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A Hybrid Deep Learning Multi-Class Classification Model for Alzheimer’s Disease Using Enhanced MRI Images
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作者 Ghadah Naif Alwakid 《Computers, Materials & Continua》 2026年第1期797-821,共25页
Alzheimer’s Disease(AD)is a progressive neurodegenerative disorder that significantly affects cognitive function,making early and accurate diagnosis essential.Traditional Deep Learning(DL)-based approaches often stru... Alzheimer’s Disease(AD)is a progressive neurodegenerative disorder that significantly affects cognitive function,making early and accurate diagnosis essential.Traditional Deep Learning(DL)-based approaches often struggle with low-contrast MRI images,class imbalance,and suboptimal feature extraction.This paper develops a Hybrid DL system that unites MobileNetV2 with adaptive classification methods to boost Alzheimer’s diagnosis by processing MRI scans.Image enhancement is done using Contrast-Limited Adaptive Histogram Equalization(CLAHE)and Enhanced Super-Resolution Generative Adversarial Networks(ESRGAN).A classification robustness enhancement system integrates class weighting techniques and a Matthews Correlation Coefficient(MCC)-based evaluation method into the design.The trained and validated model gives a 98.88%accuracy rate and 0.9614 MCC score.We also performed a 10-fold cross-validation experiment with an average accuracy of 96.52%(±1.51),a loss of 0.1671,and an MCC score of 0.9429 across folds.The proposed framework outperforms the state-of-the-art models with a 98%weighted F1-score while decreasing misdiagnosis results for every AD stage.The model demonstrates apparent separation abilities between AD progression stages according to the results of the confusion matrix analysis.These results validate the effectiveness of hybrid DL models with adaptive preprocessing for early and reliable Alzheimer’s diagnosis,contributing to improved computer-aided diagnosis(CAD)systems in clinical practice. 展开更多
关键词 Alzheimer’s disease deep learning MRI images MobileNetV2 contrast-limited adaptive histogram equalization(CLAHE) enhanced super-resolution generative adversarial networks(ESRGAN) multi-class classification
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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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Multi-Class Classification Methods of Cost-Conscious LS-SVM for Fault Diagnosis of Blast Furnace 被引量:15
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作者 LIU Li-mei WANG An-na SHA Mo ZHAO Feng-yun 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第10期17-23,33,共8页
Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discre... Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-con- scious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectbrs and better general- ization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage ia used to select sample randomly. The proposed new metbod raises the sped of diagnosis, optimizes the classifieation scraraey and has good generalization ability for fault diagnosis of the application of blast furnace. 展开更多
关键词 blast furnace fault diagnosis eosc-conscious LS-SVM multi-class classification
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Multi-class Classification Methods of Enhanced LS-TWSVM for Strip Steel Surface Defects 被引量:4
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作者 Mao-xiang CHU An-na WANG +1 位作者 Rong-fen GONG Mo SHA 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2014年第2期174-180,共7页
Considering strip steel surface defect samples, a multi-class classification method was proposed based on enhanced least squares twin support vector machines (ELS-TWSVMs) and binary tree. Firstly, pruning region sam... Considering strip steel surface defect samples, a multi-class classification method was proposed based on enhanced least squares twin support vector machines (ELS-TWSVMs) and binary tree. Firstly, pruning region samples center method with adjustable pruning scale was used to prune data samples. This method could reduce classifierr s training time and testing time. Secondly, ELS-TWSVM was proposed to classify the data samples. By introducing error variable contribution parameter and weight parameter, ELS-TWSVM could restrain the impact of noise sam- ples and have better classification accuracy. Finally, multi-class classification algorithms of ELS-TWSVM were pro- posed by combining ELS-TWSVM and complete binary tree. Some experiments were made on two-dimensional data- sets and strip steel surface defect datasets. The experiments showed that the multi-class classification methods of ELS-TWSVM had higher classification speed and accuracy for the datasets with large-scale, unbalanced and noise samples. 展开更多
