Pub Date : 2010-03-21DOI: 10.1109/AMC.2010.5464083
I. Smadi, H. Omori, Y. Fujimoto
This paper presents a full direct-drive motion of a spiral motor. Spiral motor, is a novel high thrust force actuator with high backdrivability, consists of a spiral structure mover and stator. The mover moves spirally in the stator, and the linear motion is extracted to drive the load. A proper gap control against the load fluctuation is needed to achieve full direct drive motion. In this paper, an exact feedback linearization engaged with DOB is used to achieve independent position/gap control of a spiral motor. Through the use of high gain feedback time scale separation is artificially introduced and the overall closed-loop system is transformed into a singular perturbation one. Then, using tools from singular perturbation theory, the proposed method ensures arbitrary disturbance attenuation, small tracking error, and boundness of all closed loop signals. Finally, simulation results are given to verify the theoretical one.
{"title":"On independent position/gap control of a spiral motor","authors":"I. Smadi, H. Omori, Y. Fujimoto","doi":"10.1109/AMC.2010.5464083","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464083","url":null,"abstract":"This paper presents a full direct-drive motion of a spiral motor. Spiral motor, is a novel high thrust force actuator with high backdrivability, consists of a spiral structure mover and stator. The mover moves spirally in the stator, and the linear motion is extracted to drive the load. A proper gap control against the load fluctuation is needed to achieve full direct drive motion. In this paper, an exact feedback linearization engaged with DOB is used to achieve independent position/gap control of a spiral motor. Through the use of high gain feedback time scale separation is artificially introduced and the overall closed-loop system is transformed into a singular perturbation one. Then, using tools from singular perturbation theory, the proposed method ensures arbitrary disturbance attenuation, small tracking error, and boundness of all closed loop signals. Finally, simulation results are given to verify the theoretical one.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129609512","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464086
Pavel Burget, Pavel Mezera
The model of the juggler is a mechanical machinery designed and constructed to demonstrate and teach control of fast and highly effective servo drives that are commonly used in various motion control applications in industry. The aim of this project is to create a control system able to juggle with three billiard balls, close a visual feedback to recognise actual position of individual balls and present procedures that can be used to design and control similar systems in industrial applications.
{"title":"A visual-feedback juggler with servo drives","authors":"Pavel Burget, Pavel Mezera","doi":"10.1109/AMC.2010.5464086","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464086","url":null,"abstract":"The model of the juggler is a mechanical machinery designed and constructed to demonstrate and teach control of fast and highly effective servo drives that are commonly used in various motion control applications in industry. The aim of this project is to create a control system able to juggle with three billiard balls, close a visual feedback to recognise actual position of individual balls and present procedures that can be used to design and control similar systems in industrial applications.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129473300","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464108
C. Mitsantisuk, K. Ohishi, S. Urushihara, S. Katsura
The development of haptic technology has been a significant trend worldwide. To simulate the virtual environments, several researchers have estimated the parameters of environment in order to interact with human operators. However, the material properties of real environments are greatly influenced by temperature. In this paper, the haptic databased is designed and all of the properties of B-spline curves can be adopted to construct the virtual environments. The order of the curve for the B-spline blending function is set as the natural cubic B-spline. Thus, it is possible to generate a good realization of interaction force and simulate a soft and hard virtual environment according to the material properties. From the experimental results, the proposed mathematical model can be changed the material properties under various condition of temperature.
{"title":"Stiffness modeling across transition temperatures in virtual environments by B-spline interpolation","authors":"C. Mitsantisuk, K. Ohishi, S. Urushihara, S. Katsura","doi":"10.1109/AMC.2010.5464108","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464108","url":null,"abstract":"The development of haptic technology has been a significant trend worldwide. To simulate the virtual environments, several researchers have estimated the parameters of environment in order to interact with human operators. However, the material properties of real environments are greatly influenced by temperature. In this paper, the haptic databased is designed and all of the properties of B-spline curves can be adopted to construct the virtual environments. The order of the curve for the B-spline blending function is set as the natural cubic B-spline. Thus, it is possible to generate a good realization of interaction force and simulate a soft and hard virtual environment according to the material properties. From the experimental results, the proposed mathematical model can be changed the material properties under various condition of temperature.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129237415","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464019
Chun-Ming Wen, M. Cheng, Ke-Han Su
In industrial precision applications using dual-axis micro-positioning stages powered by piezoelectric actuators (PEA), the trajectory tracking and contour following performances are limited due to PEA's inherent hysteretic nonlinearity and time varying parameters. In order to cope with this problem, a position control scheme based on reinforcement learning cerebellar model articulation controller (RLCMAC) is developed in this paper. In the proposed control scheme, for each individual-axis, a CMAC-based feedforward controller with reinforcement learning scheme and a conventional proportionalintegral (PI) feedback controller are used. Moreover, in order to reduce contour errors, a CMAC-based cross-coupled controller (CMAC-CCC) is applied to improve the contouring accuracy of a dual-axis micro-positioning stage. Finally, an integrated control scheme is proposed to improve the tracking and contouring accuracy. Experimental results verify the effectiveness of the proposed approach.
