Pub Date : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00054
Jiaming Guo, J. Xiang, Hongwei Chen
Based on thermal-elastohydrodynamic lubrication and micro-convex peak contact theory, the calculation model of thermal-elastic fluid for connecting rod small-end bearing was established. The lubrication and friction characteristics of the small-end bearing were analyzed. The heat generation and dissipation mechanism and heat distribution rule of small-end bearing were obtained. The effect of cylinder pressure, rotation speed and roughness of small-end bearing surface on heat generation and heat transfer was discussed. The results show that the connecting rod small-end bearing is mostly in the state of mixed lubrication during the movement, and the heat is generated mainly through the friction on the bearing surface; the bearing mainly dissipates heat by means of heat conduction through small-end and piston pin. Piston pin and bushing accounted for 99.8% of heat dissipation, while the heat dissipation through lubricating oil out of bearing is relatively small. Cylinder pressure, rotation speed and roughness have great influence on the heat generation of the bearing. The increase of cylinder pressure will cause the total friction power loss of bearing increases. With the increase of rotation speed, the total friction power loss always increases after reduces. The increase of roughness also increases the friction power loss of bearing. The change of total friction power loss of the bearing mainly ranges from crankshaft angle 270°CA to 630°CA. Cylinder pressure, rotation speed and roughness have little influence on heat distribution rule of bearing. The increase of cylinder pressure and rotation speed is beneficial to the heat dissipation of lubricating oil, while the increase of roughness is not conducive to the heat dissipation of lubricating oil.
{"title":"Study on heat generation and dissipation characteristics of connecting rod small-end bearing in diesel engine","authors":"Jiaming Guo, J. Xiang, Hongwei Chen","doi":"10.1109/WCEEA56458.2022.00054","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00054","url":null,"abstract":"Based on thermal-elastohydrodynamic lubrication and micro-convex peak contact theory, the calculation model of thermal-elastic fluid for connecting rod small-end bearing was established. The lubrication and friction characteristics of the small-end bearing were analyzed. The heat generation and dissipation mechanism and heat distribution rule of small-end bearing were obtained. The effect of cylinder pressure, rotation speed and roughness of small-end bearing surface on heat generation and heat transfer was discussed. The results show that the connecting rod small-end bearing is mostly in the state of mixed lubrication during the movement, and the heat is generated mainly through the friction on the bearing surface; the bearing mainly dissipates heat by means of heat conduction through small-end and piston pin. Piston pin and bushing accounted for 99.8% of heat dissipation, while the heat dissipation through lubricating oil out of bearing is relatively small. Cylinder pressure, rotation speed and roughness have great influence on the heat generation of the bearing. The increase of cylinder pressure will cause the total friction power loss of bearing increases. With the increase of rotation speed, the total friction power loss always increases after reduces. The increase of roughness also increases the friction power loss of bearing. The change of total friction power loss of the bearing mainly ranges from crankshaft angle 270°CA to 630°CA. Cylinder pressure, rotation speed and roughness have little influence on heat distribution rule of bearing. The increase of cylinder pressure and rotation speed is beneficial to the heat dissipation of lubricating oil, while the increase of roughness is not conducive to the heat dissipation of lubricating oil.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126882491","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00066
Zan Yang, Jiabin Chen, Weicheng Wang, Lifang Shi
Research and implementation of a parallel algorithm that simultaneously executes other business tasks while high-precision fixed-point hovering indoors and outdoors, which run in the multi-core airborne pilot computer on rotorcraft UA V, and supported by GNSS-RTK or UWB and other positioning technologies. It is mainly used for the situation that business tasks have higher requirements for the positioning point, in this case, if the strong air flow affects the positioning effect, and the flight controller itself cannot correct the position in time, it will affect the business task execution effect or even make the task unable to perform correctly. The algorithm was tested several times in the actual project scenario, and compared with the situation that the algorithm was not used, the average completion rate of business tasks increased from about 84 % to more than 98%, exceeding the lower design limit requirements of this project (96.4%), and in the case of sufficient computing power of the airborne computer, it did not have a significant impact on the original execution rate of the service. The code implemented according to this algorithm currently runs on the multi-core computing equipment outside the flight controller, and does not affect the flight controller to control the attitude of UA V. After large number of actual measurements, no accident such as crashes and collisions caused by this algorithm, its safety is assured.
