In the design of a three-phase photovoltaic grid-connected inverter system, the control strategy usually adopts hysteresis loop current control. To solve this problem, space vector-asymmetric double hysteresisloop current control method is introduced, which can reduce the switching frequency and the switching loss to a certain extent and realize the grid-connected current power factor close to 1. The simulation models based on the three-phase stationary coordinate system and two-phase stationary coordinate system are built-in Matlab/Simulink simulation platform respectively. The two control strategies are compared and analyzed in terms of grid-connected current and voltage, switching frequency, power factor, etc. The simulation results verify the correctness of the control scheme.
{"title":"A hysteresis loop control method for output current of three-phase photovoltaic grid-connected inverters","authors":"Bin Wang, Ying Shi, Xin Gao","doi":"10.1145/3548608.3561132","DOIUrl":"https://doi.org/10.1145/3548608.3561132","url":null,"abstract":"In the design of a three-phase photovoltaic grid-connected inverter system, the control strategy usually adopts hysteresis loop current control. To solve this problem, space vector-asymmetric double hysteresisloop current control method is introduced, which can reduce the switching frequency and the switching loss to a certain extent and realize the grid-connected current power factor close to 1. The simulation models based on the three-phase stationary coordinate system and two-phase stationary coordinate system are built-in Matlab/Simulink simulation platform respectively. The two control strategies are compared and analyzed in terms of grid-connected current and voltage, switching frequency, power factor, etc. The simulation results verify the correctness of the control scheme.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123354023","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 proposes a batteryless pedometer device. It is a wearable device which can sufficiently collect motional energy during human movements and convert it into electrical energy to power the pedometer. To achieve functions mentioned above, this paper first introduces a low-cost implementation scheme for the pedometer, including sensor, microprocessor, and a wireless communication protocol. Secondly, the paper gives a scheme about motion energy capture and power supply, including a swing energy capture device that match the motion characteristic and an efficient power management unit. Lastly, a prototype of the pedometer device and its corresponding user interface are established to verify the feasibility of above sections from the perspective of functional realization.
{"title":"Design and Implementation of a Batteryless Pedometer based on a Motion Tracking Sensor","authors":"Daiyuan Jing","doi":"10.1145/3548608.3561131","DOIUrl":"https://doi.org/10.1145/3548608.3561131","url":null,"abstract":"This paper proposes a batteryless pedometer device. It is a wearable device which can sufficiently collect motional energy during human movements and convert it into electrical energy to power the pedometer. To achieve functions mentioned above, this paper first introduces a low-cost implementation scheme for the pedometer, including sensor, microprocessor, and a wireless communication protocol. Secondly, the paper gives a scheme about motion energy capture and power supply, including a swing energy capture device that match the motion characteristic and an efficient power management unit. Lastly, a prototype of the pedometer device and its corresponding user interface are established to verify the feasibility of above sections from the perspective of functional realization.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114153967","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}
Zhuangzhuang Wang, Jianchao Huang, Shujing Chen, Zejun Zhang, Zhiming Cai
Traditional correlation filtering algorithms limit the tracking performance in complex scenes because they cannot fully utilize the features of the target. To solve this problem, a multi-feature adaptive fusion target tracking algorithm is proposed in this paper. First, the HOG feature, CN feature and Gray feature of the target are extracted respectively, and the CN feature and Gray feature are linearly splined into color feature by cat function to improve the discriminability of feature representation in the tracking process. Then, the maximum response values of HOG feature and color feature are calculated respectively, and the response values are normalized. Finally, the fusion weights of the features are determined according to the normalization results, and the adaptive fusion of the features is realized in the response layer. In order to ensure the feasibility of feature fusion, APCE value was introduced in this paper to compare the indicators before and after fusion, and experiments were conducted on OTB2015. The results show that the algorithm presented in this paper has significantly improved the success rate and accuracy, and has good robustness to deal with complex environments.
