Pub Date : 2019-11-01DOI: 10.2991/pntim-19.2019.33
Sun Yichao, Shang Yaceng, Lai Hao, Liu Changke
Synchronized dual-frequency induction hardening machine tool is widely used in gear surface heat treatment because of its characters such as saving energy, no pollution in environment, high processing efficiency, small deformation of workpiece and so on. In view of the poor load adaptability of the dual frequency induction heating power supply; the high frequency and intermediate frequency connected to the same transformer, the crosstalk current will bring interference to the stable start of the power supply and so on, the high frequency and intermediate frequency in the synchronous dual frequency topology are modeled and simulated respectively. Based on the resonance points of medium and high frequency circuits, the phase difference angle of the inverting side current is studied at different frequencies, and the effect of crosstalk current is analyzed and verified by experiments. The results show that setting the start-up parameters near the resonance point and setting the phase difference angle threshold can ensure the efficient and stable start-up of dual-frequency power supply. Keywords-Synchronous Dual Frequency; Model Reconstruction; Phase Difference Angle; Crosstalk Current
{"title":"Study on Starting Characteristic of Synchronized Dual Frequency Gear Quenching Power Supply","authors":"Sun Yichao, Shang Yaceng, Lai Hao, Liu Changke","doi":"10.2991/pntim-19.2019.33","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.33","url":null,"abstract":"Synchronized dual-frequency induction hardening machine tool is widely used in gear surface heat treatment because of its characters such as saving energy, no pollution in environment, high processing efficiency, small deformation of workpiece and so on. In view of the poor load adaptability of the dual frequency induction heating power supply; the high frequency and intermediate frequency connected to the same transformer, the crosstalk current will bring interference to the stable start of the power supply and so on, the high frequency and intermediate frequency in the synchronous dual frequency topology are modeled and simulated respectively. Based on the resonance points of medium and high frequency circuits, the phase difference angle of the inverting side current is studied at different frequencies, and the effect of crosstalk current is analyzed and verified by experiments. The results show that setting the start-up parameters near the resonance point and setting the phase difference angle threshold can ensure the efficient and stable start-up of dual-frequency power supply. Keywords-Synchronous Dual Frequency; Model Reconstruction; Phase Difference Angle; Crosstalk Current","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"20 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121800008","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.24
Su-fen Yu, Zhang Leimeng, Tang Bo, Qu Wang
{"title":"A Design of Camera Adjustment Mechanism Based on Automatic Visual NC tool Detector","authors":"Su-fen Yu, Zhang Leimeng, Tang Bo, Qu Wang","doi":"10.2991/pntim-19.2019.24","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.24","url":null,"abstract":"","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124878794","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.52
Zhao Yang, Shen Yunbo, Shang Hanhan, L. Weiwei
The lumped mass model-finite element hybrid model with flexible ring gear is proposed. The dynamic model of planetary transmission system with flexible ring gear structure is established. The calculation of internal meshing time variation between flexible ring gear and planetary gear is proposed. The method of meshing stiffness. According to Newton's second law, the planetary gear train dynamics load model considering time-varying meshing stiffness, damping, comprehensive meshing error and thin-walled sleeve inner ring gear is derived. The planetary gear train with flexible ring gear structure is established. The dynamic equations are solved by numerical methods. The dynamic load-carrying characteristics of the planetary gear trains with different inner sleeves and inner ring gears with different sleeve thicknesses are analyzed. The results show that the inner ring gear sleeve wall The thinner the thickness, the greater the flexibility of the inner ring gear, the smaller the meshing stiffness during internal meshing, the better the load sharing performance of the system, and the internal meshing load factor is more affected. Keywords-Planetary Train; Flexible Ring Gear; Loaded
