In the process of laminated veneer lumber, it requires manual adjustment of the position of the veneer to accurately position it, which is inaccurate and inefficient. Aiming at these problems, a veneer correction algorithm on machine vision is designed and applied to the production process of laminated veneer lumber. First, the veneer image is subjected to a preprocessing operation. Second, the canny operator is used to detect edges, and the Hough transform is used to detect veneer straight lines. Finally, the deviation angle and displacement deviation of the veneer are calculated. The experimental results show that the veneer image processing and the correction algorithm on machine vision perform well in measuring the deviation and adjusting the position of the board.
{"title":"Research on veneer correction system based on machine vision","authors":"Jianbo Sun, Nai-Jian Chen, Xiangdong Han, Xu Wang, Yulin Huang, Yingjun Li","doi":"10.1109/ICIEA.2019.8834160","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834160","url":null,"abstract":"In the process of laminated veneer lumber, it requires manual adjustment of the position of the veneer to accurately position it, which is inaccurate and inefficient. Aiming at these problems, a veneer correction algorithm on machine vision is designed and applied to the production process of laminated veneer lumber. First, the veneer image is subjected to a preprocessing operation. Second, the canny operator is used to detect edges, and the Hough transform is used to detect veneer straight lines. Finally, the deviation angle and displacement deviation of the veneer are calculated. The experimental results show that the veneer image processing and the correction algorithm on machine vision perform well in measuring the deviation and adjusting the position of the board.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129510488","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}
With the development of avionics system, the demand of health metrics of integrated system is getting stronger and stronger. By describing the requirements and resources of an integrated system logically, a requirementoriented health metrics method of integrated system is proposed in this paper, then a reconstruction model of system resources is proposed depend upon the method. Furthermore, the decision-making method based on health metrics of integrated system is discussed.
{"title":"Requirement-oriented health metrics of integrated avionics systems","authors":"Yangming Guo, Xiaodong Wang, Ningshe Zhao, Y. En, Jie-zhong Ma, Yun Huang","doi":"10.1109/ICIEA.2019.8931108","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8931108","url":null,"abstract":"With the development of avionics system, the demand of health metrics of integrated system is getting stronger and stronger. By describing the requirements and resources of an integrated system logically, a requirementoriented health metrics method of integrated system is proposed in this paper, then a reconstruction model of system resources is proposed depend upon the method. Furthermore, the decision-making method based on health metrics of integrated system is discussed.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129628458","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}
The traditional direct torque control (DTC) method for permanent magnet synchronous motor (PMSM) has the problems of unstable switching frequency, large torque ripple and high current harmonic distortion rate. To solve the above problems, this paper proposes direct torque control based on random zero vector space vector pulse width modulation (RZVSVPWM-DTC). Firstly, the mathematical model of PMSM is analyzed. It is found that the control current $i_{q}$ can directly control the torque. It is combined with the mathematical model of DTC, pointing out the shortcomings of the traditional DTC method. Secondly, the RZVSVPWM-DTC is analyzed to illustrate its advantages. Finally, the RZVSVPWM-DTC is used to replace the traditional DTC, and the torque and flux linkage are used as the control objects for simulation analysis. The simulation results show that the RZVSVPWM-DTC has a constant switching frequency, smaller torque ripple and lower line current distortion rate. The system has good dynamic and static performance, which verifies the feasibility and effectiveness of the method.
