Pub Date : 2016-08-01DOI: 10.1109/CGNCC.2016.7828996
Jin-Yu Zeng, Xingong Cheng, X. Zong
With the widely application of a great quantity of nonlinear electrical components, harmonie and interharmonic components in power system have become a complicated problem. In the power system, there is fundamental wave, harmonics and interharmonics. The Fast Fourier Transform method can make the precise detection and analysis of integer harmonies come true, which based on simple transformation of FFT. In order to accurate detect interharmonics people must eliminate the interference between harmonie and fundamental. Their characteristic help us to distinguish them. In order to improve computing speed, three point method combine FFT Because of these improvement ,people can calculate interharmonics accuracy.
{"title":"A new interharmonics detection method based on spectrum leakage","authors":"Jin-Yu Zeng, Xingong Cheng, X. Zong","doi":"10.1109/CGNCC.2016.7828996","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828996","url":null,"abstract":"With the widely application of a great quantity of nonlinear electrical components, harmonie and interharmonic components in power system have become a complicated problem. In the power system, there is fundamental wave, harmonics and interharmonics. The Fast Fourier Transform method can make the precise detection and analysis of integer harmonies come true, which based on simple transformation of FFT. In order to accurate detect interharmonics people must eliminate the interference between harmonie and fundamental. Their characteristic help us to distinguish them. In order to improve computing speed, three point method combine FFT Because of these improvement ,people can calculate interharmonics accuracy.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"112 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":"124260839","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.2016.7828817
Bing Xu, L. Dou
This paper presents a vector tracking loop (VTL)-based carrier tracking algorithm assisted by desired trajectory of vehicles during short signal outages. The VTL-based carrier tracking algorithm is first derived. The desired trajectory of vehicles is then introduced to assist the VTL, ensuring that the carrier numerically controlled oscillator (NCO) keeps working during signal outages. The performance improvement of the proposed algorithm is verified in two different scenarios. It is shown that the VTL assisted by desired trajectory has higher frequency precision than that with no assistance. Besides, the proposed method can maintain the navigation solving and restrain the frequency error from increasing.
{"title":"Performance of the vector tracking loop assisted by desired trajectory during short signal outages","authors":"Bing Xu, L. Dou","doi":"10.1109/CGNCC.2016.7828817","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828817","url":null,"abstract":"This paper presents a vector tracking loop (VTL)-based carrier tracking algorithm assisted by desired trajectory of vehicles during short signal outages. The VTL-based carrier tracking algorithm is first derived. The desired trajectory of vehicles is then introduced to assist the VTL, ensuring that the carrier numerically controlled oscillator (NCO) keeps working during signal outages. The performance improvement of the proposed algorithm is verified in two different scenarios. It is shown that the VTL assisted by desired trajectory has higher frequency precision than that with no assistance. Besides, the proposed method can maintain the navigation solving and restrain the frequency error from increasing.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"5 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":"114795608","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.2016.7829002
Li He, Yunjie Wu, Zuo Jing-xing
For the attitude control of unmanned aerial vehicle(UAV), this paper proposes a kind of adaptive sliding mode controller based on backstepping. Backstepping control has the characteristics of simpleness in designing and convenience in application. Adding the backstepping method in the sliding mode controller can avoid the appearance of the signal function, simplify the controller and maximize the advantages of the two control methods. Interference estimator based on adaptive control realizes the estimation of interference compensation without establishing interference model and foreseeing the unknown upper bound of interference. The simulations' result shows that the novel approach has considerable steady and dynamic performances, as well as good robustness, which confirms the effectiveness of the proposed control method.
