Pub Date : 2018-05-18DOI: 10.1109/YAC.2018.8406400
Yulu Zhang, Liguo Shuai, Yali Ren, Huiling Chen
In recent years, deep convolutional networks have made a milestone progress in the field of image recognition. However, the recognition ability of the deep convolution network declines in the case of unbalanced training data, in terms of categories with fewer training images, the recognition ability of the deep convolution network declines more seriously. Aiming at this kind of problem, this paper presents a new classification method which recognizes a query image by comparing distances between category centers of CNN features of the whole training dataset and the corresponding CNN feature of this query image. The experimental results on Cifar-10 and Cifar-100 show that the claimed method can more accurately identify images whose categories have only a few training samples and that the mean precision of the recognition can be improved effectively.
{"title":"Image classification with category centers in class imbalance situation","authors":"Yulu Zhang, Liguo Shuai, Yali Ren, Huiling Chen","doi":"10.1109/YAC.2018.8406400","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406400","url":null,"abstract":"In recent years, deep convolutional networks have made a milestone progress in the field of image recognition. However, the recognition ability of the deep convolution network declines in the case of unbalanced training data, in terms of categories with fewer training images, the recognition ability of the deep convolution network declines more seriously. Aiming at this kind of problem, this paper presents a new classification method which recognizes a query image by comparing distances between category centers of CNN features of the whole training dataset and the corresponding CNN feature of this query image. The experimental results on Cifar-10 and Cifar-100 show that the claimed method can more accurately identify images whose categories have only a few training samples and that the mean precision of the recognition can be improved effectively.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121320591","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406387
Liang Xu, Yuping Lu, Zhen He, Ming Yin, Chenchen Song
The modeling and control problem of folding aircraft performing morphing-aided maneuver is studied in this paper. The relationship between the aircraft folding angle and the aerodynamic parameters is analyzed and modeled. The wing folding angle is viewed as an extra control input and the dynamic model of the morphing-aided maneuver is constructed. Considering the high nonlinearity and the hybrid disturbances of the system, a novel feedback linearization-based non-singular dynamic terminal sliding mode control (NDTSMC) approach is proposed. The convergence of the aircraft states within a finite time is proved to be guaranteed by NDTSMC, and chattering is eliminated by the integration of the switching control signals. Simulation results show that, the control precision and the robustness of the morphing aircraft are improved by NDTSMC, with a better chattering elimination. Higher maneuverability and disturbance rejection capability compared to conventional aircraft are also demonstrated by simulation.
{"title":"Sliding mode control of morphing-aided maneuver for folding aircraft","authors":"Liang Xu, Yuping Lu, Zhen He, Ming Yin, Chenchen Song","doi":"10.1109/YAC.2018.8406387","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406387","url":null,"abstract":"The modeling and control problem of folding aircraft performing morphing-aided maneuver is studied in this paper. The relationship between the aircraft folding angle and the aerodynamic parameters is analyzed and modeled. The wing folding angle is viewed as an extra control input and the dynamic model of the morphing-aided maneuver is constructed. Considering the high nonlinearity and the hybrid disturbances of the system, a novel feedback linearization-based non-singular dynamic terminal sliding mode control (NDTSMC) approach is proposed. The convergence of the aircraft states within a finite time is proved to be guaranteed by NDTSMC, and chattering is eliminated by the integration of the switching control signals. Simulation results show that, the control precision and the robustness of the morphing aircraft are improved by NDTSMC, with a better chattering elimination. Higher maneuverability and disturbance rejection capability compared to conventional aircraft are also demonstrated by simulation.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116354819","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 : 2018-05-18DOI: 10.1109/YAC.2018.8405798
Lingling Zhang, Ya Zhang
This paper studies the distributed sensor activation and target tracking problem for wireless sensor networks with limited sensing range. A novel approach based on a fully distributed event-triggered sensor activation strategy and a fully distributed Kalman filtering algorithm is proposed. The node's detection activation strategy is designed based on an event-triggered mechanism to autonomously determine whether to detect the target or not such that each node achieves better trade-offs between tracking error and energy saving. The consensus Kalman filtering algorithm is based on the minimum trace principal. It is proved that the proposed distributed Kalman filtering algorithm with the event-triggered sensor activation strategy has better composite performance than the full-triggered scheme. And a necessary and sufficient condition for the stability of the proposed distributed target tracking algorithm is also given. A simulation example is given to illustrate the theoretic results.
