Pub Date : 2019-06-01DOI: 10.1109/ICIEA.2019.8833990
Hongsheng Lu, B. Liu, Zheng Jiang, Huizhong Hu
An algorithm of reversed solving method for multipliers is proposed for solving quadratic programming problems of predictive controllers in this paper. Firstly, A Lagrange multiplier, transformed by the objective function and the variable constraints, is treated as the standard form of the quadratic programming (abbr. QP) of decision variables, and then a reversed solving method for multipliers is presented to obtain the approximate solution of the Lagrange multipliers which is used to obtain the solution of the control sequence. Compared with the conventional solving method for QP, the proposed method for multipliers can significantly improve the efficiency of solutions on the guarantee of solving accuracy. Secondly, the proposed algorithm is realized in the design of an vehicle trajectory tracking MPC controller, in which the decision variables of vehicle such as driving safety and comfort, are considered into the system model and they are as output constraints, and the physical limitation of the front-wheel corner is as an input constraint. Finally, the practicality of the proposed algorithm is verified by the vehicle trajectory tracking experiments.
{"title":"Constrained MPC Control Based on Reversed Solving Method for Multipliers and its Application","authors":"Hongsheng Lu, B. Liu, Zheng Jiang, Huizhong Hu","doi":"10.1109/ICIEA.2019.8833990","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833990","url":null,"abstract":"An algorithm of reversed solving method for multipliers is proposed for solving quadratic programming problems of predictive controllers in this paper. Firstly, A Lagrange multiplier, transformed by the objective function and the variable constraints, is treated as the standard form of the quadratic programming (abbr. QP) of decision variables, and then a reversed solving method for multipliers is presented to obtain the approximate solution of the Lagrange multipliers which is used to obtain the solution of the control sequence. Compared with the conventional solving method for QP, the proposed method for multipliers can significantly improve the efficiency of solutions on the guarantee of solving accuracy. Secondly, the proposed algorithm is realized in the design of an vehicle trajectory tracking MPC controller, in which the decision variables of vehicle such as driving safety and comfort, are considered into the system model and they are as output constraints, and the physical limitation of the front-wheel corner is as an input constraint. Finally, the practicality of the proposed algorithm is verified by the vehicle trajectory tracking experiments.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"76 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":"124678058","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.2019.8833706
Le Yuan, Zikun Cai, Tianchen Qiao, Xijun Yang
In order to improve the efficiency of the whole system, degrade the difficulty of device selection, and realize the on-board installation of magnetic components with reduced cost, high power single-phase active power factor corrector (APFC) has to adopt multi-channel interleaved bridged structure, and the switching frequency is set above 40kHz. The inductor current synthesis and fast recovery diode (FRD) current synthesis of single-phase APFC determine the current quality on the mains side and DC voltage quality on the output side, respectively. This paper focuses on investigation on the occurrence conditions of ripple zeros and ripple extremities of the synthesized inductor current. The aforesaid is theoretically analyzed and verified by means of simulation, which would lay a foundation for in-depth understanding and comprehensive grasp of the working principle of multi-channel interleaved single-phase APFC and play a guiding role in the design of PFC.
{"title":"Current Synthesis of Multi-channel Interleaved Single-phase APFC","authors":"Le Yuan, Zikun Cai, Tianchen Qiao, Xijun Yang","doi":"10.1109/ICIEA.2019.8833706","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833706","url":null,"abstract":"In order to improve the efficiency of the whole system, degrade the difficulty of device selection, and realize the on-board installation of magnetic components with reduced cost, high power single-phase active power factor corrector (APFC) has to adopt multi-channel interleaved bridged structure, and the switching frequency is set above 40kHz. The inductor current synthesis and fast recovery diode (FRD) current synthesis of single-phase APFC determine the current quality on the mains side and DC voltage quality on the output side, respectively. This paper focuses on investigation on the occurrence conditions of ripple zeros and ripple extremities of the synthesized inductor current. The aforesaid is theoretically analyzed and verified by means of simulation, which would lay a foundation for in-depth understanding and comprehensive grasp of the working principle of multi-channel interleaved single-phase APFC and play a guiding role in the design of PFC.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"8 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":"128525366","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.2019.8834100
Q. Xiao, Jianping Chen, Zhonghui Luo
The artificial cultivation of cordyceps militaris technology demand is high and the temperature, humidity, illumination intensity, illumination hours management and so on environment parameters have great influence on the yield and quality of cordyceps militaris. To achieve cordyceps militaris cultivation automation management, it is developed in this paper a set of automatic cultivation management system, this paper expounds the main composition and function of each part, especially the hardware and software of singlechip processor system and PC software design. The system has the merit of high degree of automation and intelligence to realize the remote monitoring, high efficiency, superior quality of cordyceps militaris's cultivation management.