{"title":"Sliding mode controller design for UAV based on backstepping control","authors":"Li He, Yunjie Wu, Zuo Jing-xing","doi":"10.1109/CGNCC.2016.7829002","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829002","url":null,"abstract":"For the attitude control of unmanned aerial vehicle(UAV), this paper proposes a kind of adaptive sliding mode controller based on backstepping. Backstepping control has the characteristics of simpleness in designing and convenience in application. Adding the backstepping method in the sliding mode controller can avoid the appearance of the signal function, simplify the controller and maximize the advantages of the two control methods. Interference estimator based on adaptive control realizes the estimation of interference compensation without establishing interference model and foreseeing the unknown upper bound of interference. The simulations' result shows that the novel approach has considerable steady and dynamic performances, as well as good robustness, which confirms the effectiveness of the proposed control method.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"45 3 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":"114516507","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.2016.7828861
Nuan Wen, Zhenghua Liu, Le Chang, Yan Ren
This paper provides systematic analysis and design procedure for the time optimal control of a certain mini-submarine missile. Nowadays, horizontal launch with vertical separation proves to be one of the key technologies of the submarine-to-air missile. Control variable parameterization (CVP), as an optimal strategy, will be adopted to yield a prospective result. Particularly, to achieve fastest vertically, the essential problem remains to be a Bang-Bang control issue. Then the enhanced time-scaling transformation turns out to be an appropriate solution. Two controllers, that is, the proportional-derivative controller and the adopted CVP optimal controller are compared by conducting experiments in mathematical simulation.
{"title":"Time optimal control of mini-submarine missile based on control variable parameterization with enhanced time-scaling method","authors":"Nuan Wen, Zhenghua Liu, Le Chang, Yan Ren","doi":"10.1109/CGNCC.2016.7828861","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828861","url":null,"abstract":"This paper provides systematic analysis and design procedure for the time optimal control of a certain mini-submarine missile. Nowadays, horizontal launch with vertical separation proves to be one of the key technologies of the submarine-to-air missile. Control variable parameterization (CVP), as an optimal strategy, will be adopted to yield a prospective result. Particularly, to achieve fastest vertically, the essential problem remains to be a Bang-Bang control issue. Then the enhanced time-scaling transformation turns out to be an appropriate solution. Two controllers, that is, the proportional-derivative controller and the adopted CVP optimal controller are compared by conducting experiments in mathematical simulation.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"11 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":"114624684","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.2016.7829143
Liang Yan, Jingying Zhang, H. Duan, Zongxia Jiao
The improved particle swarm optimization (PSO) algorithm is used to optimize the structure of permanent magnetic spherical motor with four pairs of rotor poles. The objective is to maximize peak value of output torque and peak value of magnetic flux density. Seven variables are selected which are rotor radius, rotor core radius, the longitudinal angle and the latitudinal angle of single rotor pole, coil length, coil angle. Firstly, the magnetic field model and torque model of optimization is built. Based on the two models above, the objective function is deduced. Then the spherical motor is optimized based on the improved PSO algorithm. Finally, the optimization results indicate that the optimal structure parameters are obtained. In a word, Improved PSO algorithm shows great advantage in the optimal design of motor.
{"title":"Structure optimization of permanent magnet spherical motor utilizing improved Particle Swarm algorithm","authors":"Liang Yan, Jingying Zhang, H. Duan, Zongxia Jiao","doi":"10.1109/CGNCC.2016.7829143","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829143","url":null,"abstract":"The improved particle swarm optimization (PSO) algorithm is used to optimize the structure of permanent magnetic spherical motor with four pairs of rotor poles. The objective is to maximize peak value of output torque and peak value of magnetic flux density. Seven variables are selected which are rotor radius, rotor core radius, the longitudinal angle and the latitudinal angle of single rotor pole, coil length, coil angle. Firstly, the magnetic field model and torque model of optimization is built. Based on the two models above, the objective function is deduced. Then the spherical motor is optimized based on the improved PSO algorithm. Finally, the optimization results indicate that the optimal structure parameters are obtained. In a word, Improved PSO algorithm shows great advantage in the optimal design of motor.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"3 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":"114655288","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.2016.7829129
Hongwei Han, D. Qiao, Hongbo Chen
Taking advantage of the aerodynamic force to capture the vehicle from hyperbolic orbit to planetary orbit is a preferable approach because of the lower fuel consumption. This paper aims to research the Mars aerocapture process using the ballistic coefficient as control variable, and the inflatable deceleration device is used to change the ballistic coefficient. Firstly, the corridor is described in detail considering the different ballistic coefficients. Besides, the optimal aerocapture trajectories are analyzed, which show that they have bang-bang control structures. Additionally, the optimal results are showed under the different control structures, and the corresponding performances are presented. Finally, the optimal constant control problem is analyzed through the statistical results with the different initial conditions, and the change rules of the peak heating rate and the ballistic coefficient are given.