{"title":"Research on Direct Torque Control Based on RZVSVPWM of PMSM","authors":"Wenming Wu, F. Xie, Guoli Li, Kangkang Liang, Chenming Qiu, Hong-ling Jiang","doi":"10.1109/ICIEA.2019.8833809","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833809","url":null,"abstract":"The traditional direct torque control (DTC) method for permanent magnet synchronous motor (PMSM) has the problems of unstable switching frequency, large torque ripple and high current harmonic distortion rate. To solve the above problems, this paper proposes direct torque control based on random zero vector space vector pulse width modulation (RZVSVPWM-DTC). Firstly, the mathematical model of PMSM is analyzed. It is found that the control current $i_{q}$ can directly control the torque. It is combined with the mathematical model of DTC, pointing out the shortcomings of the traditional DTC method. Secondly, the RZVSVPWM-DTC is analyzed to illustrate its advantages. Finally, the RZVSVPWM-DTC is used to replace the traditional DTC, and the torque and flux linkage are used as the control objects for simulation analysis. The simulation results show that the RZVSVPWM-DTC has a constant switching frequency, smaller torque ripple and lower line current distortion rate. The system has good dynamic and static performance, which verifies the feasibility and effectiveness of the method.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128261969","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8833636
Chuqi Liu, Chenpeng Ji, Xiaoqiang Lin, Jian Yao, Hai Huang
The Doppler ultrasound fetal heart signals are weak and complex, while the background noise is strong. It results in many problems for household integrated Doppler fetal heart monitors, such as low sensitivity, small measuring area, low accuracy of fetal heart rates, and self-excited howling. A fetal heart signal processing algorithm is proposed in this paper, which includes the adaptive denoising method based on spectral subtraction and the non-linear self-excitation suppression processing algorithm. The measuring results in a Doppler ultrasound fetal heart simulator and pregnant women show that the good denoising effect can been achieved and the signal-to-noise of the signals can been greatly enhanced by the proposed algorithm. Also, the sensitivity of fetal heart measurement is improved and the self-excited howling is eliminated effectively.
{"title":"Study and Implementation of a Signal Processing Algorithm for Doppler Ultrasound Fetal Heart Signals","authors":"Chuqi Liu, Chenpeng Ji, Xiaoqiang Lin, Jian Yao, Hai Huang","doi":"10.1109/ICIEA.2019.8833636","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833636","url":null,"abstract":"The Doppler ultrasound fetal heart signals are weak and complex, while the background noise is strong. It results in many problems for household integrated Doppler fetal heart monitors, such as low sensitivity, small measuring area, low accuracy of fetal heart rates, and self-excited howling. A fetal heart signal processing algorithm is proposed in this paper, which includes the adaptive denoising method based on spectral subtraction and the non-linear self-excitation suppression processing algorithm. The measuring results in a Doppler ultrasound fetal heart simulator and pregnant women show that the good denoising effect can been achieved and the signal-to-noise of the signals can been greatly enhanced by the proposed algorithm. Also, the sensitivity of fetal heart measurement is improved and the self-excited howling is eliminated effectively.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128994537","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8833682
C. Lifen, Zhu Ke, S. Guoping
Power quality disturbance identification is vital for power quality study. However, noise, interference between disturbances and the effect of feature extraction method may lead to edge blurring of features extracted from different disturbances, thus affecting the accurate of disturbance recognition. Thence, the paper proposes a recognition method based on multi-domain feature fusion. Firstly, the neural network is trained preliminarily by mixed features of different domains, and then with the input characteristics of each domain, the action probability of hidden layer neurons in corresponding domain is determined according to the changes of cross-entropy before and after retention of the hidden layer neurons. Finally, work out the final results by the DS evidence theory, in which the independent evidence is transformed from identification results of unknown disturbances in different domains. The algorithm reduces the influence of errors in characteristics of a single domain on the identification accuracy, and is robust to noise and stable.
{"title":"Power quality disturbance identification method based on multi-domain feature fusion","authors":"C. Lifen, Zhu Ke, S. Guoping","doi":"10.1109/ICIEA.2019.8833682","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833682","url":null,"abstract":"Power quality disturbance identification is vital for power quality study. However, noise, interference between disturbances and the effect of feature extraction method may lead to edge blurring of features extracted from different disturbances, thus affecting the accurate of disturbance recognition. Thence, the paper proposes a recognition method based on multi-domain feature fusion. Firstly, the neural network is trained preliminarily by mixed features of different domains, and then with the input characteristics of each domain, the action probability of hidden layer neurons in corresponding domain is determined according to the changes of cross-entropy before and after retention of the hidden layer neurons. Finally, work out the final results by the DS evidence theory, in which the independent evidence is transformed from identification results of unknown disturbances in different domains. The algorithm reduces the influence of errors in characteristics of a single domain on the identification accuracy, and is robust to noise and stable.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124570370","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8833987
Tingting Yu, Yishuai Xu, Yifan Liu, P. Ouyang, M. Gupta, W.J. Zhang, W.J. Zhang
This paper reports a work on developing a novel charge control circuit for control of the piezoelectric actuator to overcome its hysteresis nonlinearity when the actuator is driven at high voltage (as opposed to low voltage reported in literature). The charge control circuit also includes a balancing resistor. A test-bed for a piezoelectric actuator was established and an experiment was conducted. The result showed that the hysteresis nonlinearity of the piezoelectric actuator was reduced by 82% under the proposed charge control circuit. This charge control circuit can be used for control of piezoelectric inertia-friction actuator, in which the piezoelectric actuator is part of the whole actuator system.
