Pub Date : 2014-12-18DOI: 10.1109/ICCAS.2014.6987818
S. Kubo, A. Sakaguch, T. Takimoto
This paper deals with a flying observation which are consist of a helium gas balloon and a tilt rotor helicopter. The helium gas balloon can make flight for a long time. The tilt rotor helicopter is stable in the wind and increase buoyant force. The observation system with the helium gas balloon and the tilt rotor gets the best of both worlds. In general, helium gas is released from a balloon in every aerial photographing work. Moreover most aerial photographers with the balloon give up a flight in the wind of 5 m/s or greater. However proposed device does not need to release helium gas. Additionally, the flying observation device in the proposed can make a flight in the winds of 5 m/s or greater.
{"title":"Development of flying observation system with helium gas balloon and tilt rotors","authors":"S. Kubo, A. Sakaguch, T. Takimoto","doi":"10.1109/ICCAS.2014.6987818","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987818","url":null,"abstract":"This paper deals with a flying observation which are consist of a helium gas balloon and a tilt rotor helicopter. The helium gas balloon can make flight for a long time. The tilt rotor helicopter is stable in the wind and increase buoyant force. The observation system with the helium gas balloon and the tilt rotor gets the best of both worlds. In general, helium gas is released from a balloon in every aerial photographing work. Moreover most aerial photographers with the balloon give up a flight in the wind of 5 m/s or greater. However proposed device does not need to release helium gas. Additionally, the flying observation device in the proposed can make a flight in the winds of 5 m/s or greater.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"93 1","pages":"1627-1630"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82474512","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6987800
Seungkyu Park, H. Ahn
This paper presents a robust T-S Fuzzy controller with a weighted integral action for Permanent Magnet Synchronous Motor which have nonlinear dynamics. The T-S Fuzzy controller is used for the robustness of nonlinear systems and the weighted integral action is used for the improvement of control performance. A T-S Fuzzy controller is designed by combining the local controllers with the overall stability, and LMI(Linear Matrix Inequality)is used to determine the gains of linear controllers. The control performance of PMSM is changed into regulator problem by introducing the integral action and the weighting factor gives flexibility to a T-S fuzzy controller.
{"title":"Robust T-S Fuzzy H∞ control of interior permanent magnet motor using weighted integral action","authors":"Seungkyu Park, H. Ahn","doi":"10.1109/ICCAS.2014.6987800","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987800","url":null,"abstract":"This paper presents a robust T-S Fuzzy controller with a weighted integral action for Permanent Magnet Synchronous Motor which have nonlinear dynamics. The T-S Fuzzy controller is used for the robustness of nonlinear systems and the weighted integral action is used for the improvement of control performance. A T-S Fuzzy controller is designed by combining the local controllers with the overall stability, and LMI(Linear Matrix Inequality)is used to determine the gains of linear controllers. The control performance of PMSM is changed into regulator problem by introducing the integral action and the weighting factor gives flexibility to a T-S fuzzy controller.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"6 1","pages":"1504-1507"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82499835","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6987786
Ki-Ho Lee, Hyun-Sik Ahn, C. Moon
In this paper, a brushless DC (BLDC) motor control system is implemented to apply to an x-by-wire system based on ISO 26262 which is a functional safety standard for road vehicle. Recently, conventional mechanical and hydraulic systems are replaced by electric/electronic (E/E) systems to enhance the vehicle driving performance and safety. Particularly, because x-by-wire systems have the safety-critical functions, the reliability of the systems is needed to be improved by considering functional safety. For hardware and software requirement considered functional safety, electronic control unit (ECU) of the proposed BLDC motor control system has a microcontroller with an asymmetric dual-core architecture and an external watchdog. Functional safety oriented monitoring functions are implemented by using the ECU design and also verified by using hardware-in-the-loop simulation (HILS). The proposed system is very effective for detecting the software faults and mitigating the influence of the hardware failures with the functional safety compliant ECU.
