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A New Solution for Feature Recognition from 2D Engineering Drawing
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作者 Liu Yunhua Gao Jun CAD Center of Huazhong University of Science & Technology,Wuhan 430074, China 《Computer Aided Drafting,Design and Manufacturing》 2001年第1期33-40,共8页
The paper presents a promised way of feature recognition from 2D engineering drawing——developing special system and extracting features from machining drawings. In general, researchers inclined to extract features f... The paper presents a promised way of feature recognition from 2D engineering drawing——developing special system and extracting features from machining drawings. In general, researchers inclined to extract features from design drawings and ignored machining drawings. Actually, both of machining and design information shows the same importance in developing new products. Not only can machining drawing provide us with feature model or 3D geometrical model of the part, but also they can be easily recognized. In the paper the processes and methods of feature recognition from three-cone-bit (A Kind of aiguilles used to drill oil well) machining drawings are introduced. Firstly, overall approach is explained. Secondly, two methods of form feature recognition are introduced: symbol-matching method used to analyze annularity or chained graph and method based on feature-hint used to recognize the general features. Thirdly, feature parameters are extracted. Finally, a practical implementation is given. 展开更多
关键词 feature recognition engineering drawing machining feature
全文增补中
Improved AAG based recognization of machining feature
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作者 顾琳 张广玉 +1 位作者 杨乐民 刘文剑 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期180-187,共8页
The lost information caused by feature interaction is restored by using auxiliary faces (AF) and virtual links (VL). The delta volume of the interacted features represented by concave attachable connected graph (CACG)... The lost information caused by feature interaction is restored by using auxiliary faces (AF) and virtual links (VL). The delta volume of the interacted features represented by concave attachable connected graph (CACG) can be decomposed into several isolated features represented by complete concave adjacency graph (CCAG). We can recognize the feature’s sketchy type by using CCAG as a hint; the exact type of the feature can be attained by deleting the auxiliary faces from the isolated feature. United machining feature (UMF) is used to represent the features that can be machined in the same machining process. It is important to the rationalizing of the process plans and reduce the time costing in machining. An example is given to demonstrate the effectiveness of this method. 展开更多
关键词 machining feature feature recognition feature interaction graph matching AUXILIARY face virtual link UNITED machining feature INTERMEDIATE information cell
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Accuracy comparison and improvement for state of health estimation of lithium-ion battery based on random partial recharges and feature engineering
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作者 Xingjun Li Dan Yu +1 位作者 Søren Byg Vilsen Daniel Ioan Stroe 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期591-604,共14页
State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging pro... State of health(SOH)estimation of e-mobilities operated in real and dynamic conditions is essential and challenging.Most of existing estimations are based on a fixed constant current charging and discharging aging profiles,which overlooked the fact that the charging and discharging profiles are random and not complete in real application.This work investigates the influence of feature engineering on the accuracy of different machine learning(ML)-based SOH estimations acting on different recharging sub-profiles where a realistic battery mission profile is considered.Fifteen features were extracted from the battery partial recharging profiles,considering different factors such as starting voltage values,charge amount,and charging sliding windows.Then,features were selected based on a feature selection pipeline consisting of filtering and supervised ML-based subset selection.Multiple linear regression(MLR),Gaussian process regression(GPR),and support vector regression(SVR)were applied to estimate SOH,and root mean square error(RMSE)was used to evaluate and compare the estimation performance.The results showed that the feature selection pipeline can improve SOH estimation accuracy by 55.05%,2.57%,and 2.82%for MLR,GPR and SVR respectively.It was demonstrated that the estimation based on partial charging profiles with lower starting voltage,large charge,and large sliding window size is more likely to achieve higher accuracy.This work hopes to give some insights into the supervised ML-based feature engineering acting on random partial recharges on SOH estimation performance and tries to fill the gap of effective SOH estimation between theoretical study and real dynamic application. 展开更多