{"title":"A distributed energy-efficient target tracking algorithm based on event-triggered strategy for sensor networks","authors":"Lingling Zhang, Ya Zhang","doi":"10.1109/YAC.2018.8405798","DOIUrl":"https://doi.org/10.1109/YAC.2018.8405798","url":null,"abstract":"This paper studies the distributed sensor activation and target tracking problem for wireless sensor networks with limited sensing range. A novel approach based on a fully distributed event-triggered sensor activation strategy and a fully distributed Kalman filtering algorithm is proposed. The node's detection activation strategy is designed based on an event-triggered mechanism to autonomously determine whether to detect the target or not such that each node achieves better trade-offs between tracking error and energy saving. The consensus Kalman filtering algorithm is based on the minimum trace principal. It is proved that the proposed distributed Kalman filtering algorithm with the event-triggered sensor activation strategy has better composite performance than the full-triggered scheme. And a necessary and sufficient condition for the stability of the proposed distributed target tracking algorithm is also given. A simulation example is given to illustrate the theoretic results.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127478257","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406533
Kun Fan, Jun Yu Li, Si-Dian Li
The existing methods of robotic Chinese calligraphy either apply industrial programming techniques to teach a robot some specific characters on whole, or take brush-strokes as basic writing units to pursue agile calligraphy. However, the former is too stiff while the latter is difficult to reach a great similarity. To achieve both similarity and flexibility, we consider that finer grained control of robotic calligraphy is needed. Motivated by it, we present a new framework and method for controlling robotic calligraphy in fine granularity. It focuses on brushstroke primaries, more basic writing elements, approaching to the problem of low accuracy in local robotic writing. First, we study the effect of writing route, pressing depth and brush lag on brush footprints. Second, the writing route and the corresponding stroke information acquired from a character image are transformed into the writing actions of a robot. Finally, we conduct extensive experiments to validate the presented method and the results show that it can achieve satisfactory effect on robotic calligraphy.
{"title":"Fine grained control of robotic calligraphy","authors":"Kun Fan, Jun Yu Li, Si-Dian Li","doi":"10.1109/YAC.2018.8406533","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406533","url":null,"abstract":"The existing methods of robotic Chinese calligraphy either apply industrial programming techniques to teach a robot some specific characters on whole, or take brush-strokes as basic writing units to pursue agile calligraphy. However, the former is too stiff while the latter is difficult to reach a great similarity. To achieve both similarity and flexibility, we consider that finer grained control of robotic calligraphy is needed. Motivated by it, we present a new framework and method for controlling robotic calligraphy in fine granularity. It focuses on brushstroke primaries, more basic writing elements, approaching to the problem of low accuracy in local robotic writing. First, we study the effect of writing route, pressing depth and brush lag on brush footprints. Second, the writing route and the corresponding stroke information acquired from a character image are transformed into the writing actions of a robot. Finally, we conduct extensive experiments to validate the presented method and the results show that it can achieve satisfactory effect on robotic calligraphy.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133252981","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406348
Zhencai Wang, Hong Tian, Xinpeng Geng, Jiyao Cui, Tao Liu
Industrial processes with inverse response and time delay are difficult to control due to the presence of right half plant (RHP) zeros in the transfer functions. A predictor based two-degree-of-freedom (2DOF) control design is proposed in this paper for such processes of stable or integrating type. The proposed control system design is based on using a dead-time compensator (DTC) to predict the non-minimum phase (NMP) dynamics, such that a delay-free closed-loop control design could be established for performance optimization. By proposing the desired transfer functions for the set-point tracking and load disturbance rejection, respectively, the corresponding controllers are analytically derived in discrete-time domain for implementation in sampled systems. Illustrative examples from the literature are shown to demonstrate the superiority of the proposed control design.
