Pub Date : 2016-10-01DOI: 10.1109/IMCEC.2016.7867439
Cui Yuan, Xie Guanghan, Wang Huayang, Yan Yanju
The distributed power generation systems based on the renewable energy sources, such as solar photovoltaic, wind power, geothermal power, have been the focus of the world in the latest years. The grid-connected inverter is important power electronic implements, used to transfer the power from the DPGS to the public grid, and the quality of its output power has been studied a lot. The repetitive control technique based on the internal model principle, can achieve low steady-state tracking error and total harmonic distortion (THD) in AC systems, so it is widely adopted in the inverter systems. However in the practical applications, there are still some issues needs solving when using the repetitive control technique. To suppress the current distortion, a control strategy of fundamental current and harmonics controlled separately is adopted. On the synchronous rotating coordinate, the fundamental component is direct value and the harmonic component is alternating value. Proportion-integral (PI) values above which can achieved output controller and proportion resonant (PR) controller are adopted to control the power adjustment and zero error control of harmonic restrain.
{"title":"Harmonic current detection and suppression based on neural network","authors":"Cui Yuan, Xie Guanghan, Wang Huayang, Yan Yanju","doi":"10.1109/IMCEC.2016.7867439","DOIUrl":"https://doi.org/10.1109/IMCEC.2016.7867439","url":null,"abstract":"The distributed power generation systems based on the renewable energy sources, such as solar photovoltaic, wind power, geothermal power, have been the focus of the world in the latest years. The grid-connected inverter is important power electronic implements, used to transfer the power from the DPGS to the public grid, and the quality of its output power has been studied a lot. The repetitive control technique based on the internal model principle, can achieve low steady-state tracking error and total harmonic distortion (THD) in AC systems, so it is widely adopted in the inverter systems. However in the practical applications, there are still some issues needs solving when using the repetitive control technique. To suppress the current distortion, a control strategy of fundamental current and harmonics controlled separately is adopted. On the synchronous rotating coordinate, the fundamental component is direct value and the harmonic component is alternating value. Proportion-integral (PI) values above which can achieved output controller and proportion resonant (PR) controller are adopted to control the power adjustment and zero error control of harmonic restrain.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130526118","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7829156
Liang Yan, Lu Zhang, Zongxia Jiao, C. Gerada
This paper presents a rectangle direct-acting solenoid valve. The rectangle direct-acting solenoid valve have advantages of compact size, light weight, high reliability, fast response and high motion precision. Based on analytical method, this paper presents the eddy current calculation model of the moving-iron considering the skin effect. Then, the three-dimensional finite element modeling is established. And based on finite element method, the output force is calculated and analyzed. The analysis results provide a basis for the optimization design of the rectangle direct-acting solenoid valve.
{"title":"Design and modeling of a rectangular direct-acting solenoid valve","authors":"Liang Yan, Lu Zhang, Zongxia Jiao, C. Gerada","doi":"10.1109/CGNCC.2016.7829156","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829156","url":null,"abstract":"This paper presents a rectangle direct-acting solenoid valve. The rectangle direct-acting solenoid valve have advantages of compact size, light weight, high reliability, fast response and high motion precision. Based on analytical method, this paper presents the eddy current calculation model of the moving-iron considering the skin effect. Then, the three-dimensional finite element modeling is established. And based on finite element method, the output force is calculated and analyzed. The analysis results provide a basis for the optimization design of the rectangle direct-acting solenoid valve.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114643196","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7828802
Xin He, Leilei Li, Jiabin Chen, Zhongyu Zhang, Yansheng Dai
Polarization Navigation is a novel navigation method which learns from biology navigation mechanism. Because polarization navigation sensor's errors are not divergent, it can overcome the disadvantages of current navigation technologies. This paper presents a method to confirm the yaw angle of navigation system according to atmosphere polarization pattern. The current geographic position can be determined by the yaw angle and the relative distance information can provided by odometer. A novel polarization navigation sensor is designed by using division-of-amplitude method. Through measuring the stokes parameters of polarized light, the angle information can be gotten. According to the tests, the error of polarization sensor doesn't accumulate with time and the sensor can give the navigation information independently. In conclusion, it will play an important role in the automation navigation systems in the future.