{"title":"Design of Cordyceps Militaris Automatic Cultivation Management System","authors":"Q. Xiao, Jianping Chen, Zhonghui Luo","doi":"10.1109/ICIEA.2019.8834100","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834100","url":null,"abstract":"The artificial cultivation of cordyceps militaris technology demand is high and the temperature, humidity, illumination intensity, illumination hours management and so on environment parameters have great influence on the yield and quality of cordyceps militaris. To achieve cordyceps militaris cultivation automation management, it is developed in this paper a set of automatic cultivation management system, this paper expounds the main composition and function of each part, especially the hardware and software of singlechip processor system and PC software design. The system has the merit of high degree of automation and intelligence to realize the remote monitoring, high efficiency, superior quality of cordyceps militaris's cultivation management.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"480 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":"128289182","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.2019.8834280
Xiangyu Lv, Wei Hu, Yonghao Wang, Xiangyu Zhu
With the rapid development of computer and multimedia technology, the rational scheduling of multimedia tasks has long been the research topic for the efficient utilization of computer resources. We consider multimedia scheduling to be soft real-time scheduling. Real-time multimedia is very sensitive to latency and jitter, and the classic scheduling algorithm determines the execution time of a task based on the worst Execution time (WCET), which reduces CPU utilization. This paper presents a new low-latency multimedia hybrid scheduling algorithm based on time reservation. The performance of this new algorithm and classical multimedia algorithm is compared by experiments. The results show that the algorithm is not only low jitter but also can adapt to the randomness of multimedia task execution time compared with classical algorithm.
{"title":"A novel scheduling algorithm for multimedia tasks with low latency","authors":"Xiangyu Lv, Wei Hu, Yonghao Wang, Xiangyu Zhu","doi":"10.1109/ICIEA.2019.8834280","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834280","url":null,"abstract":"With the rapid development of computer and multimedia technology, the rational scheduling of multimedia tasks has long been the research topic for the efficient utilization of computer resources. We consider multimedia scheduling to be soft real-time scheduling. Real-time multimedia is very sensitive to latency and jitter, and the classic scheduling algorithm determines the execution time of a task based on the worst Execution time (WCET), which reduces CPU utilization. This paper presents a new low-latency multimedia hybrid scheduling algorithm based on time reservation. The performance of this new algorithm and classical multimedia algorithm is compared by experiments. The results show that the algorithm is not only low jitter but also can adapt to the randomness of multimedia task execution time compared with classical algorithm.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"46 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":"127063281","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.2019.8833982
Xiaoyu Han, Gang Yang, Shengli Qu, Ge Zhang, Minghong Chi
The weighted K-nearest neighbor (WKNN) is a main algorithm based on fingerprint for indoor localization. The weight is usually calculated by the inverse of the received signal strength indication (RSSI) distance between reference point and the test point, which does not take the exponential relationship between RSSI and physical distance into account. Some weighted algorithms (called physical distance algorithms), while considering their relationship, do not consider the physical distance of the reference point from the test point and the characteristics of the RSSI. Since the range of RSSIs received from different Bluetooth transmitting devices (Beacons) in the same area is different, the cosine similarity difference is extremely small, and the influence of the reference point on the positioning result cannot be fully expressed. Therefore, in order to improve the positioning accuracy, this paper proposes a method of normalizing RSSI and a new weighted algorithm based on the physical distance and on the cosine similarity of the processed RSSI. Experiments in the actual environment show that the proposed algorithm has better positioning accuracy, and the average positioning accuracy is 1.816m, which is 36.41% higher than NN, 14.54% higher than KNN, 12.27% higher than wKNN and 12.78% higher than the physical distance algorithm.