{"title":"Optimal ballistic coefficient control for Mars aerocapture","authors":"Hongwei Han, D. Qiao, Hongbo Chen","doi":"10.1109/CGNCC.2016.7829129","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829129","url":null,"abstract":"Taking advantage of the aerodynamic force to capture the vehicle from hyperbolic orbit to planetary orbit is a preferable approach because of the lower fuel consumption. This paper aims to research the Mars aerocapture process using the ballistic coefficient as control variable, and the inflatable deceleration device is used to change the ballistic coefficient. Firstly, the corridor is described in detail considering the different ballistic coefficients. Besides, the optimal aerocapture trajectories are analyzed, which show that they have bang-bang control structures. Additionally, the optimal results are showed under the different control structures, and the corresponding performances are presented. Finally, the optimal constant control problem is analyzed through the statistical results with the different initial conditions, and the change rules of the peak heating rate and the ballistic coefficient are given.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"102 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":"117300584","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.2016.7828814
Runyang Zou, Xueshi Ge, Geng Wang
Mobile robot is commonly used for firefighting, medical treatment, housekeeping, etc. The first trouble we should solve is navigation, and the most important part of mobile robot navigation is 3D reconstruction, which is also main part of this paper. In this paper, we compare several common RGB-D devices including Microsoft Kinect, Intel RealSense R200, Asus Xtion PRO Live. Then two main methods of 3D reconstruction in the indoor environment are introduced in the next chapter after comparison of devices. Variants of the ICP algorithm are followed at last.
移动机器人常用于消防、医疗、家政等。首先要解决的问题是导航，而移动机器人导航中最重要的部分是三维重建，这也是本文的主要内容。在本文中，我们比较了几种常见的RGB-D设备，包括微软Kinect，英特尔RealSense R200，华硕Xtion PRO Live。第二章通过对设备的比较，介绍了室内环境下两种主要的三维重建方法。最后对ICP算法进行了改进。
{"title":"Applications of RGB-D data for 3D reconstruction in the indoor environment","authors":"Runyang Zou, Xueshi Ge, Geng Wang","doi":"10.1109/CGNCC.2016.7828814","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828814","url":null,"abstract":"Mobile robot is commonly used for firefighting, medical treatment, housekeeping, etc. The first trouble we should solve is navigation, and the most important part of mobile robot navigation is 3D reconstruction, which is also main part of this paper. In this paper, we compare several common RGB-D devices including Microsoft Kinect, Intel RealSense R200, Asus Xtion PRO Live. Then two main methods of 3D reconstruction in the indoor environment are introduced in the next chapter after comparison of devices. Variants of the ICP algorithm are followed at last.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"5 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":"117332385","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.2016.7828876
Qing-yang Chen, Yue Li
To resolve the formation flight control problem for multiple UAVs (unmanned aerial vehicles), a method based on following of the guidance points is proposed in the paper. The method is realized with the leader-follower strategy. In the method, the guidance points for the leader vehicle are computed from the expected trajectory, while the points for the followers are obtained from the expected formation, and the guidance points of the leader vehicle. With the guidance points, a nonlinear guidance logic is adopted, to make the vehicles follow the expected trajectory. What's more, a desired speed controller is incorporated, to guarantee the performance of formation keeping, especially when turning. Simulations for different situations were carried out, to verify the performance of the proposed method.
{"title":"UAVs formation flight control based on following of the guidance points","authors":"Qing-yang Chen, Yue Li","doi":"10.1109/CGNCC.2016.7828876","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828876","url":null,"abstract":"To resolve the formation flight control problem for multiple UAVs (unmanned aerial vehicles), a method based on following of the guidance points is proposed in the paper. The method is realized with the leader-follower strategy. In the method, the guidance points for the leader vehicle are computed from the expected trajectory, while the points for the followers are obtained from the expected formation, and the guidance points of the leader vehicle. With the guidance points, a nonlinear guidance logic is adopted, to make the vehicles follow the expected trajectory. What's more, a desired speed controller is incorporated, to guarantee the performance of formation keeping, especially when turning. Simulations for different situations were carried out, to verify the performance of the proposed method.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"25 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":"116277733","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.2016.7828932
Ting Li, Yongping Yu, Jian Wang, R. Xie, Xinmin Wang
In this paper, a novel fault diagnosis method based on quantum particle swarm optimization (QPSO) and least square support vector regression (LSSVR) algorithm, was proposed to detect sensor faults for electro-hydraulic actuators. Prediction model based on LSSVR algorithm is established to forecast sensor output. By calculating the residual between the forecast output of the LSSVR model and the actual output of the sensor, a fault can be indicated. Furthermore, to improve the prediction accuracy of the LSSVR model, QPSO is employed to optimize the hyper-parameters used in the LSSVR model. Simulation experiments show that, compared with PSO-LSSVR, the prediction error of QPSO-LSSVR is smaller and the convergence rate is faster. The effectiveness of the fault diagnosis method for detecting several typical sensor faults, which occurred in the actuator system, is also verified in the simulation experiments.
