Pub Date : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268362
T. Mase, R. Kitahata, T. Hirogaki, E. Aoyama
With the advancement of the motion control of industrial robots in recent years, there is a demand for a method that can easily measure the accuracy of the synchronous control of a 2-axis dual-arm robot. Therefore, in this study, we propose a new measurement method that creates a ball rolling motion in a circular orbit on the work plate and uses the rolling motion error with respect to the reference circle. In this study, we conducted experiments on the teaching method when controlling the rolling motion of the ball at a position away from the center of the robot on the work plate. Results showed that an error occurred in the maximum inclination angle of the plate, which we kept the ball steady by correcting a teaching program. As the load is applied to the wrist joints by the plate, the effect of the correction of the teaching point angle cannot be obtained. However, the method of correcting the angular velocity between the teaching points was found to be effective.
{"title":"Investigation of novel teaching method for skillful operation of working plate with an industrial dual arm robot","authors":"T. Mase, R. Kitahata, T. Hirogaki, E. Aoyama","doi":"10.23919/ICCAS50221.2020.9268362","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268362","url":null,"abstract":"With the advancement of the motion control of industrial robots in recent years, there is a demand for a method that can easily measure the accuracy of the synchronous control of a 2-axis dual-arm robot. Therefore, in this study, we propose a new measurement method that creates a ball rolling motion in a circular orbit on the work plate and uses the rolling motion error with respect to the reference circle. In this study, we conducted experiments on the teaching method when controlling the rolling motion of the ball at a position away from the center of the robot on the work plate. Results showed that an error occurred in the maximum inclination angle of the plate, which we kept the ball steady by correcting a teaching program. As the load is applied to the wrist joints by the plate, the effect of the correction of the teaching point angle cannot be obtained. However, the method of correcting the angular velocity between the teaching points was found to be effective.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"17 1","pages":"1099-1104"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81704115","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268412
Ruisen Huang, Dalin Yang, Kunqiang Qing, K. Hong
One of the advantages of fNIRS systems is their portability for real-world applications. Therefore, the online rejection of the motion artifacts in functional near-infrared spectroscopy (fNIRS) signals is one of the essential research topics. We proposed a square-root cubature Kalman filter using a weighted moving average model to tract the dynamics of motion artifacts. The rationale and feasibility of the method were discussed using simulated data generated using a Balloon model. The results show that the proposed filter has a good suppression of spike-like motion artifacts. Finally, conclusions and further study are discussed.
{"title":"Online Motion-Artifact Removal in fNIRS Signals: Combined Square-Root Cubature Kalman Filter and Weighted Moving Average Model Approach","authors":"Ruisen Huang, Dalin Yang, Kunqiang Qing, K. Hong","doi":"10.23919/ICCAS50221.2020.9268412","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268412","url":null,"abstract":"One of the advantages of fNIRS systems is their portability for real-world applications. Therefore, the online rejection of the motion artifacts in functional near-infrared spectroscopy (fNIRS) signals is one of the essential research topics. We proposed a square-root cubature Kalman filter using a weighted moving average model to tract the dynamics of motion artifacts. The rationale and feasibility of the method were discussed using simulated data generated using a Balloon model. The results show that the proposed filter has a good suppression of spike-like motion artifacts. Finally, conclusions and further study are discussed.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"211 1","pages":"658-663"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79401780","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268306
P. Hušek, J. Stecha
Kalman filter became a popular tool for state estimation of linear dynamical systems especially due to its simplicity. However in the case of nonlinear systems its realization is more complicated. Commonly used approach called Extended Kalman filter consists in local approximation based on linearization. Another possibility is to approximate the corresponding integrals using some feasible procedures. In this paper we apply Gauss-Hermite Quadrature for state estimation of nonlinear systems and compare its accuracy with Extended Kalman filter.