{"title":"Research of polarization navigation system based on division-of-amplitude","authors":"Xin He, Leilei Li, Jiabin Chen, Zhongyu Zhang, Yansheng Dai","doi":"10.1109/CGNCC.2016.7828802","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828802","url":null,"abstract":"Polarization Navigation is a novel navigation method which learns from biology navigation mechanism. Because polarization navigation sensor's errors are not divergent, it can overcome the disadvantages of current navigation technologies. This paper presents a method to confirm the yaw angle of navigation system according to atmosphere polarization pattern. The current geographic position can be determined by the yaw angle and the relative distance information can provided by odometer. A novel polarization navigation sensor is designed by using division-of-amplitude method. Through measuring the stokes parameters of polarized light, the angle information can be gotten. According to the tests, the error of polarization sensor doesn't accumulate with time and the sensor can give the navigation information independently. In conclusion, it will play an important role in the automation navigation systems in the future.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116944760","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7829081
Y. Zhu, Haidong Shen, Yanbin Liu, G. Zhang, Yuping Lu
Considering strong coupling characteristics during flight, an integrated aero-propulsive/aero-elastic model of hypersonic vehicle is developed. The fuselage model is assumed as a free-free beam and finite element method is applied for flexible mode modeling. Then impact on the first three flexible modes of different bending stiffness are studied. Besides, frequency domain metrics: Bode integral and sensitivity bounds are analyzed under different bending stiffness. Finally, weighted H∞ suboptimal mixed sensitivity based controller is designed for the nonlinear flexible AHSV model. Simulation results show satisfactory response to the angle of attack tracking command and all states are asymptotically stable.
{"title":"Optimal control and analysis for aero-elastic model of hypersonic vehicle","authors":"Y. Zhu, Haidong Shen, Yanbin Liu, G. Zhang, Yuping Lu","doi":"10.1109/CGNCC.2016.7829081","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829081","url":null,"abstract":"Considering strong coupling characteristics during flight, an integrated aero-propulsive/aero-elastic model of hypersonic vehicle is developed. The fuselage model is assumed as a free-free beam and finite element method is applied for flexible mode modeling. Then impact on the first three flexible modes of different bending stiffness are studied. Besides, frequency domain metrics: Bode integral and sensitivity bounds are analyzed under different bending stiffness. Finally, weighted H∞ suboptimal mixed sensitivity based controller is designed for the nonlinear flexible AHSV model. Simulation results show satisfactory response to the angle of attack tracking command and all states are asymptotically stable.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127092925","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7828833
Hu Zhou, Haimeng Li, Guangping Qi, Wenting Li, Zongyou Xiang, Bo Lu
Common testability design method of simulated modeling, analysis and optimization for launch vehicle is introduced in this paper. The technical difficulties of testability design for launch vehicle are proposed firstly, subsequently the multi-signal model is adopted and the dependence matrix is established based on Warshall algorithm in order to analyze the testability specification for launch vehicle system. Then test plan is optimized by improved Genetic algorithm and two types of fitness functions. The feasibility of the method is proved by the results of testability design process for typical launch vehicle system.
{"title":"Design for testability analysis and test plan optimization for launch vehicle","authors":"Hu Zhou, Haimeng Li, Guangping Qi, Wenting Li, Zongyou Xiang, Bo Lu","doi":"10.1109/CGNCC.2016.7828833","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828833","url":null,"abstract":"Common testability design method of simulated modeling, analysis and optimization for launch vehicle is introduced in this paper. The technical difficulties of testability design for launch vehicle are proposed firstly, subsequently the multi-signal model is adopted and the dependence matrix is established based on Warshall algorithm in order to analyze the testability specification for launch vehicle system. Then test plan is optimized by improved Genetic algorithm and two types of fitness functions. The feasibility of the method is proved by the results of testability design process for typical launch vehicle system.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127139051","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7829176
Yuechen Huang, Haiyang Li
In the process of the high-speed vehicle sentering a rarefied atmosphere with highly uncertainties as the Mars atmosphere, the trajectory deviation caused by entry guidance can be the major part of the total landing errors. To reduce the impact of model errors on guidance performance, a guidance law based on receding horizon control is developed for reference trajectory tracking. At each guidance cycle, the prescribed trajectory as well as the commanded bank angle in finite horizon is obtained by an indirect optimization method based on Pontryagin's minimum principle. Then a set of algebraic and ordinary differential equations with their boundary conditions, called boundary value problem (BVP), are obtained. In this paper, the BVP is transformed into a system of nonlinear algebraic equations by using the differential transformation method to reduce the computational burden caused by differential operation. The system of algebraic equations is solved by a trust region Newton's method. Furthermore, the closed-loop guidance law is tested by the simulation of 500 entry cases with modeling errors and compared to the feedback linearization based guidance law. Numerical simulations show that the proposed guidance scheme is feasible and effective in tracking the nominal trajectory, thus has the potential to be applied to online guidance.