{"title":"Implementation of approach to functional safety compliant brushless DC motor control system","authors":"Ki-Ho Lee, Hyun-Sik Ahn, C. Moon","doi":"10.1109/ICCAS.2014.6987786","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987786","url":null,"abstract":"In this paper, a brushless DC (BLDC) motor control system is implemented to apply to an x-by-wire system based on ISO 26262 which is a functional safety standard for road vehicle. Recently, conventional mechanical and hydraulic systems are replaced by electric/electronic (E/E) systems to enhance the vehicle driving performance and safety. Particularly, because x-by-wire systems have the safety-critical functions, the reliability of the systems is needed to be improved by considering functional safety. For hardware and software requirement considered functional safety, electronic control unit (ECU) of the proposed BLDC motor control system has a microcontroller with an asymmetric dual-core architecture and an external watchdog. Functional safety oriented monitoring functions are implemented by using the ECU design and also verified by using hardware-in-the-loop simulation (HILS). The proposed system is very effective for detecting the software faults and mitigating the influence of the hardware failures with the functional safety compliant ECU.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"70 1","pages":"1438-1442"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89889840","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 presents a geometric method for solving the inverse and forward kinematics of Delta robot, and then investigated the problem of path tracking control. The forward kinematics is most commonly solved by various iterative methods, which may suffer from slow convergence rate and strict initial value conditions. In this paper, this problem is simplified as solving the intersection point of two circles and then transforming the coordinates system to get the final solution. This method has advantages in its simplicity, accuracy and efficiency. Based on the solution to kinematics and the derivation of Jacobian matrix, the path tracking control is studied from two parts: the superior trajectory planning and the lower control system. Trajectory planning aims to define a temporal motion law along a given geometric path. A method for trajectory planning is presented which is based on a modified trapezoidal velocity profile (TVP) of which initial and final velocities could be nonzero depending on its movement model, whether continuous path (CP) or point to point (PTP). A velocity control method is proposed using a nonlinear PD controller to ensure the end effector tracking the desired path with high precision. At last, a demo trajectory is generated to verify the feasibility of the method experimentally.
{"title":"A geometric method for kinematics of delta robot and its path tracking control","authors":"Xue-Wen Yang, Zuren Feng, Chenyu Liu, Xiaodong Ren","doi":"10.1109/ICCAS.2014.6988043","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6988043","url":null,"abstract":"This paper presents a geometric method for solving the inverse and forward kinematics of Delta robot, and then investigated the problem of path tracking control. The forward kinematics is most commonly solved by various iterative methods, which may suffer from slow convergence rate and strict initial value conditions. In this paper, this problem is simplified as solving the intersection point of two circles and then transforming the coordinates system to get the final solution. This method has advantages in its simplicity, accuracy and efficiency. Based on the solution to kinematics and the derivation of Jacobian matrix, the path tracking control is studied from two parts: the superior trajectory planning and the lower control system. Trajectory planning aims to define a temporal motion law along a given geometric path. A method for trajectory planning is presented which is based on a modified trapezoidal velocity profile (TVP) of which initial and final velocities could be nonzero depending on its movement model, whether continuous path (CP) or point to point (PTP). A velocity control method is proposed using a nonlinear PD controller to ensure the end effector tracking the desired path with high precision. At last, a demo trajectory is generated to verify the feasibility of the method experimentally.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"2 1","pages":"509-514"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90270184","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6988036
Jinho Lee, J. Jo, Youngjae Han, Changyoung Lee
For high speed maglev using ElectroMagnetic Suspension(EMS) as levitation method, the gap between vehicle and guideway surface is maintained by only about 10mm. Therefore, to prevent the contact and improve the ride comfort, the guideway irregularity should be controlled below a certain level. Especially, the LSM stator pack attached under guideway should be clamped without any looseness, otherwise the serious collision would happen. In this study, to monitor the guideway status, an inspection vehicle is proposed and the monitoring algorithms are reviewed.
{"title":"The development and application of guideway monitoring vehicle for super speed maglev","authors":"Jinho Lee, J. Jo, Youngjae Han, Changyoung Lee","doi":"10.1109/ICCAS.2014.6988036","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6988036","url":null,"abstract":"For high speed maglev using ElectroMagnetic Suspension(EMS) as levitation method, the gap between vehicle and guideway surface is maintained by only about 10mm. Therefore, to prevent the contact and improve the ride comfort, the guideway irregularity should be controlled below a certain level. Especially, the LSM stator pack attached under guideway should be clamped without any looseness, otherwise the serious collision would happen. In this study, to monitor the guideway status, an inspection vehicle is proposed and the monitoring algorithms are reviewed.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"21 1","pages":"427-429"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84472415","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6987982
N. S. Ahmad
Frequency-based Popov criterion has been previously used to analyse and design the analog phase-locked loops (PLLs) in the literature. Although in general it is better than the circle criterion for Lur'e systems with sector-bounded nonlinearities, Popov criterion may be conservative when the multiplier is limited to be nonnegative. Furthermore, for high order systems or multi-input-multi-output cases, the frequency-based approach will be computationally intensive. In this paper, a less conservative phaselock condition based on extended Popov criterion where the multiplier is indefinite is presented. The result is formulated in terms of linear matrix inequality which can be easily solved via convex optimization methods. A numerical example with Butterworth filter is provided to show that the result provides a significant improvement for the stability and locking frequency of analog PLLs.