{"title":"A Weighted Algorithm Based on Physical Distance and Cosine Similarity for Indoor Localization","authors":"Xiaoyu Han, Gang Yang, Shengli Qu, Ge Zhang, Minghong Chi","doi":"10.1109/ICIEA.2019.8833982","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833982","url":null,"abstract":"The weighted K-nearest neighbor (WKNN) is a main algorithm based on fingerprint for indoor localization. The weight is usually calculated by the inverse of the received signal strength indication (RSSI) distance between reference point and the test point, which does not take the exponential relationship between RSSI and physical distance into account. Some weighted algorithms (called physical distance algorithms), while considering their relationship, do not consider the physical distance of the reference point from the test point and the characteristics of the RSSI. Since the range of RSSIs received from different Bluetooth transmitting devices (Beacons) in the same area is different, the cosine similarity difference is extremely small, and the influence of the reference point on the positioning result cannot be fully expressed. Therefore, in order to improve the positioning accuracy, this paper proposes a method of normalizing RSSI and a new weighted algorithm based on the physical distance and on the cosine similarity of the processed RSSI. Experiments in the actual environment show that the proposed algorithm has better positioning accuracy, and the average positioning accuracy is 1.816m, which is 36.41% higher than NN, 14.54% higher than KNN, 12.27% higher than wKNN and 12.78% higher than the physical distance algorithm.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"97 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":"127180663","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.2019.8834138
Yuexia Zhang, Jiacheng Jin, S. Yin
An improved frog-leap algorithm for job-shop scheduling is proposed. The algorithm forms frog individuals via process-based coding and utilizes the switched local search strategy to make frog individuals quickly find the minimum fitness function, thereby improving scheduling efficiency of the job shop. The proposed algorithm offers advantages, such as few parameters, simple implementation, strong global optimization ability, and dynamic balance between local and global searches. It offers means to effectively solve problems associated with job-shop scheduling.
{"title":"Hybrid frog-leap algorithm for job shop scheduling","authors":"Yuexia Zhang, Jiacheng Jin, S. Yin","doi":"10.1109/ICIEA.2019.8834138","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834138","url":null,"abstract":"An improved frog-leap algorithm for job-shop scheduling is proposed. The algorithm forms frog individuals via process-based coding and utilizes the switched local search strategy to make frog individuals quickly find the minimum fitness function, thereby improving scheduling efficiency of the job shop. The proposed algorithm offers advantages, such as few parameters, simple implementation, strong global optimization ability, and dynamic balance between local and global searches. It offers means to effectively solve problems associated with job-shop scheduling.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"7 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":"130009650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In order to improve the performance of permanent magnet synchronous motor (PMSM) driven by magnetic field directional control, an improved sliding mode observer (SMO) signal processing method is proposed. A structure based on second order generalized integrator (SOGI) is designed to extract the positive sequence components of the observed the back electromotive force (EMF). Compared with the traditional low-pass filter (LPF), the proposed structure has better filtering effect and almost no phase lag. Meanwhile, a phase locked loop (PLL) based on tangent function is proposed. Compared with the traditional PLL, the cutoff frequency of the tangent function based PLL is not affected by rotation speed and has a faster convergence rate. Simulation and experiments verify that the improved signal processing method of sliding mode observer can quickly and accurately track the position and speed of motor rotor, and the system has the characteristics of fast response and strong robustness.
{"title":"A Novel Signal Processing Method of Sliding Mode Observer for Position Sensorless PMSM Drives","authors":"Fuqiang Zhang, Shuai Dong, Jinxin Wang, Zhihao He, Qianfan Zhang","doi":"10.1109/ICIEA.2019.8834165","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834165","url":null,"abstract":"In order to improve the performance of permanent magnet synchronous motor (PMSM) driven by magnetic field directional control, an improved sliding mode observer (SMO) signal processing method is proposed. A structure based on second order generalized integrator (SOGI) is designed to extract the positive sequence components of the observed the back electromotive force (EMF). Compared with the traditional low-pass filter (LPF), the proposed structure has better filtering effect and almost no phase lag. Meanwhile, a phase locked loop (PLL) based on tangent function is proposed. Compared with the traditional PLL, the cutoff frequency of the tangent function based PLL is not affected by rotation speed and has a faster convergence rate. Simulation and experiments verify that the improved signal processing method of sliding mode observer can quickly and accurately track the position and speed of motor rotor, and the system has the characteristics of fast response and strong robustness.","PeriodicalId":311302,"journal":{"name":"2019 14th IEEE Conference on Industrial Electronics and Applications (ICIEA)","volume":"2 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":"128960153","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.2019.8833830
Yuxiang Chen, Yongji Wang, Lei Liu, Zhongtao Cheng, Ye Yang
This paper proposes an on-board rapid planning guidance for the boost phase of multistage rockets, based on the Sequential Quadratic Programming (SQP). Firstly, based on the multistage rocket model, Particle Swarm Optimization (PSO) algorithm is used for achieving an initial trajectory by flight trajectory optimization. Secondly, considering the varieties of constrain limits and aerodynamics deviation, an improved SQP algorithm is used for on-board trajectory planning. Finally, numerical simulation results show that on-board trajectory planning problems with multiple constrain limits and uncertain aerodynamic coefficient can be solved by SQP effectively.