{"title":"Contouring accuracy improvement of a dual-axis micro-positioning stage powered by piezoelectric actuator","authors":"Chun-Ming Wen, M. Cheng, Ke-Han Su","doi":"10.1109/AMC.2010.5464019","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464019","url":null,"abstract":"In industrial precision applications using dual-axis micro-positioning stages powered by piezoelectric actuators (PEA), the trajectory tracking and contour following performances are limited due to PEA's inherent hysteretic nonlinearity and time varying parameters. In order to cope with this problem, a position control scheme based on reinforcement learning cerebellar model articulation controller (RLCMAC) is developed in this paper. In the proposed control scheme, for each individual-axis, a CMAC-based feedforward controller with reinforcement learning scheme and a conventional proportionalintegral (PI) feedback controller are used. Moreover, in order to reduce contour errors, a CMAC-based cross-coupled controller (CMAC-CCC) is applied to improve the contouring accuracy of a dual-axis micro-positioning stage. Finally, an integrated control scheme is proposed to improve the tracking and contouring accuracy. Experimental results verify the effectiveness of the proposed approach.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124332828","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464008
H. Takimoto, S. Yoshimori, Y. Mitsukura, M. Fukumi
In the print-type steganographk system and watermark, a calibration pattern is arranged around contents where invisible data is embedded, as plural feature points between an original image and the scanned image for normalization of the scanned image. However, it is clear that conventional methods interfere with page layout and artwork of contents. In addition, visible calibration patterns are not suitable for security service. In this paper, we propose an arrangement and detection method of an invisible calibration pattern based on human visual perception. We embed the calibration pattern in an original image by adding high frequency component to blue intensity in a limited region. Moreover, the proposed calibration pattern protects page layout and artwork.
{"title":"Invisible calibration pattern based on human visual perception","authors":"H. Takimoto, S. Yoshimori, Y. Mitsukura, M. Fukumi","doi":"10.1109/AMC.2010.5464008","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464008","url":null,"abstract":"In the print-type steganographk system and watermark, a calibration pattern is arranged around contents where invisible data is embedded, as plural feature points between an original image and the scanned image for normalization of the scanned image. However, it is clear that conventional methods interfere with page layout and artwork of contents. In addition, visible calibration patterns are not suitable for security service. In this paper, we propose an arrangement and detection method of an invisible calibration pattern based on human visual perception. We embed the calibration pattern in an original image by adding high frequency component to blue intensity in a limited region. Moreover, the proposed calibration pattern protects page layout and artwork.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124341759","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464056
Y. Uenaka, M. Sazawa, K. Ohishi
It is very important to identify the electrical parameters accurately for the servo system of PM motor, that keep the fine torque response and the fine speed response. Generally, the electrical parameters of PM motor are identified by using the motor voltage and motor current. However, current sensor often has the offset value. In this case, the servo system of PM motor has the torque ripple and can not be identified accurately the motor parameters. In order to overcome these problems, this paper proposes a new self-tuning control of both current sensor offset and electrical parameter variation for PM motor. In this paper, the experimental results and the numerical simulation resluts confirm that the proposed method well estimates each current sensor offset of U phase and V phase, the motor resistance Ra, the motor inductance La and the motor magnetic flux Φfa individually and accurately, and carries out the fine self-tuning for the current controller of PM motor servo system.
{"title":"Self-tuning control of both current sensor offset and electrical parameter variations for PM motor","authors":"Y. Uenaka, M. Sazawa, K. Ohishi","doi":"10.1109/AMC.2010.5464056","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464056","url":null,"abstract":"It is very important to identify the electrical parameters accurately for the servo system of PM motor, that keep the fine torque response and the fine speed response. Generally, the electrical parameters of PM motor are identified by using the motor voltage and motor current. However, current sensor often has the offset value. In this case, the servo system of PM motor has the torque ripple and can not be identified accurately the motor parameters. In order to overcome these problems, this paper proposes a new self-tuning control of both current sensor offset and electrical parameter variation for PM motor. In this paper, the experimental results and the numerical simulation resluts confirm that the proposed method well estimates each current sensor offset of U phase and V phase, the motor resistance Ra, the motor inductance La and the motor magnetic flux Φfa individually and accurately, and carries out the fine self-tuning for the current controller of PM motor servo system.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124436952","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464061
M. Nakazato, K. Ohnishi
When a walking trajectory of a 3-dimensional (3D) biped robot is changed, it is necessary to consider not only a sagittal trajectory but also a frontal trajectory. In this paper, an online stride changing method and a walking cycle changing method of biped robots using linear pendulum mode are proposed. With these methods, the trajectory planning is easier than that with some conventional methods because switching from a trajectory of single support phase to a trajectory of double support phase is unnecessary. Moreover, the moving range of center of gravity (COG) is decided arbitrarily. The validity of the proposed methods is confirmed by simulations and experiments.