关键词 feature engineering Dynamic forklift aging profile State of health comparison Machine learning Lithium-ion batteries
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Behavior Recognition of the Elderly in Indoor Environment Based on Feature Fusion of Wi-Fi Perception and Videos 被引量:1
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作者 Yuebin Song Chunling Fan 《Journal of Beijing Institute of Technology》 EI CAS 2023年第2期142-155,共14页
With the intensifying aging of the population,the phenomenon of the elderly living alone is also increasing.Therefore,using modern internet of things technology to monitor the daily behavior of the elderly in indoors ... With the intensifying aging of the population,the phenomenon of the elderly living alone is also increasing.Therefore,using modern internet of things technology to monitor the daily behavior of the elderly in indoors is a meaningful study.Video-based action recognition tasks are easily affected by object occlusion and weak ambient light,resulting in poor recognition performance.Therefore,this paper proposes an indoor human behavior recognition method based on wireless fidelity(Wi-Fi)perception and video feature fusion by utilizing the ability of Wi-Fi signals to carry environmental information during the propagation process.This paper uses the public WiFi-based activity recognition dataset(WIAR)containing Wi-Fi channel state information and essential action videos,and then extracts video feature vectors and Wi-Fi signal feature vectors in the datasets through the two-stream convolutional neural network and standard statistical algorithms,respectively.Then the two sets of feature vectors are fused,and finally,the action classification and recognition are performed by the support vector machine(SVM).The experiments in this paper contrast experiments between the two-stream network model and the methods in this paper under three different environments.And the accuracy of action recognition after adding Wi-Fi signal feature fusion is improved by 10%on average. 展开更多
关键词 human behavior recognition two-stream convolution neural network channel status information feature fusion support vector machine(SVM)
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Detection of Cocoa Leaf Diseases Using the CNN-Based Feature Extractor and XGBOOST Classifier
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作者 Kouassi Simeon Kouassi Mamadou Diarra +1 位作者 Kouassi Hilaire Edi Brou Jean-Claude Koua 《Open Journal of Applied Sciences》 2024年第10期2955-2972,共18页
Among all the plagues threatening cocoa cultivation in general, and particularly in West Africa, the swollen shoot viral disease is currently the most dangerous. The greatest challenge in the fight to eradicate this p... Among all the plagues threatening cocoa cultivation in general, and particularly in West Africa, the swollen shoot viral disease is currently the most dangerous. The greatest challenge in the fight to eradicate this pandemic remains its early detection. Traditional methods of swollen shoot detection are mostly based on visual observations, leading to late detection and/or diagnostic errors. The use of machine learning algorithms is now an alternative for effective plant disease detection. It is therefore crucial to provide efficient solutions to farmers’ cooperatives. In our study, we built a database of healthy and diseased cocoa leaves. We then explored the power of feature extractors based on convolutional neural networks such as VGG 19, Inception V3, DenseNet 201, and a custom CNN, combining their strengths with the XGBOOST classifier. The results of our experiments showed that this fusion of methods with XGBOOST yielded highly promising scores, outperforming the results of algorithms using the sigmoid function. These results were further consolidated by the use of evaluation metrics such as accuracy, mean squared error, F score, recall, and Matthews’s correlation coefficient. The proposed approach, combining state of the art feature extractors and the XGBOOST classifier, offers an efficient and reliable solution for the early detection of swollen shoot. Its implementation could significantly assist West African cocoa farmers in combating this devastating disease and preserving their crops. 展开更多
关键词 Machine Learning Cocoa Leaf Diseases Deep Learning Convolutional Neural Network feature Extraction Image recognition XGBOOST
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Vote-Based Feature Selection Method for Stratigraphic Recognition in Tunnelling Process of Shield Machine
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作者 Liman Yang Xuze Guo +5 位作者 Jianfu Chen Yixuan Wang Huaixiang Ma Yunhua Li Zhiguo Yang Yan Shi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第5期141-155,共15页