关键词 multi-class classification least squares twin support vector machine error variable contribution WEIGHT binary tree strip steel surface
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A combined algorithm of K-means and MTRL for multi-class classification 被引量:2
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作者 XUE Mengfan HAN Lei PENG Dongliang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第5期875-885,共11页
The basic idea of multi-class classification is a disassembly method,which is to decompose a multi-class classification task into several binary classification tasks.In order to improve the accuracy of multi-class cla... The basic idea of multi-class classification is a disassembly method,which is to decompose a multi-class classification task into several binary classification tasks.In order to improve the accuracy of multi-class classification in the case of insufficient samples,this paper proposes a multi-class classification method combining K-means and multi-task relationship learning(MTRL).The method first uses the split method of One vs.Rest to disassemble the multi-class classification task into binary classification tasks.K-means is used to down sample the dataset of each task,which can prevent over-fitting of the model while reducing training costs.Finally,the sampled dataset is applied to the MTRL,and multiple binary classifiers are trained together.With the help of MTRL,this method can utilize the inter-task association to train the model,and achieve the purpose of improving the classification accuracy of each binary classifier.The effectiveness of the proposed approach is demonstrated by experimental results on the Iris dataset,Wine dataset,Multiple Features dataset,Wireless Indoor Localization dataset and Avila dataset. 展开更多
关键词 machine LEARNING multi-class classification K-MEANS MULTI-TASK RELATIONSHIP LEARNING (MTRL) OVER-FITTING
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Multi-class classification method for strip steel surface defects based on support vector machine with adjustable hyper-sphere 被引量:2
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作者 Mao-xiang Chu Xiao-ping Liu +1 位作者 Rong-fen Gong Jie Zhao 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第7期706-716,共11页
Focusing on strip steel surface defects classification, a novel support vector machine with adjustable hyper-sphere (AHSVM) is formulated. Meanwhile, a new multi-class classification method is proposed. Originated f... Focusing on strip steel surface defects classification, a novel support vector machine with adjustable hyper-sphere (AHSVM) is formulated. Meanwhile, a new multi-class classification method is proposed. Originated from support vector data description, AHSVM adopts hyper-sphere to solve classification problem. AHSVM can obey two principles: the margin maximization and inner-class dispersion minimization. Moreover, the hyper-sphere of AHSVM is adjustable, which makes the final classification hyper-sphere optimal for training dataset. On the other hand, AHSVM is combined with binary tree to solve multi-class classification for steel surface defects. A scheme of samples pruning in mapped feature space is provided, which can reduce the number of training samples under the premise of classification accuracy, resulting in the improvements of classification speed. Finally, some testing experiments are done for eight types of strip steel surface defects. Experimental results show that multi-class AHSVM classifier exhibits satisfactory results in classification accuracy and efficiency. 展开更多
关键词 Strip steel surface defect multi-class classification Supporting vector machine Adjustable hyper-sphere
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Multi-class classification method for steel surface defects with feature noise 被引量:2
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作者 Mao-xiang Chu Yao Feng +1 位作者 Yong-hui Yang Xin Deng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2021年第3期303-315,共13页