{"title":"Predictor based 2DOF control design for inverse response processes with time delay","authors":"Zhencai Wang, Hong Tian, Xinpeng Geng, Jiyao Cui, Tao Liu","doi":"10.1109/YAC.2018.8406348","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406348","url":null,"abstract":"Industrial processes with inverse response and time delay are difficult to control due to the presence of right half plant (RHP) zeros in the transfer functions. A predictor based two-degree-of-freedom (2DOF) control design is proposed in this paper for such processes of stable or integrating type. The proposed control system design is based on using a dead-time compensator (DTC) to predict the non-minimum phase (NMP) dynamics, such that a delay-free closed-loop control design could be established for performance optimization. By proposing the desired transfer functions for the set-point tracking and load disturbance rejection, respectively, the corresponding controllers are analytically derived in discrete-time domain for implementation in sampled systems. Illustrative examples from the literature are shown to demonstrate the superiority of the proposed control design.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133363522","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}
In recent years, some experimental studies and simulations show that reinforcement learning (RL) is an effective learning control approach for solving certain quantum control problems. In this paper, Q-learning with different exploration strategies (e.g., ε-greedy and Softmax), probabilistic Q-learning (PQL) and quantum reinforcement learning (QRL) are applied to solve the state transition problem of two-level quantum systems (e.g., spin-1/2 systems), respectively. These reinforcement learning algorithms are introduced and analyzed regarding the learning control problem of the spin-1/2 system. According to the constraints of the control fields, two typical kinds of controllers, i.e., three-switch controller and Bang-Bang controller, are designed using reinforcement learning. The learning performance of the above RL algorithms for both of the three-switch control and Bang-Bang control of two-level quantum systems are demonstrated and analyzed.
{"title":"Control design of two-level quantum systems with reinforcement learning","authors":"Haixu Yu, Xudong Xu, Hailan Ma, Zhangqing Zhu, Chunlin Chen","doi":"10.1109/YAC.2018.8406503","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406503","url":null,"abstract":"In recent years, some experimental studies and simulations show that reinforcement learning (RL) is an effective learning control approach for solving certain quantum control problems. In this paper, Q-learning with different exploration strategies (e.g., ε-greedy and Softmax), probabilistic Q-learning (PQL) and quantum reinforcement learning (QRL) are applied to solve the state transition problem of two-level quantum systems (e.g., spin-1/2 systems), respectively. These reinforcement learning algorithms are introduced and analyzed regarding the learning control problem of the spin-1/2 system. According to the constraints of the control fields, two typical kinds of controllers, i.e., three-switch controller and Bang-Bang controller, are designed using reinforcement learning. The learning performance of the above RL algorithms for both of the three-switch control and Bang-Bang control of two-level quantum systems are demonstrated and analyzed.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133145671","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406464
Cheng Gao, Qihong Chen, Liyan Zhang, S. Quan
A new multi current loop control strategy for LCL grid connected inverter is proposed. Repetitive PI double loop strategy which uses the feedback form of grid side current, utilizes PI control to improve the dynamic performance of the system, Then, repetitive control outer loop is used to achieve the high-performance control of the grid current, suppress voltage fluctuation and nonlinear load effect on the grid current and track the baseband signal without static error control. And the capacitor current feedback LCL inverter system aims at suppressing the high frequency resonance of LCL output filter; Theoretical analysis and experimental results show that LCL type grid connected inverter with this method has the advantages of high accuracy, good dynamic performance and strong anti-interference ability.
{"title":"Current multi-loop control strategy for grid-connected inverter with LCL filter","authors":"Cheng Gao, Qihong Chen, Liyan Zhang, S. Quan","doi":"10.1109/YAC.2018.8406464","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406464","url":null,"abstract":"A new multi current loop control strategy for LCL grid connected inverter is proposed. Repetitive PI double loop strategy which uses the feedback form of grid side current, utilizes PI control to improve the dynamic performance of the system, Then, repetitive control outer loop is used to achieve the high-performance control of the grid current, suppress voltage fluctuation and nonlinear load effect on the grid current and track the baseband signal without static error control. And the capacitor current feedback LCL inverter system aims at suppressing the high frequency resonance of LCL output filter; Theoretical analysis and experimental results show that LCL type grid connected inverter with this method has the advantages of high accuracy, good dynamic performance and strong anti-interference ability.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124837586","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406485
Jiadong Li, Xueqi Li, Lijuan Yu
The ship AIS trajectory data is a record sequence of the ship's position and time. It contains a wealth of vessel navigation information, which helps to statistically analyze and predict ship traffic in a specific water area on a small time scale. At the same time, the ship AIS trajectory data is susceptible to noise and data loss in the process of collection, transmission, and analysis, resulting in a decrease in acquisition quality. In this regard, this paper determines whether the massive AIS data is abnormal and removes it, completes the noise reduction work, and uses the cubic spline interpolation to make the lost data be reconstructed. On the basis of obtaining clean data, a discriminant function is constructed to count the regularity of arrival of the ship on the observation surface, and then a time series method is used to model the ship traffic flow through the observation section at different time periods on a certain day. The simulation experiment confirms the rationality of the forecast result through comprehensive comparison with the RBF neural network model, and provides a reference for the maritime department to implement refined management.