Shield machines are currently the main tool for underground tunnel construction. Due to the complexity and variability of the underground construction environment, it is necessary to accurately identify the ground in ... Shield machines are currently the main tool for underground tunnel construction. Due to the complexity and variability of the underground construction environment, it is necessary to accurately identify the ground in real-time during the tunnel construction process to match and adjust the tunnel parameters according to the geological conditions to ensure construction safety. Compared with the traditional method of stratum identifcation based on staged drilling sampling, the real-time stratum identifcation method based on construction data has the advantages of low cost and high precision. Due to the huge amount of sensor data of the ultra-large diameter mud-water balance shield machine, in order to balance the identifcation time and recognition accuracy of the formation, it is necessary to screen the multivariate data features collected by hundreds of sensors. In response to this problem, this paper proposes a voting-based feature extraction method (VFS), which integrates multiple feature extraction algorithms FSM, and the frequency of each feature in all feature extraction algorithms is the basis for voting. At the same time, in order to verify the wide applicability of the method, several commonly used classifcation models are used to train and test the obtained efective feature data, and the model accuracy and recognition time are used as evaluation indicators, and the classifcation with the best combination with VFS is obtained. The experimental results of shield machine data of 6 diferent geological structures show that the average accuracy of 13 features obtained by VFS combined with diferent classifcation algorithms is 91%;among them, the random forest model takes less time and has the highest recognition accuracy, reaching 93%, showing best compatibility with VFS. Therefore, the VFS algorithm proposed in this paper has high reliability and wide applicability for stratum identifcation in the process of tunnel construction, and can be matched with a variety of classifer algorithms. By combining 13 features selected from shield machine data features with random forest, the identifcation of the construction stratum environment of shield tunnels can be well realized, and further theoretical guidance for underground engineering construction can be provided. 展开更多
关键词 Shield machine Tunneling parameters feature selection Stratigraphic recognition
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An Effective Machine-Learning Based Feature Extraction/Recognition Model for Fetal Heart Defect Detection from 2D Ultrasonic Imageries
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作者 Bingzheng Wu Peizhong Liu +3 位作者 Huiling Wu Shunlan Liu Shaozheng He Guorong Lv 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1069-1089,共21页
Congenital heart defect,accounting for about 30%of congenital defects,is the most common one.Data shows that congenital heart defects have seriously affected the birth rate of healthy newborns.In Fetal andNeonatal Car... Congenital heart defect,accounting for about 30%of congenital defects,is the most common one.Data shows that congenital heart defects have seriously affected the birth rate of healthy newborns.In Fetal andNeonatal Cardiology,medical imaging technology(2D ultrasonic,MRI)has been proved to be helpful to detect congenital defects of the fetal heart and assists sonographers in prenatal diagnosis.It is a highly complex task to recognize 2D fetal heart ultrasonic standard plane(FHUSP)manually.Compared withmanual identification,automatic identification through artificial intelligence can save a lot of time,ensure the efficiency of diagnosis,and improve the accuracy of diagnosis.In this study,a feature extraction method based on texture features(Local Binary Pattern LBP and Histogram of Oriented Gradient HOG)and combined with Bag of Words(BOW)model is carried out,and then feature fusion is performed.Finally,it adopts Support VectorMachine(SVM)to realize automatic recognition and classification of FHUSP.The data includes 788 standard plane data sets and 448 normal and abnormal plane data sets.Compared with some other methods and the single method model,the classification accuracy of our model has been obviously improved,with the highest accuracy reaching 87.35%.Similarly,we also verify the performance of the model in normal and abnormal planes,and the average accuracy in classifying abnormal and normal planes is 84.92%.The experimental results show that thismethod can effectively classify and predict different FHUSP and can provide certain assistance for sonographers to diagnose fetal congenital heart disease. 展开更多
关键词 Congenital heart defect fetal heart ultrasonic standard plane image recognition and classification machine learning bag of words model feature fusion
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Novel feature fusion method for speech emotion recognition based on multiple kernel learning
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作者 金赟 宋鹏 +1 位作者 郑文明 赵力 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期129-133,共5页