{"title":"Nonlinear Kalman Filter by Hermite-Gauss Quadrature","authors":"P. Hušek, J. Stecha","doi":"10.23919/ICCAS50221.2020.9268306","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268306","url":null,"abstract":"Kalman filter became a popular tool for state estimation of linear dynamical systems especially due to its simplicity. However in the case of nonlinear systems its realization is more complicated. Commonly used approach called Extended Kalman filter consists in local approximation based on linearization. Another possibility is to approximate the corresponding integrals using some feasible procedures. In this paper we apply Gauss-Hermite Quadrature for state estimation of nonlinear systems and compare its accuracy with Extended Kalman filter.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"47 1","pages":"637-642"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78631022","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268205
B. Darmawan, Sang Bong Lee, Gwangjun Go, Chang-sei Kim, Doyeon Bang, Jong-Oh Park, Eunpyo Choi
Microrobots have been demonstrated to have the potential in medical approaches, such as for targeted drug delivery. However, real-time tracking and imaging are still one of the major issues faced by microrobots. Here, we fabricated helical microrobots based on self-folding technique, and we performed double coating of gold nanoparticles (AuNPs) to the surface of microrobots to enhance the image quality under X-ray. The result shows that, we successfully coated the AuNPs into the self-rolled microrobots, and it increases the image quality when compared to non-coated microrobots. Despite the fact that there still remain some challenges to achieve successful applications of microrobots, we believe that the potential of this study can contribute to reduce the challenges faces in the medical microrobot fields.
{"title":"Gold Nanoparticles Embedded Microrobots for Real-time X-ray Imaging","authors":"B. Darmawan, Sang Bong Lee, Gwangjun Go, Chang-sei Kim, Doyeon Bang, Jong-Oh Park, Eunpyo Choi","doi":"10.23919/ICCAS50221.2020.9268205","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268205","url":null,"abstract":"Microrobots have been demonstrated to have the potential in medical approaches, such as for targeted drug delivery. However, real-time tracking and imaging are still one of the major issues faced by microrobots. Here, we fabricated helical microrobots based on self-folding technique, and we performed double coating of gold nanoparticles (AuNPs) to the surface of microrobots to enhance the image quality under X-ray. The result shows that, we successfully coated the AuNPs into the self-rolled microrobots, and it increases the image quality when compared to non-coated microrobots. Despite the fact that there still remain some challenges to achieve successful applications of microrobots, we believe that the potential of this study can contribute to reduce the challenges faces in the medical microrobot fields.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"63 1","pages":"302-305"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79228433","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268298
Seon-il Lee, Hyeon Kim, Uikyum Kim, Hyeonbeom Lee
This paper presents a control algorithm of a contact-based inspection for an Unmanned Aerial Vehicle (UAV) manipulator without using a force sensor. The conventional contact-based operation methods for a ground-based manipulator require a force sensor, but the force measurement is noisy on uneven surfaces. The noisy measurement can cause an unstable flight of the UAV when using direct force measurement as an input. To resolve this issue, we design a contact-force estimation algorithm of a UAV and desired trajectory generation algorithm. Contact-force is estimated by using the dynamics of a UAV and IMU sensor. In addition, to track the concave wall safely, we propose a heading-angle alignment algorithm. Through the Gazebo simulation, we show that the proposed method is effective compared to the force-sensor-based existing method.
{"title":"Concave Wall Surface Tracking for Aerial Manipulator Using Contact Force Estimation Algorithm","authors":"Seon-il Lee, Hyeon Kim, Uikyum Kim, Hyeonbeom Lee","doi":"10.23919/ICCAS50221.2020.9268298","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268298","url":null,"abstract":"This paper presents a control algorithm of a contact-based inspection for an Unmanned Aerial Vehicle (UAV) manipulator without using a force sensor. The conventional contact-based operation methods for a ground-based manipulator require a force sensor, but the force measurement is noisy on uneven surfaces. The noisy measurement can cause an unstable flight of the UAV when using direct force measurement as an input. To resolve this issue, we design a contact-force estimation algorithm of a UAV and desired trajectory generation algorithm. Contact-force is estimated by using the dynamics of a UAV and IMU sensor. In addition, to track the concave wall safely, we propose a heading-angle alignment algorithm. Through the Gazebo simulation, we show that the proposed method is effective compared to the force-sensor-based existing method.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"14 1","pages":"850-855"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85014194","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268366
Tomoya Ono, Soshi Akasaka, Hiroki Ohara, T. Kanamaru
Recently, ICT equipment has been introduced to classrooms in Japan. Moreover, effectiveness of active learning that engages students as active participants in their learning has been discussed. In order to merge the usefulness of ICT and the effectiveness of active learning, we developed interactive floor interface (IFI) that enables users to see teaching materials displayed on a floor and to control it with their gestures. We also developed an interactive teaching material of wave interference designed for IFI. To confirm the effectiveness of IFI, we gave examinations before and after learning to two groups each of which learns wave interference by using either a usual textbook or IFI. As a result, it was found that average scores of examinations have significantly increased in both groups. Although an average increase of scores for IFI was higher than that of usual textbook, we could not show its significant difference. It is important to improve teaching materials for IFI by giving further interactivity, user-friendliness, and so on.
