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The Investigation of Data Voting Algorithm for Train Air-Braking System Based on Multi-Classification SVM and ANFIS

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Chinese Journal of Electronics 2024年第1期33卷 274-281页

作者： Juhan WANG Ying GAO Yuan cao tao TANG School of Electronics and Information Engineering Beijing Jiaotong University Graduate Department China Academy of Railway Science National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University

The pressure data of the train air braking system is of great significance to accurately evaluate its operation state. In order to overcome the influence of sensor fault on the pressure data of train air braking system, it is necessary to design a set of sensor fault-tolerant voting mechanism to ensure that in the case of a pressure sensor fault, the system can accurately identify and locate the position of the faulty sensor, and estimate the fault data according to other normal data. A fault-tolerant mechanism based on multi-classification support vector machine(SVM) and adaptive network-based fuzzy inference system(ANFIS) is introduced. Multi-classification SVM is used to identify and locate the system fault state, and ANFIS is used to estimate the real data of the fault sensor. After estimation, the system will compare the real data of the fault sensor with the ANFIS estimated data. If it is similar,the system will recognize that there is a false alarm and record it. Then the paper tests the whole mechanism based on the real data. The test shows that the system can identify the fault samples and reduce the occurrence of false alarms.

关键词： Support vector machines Fault diagnosis Pressure sensors Fuzzy logic Fault tolerance Adaptive systems Fault tolerant systems

Dynamics of lubricated spiral bevel gears under different contact paths

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Friction 2022年第2期10卷 247-267页

作者： Wei cao tao HE Wei PU Ke XIAO School of Construction Machinery Chang'an University Xi'an 710064China Shantui Construction Machinery Co. Ltd.Jining 272073China Department of Mechanical Engineering Northwestern UniversityEvanstonIL60208USA School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China College of Mechanical Engineering Chongqing UniversityChongqing 400044.China

To assess the meshing quality of spiral bevel gears,the static meshing characteristics are usually checked under different contact paths to simulate the deviation in the footprint from the design point to the heel or toe of the gear flank caused by the assembly error of two gear ***,the effect of the contact path on gear dynamics under lubricated conditions has not been *** addition,most studies regarding spiral bevel gears disregard the lubricated condition because of the complicated solutions of mixed elastohydrodynamic lubrication(EHL).Hence,an analytical friction model with a highly efficient solution,whose friction coefficient and film thickness predictions agree well with the results from a well-validated mixed EHL model for spiral bevel gears,is established in the present study to facilitate the study of the dynamics of lubricated spiral bevel *** obtained results reveal the significant effect of the contact path on the dynamic response and meshing efficiency of gear ***,a comparison of the numerical transmission efficiency under different contact paths with experimental measurements indicates good agreement.

关键词： spiral bevel gears contact path dynamic response friction meshing efficiency

Stress response to nanoplastics with different charges in Brassica napus *** seed germination and seedling growth stages

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 41-52页

作者： tao Li Xiufeng cao Rui Zhao Zhaojie Cui School of Environmental Science and Engineering Shandong UniversityQingdao 266237China School of Municipal&Environmental Engineering Shandong Jianzhu UniversityJinan 250101China

Nanoplastic pollution has become a significant problem in farmland systems ***,research on the effects of nanoplastics(NPs)with different charges on field crops is still *** our study,NPs with different charges,including unmodified polystyrene nanoplastics(PS),positively charged polystyrene nanoplastics(PS-NH_(2)),and negatively charged polystyrene nanoplastics(PSSO3H),were investigated for their impacts on seed germination and seedling growth of *** results showed that seed water uptake(after 12 h),seed germination,seed vigour,and relative root elongation were all significantly reduced under exposure to NPs(200 mg/L).Similarly,remarkable decreases in plant biomass(root weight,shoot weight),growth(root length,plant height),photosynthesis ability(chlorophyll a,chlorophyll b,carotenoids),essential nutrient uptake(Fe,Mn,Zn,Cu),and plant quality(soluble protein,soluble sugar,crude fibre content)of rape seedlings were also observed after exposure to *** the three kinds of NPs,PS-NH_(2)showed stronger ***,superoxide dismutase,peroxidase,and catalase activities of rape seedlings were changed,and the content of malondialdehyde was significantly increased under exposure to ***,positively charged PS-NH_(2)showed stronger effects on the phenotype,physiology,biochemistry,nutrient uptake,and plant quality of ***,a comprehensive toxicity evaluation revealed that PS-NH_(2)had the strongest toxicity to *** present study provides important implications for the interaction and risk assessment of NPs and crops in soil-plant systems.