Defect classification is the key task of a steel surface defect detection system.The current defect classification algorithms have not taken the feature noise into consideration.In order to reduce the adverse impact o... Defect classification is the key task of a steel surface defect detection system.The current defect classification algorithms have not taken the feature noise into consideration.In order to reduce the adverse impact of feature noise,an anti-noise multi-class classification method was proposed for steel surface defects.On the one hand,a novel anti-noise support vector hyper-spheres(ASVHs)classifier was formulated.For N types of defects,the ASVHs classifier built N hyper-spheres.These hyper-spheres were insensitive to feature and label noise.On the other hand,in order to reduce the costs of online time and storage space,the defect samples were pruned by support vector data description with parameter iteration adjustment strategy.In the end,the ASVHs classifier was built with sparse defect samples set and auxiliary information.Experimental results show that the novel multi-class classification method has high efficiency and accuracy for corrupted defect samples in steel surface. 展开更多
关键词 Steel surface defect multi-class classification Anti-noise support vector hyper-sphere Parameter iteration adjustment Feature noise
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Power Quality Disturbance Classification Method Based on Wavelet Transform and SVM Multi-class Algorithms 被引量:1
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作者 Xiao Fei 《Energy and Power Engineering》 2013年第4期561-565,共5页
The accurate identification and classification of various power quality disturbances are keys to ensuring high-quality electrical energy. In this study, the statistical characteristics of the disturbance signal of wav... The accurate identification and classification of various power quality disturbances are keys to ensuring high-quality electrical energy. In this study, the statistical characteristics of the disturbance signal of wavelet transform coefficients and wavelet transform energy distribution constitute feature vectors. These vectors are then trained and tested using SVM multi-class algorithms. Experimental results demonstrate that the SVM multi-class algorithms, which use the Gaussian radial basis function, exponential radial basis function, and hyperbolic tangent function as basis functions, are suitable methods for power quality disturbance classification. 展开更多
关键词 Power Quality DISTURBANCE classification WAVELET TRANSFORM SVM multi-class ALGORITHMS
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Deep Architectural Classification of Dental Pathologies Using Orthopantomogram Imaging
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作者 Arham Adnan Muhammad Tuaha Rizwan +2 位作者 Hafiz Muhammad Attaullah Shakila Basheer Mohammad Tabrez Quasim 《Computers, Materials & Continua》 2025年第12期5073-5091,共19页
Artificial intelligence(AI),particularly deep learning algorithms utilizing convolutional neural networks,plays an increasingly pivotal role in enhancing medical image examination.It demonstrates the potential for imp... Artificial intelligence(AI),particularly deep learning algorithms utilizing convolutional neural networks,plays an increasingly pivotal role in enhancing medical image examination.It demonstrates the potential for improving diagnostic accuracy within dental care.Orthopantomograms(OPGs)are essential in dentistry;however,their manual interpretation is often inconsistent and tedious.To the best of our knowledge,this is the first comprehensive application of YOLOv5m for the simultaneous detection and classification of six distinct dental pathologies using panoramic OPG images.The model was trained and refined on a custom dataset that began with 232 panoramic radiographs and was later expanded to 604 samples.These included annotated subclasses representing Caries,Infection,Impacted Teeth,Fractured Teeth,Broken Crowns,and Healthy conditions.The training was performed using GPU resources alongside tuned hyperparameters of batch size,learning rate schedule,and early stopping tailored for generalization to prevent overfitting.Evaluation on a held-out test set showed strong performance in the detection and localization of various dental pathologies and robust overall accuracy.At an IoU of 0.5,the system obtained a mean precision of 94.22%and recall of 90.42%,with mAP being 93.71%.This research confirms the use of YOLOv5m as a robust,highly efficient AI technology for the analysis of dental pathologies using OPGs,providing a clinically useful solution to enhance workflow efficiency and aid in sustaining consistency in complex multi-dimensional case evaluations. 展开更多