{"title":"The Hover Anti-Wind Parallel Algorithm Running in Airborne Computer Which on Rotorcraft Drone","authors":"Zan Yang, Jiabin Chen, Weicheng Wang, Lifang Shi","doi":"10.1109/WCEEA56458.2022.00066","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00066","url":null,"abstract":"Research and implementation of a parallel algorithm that simultaneously executes other business tasks while high-precision fixed-point hovering indoors and outdoors, which run in the multi-core airborne pilot computer on rotorcraft UA V, and supported by GNSS-RTK or UWB and other positioning technologies. It is mainly used for the situation that business tasks have higher requirements for the positioning point, in this case, if the strong air flow affects the positioning effect, and the flight controller itself cannot correct the position in time, it will affect the business task execution effect or even make the task unable to perform correctly. The algorithm was tested several times in the actual project scenario, and compared with the situation that the algorithm was not used, the average completion rate of business tasks increased from about 84 % to more than 98%, exceeding the lower design limit requirements of this project (96.4%), and in the case of sufficient computing power of the airborne computer, it did not have a significant impact on the original execution rate of the service. The code implemented according to this algorithm currently runs on the multi-core computing equipment outside the flight controller, and does not affect the flight controller to control the attitude of UA V. After large number of actual measurements, no accident such as crashes and collisions caused by this algorithm, its safety is assured.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131162097","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00040
Peigang Xu, Jing Zeng, Gang He, Tingting Xie, Lin Yu, Lei Xu
Based on the TRIZ theory and the analysis of the object field, it was introduced into the design improvement process of the separation wheel in the PROTOS 90 type rolling and packaging machine, and the design of the separation wheel of the tobacco rod packaging was improved through the structural carding and rolling machine functional device. The basic functions and structures of a series of reel packaging machines were analyzed, and a functional model was established by substance-field analysis and checking the standard solutions, and a solution was generated. The feasibility and effectiveness of the method are verified by the actual machine. Taking the design improvement of the splicer as an example, it verifies the specific application of TRIZ theory and provides a useful reference, and provides more scientific methods and tools for the subsequent equipment improvement and upgrading.
{"title":"Improvement in the Design of Separating Roller for PROTOS 90 Cigarette Making & Packaging Machine Based on the TRIZ Theory","authors":"Peigang Xu, Jing Zeng, Gang He, Tingting Xie, Lin Yu, Lei Xu","doi":"10.1109/WCEEA56458.2022.00040","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00040","url":null,"abstract":"Based on the TRIZ theory and the analysis of the object field, it was introduced into the design improvement process of the separation wheel in the PROTOS 90 type rolling and packaging machine, and the design of the separation wheel of the tobacco rod packaging was improved through the structural carding and rolling machine functional device. The basic functions and structures of a series of reel packaging machines were analyzed, and a functional model was established by substance-field analysis and checking the standard solutions, and a solution was generated. The feasibility and effectiveness of the method are verified by the actual machine. Taking the design improvement of the splicer as an example, it verifies the specific application of TRIZ theory and provides a useful reference, and provides more scientific methods and tools for the subsequent equipment improvement and upgrading.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131360081","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00021
Jun Liu, Rui Zhao
High-voltage isolating switches are used in the electric industry in common. But in the railway industry, it is one of the key components of locomotives. It's function of isolating 25KV electricity running in the special net of the railway, preventing danger of the high-voltage for the locomotive crew life and protecting the locomotive performance. At present, the high-voltage isolating switch still adopts manual detection and maintenance. There are some shortcomings such as inaccurate measurement data, low precision, and poor stability. This paper has given a bench plan which structures are designed in detail. The control principle, precision calculation, and stability prin-ciple of the bench are briefly explained. According to the plan, the test bench built can meet the requirements of the industry standard. At the same time, the test bench has some structure automatic functions such as testing and printing, and the equipment that has been put into production is in good condition. It is served in the plant of advanced locomotive mainte-nance and has good performance.