{"title":"A Novel Charge Control Circuit for Piezoelectric Actuators Driven by High Voltage","authors":"Tingting Yu, Yishuai Xu, Yifan Liu, P. Ouyang, M. Gupta, W.J. Zhang, W.J. Zhang","doi":"10.1109/ICIEA.2019.8833987","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833987","url":null,"abstract":"This paper reports a work on developing a novel charge control circuit for control of the piezoelectric actuator to overcome its hysteresis nonlinearity when the actuator is driven at high voltage (as opposed to low voltage reported in literature). The charge control circuit also includes a balancing resistor. A test-bed for a piezoelectric actuator was established and an experiment was conducted. The result showed that the hysteresis nonlinearity of the piezoelectric actuator was reduced by 82% under the proposed charge control circuit. This charge control circuit can be used for control of piezoelectric inertia-friction actuator, in which the piezoelectric actuator is part of the whole actuator system.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129796471","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8833992
Polash Kumar Das, F. Zhu, Shichao Chen, Can Luo, Prabhat Ranjan, Gang Xiong
With the advent of awareness toward quality of life by people has kindled a widespread investment and concern in science community for a better biomedical product and new technologies. Biomedical health is no longer limited to pharmaceutical drugs but monitoring of daily body vitals for prevention and improved diagnostics is getting a lot of attentions. In this paper, we are going to use wireless body area network technology (WBANT) for monitoring a patient's condition in a given system. With emerging practical use of WBANT, scientists have proposed many innovative ways for health and body vitals monitoring such as channel state information (CSI) and receiving signal strength indication (RSSI). CSI can characterize the multipath propagation of signal to some extent in comparison to RSSI method. So, we propose a system design for identification of narcolepsy disease combining wireless communication technology and computer science analytics. This system setup continuously transmits a particular frequency signal and the receiver obtains the reflected signal containing the patient's information in a given environment with changing body postures in real time. The various path gain data collected is used to extract and analyze characteristics of the patient position characterizing the disease of narcolepsy.
{"title":"Smart Medical Healthcare of Internet of Medical Things (IOMT): Application of Non-Contact Sensing","authors":"Polash Kumar Das, F. Zhu, Shichao Chen, Can Luo, Prabhat Ranjan, Gang Xiong","doi":"10.1109/ICIEA.2019.8833992","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833992","url":null,"abstract":"With the advent of awareness toward quality of life by people has kindled a widespread investment and concern in science community for a better biomedical product and new technologies. Biomedical health is no longer limited to pharmaceutical drugs but monitoring of daily body vitals for prevention and improved diagnostics is getting a lot of attentions. In this paper, we are going to use wireless body area network technology (WBANT) for monitoring a patient's condition in a given system. With emerging practical use of WBANT, scientists have proposed many innovative ways for health and body vitals monitoring such as channel state information (CSI) and receiving signal strength indication (RSSI). CSI can characterize the multipath propagation of signal to some extent in comparison to RSSI method. So, we propose a system design for identification of narcolepsy disease combining wireless communication technology and computer science analytics. This system setup continuously transmits a particular frequency signal and the receiver obtains the reflected signal containing the patient's information in a given environment with changing body postures in real time. The various path gain data collected is used to extract and analyze characteristics of the patient position characterizing the disease of narcolepsy.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129220915","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8834116
Henghua Shui, A. He, Jingnan Xu, Zhaoqing Hu, Liang Zhang
Study on soft black-start scheme for MMC-HVDC system with a large-scale wind farm is done in this paper. For a two-terminal MMC-HVDC system, when a fault occurs at one side, the converter station at the other side would be shut down. A three-stage startup strategy is especially given to realize the black start, which recoveries the DC voltage gradually, including uncontrollable and controllable charging process. For a three-terminal HVDC system, when a blackout situation occurs at the passive side with a wind farm, it would cause a DC voltage drop. To realize the black start, a controller is designed, which makes the AC side voltage of the converter stable enough to restart the wind farm without affecting the other converters. To validate it, simulations are built in PSCAD/EMTDC respectively. The result shows that there is a good effect for the black-start of the MMC-HVDC system by the proposed method.
