Pub Date : 2017-05-28DOI: 10.1109/CCDC.2017.7978980
Z. Mu, JinLing Qi, D. Ye, Keke Zhang
In the present paper the terminal orbital control in the satellite pursuit-evasion game was studied, where the orbital maneuver with using limited magnitude continuous thrust was involved for both the interceptor and target. Since considering the terminal application scenario the high nonlinear interception dynamics could be reduced to the CW equations. Based on the reduced CW equation, zero effort miss was proposed to obtain the orbit control strategy. And with adding the fuel consumption the controller was built. Finally, the proposed method was validated by the numerical simulation, and the advantage and weakness of the proposed control strategy was analyzed.
{"title":"Study on interception control strategies with zero effort miss","authors":"Z. Mu, JinLing Qi, D. Ye, Keke Zhang","doi":"10.1109/CCDC.2017.7978980","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978980","url":null,"abstract":"In the present paper the terminal orbital control in the satellite pursuit-evasion game was studied, where the orbital maneuver with using limited magnitude continuous thrust was involved for both the interceptor and target. Since considering the terminal application scenario the high nonlinear interception dynamics could be reduced to the CW equations. Based on the reduced CW equation, zero effort miss was proposed to obtain the orbit control strategy. And with adding the fuel consumption the controller was built. Finally, the proposed method was validated by the numerical simulation, and the advantage and weakness of the proposed control strategy was analyzed.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"71 1","pages":"2747-2754"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87980870","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7978060
C. Hou, Li-Sheng Hu
This article develops an adaptive control method for accommodating actuator faults in a class of unknown nonlinear systems without a priori knowledge of high-frequency gain. An adaptive high-gain K-filters with switching laws is proposed to suppress the nonlinearities which are dependent on the unmeasured states. Combining the Nussbaum-gain approach with backstepping design, an adaptive controller with high-gain function can be obtained. It is proved that the proposed control approach can guarantee that all the signals of the resulting closed-loop system are bounded and tracking error can be made as small as desired by appropriate choice of the design parameters. Simulation results are presented to show the effectiveness of the proposed scheme.
{"title":"Adaptive fault-tolerant output feedback control of uncertain nonlinear systems with unknown high-frequency gain sign","authors":"C. Hou, Li-Sheng Hu","doi":"10.1109/CCDC.2017.7978060","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978060","url":null,"abstract":"This article develops an adaptive control method for accommodating actuator faults in a class of unknown nonlinear systems without a priori knowledge of high-frequency gain. An adaptive high-gain K-filters with switching laws is proposed to suppress the nonlinearities which are dependent on the unmeasured states. Combining the Nussbaum-gain approach with backstepping design, an adaptive controller with high-gain function can be obtained. It is proved that the proposed control approach can guarantee that all the signals of the resulting closed-loop system are bounded and tracking error can be made as small as desired by appropriate choice of the design parameters. Simulation results are presented to show the effectiveness of the proposed scheme.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"69 1","pages":"23-27"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87746324","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7979170
Minyang Kang, Yang Liu, Yijing Zhao
For low altitude penetration task, unmanned aerial vehicles (UAVs) need to accomplish its task with collision free. However, due to the uncertainties in the flight environment, the application of UAV is undoubtedly affected in the actual complex flight environment. This paper presents a method based on Kalman filter to evaluate the risk of UAVs under the precondition of distance sensor noise, GPS sensor noise and model estimation noise, aiming to provide the security flight space. Meanwhile, experimental results verify the correctness of the algorithm.
{"title":"A threat modeling method based on Kalman filter for UAV path planning","authors":"Minyang Kang, Yang Liu, Yijing Zhao","doi":"10.1109/CCDC.2017.7979170","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7979170","url":null,"abstract":"For low altitude penetration task, unmanned aerial vehicles (UAVs) need to accomplish its task with collision free. However, due to the uncertainties in the flight environment, the application of UAV is undoubtedly affected in the actual complex flight environment. This paper presents a method based on Kalman filter to evaluate the risk of UAVs under the precondition of distance sensor noise, GPS sensor noise and model estimation noise, aiming to provide the security flight space. Meanwhile, experimental results verify the correctness of the algorithm.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"6 1","pages":"3823-3828"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79745556","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7978640
Yu Zhou
Failure trend analysis has to be based on observed operational failure data. Assume the failure data can be viewed as a series of data over time. And a set of time series will be obtained. So it is perfectly natural to use the time series model to test the failure trend. Then we consider the failure number arranged by time order as a variable. As a result of the effects of seasons and cycles, we found the structural time series model is the appropriate model for modeling the public transport vehicles failure data. The structural time series model used in this paper is added with four components, namely trend, cyclic, seasonal and irregular. The failure number forecasting and correcting are also be given. In order to illustrate the efficiency of the structural time series model, a real-world example will be presented.