{"title":"High voltage isolating switch testing bench for “HeXie” electric locomotives","authors":"Jun Liu, Rui Zhao","doi":"10.1109/WCEEA56458.2022.00021","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00021","url":null,"abstract":"High-voltage isolating switches are used in the electric industry in common. But in the railway industry, it is one of the key components of locomotives. It's function of isolating 25KV electricity running in the special net of the railway, preventing danger of the high-voltage for the locomotive crew life and protecting the locomotive performance. At present, the high-voltage isolating switch still adopts manual detection and maintenance. There are some shortcomings such as inaccurate measurement data, low precision, and poor stability. This paper has given a bench plan which structures are designed in detail. The control principle, precision calculation, and stability prin-ciple of the bench are briefly explained. According to the plan, the test bench built can meet the requirements of the industry standard. At the same time, the test bench has some structure automatic functions such as testing and printing, and the equipment that has been put into production is in good condition. It is served in the plant of advanced locomotive mainte-nance and has good performance.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121633536","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00011
Tan-En Wang, Hao Wang, Gang Wu, Bolong Chen, Xuyi Liang
Aiming at the problem of high replacement and maintenance cost of communication power battery, this paper studies the intelligent lithium iron phosphate battery hybrid system. The economic requirements of communication power supply are fully considered. For the problems of battery aging and insufficient charge and discharge in the use of communication power supply batteries, the battery management system of lead-acid battery and lithium iron phosphate battery is studied. Through system optimization and software and hardware design, the service life of the battery can be effectively increased by about 33%. The test results show that the hybrid system can effectively improve the service efficiency of the battery, make its charge and discharge more fully, and avoid the aging problem caused by system isolation. The experiments of voltage test, state of charge estimation and equalization test show that the system has good effect. In terms of economy, the intelligent lithium iron phosphate battery hybrid system can effectively save about 43.3 % of the construction cost of the network base station, which has a good application prospect.
{"title":"A Study on the Hybrid System of Intelligent Lithium Iron Phosphate Battery Based on Economic Communication Power Model","authors":"Tan-En Wang, Hao Wang, Gang Wu, Bolong Chen, Xuyi Liang","doi":"10.1109/WCEEA56458.2022.00011","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00011","url":null,"abstract":"Aiming at the problem of high replacement and maintenance cost of communication power battery, this paper studies the intelligent lithium iron phosphate battery hybrid system. The economic requirements of communication power supply are fully considered. For the problems of battery aging and insufficient charge and discharge in the use of communication power supply batteries, the battery management system of lead-acid battery and lithium iron phosphate battery is studied. Through system optimization and software and hardware design, the service life of the battery can be effectively increased by about 33%. The test results show that the hybrid system can effectively improve the service efficiency of the battery, make its charge and discharge more fully, and avoid the aging problem caused by system isolation. The experiments of voltage test, state of charge estimation and equalization test show that the system has good effect. In terms of economy, the intelligent lithium iron phosphate battery hybrid system can effectively save about 43.3 % of the construction cost of the network base station, which has a good application prospect.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"142 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130651520","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00059
Ling Pan, Yingjie Tian, Qian Feng, Xiaofeng Zou
Under the background of high power electronic rate in city grid, power system presents the characteristics of multiple nonlinear customers interaction, which aggravates the harmonic pollution. Besides, the fluctuation of background harmonics becomes more severe, and certain correlations exist among the harmonic emission properties of different harmonic sources. As a result, there will be new challenges in the quantification of harmonic responsibility. In this paper, a sparse component analysis-based method is proposed to solve this problem. Through sparse transformation of the source signals, the measured harmonic voltage and current signals will be clustered linearly. The slope of the clustering line can be used to calculate the harmonic impedance, and then the harmonic responsibility can be quantified. The proposed method can ensure a high calculation accuracy even when background harmonics fluctuate greatly and each harmonic source is no longer independent. The feasibility of the proposed method is verified by simulation analysis.
{"title":"Evaluation method of harmonic emission level under the influence of multivariate nonlinear customer interaction","authors":"Ling Pan, Yingjie Tian, Qian Feng, Xiaofeng Zou","doi":"10.1109/WCEEA56458.2022.00059","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00059","url":null,"abstract":"Under the background of high power electronic rate in city grid, power system presents the characteristics of multiple nonlinear customers interaction, which aggravates the harmonic pollution. Besides, the fluctuation of background harmonics becomes more severe, and certain correlations exist among the harmonic emission properties of different harmonic sources. As a result, there will be new challenges in the quantification of harmonic responsibility. In this paper, a sparse component analysis-based method is proposed to solve this problem. Through sparse transformation of the source signals, the measured harmonic voltage and current signals will be clustered linearly. The slope of the clustering line can be used to calculate the harmonic impedance, and then the harmonic responsibility can be quantified. The proposed method can ensure a high calculation accuracy even when background harmonics fluctuate greatly and each harmonic source is no longer independent. The feasibility of the proposed method is verified by simulation analysis.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131441060","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00053
Zhicheng Zhu, Rongbao Kang, Wei Zhang, Kun Lan, Yuguang Zhang
Protecting critical information infrastructure is a frontier of current cyberspace security research. This paper firstly introduces the concepts and common methods of topology inference and topology obfuscation. Then, an improved topology obfuscation method is proposed for active topology inference represented by trace route. It improves the selection algorithm of deployment nodes, adding virtual nodes and links by replicating the key topologies of the real network. For attackers who use traceroute for topology inference, this method will mislead them to obtain wrong node importance ranking. Finally, the simulation results show that the proposed topology obfuscation method can effectively against active topology inference in typical star-structured topology network.