{"title":"An On-board Rapid Planning Method for Booster Trajectory of Multistage Rocket","authors":"Yuxiang Chen, Yongji Wang, Lei Liu, Zhongtao Cheng, Ye Yang","doi":"10.1109/ICIEA.2019.8833830","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833830","url":null,"abstract":"This paper proposes an on-board rapid planning guidance for the boost phase of multistage rockets, based on the Sequential Quadratic Programming (SQP). Firstly, based on the multistage rocket model, Particle Swarm Optimization (PSO) algorithm is used for achieving an initial trajectory by flight trajectory optimization. Secondly, considering the varieties of constrain limits and aerodynamics deviation, an improved SQP algorithm is used for on-board trajectory planning. Finally, numerical simulation results show that on-board trajectory planning problems with multiple constrain limits and uncertain aerodynamic coefficient can be solved by SQP 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":"129006218","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}
This paper introduces the research significance of control algorithm for automatic train operation, gives a brief description of the basic composition and function of automatic train operation system. Introduced and analyzed the development status of train automatic driving control algorithm and explains the advantages and disadvantages of some control algorithms. Finally, the prospect of train automatic driving control algorithm is prospected.
{"title":"A Survey of Control Algorithm for Automatic Train Operation","authors":"Xuanna Chen, Weigang Ma, Guo Xie, Xinhong Hei, Feng Wang, Siyu Tan","doi":"10.1109/ICIEA.2019.8833794","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8833794","url":null,"abstract":"This paper introduces the research significance of control algorithm for automatic train operation, gives a brief description of the basic composition and function of automatic train operation system. Introduced and analyzed the development status of train automatic driving control algorithm and explains the advantages and disadvantages of some control algorithms. Finally, the prospect of train automatic driving control algorithm is prospected.","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":"131036061","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.2019.8834381
Jianhua Wang, Gaojie Yu, Liu Zhong, Weihai Chen, Yu Sun
Electroencephalography (EEG) signal recorded during motor imagery (MI) has been widely applied in noninvasive brain-computer interfaces (BCIs) as a communication approach. As an important issue in BCI systems, signal classification has been attached to increasingly attention. This paper presents a new classification method based on the deep convolutional neural network (CNN) for MI-EEG. Compared with other three classification methods (LDA, SVM, MLP), the results demonstrate that CNN can provide better classification performance. The present study shows that the proposed method is effective to classify MI and have potential to be a proper choice for BCI applications. The proposed paradigm could be further implemented by optimizing the network structure.
{"title":"Classification of EEG signal using convolutional neural networks","authors":"Jianhua Wang, Gaojie Yu, Liu Zhong, Weihai Chen, Yu Sun","doi":"10.1109/ICIEA.2019.8834381","DOIUrl":"https://doi.org/10.1109/ICIEA.2019.8834381","url":null,"abstract":"Electroencephalography (EEG) signal recorded during motor imagery (MI) has been widely applied in noninvasive brain-computer interfaces (BCIs) as a communication approach. As an important issue in BCI systems, signal classification has been attached to increasingly attention. This paper presents a new classification method based on the deep convolutional neural network (CNN) for MI-EEG. Compared with other three classification methods (LDA, SVM, MLP), the results demonstrate that CNN can provide better classification performance. The present study shows that the proposed method is effective to classify MI and have potential to be a proper choice for BCI applications. The proposed paradigm could be further implemented by optimizing the network structure.","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":"131044950","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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