{"title":"Failure trend analysis using time series model","authors":"Yu Zhou","doi":"10.1109/CCDC.2017.7978640","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978640","url":null,"abstract":"Failure trend analysis has to be based on observed operational failure data. Assume the failure data can be viewed as a series of data over time. And a set of time series will be obtained. So it is perfectly natural to use the time series model to test the failure trend. Then we consider the failure number arranged by time order as a variable. As a result of the effects of seasons and cycles, we found the structural time series model is the appropriate model for modeling the public transport vehicles failure data. The structural time series model used in this paper is added with four components, namely trend, cyclic, seasonal and irregular. The failure number forecasting and correcting are also be given. In order to illustrate the efficiency of the structural time series model, a real-world example will be presented.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"34 1","pages":"859-862"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81772715","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7979410
Xiwang Xia, Guowen Sun, Keke Zhang, Shufan Wu, Tian-Zhe Wang, Lei Xia, Shanwu Liu
From 2013 till the end of 2016, more than 552 NanoSats (500 CubeSats among them), weighing less than 10kg, have been launched successfully in total. With the explosive growth of NanoSats/CubeSats, Attitude Determination and Control System (ADCS) of NanoSats/CubeSats has undergone a profound transform and has changed from the initial passive attitude stabilization to active and precise attitude control. This paper summarizes the current state of the art in NanoSats/CubeSats technology for ADCS, based on an available data base of 377 sample ADCS systems from publically reported Nano/CubeSats missions. The advancement of NanoSat/CubeSat missions and their ADCS requirements are first summarized, a discussion on various ADCS sensors, attitude determination algorithms, actuators, and control schemes is then conducted. Further analyses on the various ADCS schemes versus their achievable performances are provided. This survey shows, NanoSat-compatible attitude actuators, miniaturized attitude sensors, GPS receivers and various attitude determination algorithms were widely adopted to achieve different pointing requirements. The reported attitude pointing accuracy has seen a range from being above 10 deg down to below 1 deg (according to different control schemes). Statistics indicates that almost every successfully launched NanoSat/CubeSat employs magnetometer, Sun sensors and magnetic coils; about 23% of the NanoSats/CubeSats had adopted passive attitude control strategies while more than 50% of them had adopted the advanced reaction wheels-based attitude control strategies, which would provide precise pointing.
{"title":"NanoSats/CubeSats ADCS survey","authors":"Xiwang Xia, Guowen Sun, Keke Zhang, Shufan Wu, Tian-Zhe Wang, Lei Xia, Shanwu Liu","doi":"10.1109/CCDC.2017.7979410","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7979410","url":null,"abstract":"From 2013 till the end of 2016, more than 552 NanoSats (500 CubeSats among them), weighing less than 10kg, have been launched successfully in total. With the explosive growth of NanoSats/CubeSats, Attitude Determination and Control System (ADCS) of NanoSats/CubeSats has undergone a profound transform and has changed from the initial passive attitude stabilization to active and precise attitude control. This paper summarizes the current state of the art in NanoSats/CubeSats technology for ADCS, based on an available data base of 377 sample ADCS systems from publically reported Nano/CubeSats missions. The advancement of NanoSat/CubeSat missions and their ADCS requirements are first summarized, a discussion on various ADCS sensors, attitude determination algorithms, actuators, and control schemes is then conducted. Further analyses on the various ADCS schemes versus their achievable performances are provided. This survey shows, NanoSat-compatible attitude actuators, miniaturized attitude sensors, GPS receivers and various attitude determination algorithms were widely adopted to achieve different pointing requirements. The reported attitude pointing accuracy has seen a range from being above 10 deg down to below 1 deg (according to different control schemes). Statistics indicates that almost every successfully launched NanoSat/CubeSat employs magnetometer, Sun sensors and magnetic coils; about 23% of the NanoSats/CubeSats had adopted passive attitude control strategies while more than 50% of them had adopted the advanced reaction wheels-based attitude control strategies, which would provide precise pointing.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"68 15","pages":"5151-5158"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91547459","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7978545
W. Bai, Feng Pan, Bo Yang Xing, Chao Pan, Meng Xin Pei
The fixed-point landing technology of multi-rotor aircraft is an indispensable step to realize fully autonomous flight. Most of the aircraft in the horizontal positioning relies on visual guidance, and PID control is generally used in height control, but it is difficult to resist the interference of the aircraft at low altitude spoiler. The Active Disturbance Rejection Controller(ADRC) designed in this paper can compensate the unknown disturbance independently of the exact model of the system, and effectively overcome the above problems. By detecting the target circle, the displacement vector from the center of the image to the center of the circle can be calculated, and then output the horizontal control amount to realize the horizontal alignment of the aircraft. Simultaneously, the landing height of the aircraft is controlled by using the auto-disturbance rejection controller. The experimental results show that the proposed algorithm can eliminate all kinds of spoiler disturbances at low altitude by feedforward compensation, and make the four — rotor aircraft landing in the target area quickly, steadily and accurately.