In order to improve the performance of speech emotion recognition, a novel feature fusion method is proposed. Based on the global features, the local information of different kinds of features is utilized. Both the gl... In order to improve the performance of speech emotion recognition, a novel feature fusion method is proposed. Based on the global features, the local information of different kinds of features is utilized. Both the global and the local features are combined together. Moreover, the multiple kernel learning method is adopted. The global features and each kind of local feature are respectively associated with a kernel, and all these kernels are added together with different weights to obtain a mixed kernel for nonlinear mapping. In the reproducing kernel Hilbert space, different kinds of emotional features can be easily classified. In the experiments, the popular Berlin dataset is used, and the optimal parameters of the global and the local kernels are determined by cross-validation. After computing using multiple kernel learning, the weights of all the kernels are obtained, which shows that the formant and intensity features play a key role in speech emotion recognition. The classification results show that the recognition rate is 78. 74% by using the global kernel, and it is 81.10% by using the proposed method, which demonstrates the effectiveness of the proposed method. 展开更多
关键词 speech emotion recognition multiple kemellearning feature fusion support vector machine
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Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition 被引量:1
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作者 Yi-Chun Lai Shu-Yin Chiang +1 位作者 Yao-Chiang Kan Hsueh-Chun Lin 《Computers, Materials & Continua》 SCIE EI 2024年第6期3783-3803,共21页
Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation tracking.This study intr... Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation tracking.This study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in HAR.The analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the models.Additionally,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDM database,renowned for its challenging features,supports the framework’s resilience and adaptability.The ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVM),and random forest(RF),for data training.In contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature extraction.Furthermore,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model performance.The best accuracies of the ANFIS,SVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,respectively.Comparative analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVM,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,respectively.Finally,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research findings.In conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications. 展开更多
关键词 Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination
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Energy Theft Detection in Smart Grids with Genetic Algorithm-Based Feature Selection
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作者 Muhammad Umair Zafar Saeed +3 位作者 Faisal Saeed Hiba Ishtiaq Muhammad Zubair Hala Abdel Hameed 《Computers, Materials & Continua》 SCIE EI 2023年第3期5431-5446,共16页
As big data,its technologies,and application continue to advance,the Smart Grid(SG)has become one of the most successful pervasive and fixed computing platforms that efficiently uses a data-driven approach and employs... As big data,its technologies,and application continue to advance,the Smart Grid(SG)has become one of the most successful pervasive and fixed computing platforms that efficiently uses a data-driven approach and employs efficient information and communication technology(ICT)and cloud computing.As a result of the complicated architecture of cloud computing,the distinctive working of advanced metering infrastructures(AMI),and the use of sensitive data,it has become challenging tomake the SG secure.Faults of the SG are categorized into two main categories,Technical Losses(TLs)and Non-Technical Losses(NTLs).Hardware failure,communication issues,ohmic losses,and energy burnout during transmission and propagation of energy are TLs.NTL’s are human-induced errors for malicious purposes such as attacking sensitive data and electricity theft,along with tampering with AMI for bill reduction by fraudulent customers.This research proposes a data-driven methodology based on principles of computational intelligence as well as big data analysis to identify fraudulent customers based on their load profile.In our proposed methodology,a hybrid Genetic Algorithm and Support Vector Machine(GA-SVM)model has been used to extract the relevant subset of feature data from a large and unsupervised public smart grid project dataset in London,UK,for theft detection.A subset of 26 out of 71 features is obtained with a classification accuracy of 96.6%,compared to studies conducted on small and limited datasets. 展开更多
关键词 Big data data analysis feature engineering genetic algorithm machine learning