{"title":"A Technique of Topology Obfuscation Against Active Topology Inference","authors":"Zhicheng Zhu, Rongbao Kang, Wei Zhang, Kun Lan, Yuguang Zhang","doi":"10.1109/WCEEA56458.2022.00053","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00053","url":null,"abstract":"Protecting critical information infrastructure is a frontier of current cyberspace security research. This paper firstly introduces the concepts and common methods of topology inference and topology obfuscation. Then, an improved topology obfuscation method is proposed for active topology inference represented by trace route. It improves the selection algorithm of deployment nodes, adding virtual nodes and links by replicating the key topologies of the real network. For attackers who use traceroute for topology inference, this method will mislead them to obtain wrong node importance ranking. Finally, the simulation results show that the proposed topology obfuscation method can effectively against active topology inference in typical star-structured topology network.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123719088","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 fabrication process of UNS S32760 super duplex stainless steel tubes is introduced in this paper. Through the research and optimization of the hot piercing process, the quality of S32760 tube products is controlled from the source; By adjusting and optimizing the parameters of the cold rolling mill, not only the dimensional accuracy is guaranteed, but also the quality of the internal and external surfaces is improved; and as the result of the exploration on the solid solution treatment process of the S32760 tube intermediate and finished products, all product performance indicators in the final inspection meet the relevant standards and user requirements.
{"title":"A Study on the Fabrication Process of UNS S32760 Super Duplex Seamless Steel Tubes","authors":"Xuhuai Chen, Shengda Cong, Qi Shao, Hongjun Shi, Guoqiang Wu","doi":"10.1109/WCEEA56458.2022.00049","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00049","url":null,"abstract":"The fabrication process of UNS S32760 super duplex stainless steel tubes is introduced in this paper. Through the research and optimization of the hot piercing process, the quality of S32760 tube products is controlled from the source; By adjusting and optimizing the parameters of the cold rolling mill, not only the dimensional accuracy is guaranteed, but also the quality of the internal and external surfaces is improved; and as the result of the exploration on the solid solution treatment process of the S32760 tube intermediate and finished products, all product performance indicators in the final inspection meet the relevant standards and user requirements.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123882051","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 : 2022-10-01DOI: 10.1109/WCEEA56458.2022.00033
Fang Yuan, Dong Li, Wencui Li, Xiao Feng, Yao Zhao
The preparation of maintenance plan of power grid is directly related to the safe and reliable operation of all kinds of equipment in the power grid and the reliable power supply of power users, which is an important work content of power grid dispatching management department. Different importance of different equipment should be considered in making maintenance plan of regional power grid. Aiming at different types of equipment, this study optimizes the equipment maintenance plan and arranges different maintenance time, thus reducing the maintenance cost. This optimization method has strong practical significance in the process of making maintenance plan, and can be widely used in practical projects.
{"title":"Research on the Optimization Method of Power Network Maintenance Plan Based on Equipment Importance","authors":"Fang Yuan, Dong Li, Wencui Li, Xiao Feng, Yao Zhao","doi":"10.1109/WCEEA56458.2022.00033","DOIUrl":"https://doi.org/10.1109/WCEEA56458.2022.00033","url":null,"abstract":"The preparation of maintenance plan of power grid is directly related to the safe and reliable operation of all kinds of equipment in the power grid and the reliable power supply of power users, which is an important work content of power grid dispatching management department. Different importance of different equipment should be considered in making maintenance plan of regional power grid. Aiming at different types of equipment, this study optimizes the equipment maintenance plan and arranges different maintenance time, thus reducing the maintenance cost. This optimization method has strong practical significance in the process of making maintenance plan, and can be widely used in practical projects.","PeriodicalId":143024,"journal":{"name":"2022 International Conference on Wireless Communications, Electrical Engineering and Automation (WCEEA)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114853791","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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