{"title":"Visual landing system of UAV based on ADRC","authors":"W. Bai, Feng Pan, Bo Yang Xing, Chao Pan, Meng Xin Pei","doi":"10.1109/CCDC.2017.7978545","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978545","url":null,"abstract":"The fixed-point landing technology of multi-rotor aircraft is an indispensable step to realize fully autonomous flight. Most of the aircraft in the horizontal positioning relies on visual guidance, and PID control is generally used in height control, but it is difficult to resist the interference of the aircraft at low altitude spoiler. The Active Disturbance Rejection Controller(ADRC) designed in this paper can compensate the unknown disturbance independently of the exact model of the system, and effectively overcome the above problems. By detecting the target circle, the displacement vector from the center of the image to the center of the circle can be calculated, and then output the horizontal control amount to realize the horizontal alignment of the aircraft. Simultaneously, the landing height of the aircraft is controlled by using the auto-disturbance rejection controller. The experimental results show that the proposed algorithm can eliminate all kinds of spoiler disturbances at low altitude by feedforward compensation, and make the four — rotor aircraft landing in the target area quickly, steadily and accurately.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"23 1","pages":"7509-7514"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84952278","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7979123
Mengjie Li, Dong Yin
In this paper, we present a fast segmentation algorithm based on the geometric characteristics of the objects and the attribute of medium. This algorithm is not only suitable for sparse point clouds, but also for dense point clouds. It is built up of three stages: First, the range image is established from the Velodyne VLP-16 laser scanner data, which changes the sparse characteristic of data in the original space and determines the close relationship between the data points. Then, according to the geometric relation of the adjacent data points and point clouds edges distribution analysis, a region growing method is used to complete the fast segmentation of point clouds data, obtaining a series of mutually disjoint subsets. Finally, based on the laser intensity, refined segmentation of the under-segmentation subset is addressed using the K-means clustering method. The point clouds of an indoor corridor scene are used to verify the superiority of our method and compared with three typical algorithms. Experimental results prove that our method can fastly and accurately segment objects in the scene, and is not sensitive to noise and satisfactory in anti-noise performance.
{"title":"A fast segmentation method of sparse point clouds","authors":"Mengjie Li, Dong Yin","doi":"10.1109/CCDC.2017.7979123","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7979123","url":null,"abstract":"In this paper, we present a fast segmentation algorithm based on the geometric characteristics of the objects and the attribute of medium. This algorithm is not only suitable for sparse point clouds, but also for dense point clouds. It is built up of three stages: First, the range image is established from the Velodyne VLP-16 laser scanner data, which changes the sparse characteristic of data in the original space and determines the close relationship between the data points. Then, according to the geometric relation of the adjacent data points and point clouds edges distribution analysis, a region growing method is used to complete the fast segmentation of point clouds data, obtaining a series of mutually disjoint subsets. Finally, based on the laser intensity, refined segmentation of the under-segmentation subset is addressed using the K-means clustering method. The point clouds of an indoor corridor scene are used to verify the superiority of our method and compared with three typical algorithms. Experimental results prove that our method can fastly and accurately segment objects in the scene, and is not sensitive to noise and satisfactory in anti-noise performance.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"22 1","pages":"3561-3565"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83188215","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7978315
Hanfeng Li, Xianfu Zhang, Xiandong Chen, Qingrong Liu
This paper is concerned with the problem of output feedback stabilization for a class of output-constrained nonlinear systems that are dominated by a lower triangular system. Firstly, an observer based output feedback control scheme is proposed using the dynamic gain control design approach. Then, based on the property of Barrier Lyapunov Functions and Lyapunov stability theory, the asymptotic stability of the closed-loop system is analyzed and the output constraint is not violated. Finally, an example is given to show that the proposed design procedure is very simple and efficient.