关键词 Medical image analysis orthopantomogram convolutional neural networks YOLOv5m multi-class classification dental pathology detection
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A Novel Combinational Convolutional Neural Network for Automatic Food-Ingredient Classification 被引量:6
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作者 Lili Pan Cong Li +2 位作者 Samira Pouyanfar Rongyu Chen Yan Zhou 《Computers, Materials & Continua》 SCIE EI 2020年第2期731-746,共16页
With the development of deep learning and Convolutional Neural Networks(CNNs),the accuracy of automatic food recognition based on visual data have significantly improved.Some research studies have shown that the deepe... With the development of deep learning and Convolutional Neural Networks(CNNs),the accuracy of automatic food recognition based on visual data have significantly improved.Some research studies have shown that the deeper the model is,the higher the accuracy is.However,very deep neural networks would be affected by the overfitting problem and also consume huge computing resources.In this paper,a new classification scheme is proposed for automatic food-ingredient recognition based on deep learning.We construct an up-to-date combinational convolutional neural network(CBNet)with a subnet merging technique.Firstly,two different neural networks are utilized for learning interested features.Then,a well-designed feature fusion component aggregates the features from subnetworks,further extracting richer and more precise features for image classification.In order to learn more complementary features,the corresponding fusion strategies are also proposed,including auxiliary classifiers and hyperparameters setting.Finally,CBNet based on the well-known VGGNet,ResNet and DenseNet is evaluated on a dataset including 41 major categories of food ingredients and 100 images for each category.Theoretical analysis and experimental results demonstrate that CBNet achieves promising accuracy for multi-class classification and improves the performance of convolutional neural networks. 展开更多
关键词 Food-ingredient recognition multi-class classification deep learning convolutional neural network feature fusion
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Multi-Class Support Vector Machine Classifier Based on Jeffries-Matusita Distance and Directed Acyclic Graph 被引量:1
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作者 Miao Zhang Zhen-Zhou Lai +1 位作者 Dan Li Yi Shen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第5期113-118,共6页
Based on the framework of support vector machines (SVM) using one-against-one (OAO) strategy, a new multi-class kernel method based on directed aeyclie graph (DAG) and probabilistic distance is proposed to raise... Based on the framework of support vector machines (SVM) using one-against-one (OAO) strategy, a new multi-class kernel method based on directed aeyclie graph (DAG) and probabilistic distance is proposed to raise the multi-class classification accuracies. The topology structure of DAG is constructed by rearranging the nodes' sequence in the graph. DAG is equivalent to guided operating SVM on a list, and the classification performance depends on the nodes' sequence in the graph. Jeffries-Matusita distance (JMD) is introduced to estimate the separability of each class, and the implementation list is initialized with all classes organized according to certain sequence in the list. To testify the effectiveness of the proposed method, numerical analysis is conducted on UCI data and hyperspectral data. Meanwhile, comparative studies using standard OAO and DAG classification methods are also conducted and the results illustrate better performance and higher accuracy of the orooosed JMD-DAG method. 展开更多
关键词 multi-class classification support vector machine directed acyclic graph Jeffries-Matusitadistance hyperspcctral data
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LLE-BASED CLASSIFICATION ALGORITHM FOR MMW RADAR TARGET RECOGNITION 被引量:1
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作者 Luo Lei Li Yuehua Luan Yinghong 《Journal of Electronics(China)》 2010年第1期139-144,共6页