{"title":"A less conservative phaselock criterion with linear matrix inequality condition","authors":"N. S. Ahmad","doi":"10.1109/ICCAS.2014.6987982","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987982","url":null,"abstract":"Frequency-based Popov criterion has been previously used to analyse and design the analog phase-locked loops (PLLs) in the literature. Although in general it is better than the circle criterion for Lur'e systems with sector-bounded nonlinearities, Popov criterion may be conservative when the multiplier is limited to be nonnegative. Furthermore, for high order systems or multi-input-multi-output cases, the frequency-based approach will be computationally intensive. In this paper, a less conservative phaselock condition based on extended Popov criterion where the multiplier is indefinite is presented. The result is formulated in terms of linear matrix inequality which can be easily solved via convex optimization methods. A numerical example with Butterworth filter is provided to show that the result provides a significant improvement for the stability and locking frequency of analog PLLs.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"36 1","pages":"179-183"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84527695","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6987752
H. Osman
This paper presents an evolution algorithm as a powerful optimisation technique for tuning Model Based Predictive Control (MBPC) at the implications of different levels of model uncertainties. Although Standard Genetic Algorithms (SGAs) are proven to successfully tune and optimise MBPC parameters when no model mismatch. SGAs are trapped in a local optimum at the price of model uncertainty. The multi-objective evaluation algorithms are capable to incorporate many objective functions that can meet simultaneously robust control design objective functions. These promising techniques are successfully implemented to stabilised MBPC at high model uncertainty.
{"title":"LQ evolution algorithm optimizer for model predictive control at model uncertainty","authors":"H. Osman","doi":"10.1109/ICCAS.2014.6987752","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987752","url":null,"abstract":"This paper presents an evolution algorithm as a powerful optimisation technique for tuning Model Based Predictive Control (MBPC) at the implications of different levels of model uncertainties. Although Standard Genetic Algorithms (SGAs) are proven to successfully tune and optimise MBPC parameters when no model mismatch. SGAs are trapped in a local optimum at the price of model uncertainty. The multi-objective evaluation algorithms are capable to incorporate many objective functions that can meet simultaneously robust control design objective functions. These promising techniques are successfully implemented to stabilised MBPC at high model uncertainty.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"6 1","pages":"1272-1277"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82647695","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6988051
Zhiqian Liu, Zhiwei Liang
RoboCup Rescue constructs a virtual agent-rescue disaster environment with buildings burning, roads blocked, and civilians in injure. Due to the tricky tasks of building inferno control in this simulation platform, this paper presents a temperature and fire spot prediction model based on the grey system theory. Rather than the previous way that just extinguishing burning buildings, a pre-extinguish method which is much more efficient in the process of controlling fire spreading by handling not-burning buildings is applied here according to the prediction model, in which the building temperature of the next cycle can be estimated so that whether the building is about to catch fire will be foreknown and advanced decisions will be exploited by agents. Experimental results show that this method can achieve an enhanced effect during fire control process of the fire brigade agent in RoboCup Rescue competitions.