{"title":"Analysis of the Load Sharing of the Flexible Ring Gear Planetary Gear Train","authors":"Zhao Yang, Shen Yunbo, Shang Hanhan, L. Weiwei","doi":"10.2991/pntim-19.2019.52","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.52","url":null,"abstract":"The lumped mass model-finite element hybrid model with flexible ring gear is proposed. The dynamic model of planetary transmission system with flexible ring gear structure is established. The calculation of internal meshing time variation between flexible ring gear and planetary gear is proposed. The method of meshing stiffness. According to Newton's second law, the planetary gear train dynamics load model considering time-varying meshing stiffness, damping, comprehensive meshing error and thin-walled sleeve inner ring gear is derived. The planetary gear train with flexible ring gear structure is established. The dynamic equations are solved by numerical methods. The dynamic load-carrying characteristics of the planetary gear trains with different inner sleeves and inner ring gears with different sleeve thicknesses are analyzed. The results show that the inner ring gear sleeve wall The thinner the thickness, the greater the flexibility of the inner ring gear, the smaller the meshing stiffness during internal meshing, the better the load sharing performance of the system, and the internal meshing load factor is more affected. Keywords-Planetary Train; Flexible Ring Gear; Loaded","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114888624","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.67
Lei Chao, Wang Changyuan, Lin Zhi, Huang Wenbo
Fatigue driving is the main factor in many traffic accidents. The eye behavior is the main direction in the field of fatigue driving research. It reflects the degree of fatigue of the human brain to some extent. In this paper, the publicized CEW human eye opening and closing data set is used to preprocess the human eye image, and then the preprocessed image is placed in the improved LeNet-5 convolutional neural network. In order to fully extract the human eye features, the network is added. The number of layers, at the same time, to speed up the network convergence speed in order to prevent the gradient from disappearing, the activation function is changed from Tanh to ReLU function. Experiments show that the algorithm has a blink recognition rate of 93.5% in the public CEW dataset, and an accuracy rate of 5.1% compared with the unmodified LeNet-5. This method has a good blink detection effect and has important application value in the field of fatigue driving. Keywords-Fatigue Driving; Blinking Algorithm; Convolutional Neural Network; Network Optimization
{"title":"Blink Fatigue Detection Algorithm Based on Improved Lenet-5","authors":"Lei Chao, Wang Changyuan, Lin Zhi, Huang Wenbo","doi":"10.2991/pntim-19.2019.67","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.67","url":null,"abstract":"Fatigue driving is the main factor in many traffic accidents. The eye behavior is the main direction in the field of fatigue driving research. It reflects the degree of fatigue of the human brain to some extent. In this paper, the publicized CEW human eye opening and closing data set is used to preprocess the human eye image, and then the preprocessed image is placed in the improved LeNet-5 convolutional neural network. In order to fully extract the human eye features, the network is added. The number of layers, at the same time, to speed up the network convergence speed in order to prevent the gradient from disappearing, the activation function is changed from Tanh to ReLU function. Experiments show that the algorithm has a blink recognition rate of 93.5% in the public CEW dataset, and an accuracy rate of 5.1% compared with the unmodified LeNet-5. This method has a good blink detection effect and has important application value in the field of fatigue driving. Keywords-Fatigue Driving; Blinking Algorithm; Convolutional Neural Network; Network Optimization","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116090453","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.37
Z. Peng, Fan Yadong, Liang Xiaowei, Chen Jingwen
How to conduct a wide range of problem analysis on production line work in a short time and standardize, its work has become a major difficulty for enterprises to improve work efficiency. This paper takes M company's Rail car assembly as an example to conduct the job optimization. It uses the kmeans algorithm in machine learning to conduct clustering analysis on job data,Identify common and unusual factors in the assignment. Establishing different text dictionaries aims to normalize the expression of texts and help identify as well as remove non value-added work efficiently. Application of machine learning makes it easy for management personnel to identify the operational bottlenecks of the entire production line, achieve standardized operations, and improve production efficiency. Keywords-K-means Algorithm; Text processing; job standardization; Non-value-added Operations
{"title":"Research on Assembly Line Optimization Based on Machine Learning","authors":"Z. Peng, Fan Yadong, Liang Xiaowei, Chen Jingwen","doi":"10.2991/pntim-19.2019.37","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.37","url":null,"abstract":"How to conduct a wide range of problem analysis on production line work in a short time and standardize, its work has become a major difficulty for enterprises to improve work efficiency. This paper takes M company's Rail car assembly as an example to conduct the job optimization. It uses the kmeans algorithm in machine learning to conduct clustering analysis on job data,Identify common and unusual factors in the assignment. Establishing different text dictionaries aims to normalize the expression of texts and help identify as well as remove non value-added work efficiently. Application of machine learning makes it easy for management personnel to identify the operational bottlenecks of the entire production line, achieve standardized operations, and improve production efficiency. Keywords-K-means Algorithm; Text processing; job standardization; Non-value-added Operations","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115664989","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.44