In this paper,a new multiclass classification algorithm is proposed based on the idea of Locally Linear Embedding(LLE),to avoid the defect of traditional manifold learning algorithms,which can not deal with new sample... In this paper,a new multiclass classification algorithm is proposed based on the idea of Locally Linear Embedding(LLE),to avoid the defect of traditional manifold learning algorithms,which can not deal with new sample points.The algorithm defines an error as a criterion by computing a sample's reconstruction weight using LLE.Furthermore,the existence and characteristics of low dimensional manifold in range-profile time-frequency information are explored using manifold learning algorithm,aiming at the problem of target recognition about high range resolution MilliMeter-Wave(MMW) radar.The new algorithm is applied to radar target recognition.The experiment results show the algorithm is efficient.Compared with other classification algorithms,our method improves the recognition precision and the result is not sensitive to input parameters. 展开更多
关键词 Manifold learning Locally Linear Embedding(LLE) multi-class classification MilliMeter-Wave(MMW) Target recognition
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Exploiting Empirical Variance for Data Stream Classification
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作者 ZIA-UR REHMAN Muhammad 李天瑞 李涛 《Journal of Shanghai Jiaotong university(Science)》 EI 2012年第2期245-250,共6页
Classification,using the decision tree algorithm,is a widely studied problem in data streams.The challenge is when to split a decision node into multiple leaves.Concentration inequalities,that exploit variance informa... Classification,using the decision tree algorithm,is a widely studied problem in data streams.The challenge is when to split a decision node into multiple leaves.Concentration inequalities,that exploit variance information such as Bernstein's and Bennett's inequalities,are often substantially strict as compared with Hoeffding's bound which disregards variance.Many machine learning algorithms for stream classification such as very fast decision tree(VFDT) learner,AdaBoost and support vector machines(SVMs),use the Hoeffding's bound as a performance guarantee.In this paper,we propose a new algorithm based on the recently proposed empirical Bernstein's bound to achieve a better probabilistic bound on the accuracy of the decision tree.Experimental results on four synthetic and two real world data sets demonstrate the performance gain of our proposed technique. 展开更多
关键词 Hoeffding and Bernstein’s bounds data stream classification decision tree anytime algorithm
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A YOLOv11-Based Deep Learning Framework for Multi-Class Human Action Recognition
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作者 Nayeemul Islam Nayeem Shirin Mahbuba +4 位作者 Sanjida Islam Disha Md Rifat Hossain Buiyan Shakila Rahman M.Abdullah-Al-Wadud Jia Uddin 《Computers, Materials & Continua》 2025年第10期1541-1557,共17页
Human activity recognition is a significant area of research in artificial intelligence for surveillance,healthcare,sports,and human-computer interaction applications.The article benchmarks the performance of You Only... Human activity recognition is a significant area of research in artificial intelligence for surveillance,healthcare,sports,and human-computer interaction applications.The article benchmarks the performance of You Only Look Once version 11-based(YOLOv11-based)architecture for multi-class human activity recognition.The article benchmarks the performance of You Only Look Once version 11-based(YOLOv11-based)architecture for multi-class human activity recognition.The dataset consists of 14,186 images across 19 activity classes,from dynamic activities such as running and swimming to static activities such as sitting and sleeping.Preprocessing included resizing all images to 512512 pixels,annotating them in YOLO’s bounding box format,and applying data augmentation methods such as flipping,rotation,and cropping to enhance model generalization.The proposed model was trained for 100 epochs with adaptive learning rate methods and hyperparameter optimization for performance improvement,with a mAP@0.5 of 74.93%and a mAP@0.5-0.95 of 64.11%,outperforming previous versions of YOLO(v10,v9,and v8)and general-purpose architectures like ResNet50 and EfficientNet.It exhibited improved precision and recall for all activity classes with high precision values of 0.76 for running,0.79 for swimming,0.80 for sitting,and 0.81 for sleeping,and was tested for real-time deployment with an inference time of 8.9 ms per image,being computationally light.Proposed YOLOv11’s improvements are attributed to architectural advancements like a more complex