{"title":"Developing Education Support System using Interactive Floor Interface","authors":"Tomoya Ono, Soshi Akasaka, Hiroki Ohara, T. Kanamaru","doi":"10.23919/ICCAS50221.2020.9268366","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268366","url":null,"abstract":"Recently, ICT equipment has been introduced to classrooms in Japan. Moreover, effectiveness of active learning that engages students as active participants in their learning has been discussed. In order to merge the usefulness of ICT and the effectiveness of active learning, we developed interactive floor interface (IFI) that enables users to see teaching materials displayed on a floor and to control it with their gestures. We also developed an interactive teaching material of wave interference designed for IFI. To confirm the effectiveness of IFI, we gave examinations before and after learning to two groups each of which learns wave interference by using either a usual textbook or IFI. As a result, it was found that average scores of examinations have significantly increased in both groups. Although an average increase of scores for IFI was higher than that of usual textbook, we could not show its significant difference. It is important to improve teaching materials for IFI by giving further interactivity, user-friendliness, and so on.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"98 1","pages":"141-144"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85801655","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268255
Jeonghyeon Kim, Sangwon Choi, Jaekuk Choi, Dongsun Lim, Jong-Hyun Kim
In this paper, we introduce a contact type thread tester which can automatically sort out bad thread holes. The existing non-contact type testers used eddy current, camera, ultrasonic, etc. However, non-contact type testers are vulnerable to noise. In this paper, a contact type inspection method is used to sort out the defects of the thread by measuring the reverse torque that occurs while tightening the bolt and threaded holes. This tester is insensitive to noise, such as vibration. We can inspect a thread hole regardless of the size of the hole. Also, the tester automatically aligns bolt and thread hole positions in order to remove the positional error. The tester checks the size of the thread hole using a camera, and automatically carries out the inspection with the optimum torque associated to the hole size. In addition, we develop a smartphone application to control the tester remotely.
{"title":"Contact Type Thread Tester for Tap Inspection Automation","authors":"Jeonghyeon Kim, Sangwon Choi, Jaekuk Choi, Dongsun Lim, Jong-Hyun Kim","doi":"10.23919/ICCAS50221.2020.9268255","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268255","url":null,"abstract":"In this paper, we introduce a contact type thread tester which can automatically sort out bad thread holes. The existing non-contact type testers used eddy current, camera, ultrasonic, etc. However, non-contact type testers are vulnerable to noise. In this paper, a contact type inspection method is used to sort out the defects of the thread by measuring the reverse torque that occurs while tightening the bolt and threaded holes. This tester is insensitive to noise, such as vibration. We can inspect a thread hole regardless of the size of the hole. Also, the tester automatically aligns bolt and thread hole positions in order to remove the positional error. The tester checks the size of the thread hole using a camera, and automatically carries out the inspection with the optimum torque associated to the hole size. In addition, we develop a smartphone application to control the tester remotely.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"1 1","pages":"457-462"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91121783","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268380
Pengfei Lin, Woo Young Choi, Seung-Hi Lee, C. Chung
In this paper, we propose a vehicle lane change system using model predictive path planning (MPPP) based on the artificial potential field (APF) for speeding vehicles. It is shown that APF has high performance in real-time obstacle avoidance. However, it remains unpractical for self-driving cars because the point model used for the APF ignores the lateral vehicle dynamics for the lane-keeping system. To resolve the problem, this paper introduces a novel curve-fitting method combined with the APF applied to plan a drivable path for autonomous vehicles in the lane change action. The proposed system was validated through MATLAB/Simulink with the empirical kinematic model. The simulation results indicate that the model predictive path planning algorithm is highly effective in high-speed lane change scenarios to avoid dynamic obstacle vehicles.
