Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9188899
Yanbing Guo, Lingjuan Miao, Xi Zhang
Since the raw pseudorange and pseudorange rate are taken as the measurements, the measurement equation of the tightly coupled SINS/GPS integrated navigation system is nonlinear. As a typical non-linear filtering algorithm, the Extended Kalman Filtering (EKF) linearizes the measurements and has high estimation accuracy in the tightly coupled SINS/GPS integrated navigation system. The state vector of the tightly coupled SINS/GPS integrated navigation system includes the states of two subsystems, therefore the dimension of the state vector is high. The dimension of the measurement vector depends on the number of received satellite signals. If many satellite signals are received, the dimension of the measurement vector is high. The high dimensions of the state vector and measurement vector will result in large computation load for the EKF. To solve this problem, this paper proposes an optimized filtering scheme based on the two-stage Kalman filtering and sequential Kalman filtering. In that case, the estimation accuracy is not seriously affected while the computation load is significantly reduced. The semi-physical simulation results prove the estimation accuracy of the proposed optimized filtering scheme.
{"title":"The Optimized Design of the Integrated Navigation Filter","authors":"Yanbing Guo, Lingjuan Miao, Xi Zhang","doi":"10.23919/CCC50068.2020.9188899","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9188899","url":null,"abstract":"Since the raw pseudorange and pseudorange rate are taken as the measurements, the measurement equation of the tightly coupled SINS/GPS integrated navigation system is nonlinear. As a typical non-linear filtering algorithm, the Extended Kalman Filtering (EKF) linearizes the measurements and has high estimation accuracy in the tightly coupled SINS/GPS integrated navigation system. The state vector of the tightly coupled SINS/GPS integrated navigation system includes the states of two subsystems, therefore the dimension of the state vector is high. The dimension of the measurement vector depends on the number of received satellite signals. If many satellite signals are received, the dimension of the measurement vector is high. The high dimensions of the state vector and measurement vector will result in large computation load for the EKF. To solve this problem, this paper proposes an optimized filtering scheme based on the two-stage Kalman filtering and sequential Kalman filtering. In that case, the estimation accuracy is not seriously affected while the computation load is significantly reduced. The semi-physical simulation results prove the estimation accuracy of the proposed optimized filtering scheme.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123061543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9189139
Haihong Chi, Xiangrui Gao
Multi-target detection for aerial video is widely applied for both military and civilian. A multi-target detection algorithm on aerial video with memory module is proposed in this paper. This method uses memory module to connect time-scale information, so that the information of past frames can be used to improve the detection result of the current frame. ShuffleNet unit which is based on depthwise convolution and channel mixing was been used in the feature extraction network. The experimental results on VisDrone dataset show that the detection algorithm presented in this paper possesses fast detection speed and higher accuracy.
{"title":"Aerial Video Multi-target Detection with Memory Module *","authors":"Haihong Chi, Xiangrui Gao","doi":"10.23919/CCC50068.2020.9189139","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9189139","url":null,"abstract":"Multi-target detection for aerial video is widely applied for both military and civilian. A multi-target detection algorithm on aerial video with memory module is proposed in this paper. This method uses memory module to connect time-scale information, so that the information of past frames can be used to improve the detection result of the current frame. ShuffleNet unit which is based on depthwise convolution and channel mixing was been used in the feature extraction network. The experimental results on VisDrone dataset show that the detection algorithm presented in this paper possesses fast detection speed and higher accuracy.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123124234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9188678
Zhijun Mu, Yuguang Wu, Hongxu Yin, Zhigang Liu, Chunxiu Liu
When a single-phase grounding fault occurs in the distribution network with DG (Distributed Generation), the fault location is mainly completed by the switch information at the node. This method cannot make full use of the fault information and cannot be applied to the intelligent distribution network under the background of massive data. To solve the above problems, a single-phase grounding fault location method based on MDS (Multidimensional Scaling) and DBSCAN (Density- Based Spatial Clustering of Applications with Noise) is proposed. The simulation results show that the proposed method is not affected by fault location, fault resistance, fault angle and line type, and the fault location results are accurate, which can effectively use the fault information.