{"title":"Study on Black-Start Scheme of MMC-HVDC System with a Large Scale Wind Farm","authors":"Henghua Shui, A. He, Jingnan Xu, Zhaoqing Hu, Liang Zhang","doi":"10.1109/ICIEA.2019.8834116","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834116","url":null,"abstract":"Study on soft black-start scheme for MMC-HVDC system with a large-scale wind farm is done in this paper. For a two-terminal MMC-HVDC system, when a fault occurs at one side, the converter station at the other side would be shut down. A three-stage startup strategy is especially given to realize the black start, which recoveries the DC voltage gradually, including uncontrollable and controllable charging process. For a three-terminal HVDC system, when a blackout situation occurs at the passive side with a wind farm, it would cause a DC voltage drop. To realize the black start, a controller is designed, which makes the AC side voltage of the converter stable enough to restart the wind farm without affecting the other converters. To validate it, simulations are built in PSCAD/EMTDC respectively. The result shows that there is a good effect for the black-start of the MMC-HVDC system by the proposed method.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123366931","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8834114
Li Sun, Wu Chen
Combining the centralized control with distributed control, a novel unified coordinated control strategy is proposed for a four-port DC microgrid. The centralized controller calculates energy storage and electric vehicle's charging current references based on microgrid power balance, while the distributed controller adds a current control link in the droop control to track the current reference given by the centralized controller. Hence, the converter can transmit any power within the allowable range of its capacity. With the proposed control strategy, the power transmitted between the converter and the DC bus can be quickly reduced to zero in the case of mode transition between operating modes, such as cutting off a converter or pitching in a converter, avoiding voltage shock and achieving seamless transition. Finally, the effectiveness of the proposed unified coordinated control strategy is verified by MATLAB simulation model.
{"title":"A Novel Control Strategy Based on Four-port DC Microgrid for Seamless Operating Modes Transition","authors":"Li Sun, Wu Chen","doi":"10.1109/ICIEA.2019.8834114","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834114","url":null,"abstract":"Combining the centralized control with distributed control, a novel unified coordinated control strategy is proposed for a four-port DC microgrid. The centralized controller calculates energy storage and electric vehicle's charging current references based on microgrid power balance, while the distributed controller adds a current control link in the droop control to track the current reference given by the centralized controller. Hence, the converter can transmit any power within the allowable range of its capacity. With the proposed control strategy, the power transmitted between the converter and the DC bus can be quickly reduced to zero in the case of mode transition between operating modes, such as cutting off a converter or pitching in a converter, avoiding voltage shock and achieving seamless transition. Finally, the effectiveness of the proposed unified coordinated control strategy is verified by MATLAB simulation model.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"198 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116372842","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 : 2019-06-01DOI: 10.1109/ICIEA.2019.8833687
Shuai Wang, Miao Zhu, Xu Zhong, X. Cai
The DC power flow controller can effectively enhance the control freedom and the stability in DC grid. In this paper, a three-terminal HVDC system is taken as an example to complete the network loss modeling with single DC power flow controller. Based on this model, the multiple DC power flow controllers have been used in the DC grid to reduce the network loss by adjusting their parameters properly. Compared with the traditional multi-terminal DC system without the DC power flow controller, the network loss can be significantly reduced.
{"title":"Effects of DC Power Flow Controller On DC Power Network Loss","authors":"Shuai Wang, Miao Zhu, Xu Zhong, X. Cai","doi":"10.1109/ICIEA.2019.8833687","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833687","url":null,"abstract":"The DC power flow controller can effectively enhance the control freedom and the stability in DC grid. In this paper, a three-terminal HVDC system is taken as an example to complete the network loss modeling with single DC power flow controller. Based on this model, the multiple DC power flow controllers have been used in the DC grid to reduce the network loss by adjusting their parameters properly. Compared with the traditional multi-terminal DC system without the DC power flow controller, the network loss can be significantly reduced.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121799841","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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