{"title":"Output feedback control for a class of output-constrained nonlinear systems","authors":"Hanfeng Li, Xianfu Zhang, Xiandong Chen, Qingrong Liu","doi":"10.1109/CCDC.2017.7978315","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978315","url":null,"abstract":"This paper is concerned with the problem of output feedback stabilization for a class of output-constrained nonlinear systems that are dominated by a lower triangular system. Firstly, an observer based output feedback control scheme is proposed using the dynamic gain control design approach. Then, based on the property of Barrier Lyapunov Functions and Lyapunov stability theory, the asymptotic stability of the closed-loop system is analyzed and the output constraint is not violated. Finally, an example is given to show that the proposed design procedure is very simple and efficient.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"20 1","pages":"6355-6359"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90714376","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7978076
Yi Wang, Yonghui Sun, Zhi-nong Wei, Guo-qiang Sun
Accurate state estimation is essential for the application of fractional order network system. In order to provide a more reliable state estimation method to address the inevitably data packet dropout problem of network control system, in this paper, a modified fractional order Kalman filter is developed by combining of the conventional fractional order Kalman filter and the proposed adaptive compensation approach. Simulation results are provided to demonstrate that the proposed method possesses much better estimation performances than the conventional fractional order Kalman filter.
{"title":"State estimation of fractional order network system based on modified fractional order Kalman filter","authors":"Yi Wang, Yonghui Sun, Zhi-nong Wei, Guo-qiang Sun","doi":"10.1109/CCDC.2017.7978076","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7978076","url":null,"abstract":"Accurate state estimation is essential for the application of fractional order network system. In order to provide a more reliable state estimation method to address the inevitably data packet dropout problem of network control system, in this paper, a modified fractional order Kalman filter is developed by combining of the conventional fractional order Kalman filter and the proposed adaptive compensation approach. Simulation results are provided to demonstrate that the proposed method possesses much better estimation performances than the conventional fractional order Kalman filter.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"2 1","pages":"112-116"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81430392","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 : 2017-05-28DOI: 10.1109/CCDC.2017.7979413
Han Cui, Wenjuan Peng, Tong Liu, Xiaohui Wei
In this paper the Cramer-Rao bound (CRB) for the estimation of nearfield source location under unknown gain/phase responses is analyzed. We first derive the CRB under the special case of single source and then extend to more general case of multiple sources. For single-source scenario we show that the CRB can be segmented into two parts, which separately corresponds to gain responses and phase responses. For multiple-sources scenario, we show that the CRB can be recursively calculated based on the single-source CRB expressions. The CRB expressions of multiple-sources scenario are in closed-form and only involve matrix multiplications. We show that with the increase in the number of incident sources, CRB increases.
{"title":"Cramér-rao bounds for multiple near field sources location under unknown gain/phase response","authors":"Han Cui, Wenjuan Peng, Tong Liu, Xiaohui Wei","doi":"10.1109/CCDC.2017.7979413","DOIUrl":"https://doi.org/10.1109/CCDC.2017.7979413","url":null,"abstract":"In this paper the Cramer-Rao bound (CRB) for the estimation of nearfield source location under unknown gain/phase responses is analyzed. We first derive the CRB under the special case of single source and then extend to more general case of multiple sources. For single-source scenario we show that the CRB can be segmented into two parts, which separately corresponds to gain responses and phase responses. For multiple-sources scenario, we show that the CRB can be recursively calculated based on the single-source CRB expressions. The CRB expressions of multiple-sources scenario are in closed-form and only involve matrix multiplications. We show that with the increase in the number of incident sources, CRB increases.","PeriodicalId":6588,"journal":{"name":"2017 29th Chinese Control And Decision Conference (CCDC)","volume":"48 1 1","pages":"5169-5173"},"PeriodicalIF":0.0,"publicationDate":"2017-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82789335","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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