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Exact Recognition of Compound Features by Feature Adjacency Matrix Elimination Algorithm
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作者 Yu Yong Tang Rongxi (School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics, PRC)Xu Xi (Unmanned Air Vehicle Institute, Beijing University of Aeronautics and Astronautics, PRC) 《Computer Aided Drafting,Design and Manufacturing》 1998年第2期8-15,共8页
Aiming at the axiom of design for manufacture (DFM), this paper describes a recognition method for abstracting compound features from a part model and discloses the basic mechanism of compounding, also builds the cor... Aiming at the axiom of design for manufacture (DFM), this paper describes a recognition method for abstracting compound features from a part model and discloses the basic mechanism of compounding, also builds the corresponding 2D-simulation model. The inner association between feature neighboring and feature compounding is deeply discussed and, based on the essential transforming rule of two neighboring features, the corresponding feature adjacency matrix (FAM) of multi - feature entities are generated. For the manufacturing feature converted from the pure design feature; an innovative concept-homogenous compounding is presented to clarify the architecture of machining domain. Then, the FAM recurrence elimination algorithm is developed to determine all the compound features, and according to machining sequence, outputs a group of machining domains. 展开更多
关键词 feature recognition machining cell recognition feature modeling
全文增补中
A Minimal Subset of Features Using Feature Selection for Handwritten Digit Recognition
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作者 Areej Alsaafin Ashraf Elnagar 《Journal of Intelligent Learning Systems and Applications》 2017年第4期55-68,共14页
Many systems of handwritten digit recognition built using the complete set of features in order to enhance the accuracy. However, these systems lagged in terms of time and memory. These two issues are very critical is... Many systems of handwritten digit recognition built using the complete set of features in order to enhance the accuracy. However, these systems lagged in terms of time and memory. These two issues are very critical issues especially for real time applications. Therefore, using Feature Selection (FS) with suitable machine learning technique for digit recognition contributes to facilitate solving the issues of time and memory by minimizing the number of features used to train the model. This paper examines various FS methods with several classification techniques using MNIST dataset. In addition, models of different algorithms (i.e. linear, non-linear, ensemble, and deep learning) are implemented and compared in order to study their suitability for digit recognition. The objective of this study is to identify a subset of relevant features that provides at least the same accuracy as the complete set of features in addition to reducing the required time, computational complexity, and required storage for digit recognition. The experimental results proved that 60% of the complete set of features reduces the training time up to third of the required time using the complete set of features. Moreover, the classifiers trained using the proposed subset achieve the same accuracy as the classifiers trained using the complete set of features. 展开更多
关键词 DIGIT recognition REAL Time feature Selection MACHINE Learning Classification MNIST
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Hybrid Features for an Arabic Word Recognition System
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作者 Mehmmood A. Abd Sarab Al Rubeaai George Paschos 《Computer Technology and Application》 2012年第10期685-691,共7页
This research proposes and implements an Arabic Sub-Words Recognition System (ASWR). The system focuses on employing a combination of statistical and structural features to provide complete pattern's description an... This research proposes and implements an Arabic Sub-Words Recognition System (ASWR). The system focuses on employing a combination of statistical and structural features to provide complete pattern's description and enhances the recognition rate. Support Vector Machines (SVMs) is utilized as a promising pattern recognition tool. In addition to that, the problems of dots and holes are solved in a completely different way from the ones previously employed. The proposed system proceeds in several phases as follows: (1) image acquisition, (2) binarisation, (3) morphological processing, (4) feature extraction, which includes statistical features, i.e., moment invariants, and structural features, i.e., dot number, dot position, and number of holes, features, and (5) classification, using multi-class SVMs and applying a one-against-all technique. The proposed system has been tested using different sets of words and subwords and has achieved a nearly 98.90% recogiaition rate. Comparative results with NNs are also presented. 展开更多
关键词 Arabic word recognition support vector machines CLASSIFICATION feature extraction neural networks morphological.