{"title":"Target Tracking Algorithm Based on Multi-feature Adaptive Fusion in Complex Scenes","authors":"Zhuangzhuang Wang, Jianchao Huang, Shujing Chen, Zejun Zhang, Zhiming Cai","doi":"10.1145/3548608.3559213","DOIUrl":"https://doi.org/10.1145/3548608.3559213","url":null,"abstract":"Traditional correlation filtering algorithms limit the tracking performance in complex scenes because they cannot fully utilize the features of the target. To solve this problem, a multi-feature adaptive fusion target tracking algorithm is proposed in this paper. First, the HOG feature, CN feature and Gray feature of the target are extracted respectively, and the CN feature and Gray feature are linearly splined into color feature by cat function to improve the discriminability of feature representation in the tracking process. Then, the maximum response values of HOG feature and color feature are calculated respectively, and the response values are normalized. Finally, the fusion weights of the features are determined according to the normalization results, and the adaptive fusion of the features is realized in the response layer. In order to ensure the feasibility of feature fusion, APCE value was introduced in this paper to compare the indicators before and after fusion, and experiments were conducted on OTB2015. The results show that the algorithm presented in this paper has significantly improved the success rate and accuracy, and has good robustness to deal with complex environments.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121259094","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 article introduces the research background of the layout problem of circular parts, classifies the layout problems of circular parts, and then analyzes the layout pattern of the test questions. Finally, the factors that affect the utilization rate of the plate include the blank species, the number and length of the cutting blade.
{"title":"Research on the Problem of Circular Blank Based on Shear Cutting","authors":"Jun Ji, Haijun Zhou, Feifei Xing","doi":"10.1145/3548608.3559246","DOIUrl":"https://doi.org/10.1145/3548608.3559246","url":null,"abstract":"This article introduces the research background of the layout problem of circular parts, classifies the layout problems of circular parts, and then analyzes the layout pattern of the test questions. Finally, the factors that affect the utilization rate of the plate include the blank species, the number and length of the cutting blade.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121860411","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}
Xinyue Chai, Mengqian Cheng, Quangu Chen, Xiaoqin Song, Tiecheng Song
In Intelligent Transportation Systems(ITS), vehicles are mainly considered to travel in vehicle groups on highways, and in cities, C-V2X is more prone to data eavesdropping when communi-cating at vehicle convergence sections such as intersections, and with limited spectrum resources, communication quality needs to be guaranteed and enhanced. It is a great challenge to improve the spectrum efficiency (SE) and energy efficiency (EE) of the V2X network while satisfying the C-V2X confidentiality rate. To solve this problem, this paper proposes a deep reinforcement learning based SE and EE enhancement algorithm. It establishes an objective optimization function that considers both SE and EE, and uses the secrecy rate of C-V2X as the key constraint of this function. The optimization problem is transformed into a spec-trum and transmission power selection problem for V2V and V2I links using the Deep-Q-Network ( DQN ). The simulation results show that the overall efficiency and V2V link secrecy rate of the proposed algorithm is significantly higher than that of the ran-dom algorithm when the number of vehicles is between 20 and 40, with an average secrecy rate increase of 82.86%.
{"title":"An energy-efficient V2X Resource Allocation for User Privacy Protection: A Learning-Based Approach","authors":"Xinyue Chai, Mengqian Cheng, Quangu Chen, Xiaoqin Song, Tiecheng Song","doi":"10.1145/3548608.3559210","DOIUrl":"https://doi.org/10.1145/3548608.3559210","url":null,"abstract":"In Intelligent Transportation Systems(ITS), vehicles are mainly considered to travel in vehicle groups on highways, and in cities, C-V2X is more prone to data eavesdropping when communi-cating at vehicle convergence sections such as intersections, and with limited spectrum resources, communication quality needs to be guaranteed and enhanced. It is a great challenge to improve the spectrum efficiency (SE) and energy efficiency (EE) of the V2X network while satisfying the C-V2X confidentiality rate. To solve this problem, this paper proposes a deep reinforcement learning based SE and EE enhancement algorithm. It establishes an objective optimization function that considers both SE and EE, and uses the secrecy rate of C-V2X as the key constraint of this function. The optimization problem is transformed into a spec-trum and transmission power selection problem for V2V and V2I links using the Deep-Q-Network ( DQN ). The simulation results show that the overall efficiency and V2V link secrecy rate of the proposed algorithm is significantly higher than that of the ran-dom algorithm when the number of vehicles is between 20 and 40, with an average secrecy rate increase of 82.86%.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"161 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127619860","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 characteristics of Imported coal Machinery directly restricts the efficiency of spare parts localization. For this reason, the paper introduced reverse engineering and introduced three key techniques of spare parts localization in reverse engineering, gathering data, building 3D model, generating the engineering drawings and application instance, the reverse engineering has a positive effect to improve the efficiency of the spare parts localization.