{"title":"Receding Horizon Optimal controller for reference trajectory tracking in Mars entry guidance","authors":"Yuechen Huang, Haiyang Li","doi":"10.1109/CGNCC.2016.7829176","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829176","url":null,"abstract":"In the process of the high-speed vehicle sentering a rarefied atmosphere with highly uncertainties as the Mars atmosphere, the trajectory deviation caused by entry guidance can be the major part of the total landing errors. To reduce the impact of model errors on guidance performance, a guidance law based on receding horizon control is developed for reference trajectory tracking. At each guidance cycle, the prescribed trajectory as well as the commanded bank angle in finite horizon is obtained by an indirect optimization method based on Pontryagin's minimum principle. Then a set of algebraic and ordinary differential equations with their boundary conditions, called boundary value problem (BVP), are obtained. In this paper, the BVP is transformed into a system of nonlinear algebraic equations by using the differential transformation method to reduce the computational burden caused by differential operation. The system of algebraic equations is solved by a trust region Newton's method. Furthermore, the closed-loop guidance law is tested by the simulation of 500 entry cases with modeling errors and compared to the feedback linearization based guidance law. Numerical simulations show that the proposed guidance scheme is feasible and effective in tracking the nominal trajectory, thus has the potential to be applied to online guidance.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127278693","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7828927
Yang Gao, Chenggang Bai
Nowadays graphical user interface (GUI) has been widely used in software systems, while there is no efficient testing techniques for the rapidly evolving GUI applications. For the GUI applications are modified rapidly and the test suites trend to be huge in size, it is often desirable to select a subset of test cases to fulfill the regression testing. In this paper, a novel GUI state model is presented to address the execution of test case, and then a state-coverage method based on cluster analysis of the GUI states is proposed to select a reliable subset of test cases for GUI regression testing. An empirical study illustrates that the state-coverage method is effective for GUI test case selection.
{"title":"Selecting test cases by cluster analysis of GUI states","authors":"Yang Gao, Chenggang Bai","doi":"10.1109/CGNCC.2016.7828927","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828927","url":null,"abstract":"Nowadays graphical user interface (GUI) has been widely used in software systems, while there is no efficient testing techniques for the rapidly evolving GUI applications. For the GUI applications are modified rapidly and the test suites trend to be huge in size, it is often desirable to select a subset of test cases to fulfill the regression testing. In this paper, a novel GUI state model is presented to address the execution of test case, and then a state-coverage method based on cluster analysis of the GUI states is proposed to select a reliable subset of test cases for GUI regression testing. An empirical study illustrates that the state-coverage method is effective for GUI test case selection.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127480345","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7829094
Chen Liu, Chaoyang Dong, Weilai Jiang
This paper proposed a novel finite-time adaptive terminal sliding mode controller for 6-DOF model of reentry RLV with external disturbance and parameters uncertainty. First, according to the multiple time scale features, the dynamics of attitude motion are divided into attitude angle subsystem and attitude angular rate subsystem. By estimating the upper bound of disturbance and uncertainty with an adaptive law, the controller for each subsystem can be designed. Also, the states of each subsystem can reach sliding surface in finite time is proved. The validity of this controller is illustrated by simulation.