{"title":"Study on Single-phase Ground Fault Location of Distribution Network Based on MDS and DBSCAN Clustering","authors":"Zhijun Mu, Yuguang Wu, Hongxu Yin, Zhigang Liu, Chunxiu Liu","doi":"10.23919/CCC50068.2020.9188678","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9188678","url":null,"abstract":"When a single-phase grounding fault occurs in the distribution network with DG (Distributed Generation), the fault location is mainly completed by the switch information at the node. This method cannot make full use of the fault information and cannot be applied to the intelligent distribution network under the background of massive data. To solve the above problems, a single-phase grounding fault location method based on MDS (Multidimensional Scaling) and DBSCAN (Density- Based Spatial Clustering of Applications with Noise) is proposed. The simulation results show that the proposed method is not affected by fault location, fault resistance, fault angle and line type, and the fault location results are accurate, which can effectively use the fault information.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116765692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9189351
Haiwen Wu, Dabo Xu, B. Jayawardhana
This paper considers robust output regulation of uncertain Euler-Lagrange (EL) systems by error (or relative position) and velocity feedback. We shall develop an adaptive internal model approach for the problem. Particularly, the proposed control law does not require apriori knowledge of reference signal and its derivatives, which are commonly assumed in literature. It enables a self-learning mechanism of the closed-loop EL systems where the adaptive internal model-based controller is able to learn the desired trajectories and adapt itself to the uncertain plant parameters. We also present a numerical example to illustrate the proposed result.
{"title":"Output regulation of Euler-Lagrange systems based on error and velocity feedback","authors":"Haiwen Wu, Dabo Xu, B. Jayawardhana","doi":"10.23919/CCC50068.2020.9189351","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9189351","url":null,"abstract":"This paper considers robust output regulation of uncertain Euler-Lagrange (EL) systems by error (or relative position) and velocity feedback. We shall develop an adaptive internal model approach for the problem. Particularly, the proposed control law does not require apriori knowledge of reference signal and its derivatives, which are commonly assumed in literature. It enables a self-learning mechanism of the closed-loop EL systems where the adaptive internal model-based controller is able to learn the desired trajectories and adapt itself to the uncertain plant parameters. We also present a numerical example to illustrate the proposed result.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121007078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9188782
Jiarui Su, Juntong Qi, Chong Wu, Mingming Wang, Jinjin Guo
Task assignment is the main conundrum of multiple unmanned aerial vehicles (multi-UAVs) cooperative task execution, which has great research value. To solve the problem of task scheduling for multi-UAVs, a method based on improved genetic algorithm is proposed in this paper. Firstly, a mathematical model of task assignment is established based on the application environment of multi-UAVs attacking targets. Secondly, aiming at the problem of slow convergence speed and easy to fall into local extremum of genetic algorithm, the improved Metropolis criterion of simulated annealing algorithm is introduced into the genetic algorithm. Finally, the simulation results show that the improved genetic algorithm can reduce the amount of calculation, improve the quality of the results, and solve the task assignment problem of multi-UAVs more effectively.
{"title":"Multi-UAVs Target Attack Based on Improved Genetic Algorithm","authors":"Jiarui Su, Juntong Qi, Chong Wu, Mingming Wang, Jinjin Guo","doi":"10.23919/CCC50068.2020.9188782","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9188782","url":null,"abstract":"Task assignment is the main conundrum of multiple unmanned aerial vehicles (multi-UAVs) cooperative task execution, which has great research value. To solve the problem of task scheduling for multi-UAVs, a method based on improved genetic algorithm is proposed in this paper. Firstly, a mathematical model of task assignment is established based on the application environment of multi-UAVs attacking targets. Secondly, aiming at the problem of slow convergence speed and easy to fall into local extremum of genetic algorithm, the improved Metropolis criterion of simulated annealing algorithm is introduced into the genetic algorithm. Finally, the simulation results show that the improved genetic algorithm can reduce the amount of calculation, improve the quality of the results, and solve the task assignment problem of multi-UAVs more effectively.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121134890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9188983
Tian Yuan, Quanjun Liu, Jin Guo
This paper investigates the identification of FIR (finite impulse response) systems with quantized input and binary-valued observations. First, we obtain the ML (maximum likelihood) function of the available data, and construct an estimation algorithm of the unknown parameters when solving the maximum likelihood solution by transforming it into the solution to a set of linear equations. Secondly, based on the weighted least squares optimization technique, we establish the corresponding estimation algorithms in the case that the unknown parameters respectively satisfy a priori equality constraint and inequality constraint. Then, the AIC criterion is designed for estimating the order of the system. Finally, a numerical simulation example is employed to verify the effectiveness of the theoretical results obtained.