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A SVM-Based Feature Extraction for Face Recognition
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作者 Peng Cui Tian-tian Yan 《国际计算机前沿大会会议论文集》 2016年第1期33-34,共2页
Social computing, a cross science of computational science and social science, is affecting people’s learning, work and life recently. Face recognition is going deep into every field of social life, and the feature e... Social computing, a cross science of computational science and social science, is affecting people’s learning, work and life recently. Face recognition is going deep into every field of social life, and the feature extraction is particularly important. Linear Discriminant Analysis (LDA) is an effective feature extraction method. However, the traditional LDA cannot solve the nonlinear problem and small sample problem existing in high dimensional space. In this paper, the method of the Support Vector-based Direct Discriminant Analysis (SVDDA) is proposed. It incorporates SVM algorithm into LDA, extends SVM to nonlinear eigenspace, and optimizes eigenvalue to improve performance. Moreover, this paper combines SVDDA with the social computing theory. The experiments were tested on different face datasets. Compared with other existing methods, SVDDA has higher robustness and optimal performance. 展开更多
关键词 DISCRIMINANT analysis FACE recognition Support VECTOR machine feature extraction
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Research on Feature Fusion Technology of Fruit and Vegetable Image Recognition Based on SVM
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作者 Yanqing Wang Yipu Wang +1 位作者 Chaoxia Shi Hui Shi 《国际计算机前沿大会会议论文集》 2016年第1期150-152,共3页
In order to improve the accuracy and stability of fruit and vegetable image recognition by single feature, this project proposed multi-feature fusion algorithms and SVM classification algorithms. This project not only... In order to improve the accuracy and stability of fruit and vegetable image recognition by single feature, this project proposed multi-feature fusion algorithms and SVM classification algorithms. This project not only introduces the Reproducing Kernel Hilbert space to improve the multi-feature compatibility and improve multi-feature fusion algorithm, but also introduces TPS transformation model in SVM classifier to improve the classification accuracy, real-time and robustness of integration feature. By using multi-feature fusion algorithms and SVM classification algorithms, experimental results show that we can recognize the common fruit and vegetable images efficiently and accurately. 展开更多
关键词 feature extraction Multi-feature FUSION Support VECTOR MACHINE FRUIT and VEGETABLE image recognition
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Feature Extraction of Stored-grain Insects Based on Ant Colony Optimization and Support Vector Machine Algorithm 被引量:1
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作者 胡玉霞 张红涛 +1 位作者 罗康 张恒源 《Agricultural Science & Technology》 CAS 2012年第2期457-459,共3页
[Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored... [Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored-grain insects. [Method] Through the analysis of feature extraction in the image recognition of the stored-grain insects, the recognition accuracy of the cross-validation training model in support vector machine (SVM) algorithm was taken as an important factor of the evaluation principle of feature extraction of stored-grain insects. The ant colony optimization (ACO) algorithm was applied to the automatic feature extraction of stored-grain insects. [Result] The algorithm extracted the optimal feature subspace of seven features from the 17 morphological features, including area and perimeter. The ninety image samples of the stored-grain insects were automatically recognized by the optimized SVM classifier, and the recognition accuracy was over 95%. [Conclusion] The experiment shows that the application of ant colony optimization to the feature extraction of grain insects is practical and feasible. 展开更多
关键词 Stored-grain insects Ant colony optimization algorithm Support vector machine feature extraction recognition
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REVERSE MODELING FOR CONIC BLENDING FEATURE
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作者 Fan Shuqian Ke Yinglin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期482-489,共8页
A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segme... A novel method to extract conic blending feature in reverse engineering is presented. Different from the methods to recover constant and variable radius blends from unorganized points, it contains not only novel segmentation and feature recognition techniques, but also bias corrected technique to capture more reliable distribution of feature parameters along the spine curve. The segmentation depending on point classification separates the points in the conic blend region from the input point cloud. The available feature parameters of the cross-sectional curves are extracted with the processes of slicing point clouds with planes, conic curve fitting, and parameters estimation and compensation, The extracted parameters and its distribution laws are refined according to statistic theory such as regression analysis and hypothesis test. The proposed method can accurately capture the original design intentions and conveniently guide the reverse modeling process. Application examples are presented to verify the high precision and stability of the proposed method. 展开更多