{"title":"The Application of Reverse Engineering for Coal Machinery spare parts","authors":"Tingfeng Song","doi":"10.1145/3548608.3559228","DOIUrl":"https://doi.org/10.1145/3548608.3559228","url":null,"abstract":"The characteristics of Imported coal Machinery directly restricts the efficiency of spare parts localization. For this reason, the paper introduced reverse engineering and introduced three key techniques of spare parts localization in reverse engineering, gathering data, building 3D model, generating the engineering drawings and application instance, the reverse engineering has a positive effect to improve the efficiency of the spare parts localization.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131781137","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 three-dimensional reconstruction of vehicle surface point cloud can provide effective reference data for robot path planning of vehicle surface spraying. A three-dimensional data measurement method of vehicle surface based on line laser sensor is proposed in this paper. This paper collects the point cloud information of vehicle surface by line laser sensor, extracts the effective three-dimensional information of vehicle surface. and takes the regular block and vehicle model as the experimental object, use the measurement system with the sensor clamped by the manipulator to measure the three-dimensional data, compare the point cloud data accuracy under different measurement depth and scanning speed, and reconstruct the vehicle model. The research shows that this method is feasible.
{"title":"Research on vehicle 3D data measurement method based on line laser scanning","authors":"Qi Liu, Xin Jin, Yu-di Zou, Wei Zhang","doi":"10.1145/3548608.3559276","DOIUrl":"https://doi.org/10.1145/3548608.3559276","url":null,"abstract":"The three-dimensional reconstruction of vehicle surface point cloud can provide effective reference data for robot path planning of vehicle surface spraying. A three-dimensional data measurement method of vehicle surface based on line laser sensor is proposed in this paper. This paper collects the point cloud information of vehicle surface by line laser sensor, extracts the effective three-dimensional information of vehicle surface. and takes the regular block and vehicle model as the experimental object, use the measurement system with the sensor clamped by the manipulator to measure the three-dimensional data, compare the point cloud data accuracy under different measurement depth and scanning speed, and reconstruct the vehicle model. The research shows that this method is feasible.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134620678","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}
Xinfeng Fan, M. Huang, T. Yang, Chen Fu, Yi Wan, Guanghui Shang
In order to achieve clean and precise assembly, the visual alignment system is often used in production to eliminate installation errors. However, the system actuator, UVW platform has the problem that the working space is difficult to solve, and the working boundary is difficult to accurately calculate, which affects the system alignment accuracy. To solve the above problems, this paper started from the structure, degree of freedom and plane model of the platform, solved the positive and negative solution equations of the platform position, and analyzed the singularity of the platform. By using the movement characteristics of platform 2 translation and 1 rotation, the XYθ three-dimensional workspace was constructed, and the shape and size change process of the platform working space were analyzed through the layered analysis method. It can be seen from the simulation results that the three-dimensional workspace can accurately obtain both the working boundary of the platform and the distribution of point clouds, which provides a basis for precise control of the platform.
{"title":"Analysis of the Workspace of UVW Platform","authors":"Xinfeng Fan, M. Huang, T. Yang, Chen Fu, Yi Wan, Guanghui Shang","doi":"10.1145/3548608.3559220","DOIUrl":"https://doi.org/10.1145/3548608.3559220","url":null,"abstract":"In order to achieve clean and precise assembly, the visual alignment system is often used in production to eliminate installation errors. However, the system actuator, UVW platform has the problem that the working space is difficult to solve, and the working boundary is difficult to accurately calculate, which affects the system alignment accuracy. To solve the above problems, this paper started from the structure, degree of freedom and plane model of the platform, solved the positive and negative solution equations of the platform position, and analyzed the singularity of the platform. By using the movement characteristics of platform 2 translation and 1 rotation, the XYθ three-dimensional workspace was constructed, and the shape and size change process of the platform working space were analyzed through the layered analysis method. It can be seen from the simulation results that the three-dimensional workspace can accurately obtain both the working boundary of the platform and the distribution of point clouds, which provides a basis for precise control of the platform.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115703702","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 wide application of Carbon Fiber Reinforced Polymer (CFRP) in aerospace, transportation and other fields, it is of great significance to inspect its structural integrity. Aiming at the carbon fiber composite used in aviation equipment, a frequency difference electrical impedance tomography (fdEIT) detection method is proposed. This method can realize the structural damage detection of carbon fiber composites without prior information. Combined with previous research, the article adopts the structure of evenly arranging electrodes around the CFRP laminate, and on this basis, analyzes and compares four excitation measurement strategies. The finite element analysis software is used to construct three common damages in CFRP laminates, and multiple evaluation indicators are used to evaluate the use effect of the four excitation methods from the perspective of measurement data and image reconstruction effect. The results show that the excitation mode of electrodes with one electrode interval has a good effect on the detection of typical impact damage and delamination damage, and the overall performance is relatively good, which provides a reference for the next research.