{"title":"Sensor fault diagnosis for electro-hydraulic actuator based on QPSO-LSSVR","authors":"Ting Li, Yongping Yu, Jian Wang, R. Xie, Xinmin Wang","doi":"10.1109/CGNCC.2016.7828932","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7828932","url":null,"abstract":"In this paper, a novel fault diagnosis method based on quantum particle swarm optimization (QPSO) and least square support vector regression (LSSVR) algorithm, was proposed to detect sensor faults for electro-hydraulic actuators. Prediction model based on LSSVR algorithm is established to forecast sensor output. By calculating the residual between the forecast output of the LSSVR model and the actual output of the sensor, a fault can be indicated. Furthermore, to improve the prediction accuracy of the LSSVR model, QPSO is employed to optimize the hyper-parameters used in the LSSVR model. Simulation experiments show that, compared with PSO-LSSVR, the prediction error of QPSO-LSSVR is smaller and the convergence rate is faster. The effectiveness of the fault diagnosis method for detecting several typical sensor faults, which occurred in the actuator system, is also verified in the simulation experiments.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"136 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":"116290246","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.2016.7829113
Chuankai Liu, Xiaoxue Wang, Jia Wang, Jianhua Su, Baofeng Wang, G. Tang, Xiangyan Guo
Autonomous rendezvous and robotic capturing of flying targets is widely used in many space shuttle missions and it is very crucial for on-orbit service. To perform this task, tracking and pose estimation of the flying targets is usually considered as one of the most important issues, needing to be addressed among the whole process. Taking account of the specificity of space environment such as lighting and the continuity of the rendezvous process, in this paper, we design a fast tracking and accurate pose estimation algorithm for cooperative luminaries (or retro-reflectors), to guide a safe and reliable capturing operation. Different from available target tracking or searching method, this paper defines a new comparability measure function for target appearance and utilizes the continuity of target moving to limit the target search in a predicted range of the image, which accelerates the search process. Meanwhile, the projective shape changes of each luminary due to rotation are also considered to help improve the accuracy of the target extraction. With the positions of multiple target spots obtained from the image, least square method is applied to adjust the spatial pose results iteratively, and finally accurate pose estimation is achieved. Experiments on the simulated space target, which consists of six LEDs, validate the proposed method.
{"title":"Fast tracking and accurate pose estimation of space flying target based on monocular vision","authors":"Chuankai Liu, Xiaoxue Wang, Jia Wang, Jianhua Su, Baofeng Wang, G. Tang, Xiangyan Guo","doi":"10.1109/CGNCC.2016.7829113","DOIUrl":"https://doi.org/10.1109/CGNCC.2016.7829113","url":null,"abstract":"Autonomous rendezvous and robotic capturing of flying targets is widely used in many space shuttle missions and it is very crucial for on-orbit service. To perform this task, tracking and pose estimation of the flying targets is usually considered as one of the most important issues, needing to be addressed among the whole process. Taking account of the specificity of space environment such as lighting and the continuity of the rendezvous process, in this paper, we design a fast tracking and accurate pose estimation algorithm for cooperative luminaries (or retro-reflectors), to guide a safe and reliable capturing operation. Different from available target tracking or searching method, this paper defines a new comparability measure function for target appearance and utilizes the continuity of target moving to limit the target search in a predicted range of the image, which accelerates the search process. Meanwhile, the projective shape changes of each luminary due to rotation are also considered to help improve the accuracy of the target extraction. With the positions of multiple target spots obtained from the image, least square method is applied to adjust the spatial pose results iteratively, and finally accurate pose estimation is achieved. Experiments on the simulated space target, which consists of six LEDs, validate the proposed method.","PeriodicalId":426650,"journal":{"name":"2016 IEEE Chinese Guidance, Navigation and Control Conference (CGNCC)","volume":"21 4 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":"123509112","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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