{"title":"Model Predictive Path Planning Based on Artificial Potential Field and Its Application to Autonomous Lane Change","authors":"Pengfei Lin, Woo Young Choi, Seung-Hi Lee, C. Chung","doi":"10.23919/ICCAS50221.2020.9268380","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268380","url":null,"abstract":"In this paper, we propose a vehicle lane change system using model predictive path planning (MPPP) based on the artificial potential field (APF) for speeding vehicles. It is shown that APF has high performance in real-time obstacle avoidance. However, it remains unpractical for self-driving cars because the point model used for the APF ignores the lateral vehicle dynamics for the lane-keeping system. To resolve the problem, this paper introduces a novel curve-fitting method combined with the APF applied to plan a drivable path for autonomous vehicles in the lane change action. The proposed system was validated through MATLAB/Simulink with the empirical kinematic model. The simulation results indicate that the model predictive path planning algorithm is highly effective in high-speed lane change scenarios to avoid dynamic obstacle vehicles.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"71 1","pages":"731-736"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90354244","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268377
Sangyul Park, Hasun Lee, Dongjun Lee
We propose CPG (central pattern generator) based robot control framework constructed based on: 1) the inverse model of the CPG that directly encodes resultant body motion of the robot in CPG parameters; and 2) the CPG parameter adaptation law that enforces robustness of the controller. These two components behaves as feedforward and feedback control for the CPG controlled robot, enabling us to achieve fast and robust generation of a desired body motion for robotic systems operated within complex environmental interaction. The inverse CPG model is constructed based on neural network along with autoencoder to efficiently deal with the dimension decrease from input to output of the model. Also, the CPG parameter adaptation is done with a concept of backpropagation, which is enabled by the adoption of smooth activation function for the inverse CPG model. For the development and verification of the proposed framework, simulation is conducted with two robotic systems, snake-like robot and pivotboard system.
{"title":"Robust Motion Control of Robotic Systems with Environmental Interaction via Data-Driven Inversion of CPG","authors":"Sangyul Park, Hasun Lee, Dongjun Lee","doi":"10.23919/ICCAS50221.2020.9268377","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268377","url":null,"abstract":"We propose CPG (central pattern generator) based robot control framework constructed based on: 1) the inverse model of the CPG that directly encodes resultant body motion of the robot in CPG parameters; and 2) the CPG parameter adaptation law that enforces robustness of the controller. These two components behaves as feedforward and feedback control for the CPG controlled robot, enabling us to achieve fast and robust generation of a desired body motion for robotic systems operated within complex environmental interaction. The inverse CPG model is constructed based on neural network along with autoencoder to efficiently deal with the dimension decrease from input to output of the model. Also, the CPG parameter adaptation is done with a concept of backpropagation, which is enabled by the adoption of smooth activation function for the inverse CPG model. For the development and verification of the proposed framework, simulation is conducted with two robotic systems, snake-like robot and pivotboard system.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"25 1","pages":"692-698"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90416982","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 : 2020-10-13DOI: 10.23919/ICCAS50221.2020.9268424
Jin Ho Yang, Dae Jung Kim, C. Chung
This study aims to propose how autonomous vehicle overtakes an obstacle with model predictive control and makes a lateral ride comfortability by optimizing a jerk in a lateral direction. In this paper, we conducted a case study on collision avoidance in a waypoint tracking situation. To avoid the obstacle, we proposed a desired lateral offset from the global route and used the offset as a reference for avoidance. Then, we defined a quadratic cost function considering the jerk to minimize a motion sickness during the avoidance maneuver. To verify the method, we executed a computational simulation using actual waypoint data. As a result, we observed that the proposed scheme has more comfortability for obstacle avoidance than the method without optimizing the jerk.
{"title":"Predictive Collision Avoidance Control with Optimized Ride Comfort in Vehicle Lateral Motion Control","authors":"Jin Ho Yang, Dae Jung Kim, C. Chung","doi":"10.23919/ICCAS50221.2020.9268424","DOIUrl":"https://doi.org/10.23919/ICCAS50221.2020.9268424","url":null,"abstract":"This study aims to propose how autonomous vehicle overtakes an obstacle with model predictive control and makes a lateral ride comfortability by optimizing a jerk in a lateral direction. In this paper, we conducted a case study on collision avoidance in a waypoint tracking situation. To avoid the obstacle, we proposed a desired lateral offset from the global route and used the offset as a reference for avoidance. Then, we defined a quadratic cost function considering the jerk to minimize a motion sickness during the avoidance maneuver. To verify the method, we executed a computational simulation using actual waypoint data. As a result, we observed that the proposed scheme has more comfortability for obstacle avoidance than the method without optimizing the jerk.","PeriodicalId":6732,"journal":{"name":"2020 20th International Conference on Control, Automation and Systems (ICCAS)","volume":"178 1","pages":"737-742"},"PeriodicalIF":0.0,"publicationDate":"2020-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90441628","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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