{"title":"Finite-time adaptive terminal sliding mode controller design for reusable launch vehicle in reentry phase","authors":"Chen Liu, Chaoyang Dong, Weilai Jiang","doi":"10.1109/CGNCC.2016.7829094","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829094","url":null,"abstract":"This paper proposed a novel finite-time adaptive terminal sliding mode controller for 6-DOF model of reentry RLV with external disturbance and parameters uncertainty. First, according to the multiple time scale features, the dynamics of attitude motion are divided into attitude angle subsystem and attitude angular rate subsystem. By estimating the upper bound of disturbance and uncertainty with an adaptive law, the controller for each subsystem can be designed. Also, the states of each subsystem can reach sliding surface in finite time is proved. The validity of this controller is illustrated by simulation.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125007362","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7829108
B. Yan, Yunfeng Liu, Jingxin Dong
In silicon micro-machined resonant accelerometer, a drive and sense circuit based on ring diode is used, since the comb capacitance of the resonator is small and its working frequency is above 10 kHz. But there still exist some problems, such as serious delay and small detection sensitivity. To improve these problems, theoretical derivation and calculation of the sense circuit under static and dynamic situation are carried on, and a simulation circuit in Multisim is built by using the voltage-controlled capacitor instead of the comb capacitor after joining the drive circuit. According to the simulation results, the actual circuit parameters are optimized, which reduces the delay from 10 µs to 0.2 µs and improves the detection sensitivity to 41.3 V/pF. Finally the measurement noise of capacitance detection is below 0.5 aF/√Hz, equivalent to a displacement detection noise of 48 pm/√Hz. The improvement of signal-to-noise ratio allows a lower vibration amplitude of the resonator to obtain lower acceleration measurement noise.
{"title":"The optimization of drive and sense circuit in silicon micro-machined resonant accelerometer","authors":"B. Yan, Yunfeng Liu, Jingxin Dong","doi":"10.1109/CGNCC.2016.7829108","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829108","url":null,"abstract":"In silicon micro-machined resonant accelerometer, a drive and sense circuit based on ring diode is used, since the comb capacitance of the resonator is small and its working frequency is above 10 kHz. But there still exist some problems, such as serious delay and small detection sensitivity. To improve these problems, theoretical derivation and calculation of the sense circuit under static and dynamic situation are carried on, and a simulation circuit in Multisim is built by using the voltage-controlled capacitor instead of the comb capacitor after joining the drive circuit. According to the simulation results, the actual circuit parameters are optimized, which reduces the delay from 10 µs to 0.2 µs and improves the detection sensitivity to 41.3 V/pF. Finally the measurement noise of capacitance detection is below 0.5 aF/√Hz, equivalent to a displacement detection noise of 48 pm/√Hz. The improvement of signal-to-noise ratio allows a lower vibration amplitude of the resonator to obtain lower acceleration measurement noise.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125166918","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 : 2016-08-01DOI: 10.1109/CGNCC.2016.7828787
Guangde Xu, Zhongqiu Gou, Bainan Zhang
For the issue of attitude maneuver control of a large flexible spacecraft, a new control scheme of fast terminal sliding mode control based on path planning is proposed. The attitude dynamics state equation of a flexible spacecraft with single gimbal control moment gyros was established. To solve the problem that the attitude maneuver often leads to strong vibration of flexible appendages, the maneuvering path planning based on a curve of cosinusoidal angular acceleration change was given. Using the character that the fast sliding mode surface can converge to zero in finite time, a fast terminal sliding mode control strategy is designed based on the attitude error dynamics equation to tracking the planned maneuvering path. The simulation result shows the validity of the proposed method.
{"title":"Fast sliding mode control for attitude maneuver of a flexible spacecraft","authors":"Guangde Xu, Zhongqiu Gou, Bainan Zhang","doi":"10.1109/CGNCC.2016.7828787","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828787","url":null,"abstract":"For the issue of attitude maneuver control of a large flexible spacecraft, a new control scheme of fast terminal sliding mode control based on path planning is proposed. The attitude dynamics state equation of a flexible spacecraft with single gimbal control moment gyros was established. To solve the problem that the attitude maneuver often leads to strong vibration of flexible appendages, the maneuvering path planning based on a curve of cosinusoidal angular acceleration change was given. Using the character that the fast sliding mode surface can converge to zero in finite time, a fast terminal sliding mode control strategy is designed based on the attitude error dynamics equation to tracking the planned maneuvering path. The simulation result shows the validity of the proposed method.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125184272","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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