feature extraction process,better attention modules,and an anchor-free detection mechanism.While YOLOv10 was extremely stable in static activity recognition,YOLOv9 performed well in dynamic environments but suffered from overfitting,and YOLOv8,while being a decent baseline,failed to differentiate between overlapping static activities.The experimental results determine proposed YOLOv11 to be the most appropriate model,providing an ideal balance between accuracy,computational efficiency,and robustness for real-world deployment.Nevertheless,there exist certain issues to be addressed,particularly in discriminating against visually similar activities and the use of publicly available datasets.Future research will entail the inclusion of 3D data and multimodal sensor inputs,such as depth and motion information,for enhancing recognition accuracy and generalizability to challenging real-world environments. 展开更多
关键词 Human activity recognition YOLOv11 deep learning real-time detection anchor-free detection attention mechanisms object detection image classification multi-class recognition surveillance applications
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基于CAF-YOLO的煤矿井下打钻作业识别与工序判别
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作者 瞿雨馨 张富凯 +5 位作者 郭峰 蔡琛昂 李爱军 董璐 常文静 孙一菲 《工矿自动化》 北大核心 2026年第3期83-94,共12页
煤矿井下打钻场景具有光照不均、背景杂乱与强反光并存等成像退化特征,同时钻杆、钻尾等目标呈细长连续结构并伴随显著方向变化,在退钻/进钻过程中频繁发生遮挡与重叠,目标尺度跨度大、背景纹理干扰强,这使得仅依赖水平框的常规检测难... 煤矿井下打钻场景具有光照不均、背景杂乱与强反光并存等成像退化特征,同时钻杆、钻尾等目标呈细长连续结构并伴随显著方向变化,在退钻/进钻过程中频繁发生遮挡与重叠,目标尺度跨度大、背景纹理干扰强,这使得仅依赖水平框的常规检测难以满足工程需求。旋转框(OBB)检测具备更强的角度表征与长程依赖建模能力,使得目标定位、类别判别与框角度描述等结果更加准确。提出一种基于旋转目标检测模型(CAF-YOLO)的煤矿井下打钻作业识别与工序判别方法。CAF-YOLO在YOLOv13n-OBB的基础上进行改进:在骨干网络中引入RepLKNet大核结构模块,通过“大核卷积+小核卷积”的双路径协同建模增强长程上下文感知能力,提升钻杆、钻尾等细长结构目标在遮挡与复杂背景下的连续特征表达;在颈部网络中引入自适应特征融合模块,联合局部注意力与全局注意力生成融合权重,对跨层特征进行动态加权重组,抑制冗余背景响应并强化小目标及遮挡目标的判别特征;采用Focal Loss在分类分支对困难样本赋予更高权重,缓解正负样本与难易样本不均衡问题,从而提升模型在复杂井下工况下的检测鲁棒性与泛化能力。在此基础上,进一步构建面向打钻视频的时序状态判别方法,利用关键目标的空间位置、运动状态与人员接近信息进行视频级建模,实现打钻工序的准确判别。在自建UCMDO-OBB数据集上的实验结果表明,相较于YOLOv13n-OBB,CAF-YOLO的识别精确率提升了1.8%,召回率提升了4.3%,mAP@0.5提升了3.2%,m AP@0.5:0.95提升了3.3%,改进效果显著。在工序判别任务上,准确率达92.7%,宏平均F1分数达0.912,推进阶段平均绝对百分比误差为4.1%,能够有效实现视频级过程分析,为井下打钻作业的智能监测与安全管理提供技术支撑。 展开更多
关键词 打钻识别 YOLOv13n 旋转目标检测 旋转框 上下文增强 自适应特征融合 时序状态判别
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Fault Diagnosis for Aero-engine Applying a New Multi-class Support Vector Algorithm 被引量:4
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作者 徐启华 师军 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第3期175-182,共8页
Hierarchical Support Vector Machine (H-SVM) is faster in training and classification than other usual multi-class SVMs such as "1-V-R"and "1-V-1". In this paper, a new multi-class fault diagnosis algorithm based... Hierarchical Support Vector Machine (H-SVM) is faster in training and classification than other usual multi-class SVMs such as "1-V-R"and "1-V-1". In this paper, a new multi-class fault diagnosis algorithm based on H-SVM is proposed and applied to aero-engine. Before SVM training, the training data are first clustered according to their class-center Euclid distances in some feature spaces. The samples which have close distances are divided into the same sub-classes for training, and this makes the H-SVM have reasonable hierarchical construction and good generalization performance. Instead of the common C-SVM, the v-SVM is selected as the binary classifier, in which the parameter v varies only from 0 to 1 and can be determined more easily. The simulation results show that the designed H-SVMs can fast diagnose the multi-class single faults and combination faults for the gas path components of an aero-engine. The fault classifiers have good diagnosis accuracy and can keep robust even when the measurement inputs are disturbed by noises. 展开更多
关键词 support vector machine fault diagnosis multi-class classification
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Data fusion for fault diagnosis using multi-class Support Vector Machines 被引量:1
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作者 胡中辉 蔡云泽 +1 位作者 李远贵 许晓鸣 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第10期1030-1039,共10页