关键词： Nanoplastics Rape(Brassica napus L.) Physiology and biochemistry Nutrient absorption Plant quality Toxicity

Synthesis of unnatural N-glycosyl α-amino acids via Petasis reaction

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Chinese Chemical Letters 2014年第4期25卷 532-534页

作者： Chuan-Zhou tao Zhong-Tang Zhang jian-Wei Wu Rong-Hua Li Zhi-Ling cao School of Chemical Engineering Huaihai Institute of Technology jiangsu Marine Resources Development Research Institute

A convenient and efficient protocol for the synthesis of unnatural N-glycosyl cz-amino acids was developed. Condensation of 1,3,4,6-tetra-O-actyl-/%D-glucosamine hydrochloride, alkenyl boronic acid, and glyoxylic acid was achieved in CH2C12 to give the derivatives of 2-（N-glycosyl）aminobut-3-enoic acid which may find applications in glycobiology research and medicinal chemistry.

关键词： N-'Glycosyl s-amino acid Petasis reaction D-Glucosamine Alkenyl boronic acid

Effect of impact deformation on shape recovery behavior in Fe-Mn-Si shape memory alloy under shape memory training process with cyclic thermo-mechanical loading

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Science China(Technological Sciences) 2021年第7期64卷 1389-1400页

作者： SUN Qian cao Bo IWAMOTO Takeshi SUO tao Graduate School of Engineering Hiroshima UniversityHigashi-Hiroshima739-8527Japan Cluster of Excellence livMatS@FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies University of FreiburgFreiburgD-79110Germany Academy of Science and Technology Hiroshima UniversityHigashi-Hiroshima739-8527Japan School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China

In the past studies, it has been discovered that the shape memory effect(SME) in the Fe-Mn-Si shape memory alloy(Fe-SMA)can gradually be enhanced by a pre-process called as shape memory training process under cyclic thermo-mechanical *** the other hand, it has been shown that the SME of Fe-SMA can also be affected by changing the strain rate. Therefore, it is possible to improve the SME by combining the strain rate sensitivity and shape memory training process. However, the improvement of SME caused by the training process under impact condition is still unclear. For the training process under impact condition, it is difficult to interrupt the test at the desired strain level due to many reflections of stress waves, which reload the specimen from the free ends. In this paper, to obtain reliable experimental results of SME after the training process under impact condition, the stress waves after first loading are eliminated by the double momentum-trap structure introduced into the impact tensile testing apparatus based on the split Hopkinson pressure bar method. In order to achieve an optimum design of the structure used in experiments, the finite element simulation of the structure is performed. Then, tensile tests in the training process of Fe-28Mn-6Si-5Cr alloy at different strain rates including the impact level are conducted and temperature change of the specimen is measured during training and heating process. As a result, the improvement of SME in the alloy after the training process under quasi-static and impact loading is compared with that under quasi-static loading through verification processes.

关键词： Fe-Mn-Si shape memory alloy training cyclic thermo-mechanical process split Hopkinson pressure bar momentumtrap impact deformation

Research on High Precision Tracking Method of Guided Transport Vehicle Based on Autonomous Combination Positioning

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Chinese Journal of Electronics 2020年第4期29卷 779-785页

作者： cao Yuan ZHANG Shuangshuang YANG Guizhi WEN tao National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University School of Electronic and Information Engineering Beijing Jiaotong University

Guided transport vehicle(GTV) uses satellite positioning technology, lidar, and highperformance video sensors to achieve real-time positioning and tracing, these devices cost a *** addition, GTV shifts left and right during operation due to there is no fixed orbits *** is very important to detect the lateral offset in real time to ensure the accurate tracing of the vehicle along the dotted *** at the above issues, this paper proposes a low-cost high precision tracing method for GTV based on integrated positioning,high resolution estimation of the vehicles positioning information is implemented by Cubature Kalman filters(CKF) with a loosely coupled mode based on GPS/SINS in this method; Considering that GTV has a fixed driving route, a two-stage map matching algorithm based on Hidden Markov model(HMM) is proposed, which further improves the accuracy; The lateral offset distance is detected based on the positioning information, which provides theoretical support for the subsequent control of the precise operation of the *** algorithm’s feasibility has been verified by real vehicle experiments,the results show that the proposed algorithm achieves a centimeter-level positioning accuracy, and when the lateral offset distance is not less than 65 cm, the detection accuracy of the lateral offset distance is more than 92%.