{"title":"Research on frequency difference EIT excitation strategy for CFRP composites","authors":"W. Fan, Pengchao Zhang","doi":"10.1145/3548608.3559229","DOIUrl":"https://doi.org/10.1145/3548608.3559229","url":null,"abstract":"With the wide application of Carbon Fiber Reinforced Polymer (CFRP) in aerospace, transportation and other fields, it is of great significance to inspect its structural integrity. Aiming at the carbon fiber composite used in aviation equipment, a frequency difference electrical impedance tomography (fdEIT) detection method is proposed. This method can realize the structural damage detection of carbon fiber composites without prior information. Combined with previous research, the article adopts the structure of evenly arranging electrodes around the CFRP laminate, and on this basis, analyzes and compares four excitation measurement strategies. The finite element analysis software is used to construct three common damages in CFRP laminates, and multiple evaluation indicators are used to evaluate the use effect of the four excitation methods from the perspective of measurement data and image reconstruction effect. The results show that the excitation mode of electrodes with one electrode interval has a good effect on the detection of typical impact damage and delamination damage, and the overall performance is relatively good, which provides a reference for the next research.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115838093","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}
Jinlong Wang, Jiewen Sun, Xianbo Xue, Yue Qu, R. Bai, Bing Zhang, Yingru Wang
Intelligent gas wells are an important means to control water cut, gas production and efficient development for gas reservoirs with bottom water. The development of hydraulic flow control valve is the key for the core completion tool of intelligent gas wells. Compared with the hydraulic flow control valve of intelligent completion for oil and water wells, the tightness requirements between the flow trim and the sliding sleeve of the hydraulic flow control valve in intelligent gas well are higher, and the sliding sleeve positioning requires more precise. The development of hydraulic flow control valve for intelligent gas wells in this paper adopts adjustable locking mechanism that can realize accurately locate the position of the sliding sleeve by setting different numbers of springs and adjusting the elastic force of the springs to adjust the hydraulic unlocking force. The dual sealing structure of metal seal and O-ring seal is adopted between the flow trim and the sliding sleeve to solve the gas tightness of the tool. The combination of laboratory experiment and fluid simulation analysis was used to first time confirm the shape of the valve hole suitable for hydraulic flow control valve for gas wells. Through the self-developed intelligent completion simulation system experiment, it can be seen that the pressure equalization and production control effect are good in the double-segment for water control and gas production process, and the gas production of a single well is increased by 17.8%, which can be combined with the downhole hydraulic reversing control system to form a low-cost intelligent gas well system to use in gas wells above 3000m. The development of hydraulic flow control valve has filled the gaps in the research of Chinese intelligent gas wells, and it has great significance in the theoretical research and practical application.
{"title":"Development of Hydraulic Flow Control Valve for Intelligent Gas Well","authors":"Jinlong Wang, Jiewen Sun, Xianbo Xue, Yue Qu, R. Bai, Bing Zhang, Yingru Wang","doi":"10.1145/3548608.3559244","DOIUrl":"https://doi.org/10.1145/3548608.3559244","url":null,"abstract":"Intelligent gas wells are an important means to control water cut, gas production and efficient development for gas reservoirs with bottom water. The development of hydraulic flow control valve is the key for the core completion tool of intelligent gas wells. Compared with the hydraulic flow control valve of intelligent completion for oil and water wells, the tightness requirements between the flow trim and the sliding sleeve of the hydraulic flow control valve in intelligent gas well are higher, and the sliding sleeve positioning requires more precise. The development of hydraulic flow control valve for intelligent gas wells in this paper adopts adjustable locking mechanism that can realize accurately locate the position of the sliding sleeve by setting different numbers of springs and adjusting the elastic force of the springs to adjust the hydraulic unlocking force. The dual sealing structure of metal seal and O-ring seal is adopted between the flow trim and the sliding sleeve to solve the gas tightness of the tool. The combination of laboratory experiment and fluid simulation analysis was used to first time confirm the shape of the valve hole suitable for hydraulic flow control valve for gas wells. Through the self-developed intelligent completion simulation system experiment, it can be seen that the pressure equalization and production control effect are good in the double-segment for water control and gas production process, and the gas production of a single well is increased by 17.8%, which can be combined with the downhole hydraulic reversing control system to form a low-cost intelligent gas well system to use in gas wells above 3000m. The development of hydraulic flow control valve has filled the gaps in the research of Chinese intelligent gas wells, and it has great significance in the theoretical research and practical application.","PeriodicalId":201434,"journal":{"name":"Proceedings of the 2022 2nd International Conference on Control and Intelligent Robotics","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115268975","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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