{"title":"Identification of FIR Systems with Quantized Input and Binary-Valued Observations Under A Priori Parameter Constraint","authors":"Tian Yuan, Quanjun Liu, Jin Guo","doi":"10.23919/CCC50068.2020.9188983","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9188983","url":null,"abstract":"This paper investigates the identification of FIR (finite impulse response) systems with quantized input and binary-valued observations. First, we obtain the ML (maximum likelihood) function of the available data, and construct an estimation algorithm of the unknown parameters when solving the maximum likelihood solution by transforming it into the solution to a set of linear equations. Secondly, based on the weighted least squares optimization technique, we establish the corresponding estimation algorithms in the case that the unknown parameters respectively satisfy a priori equality constraint and inequality constraint. Then, the AIC criterion is designed for estimating the order of the system. Finally, a numerical simulation example is employed to verify the effectiveness of the theoretical results obtained.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127133938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9189088
Runfa Zhou, Zhicheng Li, Zaiyue Yang
This paper mainly focuses on the problem of optimal lane change between vehicle platoonings. In order to evaluate the influence of the speed fluctuation of the vehicle platooning system in different scenarios, a fluctuation evaluation index is designed with consideration of merging comfort. Further, a corresponding optimization algorithm is proposed to search the optimal lane change speed and distance when vehicles request to merging into platoon. Above analysis is important because changing lane at the optimal speed can suppress the disturbance caused by merging into platoon and improve the stability of the vehicle platooning system, which has potential benefits for improving the merging comfort, and reducing the fuel consumption of the entire platoon system. Simulation results show that the proposed optimization algorithm is effective to find the value of lane change factors corresponding to the minimum system speed fluctuation.
{"title":"Optimal Lane Change Analysis for Vehicle Platooning Based on Lateral and Longitudinal Control","authors":"Runfa Zhou, Zhicheng Li, Zaiyue Yang","doi":"10.23919/CCC50068.2020.9189088","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9189088","url":null,"abstract":"This paper mainly focuses on the problem of optimal lane change between vehicle platoonings. In order to evaluate the influence of the speed fluctuation of the vehicle platooning system in different scenarios, a fluctuation evaluation index is designed with consideration of merging comfort. Further, a corresponding optimization algorithm is proposed to search the optimal lane change speed and distance when vehicles request to merging into platoon. Above analysis is important because changing lane at the optimal speed can suppress the disturbance caused by merging into platoon and improve the stability of the vehicle platooning system, which has potential benefits for improving the merging comfort, and reducing the fuel consumption of the entire platoon system. Simulation results show that the proposed optimization algorithm is effective to find the value of lane change factors corresponding to the minimum system speed fluctuation.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127369011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9188484
Wang Jing, Hu Yunbing, Liu Ting-ting, Yang Xiujie
In order to monitor the water quality of rivers and lakes in real time in indoors, and protect the green hills and blue waters, a remote monitoring system of unattended surface water quality based on WSN (wireless sensor network) is designed and studied. The structure of the on-line monitoring system of water quality is studied, and the network and communication of the monitoring network are realized. Designs the pH monitoring sensor node, the intelligent wireless sensor network and the real-time information processing system are designed, and the information acquisition, processing, production, broadcasting and other functions of the whole system are finally completed. The experimental results show that the data transmitted by the method is accurate and reliable, can monitor the water quality of the river and lake basin in real time, and provide reference basis for the decision-making department, and provide real-time information for the good condition of the surface water quality.