关键词 Computer-aided design Reverse engineering feature recognition Geometric modeling Statistic theory Blending surface
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基于Bag of Features的手势识别 被引量:4
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作者 陈小波 谢伙生 《计算机工程与设计》 CSCD 北大核心 2013年第3期983-988,共6页
基于视觉的手势识别中,手势的识别效果易受手势旋转,光照亮度的影响,针对该问题,借鉴了目标识别和图像检索领域的Bag of Features(特征袋)算法,将Bag of Features算法应用到手势识别领域。通过SURF(加速鲁棒性特征)算法提取手势图像的... 基于视觉的手势识别中,手势的识别效果易受手势旋转,光照亮度的影响,针对该问题,借鉴了目标识别和图像检索领域的Bag of Features(特征袋)算法,将Bag of Features算法应用到手势识别领域。通过SURF(加速鲁棒性特征)算法提取手势图像的特征描述符,使手势对尺度、旋转、光照具有很强的适应力,再应用Bag of Features算法把SURF特征描述符映射到一个统一维度的向量,即Bag of Features特征向量,再用支持向量机对图像得到的特征向量进行训练分类。实验结果表示,该方法不仅具有较高的时间效率,满足手势识别的实时性,而且即使在很大角度的旋转以及亮度的变化下,仍能达到较高的识别率。 展开更多
关键词 手势识别 特征袋 加速鲁棒性特征 向量量化 支持向量机
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Diesel Engine Valve Clearance Fault Diagnosis Based on Features Extraction Techniques and FastICA-SVM 被引量:9
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作者 Ya-Bing Jing Chang-Wen Liu +3 位作者 Feng-Rong Bi Xiao-Yang Bi Xia Wang Kang Shao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第4期991-1007,共17页
Numerous vibration-based techniques are rarely used in diesel engines fault diagnosis in a direct way, due to the surface vibration signals of diesel engines with the complex non-stationary and nonlinear time-varying ... Numerous vibration-based techniques are rarely used in diesel engines fault diagnosis in a direct way, due to the surface vibration signals of diesel engines with the complex non-stationary and nonlinear time-varying fea- tures. To investigate the fault diagnosis of diesel engines, fractal correlation dimension, wavelet energy and entropy as features reflecting the diesel engine fault fractal and energy characteristics are extracted from the decomposed signals through analyzing vibration acceleration signals derived from the cylinder head in seven different states of valve train. An intelligent fault detector FastICA-SVM is applied for diesel engine fault diagnosis and classification. The results demonstrate that FastlCA-SVM achieves higher classification accuracy and makes better general- ization performance in small samples recognition. Besides, the fractal correlation dimension and wavelet energy and entropy as the special features of diesel engine vibration signal are considered as input vectors of classifier FastlCA- SVM and could produce the excellent classification results. The proposed methodology improves the accuracy of fea- ture extraction and the fault diagnosis of diesel engines. 展开更多
关键词 feature extraction Diesel engine valve train FastlCA PCA Support vector machine
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A Survey on Artificial Intelligence in Posture Recognition 被引量:3
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作者 Xiaoyan Jiang Zuojin Hu +1 位作者 Shuihua Wang Yudong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期35-82,共48页
Over the years,the continuous development of new technology has promoted research in the field of posture recognition and also made the application field of posture recognition have been greatly expanded.The purpose o... Over the years,the continuous development of new technology has promoted research in the field of posture recognition and also made the application field of posture recognition have been greatly expanded.The purpose of this paper is to introduce the latest methods of posture recognition and review the various techniques and algorithms of posture recognition in recent years,such as scale-invariant feature transform,histogram of oriented gradients,support vectormachine(SVM),Gaussian mixturemodel,dynamic time warping,hiddenMarkovmodel(HMM),lightweight network,convolutional neural network(CNN).We also investigate improved methods of CNN,such as stacked hourglass networks,multi-stage pose estimation networks,convolutional posemachines,and high-resolution nets.The general process and datasets of posture recognition are analyzed and summarized,and several improved CNNmethods and threemain recognition techniques are compared.In addition,the applications of advanced neural networks in posture recognition,such as transfer learning,ensemble learning,graph neural networks,and explainable deep neural networks,are introduced.It was found that CNN has achieved great success in posture recognition and is favored by researchers.Still,a more in-depth research is needed in feature extraction,information fusion,and other aspects.Among classification methods,HMM and SVM are the most widely used,and lightweight network gradually attracts the attention of researchers.In addition,due to the lack of 3Dbenchmark data sets,data generation is a critical research direction. 展开更多
关键词 Posture recognition artificial intelligence machine learning deep neural network deep learning transfer learning feature extraction CLASSIFICATION
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