L. Yang, Shang Yaceng, Lai Hao, Sun Yichao
Dual-frequency induction heating technologyhas significant advantages over traditional single-frequency heating for gear quenching. In this paper, the absorption of gear induction heating energy is analyzed theoretically. Based on the simulation of high frequency, medium frequency and dual-frequency magnetic and thermal field with 2-mode 22tooth gear on ANSYS, it is concluded that the uniformity of the dual-frequency induction heating power supply has obvious advantages in heating. The structure of the dual inverter bridge synchronous dual-frequency induction power supply is studied, the dual inverter bridge synchronous dual-frequency sensor parameters are optimized, and the output variable voltage ratio of 5:1 is determined to achieve the maximum load current inflow to the load. Keywords-Gear Quenching; Induction Heating; Sychronous Dual Frequency; Variable Pressure Ratio
{"title":"Designing and Optimization of Gear Synchronous Dual-Frequency Induction Heating Power Supply Based on ANSYS","authors":"L. Yang, Shang Yaceng, Lai Hao, Sun Yichao","doi":"10.2991/pntim-19.2019.44","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.44","url":null,"abstract":"Dual-frequency induction heating technologyhas significant advantages over traditional single-frequency heating for gear quenching. In this paper, the absorption of gear induction heating energy is analyzed theoretically. Based on the simulation of high frequency, medium frequency and dual-frequency magnetic and thermal field with 2-mode 22tooth gear on ANSYS, it is concluded that the uniformity of the dual-frequency induction heating power supply has obvious advantages in heating. The structure of the dual inverter bridge synchronous dual-frequency induction power supply is studied, the dual inverter bridge synchronous dual-frequency sensor parameters are optimized, and the output variable voltage ratio of 5:1 is determined to achieve the maximum load current inflow to the load. Keywords-Gear Quenching; Induction Heating; Sychronous Dual Frequency; Variable Pressure Ratio","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115115679","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.62
Dongqun Xin, L. HongJun, Yao Lei-jiang, Ding You
Modern structural design achieves a lighter and more efficient structure by mimicking the natural structure of insects, plants and microorganisms. There are many masters in nature, such as nests, spiders, dragonflies, ants, etc. In this paper, the topology optimized by mimicking spiders and bacteria, the load point or structural coordinate point are simulated into scattered random points, then search these points like bacteria looking for food and connect the points together as spiders build nets in the space, and control the topological structures based on parameter control. This bionic topology method can achieve synchronization of structural design and structural optimization. Keywords-Structural Design; Topology; Random Points; Optimization
{"title":"Topological Optimization of Random Distributed Points","authors":"Dongqun Xin, L. HongJun, Yao Lei-jiang, Ding You","doi":"10.2991/pntim-19.2019.62","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.62","url":null,"abstract":"Modern structural design achieves a lighter and more efficient structure by mimicking the natural structure of insects, plants and microorganisms. There are many masters in nature, such as nests, spiders, dragonflies, ants, etc. In this paper, the topology optimized by mimicking spiders and bacteria, the load point or structural coordinate point are simulated into scattered random points, then search these points like bacteria looking for food and connect the points together as spiders build nets in the space, and control the topological structures based on parameter control. This bionic topology method can achieve synchronization of structural design and structural optimization. Keywords-Structural Design; Topology; Random Points; Optimization","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129487421","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}
Wang Hongqiang, Liu Zhihao, Han Quanli, Sun Zhengyang
After the workpiece is processed, the barrel mill is widely used as a burr removal device. Therefore, in order to improve the efficiency of burr removal and enhance the polishing effect on the surface of the workpiece, the conventional roller grinder is improved in design, and the continuous batch grinding method is used instead of the conventional batch grinding method, and the automatic workpiece transfer device is added after the end of the grinding. , thereby increasing the grinding efficiency. Using SolidWorks software, three-dimensional solid modeling and virtual prototype assembly were carried out on the feeding device, grinding device and conveying device. The static analysis of the roller bracket was carried out by ANSYS Workbench software, and the rationality of the design was verified. The results show that the burr removal rate is increased by 10%~20% compared with the traditional grinding machine, and the surface roughness is improved by 1~2, which improves the production efficiency to a certain extent. Keywords-Roller Mill; Burr Removal; Surface Polishing; 3D Solid Modeling; ANSYS Workbench