{"title":"Research on the Sensor Node of the Unattended System for Remote Monitoring of the River and Lake","authors":"Wang Jing, Hu Yunbing, Liu Ting-ting, Yang Xiujie","doi":"10.23919/CCC50068.2020.9188484","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9188484","url":null,"abstract":"In order to monitor the water quality of rivers and lakes in real time in indoors, and protect the green hills and blue waters, a remote monitoring system of unattended surface water quality based on WSN (wireless sensor network) is designed and studied. The structure of the on-line monitoring system of water quality is studied, and the network and communication of the monitoring network are realized. Designs the pH monitoring sensor node, the intelligent wireless sensor network and the real-time information processing system are designed, and the information acquisition, processing, production, broadcasting and other functions of the whole system are finally completed. The experimental results show that the data transmitted by the method is accurate and reliable, can monitor the water quality of the river and lake basin in real time, and provide reference basis for the decision-making department, and provide real-time information for the good condition of the surface water quality.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127539245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9189110
Peng Wang, Yaowei Sun
In this paper, we study stability and L1-gain problems for switched positive systems, in which stability for any subsystems do not necessarily requirement. First, the sufficient condition for exponential stability is established. By exploiting the multiple linear co-positive Lyapunov function method, stabilization and L1-gain conditions of switched positive systems are proposed. To reduce the switching frequency, a mixed switching strategy is proposed, which is different from traditional state-dependent or time-dependent switching. Then, a set of state-feedback controllers and a mixed switching strategy are dual developed to stabilize the system, and the corresponding linear vector inequalities are examined in terms of linear programming. Furthermore, L1-gain is studied as well. Finally, a numerical example is provided to show the validity of the proposed techniques.
{"title":"Stability and L1-gain analysis for switched positive systems: a mixed switching strategy","authors":"Peng Wang, Yaowei Sun","doi":"10.23919/CCC50068.2020.9189110","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9189110","url":null,"abstract":"In this paper, we study stability and L1-gain problems for switched positive systems, in which stability for any subsystems do not necessarily requirement. First, the sufficient condition for exponential stability is established. By exploiting the multiple linear co-positive Lyapunov function method, stabilization and L1-gain conditions of switched positive systems are proposed. To reduce the switching frequency, a mixed switching strategy is proposed, which is different from traditional state-dependent or time-dependent switching. Then, a set of state-feedback controllers and a mixed switching strategy are dual developed to stabilize the system, and the corresponding linear vector inequalities are examined in terms of linear programming. Furthermore, L1-gain is studied as well. Finally, a numerical example is provided to show the validity of the proposed techniques.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124941533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.23919/CCC50068.2020.9189531
Z. Li, Yue-hong Dai, Jiejun Hu, Jun-yao Wang, Peng Tang
Based on joint-assisted exoskeleton technology, a concept of active spacesuit for future extraterrestrial exploration activities is presented. Firstly, we design the mechanical structure of joint-assisted exoskeleton of upper limb, and perform kinematic analysis on the upper limb to obtain the joint motion information when lifting load. We obtain the resistance torque of the spacesuit joint by the measuring equipment, and the total torque of the upper limb by the simplified two-links dynamic model. Then, we present the combination of adaptive impedance control and sliding mode control that based on CTC method. Finally, the prototype of joint-assisted exoskeleton robot of upper limb is fabricated and tested, and the experimental results indict that the control system can improve the trajectory tracking effect and eliminate the influences of environmental change. The research can not only help the astronauts more easily complete the task of collecting samples of the future manned space missions, but also provide a theoretical foundation for the subsequent research of active spacesuit.
{"title":"Design and Analysis of Joint-Assisted Exoskeleton Control System of Upper Limb in Active Spacesuit","authors":"Z. Li, Yue-hong Dai, Jiejun Hu, Jun-yao Wang, Peng Tang","doi":"10.23919/CCC50068.2020.9189531","DOIUrl":"https://doi.org/10.23919/CCC50068.2020.9189531","url":null,"abstract":"Based on joint-assisted exoskeleton technology, a concept of active spacesuit for future extraterrestrial exploration activities is presented. Firstly, we design the mechanical structure of joint-assisted exoskeleton of upper limb, and perform kinematic analysis on the upper limb to obtain the joint motion information when lifting load. We obtain the resistance torque of the spacesuit joint by the measuring equipment, and the total torque of the upper limb by the simplified two-links dynamic model. Then, we present the combination of adaptive impedance control and sliding mode control that based on CTC method. Finally, the prototype of joint-assisted exoskeleton robot of upper limb is fabricated and tested, and the experimental results indict that the control system can improve the trajectory tracking effect and eliminate the influences of environmental change. The research can not only help the astronauts more easily complete the task of collecting samples of the future manned space missions, but also provide a theoretical foundation for the subsequent research of active spacesuit.","PeriodicalId":255872,"journal":{"name":"2020 39th Chinese Control Conference (CCC)","volume":"47 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125882123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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