关键词： Positioning and tracing CKF Map matching Lateral offset detection

3D-QSAR Studies on the Imidazopyrimidine Derivatives

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1985-1989页

作者： TONG jian-Bo cao Xu Shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and TechnologyXi'an 710021China

Comparative molecular field analysis(CoMFA) and comparative molecular similarity indices analysis(CoMSIA) for imidazopyrimidine derivatives were performed to get the molecular active conformation selection, molecular alignment, as well as the establishment of corresponding 3 D-QSAR model. The model established by this method has good ability to predict such compounds. For CoMFA model, the cross-validated q2 and non-cross-validated r2 values are 0.665 and 0.872, respectively. The best q2 value for CoMSIA model is 0.632 and r2 value is 0.923. Using this information and the three-dimensional equipotential map for molecular design can theoretically obtain some new antibacterial drugs with higher activity. There are two newly designed molecules with activity values of 7.921 and 7.872, which are higher than that of the template molecule No. 12 with an activity value of 7.850, and the QSAR research results can provide a theoretical reference for the synthesis of new drugs.

关键词： 3D-QSAR comparative molecular force field analysis molecular design

Identification of rural courtyards’utilization status using deep learning and machine learning methods on unmanned aerial vehicle images in north China

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Building Simulation 2024年第5期17卷 799-818页

作者： Maojun Wang Wenyu Xu Guangzhong cao tao Liu College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The issue of unoccupied or abandoned homesteads(courtyards)in China emerges given the increasing aging population,rapid urbanization and massive rural-urban *** the aspect of rural vitalization,land-use planning,and policy making,determining the number of unoccupied courtyards is *** and questionnaire-based surveys were currently the main approaches,but these traditional methods were often expensive and laborious.A new workflow is explored using deep learning and machine learning algorithms on unmanned aerial vehicle(UAV)***,features of the built environment were extracted using deep learning to evaluate the courtyard management,including extracting complete or collapsed farmhouses by Alexnet,detecting solar water heaters by YOLOv5s,calculating green looking ratio(GLR)by *** precisions exceeded 98%.Then,seven machine learning algorithms(Adaboost,binomial logistic regression,neural network,random forest,support vector machine,decision trees,and XGBoost algorithms)were applied to identify the rural courtyards’utilization *** Adaboost algorithm showed the best performance with the comprehensive consideration of most metrics(Accuracy:0.933,Precision:0.932,Recall:0.984,F1-score:0.957).Results showed that identifying the courtyards’utilization statuses based on the courtyard built environment is *** is transferable and cost-effective for large-scale village surveys,and may contribute to the intensive and sustainable approach to rural land use.

关键词： unoccupied homesteads courtyard built environment inner courtyard management GLR solar water heaters machine learning algorithms

Condition Monitoring for Railway Point Machines Based on Sound Analysis and Support Vector Machine

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Chinese Journal of Electronics 2020年第4期29卷 786-792页

作者： SUN Yongkui cao Yuan XIE Guo WEN tao School of Electronic and Information Engineering Beijing Jiaotong University National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi'an University of Technology

Railway point machines(RPMS) are one of the key equipments in the railway system to switch different routes for the *** monitoring for RPMs is a vital measure to keep train operation safe and *** convenience and low cost into consideration, a novel intelligent condition monitoring method for RPMs based on sound analysis is ***-domain and frequency-domain features are obtained,and normalized using z-score standardization method to eliminate the influences of different *** particle swarm optimization(BPSO) is utilized to select the most significant discrimination feature *** effects of the selected optimal features are verified using Support vector machine(SVM), 1-Nearest neighbor(1 NN), Random forest(RF), and Naive Bayes(NB).Experiment results indicate SVM performs best on identification accuracy and computing cost compared with the other three *** identification accuracies on normal switching and reverse switching processes reach100% and 99.67%, respectively, indicating the feasibility of the proposed method.

关键词： Condition monitoring Sound analysis Railway point machines(RPMs) Binary particle swarm optimization(BPSO) Support vector machine(SVM)