{"title":"Ship traffic flow prediction based on AIS data mining","authors":"Jiadong Li, Xueqi Li, Lijuan Yu","doi":"10.1109/YAC.2018.8406485","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406485","url":null,"abstract":"The ship AIS trajectory data is a record sequence of the ship's position and time. It contains a wealth of vessel navigation information, which helps to statistically analyze and predict ship traffic in a specific water area on a small time scale. At the same time, the ship AIS trajectory data is susceptible to noise and data loss in the process of collection, transmission, and analysis, resulting in a decrease in acquisition quality. In this regard, this paper determines whether the massive AIS data is abnormal and removes it, completes the noise reduction work, and uses the cubic spline interpolation to make the lost data be reconstructed. On the basis of obtaining clean data, a discriminant function is constructed to count the regularity of arrival of the ship on the observation surface, and then a time series method is used to model the ship traffic flow through the observation section at different time periods on a certain day. The simulation experiment confirms the rationality of the forecast result through comprehensive comparison with the RBF neural network model, and provides a reference for the maritime department to implement refined management.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123309389","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406352
Qingsong Jiao, Jia Liu, Yunxi Zhang, Wenyu Lian
This paper mainly studies the problem of analysis and design of the PID controller for a quadrotor helicopter with six degrees of freedom. The position control, the attitude control of the PID controller parameters are adjusted, in order to make the final output value of the six degrees of freedom versus the expected value equality. In this way, the control purpose is achieved. Finally, it will go through simulations to test the validity of the conclusion.
{"title":"Analysis and design the controller for quadrotors based on PID control method","authors":"Qingsong Jiao, Jia Liu, Yunxi Zhang, Wenyu Lian","doi":"10.1109/YAC.2018.8406352","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406352","url":null,"abstract":"This paper mainly studies the problem of analysis and design of the PID controller for a quadrotor helicopter with six degrees of freedom. The position control, the attitude control of the PID controller parameters are adjusted, in order to make the final output value of the six degrees of freedom versus the expected value equality. In this way, the control purpose is achieved. Finally, it will go through simulations to test the validity of the conclusion.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121019323","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 : 2018-05-18DOI: 10.1109/YAC.2018.8406538
Jinbo Liu, Zhiyi Su, Jinlei Chen
Brushless DC machine (BLDCM) has found wide applications in many fields. How to brake electrically with regeneration capability for BLDCM is a new subject of great concern. This paper compares two emergent hybrid electric braking schemes recently. One is a “plugging+ regenerative” braking scheme, which blends plugging with regenerative braking method. The other is “dynamic+ regenerative” braking scheme, which combines dynamic braking with regenerative braking method. All of the problems involved in these two hybrid braking schemes such as switching laws of inverter, close-loop system implementation and their four-quadrant operation are investigated in detail. Effectiveness and validity of the proposed strategies are justified through simulation. Many important conclusions are drawn.
{"title":"Comparison of two electric braking methods with regenerative capability of brushless DC machine and their four-quadrant operation","authors":"Jinbo Liu, Zhiyi Su, Jinlei Chen","doi":"10.1109/YAC.2018.8406538","DOIUrl":"https://doi.org/10.1109/YAC.2018.8406538","url":null,"abstract":"Brushless DC machine (BLDCM) has found wide applications in many fields. How to brake electrically with regeneration capability for BLDCM is a new subject of great concern. This paper compares two emergent hybrid electric braking schemes recently. One is a “plugging+ regenerative” braking scheme, which blends plugging with regenerative braking method. The other is “dynamic+ regenerative” braking scheme, which combines dynamic braking with regenerative braking method. All of the problems involved in these two hybrid braking schemes such as switching laws of inverter, close-loop system implementation and their four-quadrant operation are investigated in detail. Effectiveness and validity of the proposed strategies are justified through simulation. Many important conclusions are drawn.","PeriodicalId":226586,"journal":{"name":"2018 33rd Youth Academic Annual Conference of Chinese Association of Automation (YAC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134415519","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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