{"title":"The temperature prediction model and fire control method in RoboCup Rescue","authors":"Zhiqian Liu, Zhiwei Liang","doi":"10.1109/ICCAS.2014.6988051","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6988051","url":null,"abstract":"RoboCup Rescue constructs a virtual agent-rescue disaster environment with buildings burning, roads blocked, and civilians in injure. Due to the tricky tasks of building inferno control in this simulation platform, this paper presents a temperature and fire spot prediction model based on the grey system theory. Rather than the previous way that just extinguishing burning buildings, a pre-extinguish method which is much more efficient in the process of controlling fire spreading by handling not-burning buildings is applied here according to the prediction model, in which the building temperature of the next cycle can be estimated so that whether the building is about to catch fire will be foreknown and advanced decisions will be exploited by agents. Experimental results show that this method can achieve an enhanced effect during fire control process of the fire brigade agent in RoboCup Rescue competitions.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"31 1","pages":"488-493"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81647935","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6988032
Hong-youn Kim, Hoon Heo, Young-min Yun, Young-Mok Kwon
A Elevator system composed of a permanent magnet linear synchronous motor (PMLSM) as a stator and a magnetic plate as a mover is proposed in this paper. Rather than using a conventional encoder or resolver, position is measured by adopting a vector control method using two Hall sensors for generating a rectangular wave signal. This method estimates the velocity and position of a mover using the quadrature of two hall sensor signals instead of an encoder signal. Vector control of the PMLSM using two Hall sensors for generating a rectangular wave is proved to control the system in a stable and efficient manner through simulations. Hardware experiments reveal that the position control performance is within the range of 30~50μm with an accuracy of 10~20μm, a two-fold improvement over the conventional method. The proposed method exhibits an economical efficiency and practical usefulness. The vector control technique using two Hall sensors can be installed in a narrow place. Accordingly, the proposed method can be implemented in applications where conventional encoders or resolvers cannot operate.
{"title":"Experimental study on elevator using encoderless magnetic motion (ICCAS 2014)","authors":"Hong-youn Kim, Hoon Heo, Young-min Yun, Young-Mok Kwon","doi":"10.1109/ICCAS.2014.6988032","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6988032","url":null,"abstract":"A Elevator system composed of a permanent magnet linear synchronous motor (PMLSM) as a stator and a magnetic plate as a mover is proposed in this paper. Rather than using a conventional encoder or resolver, position is measured by adopting a vector control method using two Hall sensors for generating a rectangular wave signal. This method estimates the velocity and position of a mover using the quadrature of two hall sensor signals instead of an encoder signal. Vector control of the PMLSM using two Hall sensors for generating a rectangular wave is proved to control the system in a stable and efficient manner through simulations. Hardware experiments reveal that the position control performance is within the range of 30~50μm with an accuracy of 10~20μm, a two-fold improvement over the conventional method. The proposed method exhibits an economical efficiency and practical usefulness. The vector control technique using two Hall sensors can be installed in a narrow place. Accordingly, the proposed method can be implemented in applications where conventional encoders or resolvers cannot operate.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"38 1","pages":"443-448"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80334289","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 : 2014-12-18DOI: 10.1109/ICCAS.2014.6987871
Takeharu Hayashi, Yoshihiko Takahashi
We are developing a small compact electric motor tricycle with a low powered battery (7.2 V, approximately 2Ah in total) as the electric power source for shopping purposes. The reduction ratio should be adjusted per the driving situation because of the use of a low powered battery. We designed an actuator system with speed change mechanism for the compact electric motor tricycle. A consumer bicycle is used as the base vehicle, and we focused on the development of an actuator system. A multistep transmission mechanism was designed and fabricated using gears, chains, and sprockets. A 150 W maxon DC motor was used, and the motor speed was controlled using a PWM using MOS-FETs and a PIC microcomputer. Running experiments were conducted to observe the performance of the fabricated vehicle. We confirmed that the fabricated vehicle was able to operate over 30 minutes at a speed of over 3 km/h. Longer running duration must be addressed in future research.
{"title":"Development of small compact electric motor tricycle for shopping","authors":"Takeharu Hayashi, Yoshihiko Takahashi","doi":"10.1109/ICCAS.2014.6987871","DOIUrl":"https://doi.org/10.1109/ICCAS.2014.6987871","url":null,"abstract":"We are developing a small compact electric motor tricycle with a low powered battery (7.2 V, approximately 2Ah in total) as the electric power source for shopping purposes. The reduction ratio should be adjusted per the driving situation because of the use of a low powered battery. We designed an actuator system with speed change mechanism for the compact electric motor tricycle. A consumer bicycle is used as the base vehicle, and we focused on the development of an actuator system. A multistep transmission mechanism was designed and fabricated using gears, chains, and sprockets. A 150 W maxon DC motor was used, and the motor speed was controlled using a PWM using MOS-FETs and a PIC microcomputer. Running experiments were conducted to observe the performance of the fabricated vehicle. We confirmed that the fabricated vehicle was able to operate over 30 minutes at a speed of over 3 km/h. Longer running duration must be addressed in future research.","PeriodicalId":6525,"journal":{"name":"2014 14th International Conference on Control, Automation and Systems (ICCAS 2014)","volume":"6 1","pages":"710-715"},"PeriodicalIF":0.0,"publicationDate":"2014-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85372991","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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