Multi-source multi-class classification methods based on multi-class Support Vector Machines and data fusion strategies are proposed in this paper. The centralized and distributed fusion schemes are applied to combine... Multi-source multi-class classification methods based on multi-class Support Vector Machines and data fusion strategies are proposed in this paper. The centralized and distributed fusion schemes are applied to combine information from several data sources. In the centralized scheme, all information from several data sources is centralized to construct an input space. Then a multi-class Support Vector Machine classifier is trained. In the distributed schemes, the individual data sources are proc-essed separately and modelled by using the multi-class Support Vector Machine. Then new data fusion strategies are proposed to combine the information from the individual multi-class Support Vector Machine models. Our proposed fusion strategies take into account that an Support Vector Machine (SVM) classifier achieves classification by finding the optimal classification hyperplane with maximal margin. The proposed methods are applied for fault diagnosis of a diesel engine. The experimental results showed that almost all the proposed approaches can largely improve the diagnostic accuracy. The robustness of diagnosis is also improved because of the implementation of data fusion strategies. The proposed methods can also be applied in other fields. 展开更多
关键词 Data fusion Fault diagnosis multi-class classification multi-class Support Vector Machines Diesel engine
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Wasserstein-1 Distance and Nonuniform Berry-Esseen Bound for a Supercritical Branching Process in a Random Environment
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作者 Hao WU Xiequan FAN +1 位作者 Zhiqiang GAO Yinna YE 《Journal of Mathematical Research with Applications》 CSCD 2023年第6期737-753,共17页
Let(Z_(n))_(n)≥0be a supercritical branching process in an independent and identically distributed random environment.We establish an optimal convergence rate in the Wasserstein-1 distance for the process(Z_(n))_(n)... Let(Z_(n))_(n)≥0be a supercritical branching process in an independent and identically distributed random environment.We establish an optimal convergence rate in the Wasserstein-1 distance for the process(Z_(n))_(n)≥0,which completes a result of Grama et al.[Stochastic Process.Appl.,2017,127(4):1255–1281].Moreover,an exponential nonuniform Berry-Esseen bound is also given.At last,some applications of the main results to the confidence interval estimation for the criticality parameter and the population size Znare discussed. 展开更多
关键词 Branching processes Random environment Wasserstein-1 distance Nonuniform Berry-Esseen bounds MR(2020)Subject classification 60J80 60K37 60F05 62E20
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基于YOLOv8的输电线路绝缘子表面缺陷识别算法 被引量:8
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作者 熊伟 路鑫 +1 位作者 邱维进 王平强 《电子测量技术》 北大核心 2025年第2期178-188,共11页
针对当前绝缘子表面缺陷识别存在的图像背景复杂、缺陷小目标识别效果差的问题,提出一种基于YOLOv8的输电线路绝缘子表面缺陷识别算法。首先,在主干网络引入CAF模块,增强模型对复杂图像场景的解析,增强全局和局部特征的提取能力;其次,... 针对当前绝缘子表面缺陷识别存在的图像背景复杂、缺陷小目标识别效果差的问题,提出一种基于YOLOv8的输电线路绝缘子表面缺陷识别算法。首先,在主干网络引入CAF模块,增强模型对复杂图像场景的解析,增强全局和局部特征的提取能力;其次,在模型的颈部网络增加GD机制,减少特征融合过程中信息的丢失,提升小目标检测能力;最后,采用ATFL分类损失函数,削弱复杂背景对小目标检测的干扰,引入PIOU边界框损失函数,提高识别精度,加快模型收敛速度。实验结果表明,该算法的mAP50达到94.1%,精确率达到92.5%,召回率达到91.3%,相较于基线模型分别提高了3.1%、0.7%、3.9%,且综合性能优于最近的YOLOv9s、YOLOv10s等代表性算法。 展开更多
关键词 目标检测 绝缘子表面缺陷识别 小目标 卷积和注意力融合 边界框损失函数 分类损失函数
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An improved random forest classifier for multi-class classification 被引量:16
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作者 Archana Chaudhary Savita Kolhe Raj Kamal 《Information Processing in Agriculture》 EI 2016年第4期215-222,共8页
The paper presents an improved-RFC(Random Forest Classifier)approach for multi-class disease classification problem.It consists of a combination of Random Forest machine learning algorithm,an attribute evaluator metho... The paper presents an improved-RFC(Random Forest Classifier)approach for multi-class disease classification problem.It consists of a combination of Random Forest machine learning algorithm,an attribute evaluator method and an instance filter method.It intends to improve the performance of Random Forest algorithm.The performance results confirm that the proposed improved-RFC approach performs better than Random Forest algorithm with increase in disease classification accuracy up to 97.80%for multi-class groundnut disease dataset.The performance of improved-RFC approach is tested for its efficiency on five benchmark datasets.It shows superior performance on all these datasets. 展开更多
关键词 Groundnut disease Improved-RFC Machine learning multi-class classification
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