{"title":"Continuous Feed Roller Grinder Design and Its Finite Element Analysis Based on Solid Works","authors":"Wang Hongqiang, Liu Zhihao, Han Quanli, Sun Zhengyang","doi":"10.2991/pntim-19.2019.5","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.5","url":null,"abstract":"After the workpiece is processed, the barrel mill is widely used as a burr removal device. Therefore, in order to improve the efficiency of burr removal and enhance the polishing effect on the surface of the workpiece, the conventional roller grinder is improved in design, and the continuous batch grinding method is used instead of the conventional batch grinding method, and the automatic workpiece transfer device is added after the end of the grinding. , thereby increasing the grinding efficiency. Using SolidWorks software, three-dimensional solid modeling and virtual prototype assembly were carried out on the feeding device, grinding device and conveying device. The static analysis of the roller bracket was carried out by ANSYS Workbench software, and the rationality of the design was verified. The results show that the burr removal rate is increased by 10%~20% compared with the traditional grinding machine, and the surface roughness is improved by 1~2, which improves the production efficiency to a certain extent. Keywords-Roller Mill; Burr Removal; Surface Polishing; 3D Solid Modeling; ANSYS Workbench","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128234871","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 new 3D printing lamination process to prepare porous ceramics with tight bonding between layers. The ceramic slurry is prepared by mixing alumina powder, organic binder and deionized water, nylon mesh cloth is used as organic template, scraper is used to scrape the ceramic slurry into the organic template, and the organic template layer is dried and laser scanned to obtain a single The green layer is obtained by laminating the layers and then sintering the ceramic body to obtain a porous ceramic. The results show that the compressive strength of porous ceramics prepared by this method can reach 43.12Mpa, the tensile strength between layers can reach 2.2Mpa, the diameter of ceramic through-hole is 70μm. The pore size and pore spacing of the ceramic green body processed by the process can be controlled, and the adhesion of adjacent layers of the ceramic body is improved, thereby improving the compressive strength of the ceramic material. Keywords-Laminate Manufacturing; Organic Template; Porous Ceramic; Material Properties
{"title":"Research on Porous Ceramic 3D Printing Process Based on Laminated Template Method","authors":"Chen Shihao, Chengxu Hua, Zhang Geng, Zhang Qishuai","doi":"10.2991/pntim-19.2019.48","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.48","url":null,"abstract":"This paper proposes a new 3D printing lamination process to prepare porous ceramics with tight bonding between layers. The ceramic slurry is prepared by mixing alumina powder, organic binder and deionized water, nylon mesh cloth is used as organic template, scraper is used to scrape the ceramic slurry into the organic template, and the organic template layer is dried and laser scanned to obtain a single The green layer is obtained by laminating the layers and then sintering the ceramic body to obtain a porous ceramic. The results show that the compressive strength of porous ceramics prepared by this method can reach 43.12Mpa, the tensile strength between layers can reach 2.2Mpa, the diameter of ceramic through-hole is 70μm. The pore size and pore spacing of the ceramic green body processed by the process can be controlled, and the adhesion of adjacent layers of the ceramic body is improved, thereby improving the compressive strength of the ceramic material. Keywords-Laminate Manufacturing; Organic Template; Porous Ceramic; Material Properties","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"23 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125689022","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 : 2019-11-01DOI: 10.2991/pntim-19.2019.18
A. Xin, Duyi Jiang, Bai Yu, L. Hang
{"title":"Research on Knowledge Management of Aviation Manufacturing Industry Based on Association Rules","authors":"A. Xin, Duyi Jiang, Bai Yu, L. Hang","doi":"10.2991/pntim-19.2019.18","DOIUrl":"https://doi.org/10.2991/pntim-19.2019.18","url":null,"abstract":"","PeriodicalId":344913,"journal":{"name":"Proceedings of the 2019 International Conference on Precision Machining, Non-Traditional Machining and Intelligent Manufacturing (PNTIM 2019)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132068680","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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