-offs,with Double-Head R-CNN and Dynamic R-CNN yielding the highest overall performance(Macro F1≈0.84–0.86).This advantage is primarily attributed to the region proposal mechanism and improved class balance inherent to Two-Stage designs.One-Stage detectors exhibited higher sensitivity and faster inference,reaching Recall values above 0.88,but experienced minor reductions in Precision and overall accuracy(≈1%–2%)compared with Two-Stage models.Among Transformer-based architectures,Deformable DEtection TRansformer demonstrated strong robustness and consistency across datasets,achieving Macro F1-Scores comparable to CNN-based detectors(≈0.83–0.85)while exhibiting minimal performance degradation under distributional shifts.Breast density–based analysis revealed increased misclassification rates in medium-density categories(types B and C),whereas Transformer-based architectures maintained more stable performance in high-density type D tissue.These findings quantitatively confirm that both architectural design and tissue characteristics play a decisive role in diagnostic accuracy.Overall,the study provides a reproducible benchmark and highlights the potential of hybrid approaches that combine the accuracy of Two-Stage detectors with the contextual modeling capability of Transformer architectures for clinically reliable breast cancer screening systems. 展开更多
关键词 Deep learning MAMMOGRAPHY breast cancer detection object detection BI-RADS classification
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YOLO-SDW: Traffic Sign Detection Algorithm Based on YOLOv8s Skip Connection and Dynamic Convolution
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作者 Qing Guo Juwei Zhang Bingyi Ren 《Computers, Materials & Continua》 2026年第1期1433-1452,共20页
Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakt... Traffic sign detection is an important part of autonomous driving,and its recognition accuracy and speed are directly related to road traffic safety.Although convolutional neural networks(CNNs)have made certain breakthroughs in this field,in the face of complex scenes,such as image blur and target occlusion,the traffic sign detection continues to exhibit limited accuracy,accompanied by false positives and missed detections.To address the above problems,a traffic sign detection algorithm,You Only Look Once-based Skip Dynamic Way(YOLO-SDW)based on You Only Look Once version 8 small(YOLOv8s),is proposed.Firstly,a Skip Connection Reconstruction(SCR)module is introduced to efficiently integrate fine-grained feature information and enhance the detection accuracy of the algorithm in complex scenes.Secondly,a C2f module based on Dynamic Snake Convolution(C2f-DySnake)is proposed to dynamically adjust the receptive field information,improve the algorithm’s feature extraction ability for blurred or occluded targets,and reduce the occurrence of false detections and missed detections.Finally,the Wise Powerful IoU v2(WPIoUv2)loss function is proposed to further improve the detection accuracy of the algorithm.Experimental results show that the average precision mAP@0.5 of YOLO-SDW on the TT100K dataset is 89.2%,and mAP@0.5:0.95 is 68.5%,which is 4%and 3.3%higher than the YOLOv8s baseline,respectively.YOLO-SDW ensures real-time performance while having higher accuracy. 展开更多
关键词 Traffic sign detection YOLOv8 object detection deep learning
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An Efficient and Dynamic Framework for Multi-Scale Target Detection of Underwater Organisms
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作者 LI Zhuang LI Guixiang +1 位作者 SONG Xiangyang WANG Xinhua 《Journal of Ocean University of China》 2026年第1期150-160,共11页
The continuous decrease in global fishery resources has increased the importance of precise and efficient underwater fish monitoring technology.First,this study proposes an improved underwater target detection framewo... The continuous decrease in global fishery resources has increased the importance of precise and efficient underwater fish monitoring technology.First,this study proposes an improved underwater target detection framework based on YOLOv8,with the aim of enhancing detection accuracy and the ability to recognize multi-scale targets in blurry and complex underwater environments.A streamlined Vision Transformer(ViT)model is used as the feature extraction backbone,which retains global self-attention feature extraction and accelerates training efficiency.In addition,a detection head named Dynamic Head(DyHead)is introduced,which enhances the efficiency of processing various target sizes through multi-scale feature fusion and adaptive attention modules.Furthermore,a dynamic loss function adjustment method called SlideLoss is employed.This method utilizes sliding window technology to adaptively adjust parameters,which optimizes the detection of challenging targets.The experimental results on the RUOD dataset show that the proposed improved model not only significantly enhances the accuracy of target detection but also increases the efficiency of target detection. 展开更多
关键词 underwater target detection complex underwater environment YOLOv8 object detection
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CoPt graphitic nanozyme enabled naked-eye identification and colorimetric/fluorescent dual-mode detection of phenylenediamine isomers
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作者 Luyao Guan Zhaoxin Wang +2 位作者 Shengkai Li Phouphien Keoingthong Zhuo Chen 《Chinese Chemical Letters》 2026年第2期407-414,共8页
Simultaneous identification and quantitative detection of phenylenediamine(PDA)isomers,including o-phenylenediamine(OPD),m-phenylenediamine(MPD),and p-phenylenediamine(PPD),are essential for environmental risk assessm... Simultaneous identification and quantitative detection of phenylenediamine(PDA)isomers,including o-phenylenediamine(OPD),m-phenylenediamine(MPD),and p-phenylenediamine(PPD),are essential for environmental risk assessment and human health protection.However,current visual detection methods can only distinguish individual PDA isomers and failed to identify binary or ternary mixtures.Herein,a highly active and ultrastable peroxidase(POD)-like CoPt graphitic nanozyme was used for naked-eye identification and colorimetric/fluorescent(FL)dual-mode quantitative detection of PDA isomers.The CoPt@G nanozyme effectively catalyzed the oxidation of OPD,MPD,PPD,OPD+PPD,OPD+MPD,MPD+PPD and OPD+MPD+PPD into yellow,colorless,lilac,yellow,yellow,wine red and reddish-brown products,respectively,in the presence of H_(2)O_(2).Thus,the MPD,PPD,MPD+PPD and OPD+MPD+PPD were easily identified based on the distinct color of their oxidation products,and the OPD,OPD+PPD,OPD+MPD could be further identified by the additional addition of MPD or PPD.Subsequently,CoPt@G/H_(2)O_(2)-,a 3,3′,5,5′-tetramethylbenzidine(TMB)/CoPt@G/H_(2)O_(2)-,and MPD/CoPt@G/H_(2)O_(2)-enabled colorimetric/FL dual-mode platforms for the quantitative detection of OPD,MPD and PPD were proposed.The experimental results illustrated that the constructed sensing platforms exhibit satisfactory sensitivity,comparable to that reported in previous studies.Finally,the evaluation of PDAs in water samples was realized,yielding satisfactory recoveries.This work expanded the application prospects of nanozymes in assessing environmental risks and protection of human security. 展开更多
关键词 Copt graphitic nanozyme Phenylenediamine isomers Naked-eye identification Colorimetric detection Fluorescent detection
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