{"title":"Stride and walking-cycle online changing for biped robot in frontal plane","authors":"M. Nakazato, K. Ohnishi","doi":"10.1109/AMC.2010.5464061","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464061","url":null,"abstract":"When a walking trajectory of a 3-dimensional (3D) biped robot is changed, it is necessary to consider not only a sagittal trajectory but also a frontal trajectory. In this paper, an online stride changing method and a walking cycle changing method of biped robots using linear pendulum mode are proposed. With these methods, the trajectory planning is easier than that with some conventional methods because switching from a trajectory of single support phase to a trajectory of double support phase is unnecessary. Moreover, the moving range of center of gravity (COG) is decided arbitrarily. The validity of the proposed methods is confirmed by simulations and experiments.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124106494","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464029
K. Sonoda, A. Shimada
This paper introduces a sensor-less grasping control technique on two-finger robot hands with visual feedback control. A great number of robot hands have been developed and most of the hands mount many kind of sensors, such as rotary encoders, tactile sensors, and force sensors. However, use of the many sensors increase the cost of robot hands and decrease the reliance. On the other hand, when we observe and assemble some object carefully, we gaze at it but not watch our fingers. Thenfore, as an analogy, robot hands for observationa or assembling may not always need the jount angle sennsors if the system has some vision sensor. Meanwhile, Shimada et.al. have presented an unique sensorless control technique for electric motor driven mechanical systems. It is useful and easy to install but it has been developed only for single digree of freedom systems. Then, we try to extend the sensorless control technique to practical multi-finger robot hand systems with some vision systems. This paper describes the basic technique and show some simulation results for evaluation of validity.
{"title":"A joint angle sensorless grasping control on two-fingered robot hands","authors":"K. Sonoda, A. Shimada","doi":"10.1109/AMC.2010.5464029","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464029","url":null,"abstract":"This paper introduces a sensor-less grasping control technique on two-finger robot hands with visual feedback control. A great number of robot hands have been developed and most of the hands mount many kind of sensors, such as rotary encoders, tactile sensors, and force sensors. However, use of the many sensors increase the cost of robot hands and decrease the reliance. On the other hand, when we observe and assemble some object carefully, we gaze at it but not watch our fingers. Thenfore, as an analogy, robot hands for observationa or assembling may not always need the jount angle sennsors if the system has some vision sensor. Meanwhile, Shimada et.al. have presented an unique sensorless control technique for electric motor driven mechanical systems. It is useful and easy to install but it has been developed only for single digree of freedom systems. Then, we try to extend the sensorless control technique to practical multi-finger robot hand systems with some vision systems. This paper describes the basic technique and show some simulation results for evaluation of validity.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115815292","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 : 2010-03-21DOI: 10.1109/AMC.2010.5464026
B. Yao, Changhu Jiang
The ever increasingly stringent performance requirements of modern mechanical systems have forced control engineers to look beyond traditional linear control theory for more advanced nonlinear controllers. During the past decade, a mathematically rigorous nonlinear adaptive robust control (ARC) theory has been developed and has been experimentally demonstrated achieving significant performance improvement in a number of motion control applications. This plenary paper first uses a simple motion control problem as an example to bring out the conceptual connection and nonlinear extension of the widely used PID controller structure to the developed ARC approach. Through this example, some of the key underlying working mechanisms of the ARC theory can be grasped easily. The paper then highlights how major issues in the precision motion control can be handled systematically and effectively with the ARC framework. The issues considered include (i) large variations of physical parameters of a system; (ii) unknown nonlinearities such as cogging and ripple forces of linear motors; (iii) dynamic uncertain nonlinearities with non-uniformly detectable unmeasured internal states (e.g., friction described by dynamic models in high precision motion controls); and (iv) control input saturation due to limited capacity of physical actuators. The precision motion control of a linear motor driven high-speed/high-acceleration industrial gantry is used as a case study and comparative experimental results are presented to illustrate the achievable performance and limitations of various ARC controllers in implementation.
{"title":"Advanced motion control: From classical PID to nonlinear adaptive robust control","authors":"B. Yao, Changhu Jiang","doi":"10.1109/AMC.2010.5464026","DOIUrl":"https://doi.org/10.1109/AMC.2010.5464026","url":null,"abstract":"The ever increasingly stringent performance requirements of modern mechanical systems have forced control engineers to look beyond traditional linear control theory for more advanced nonlinear controllers. During the past decade, a mathematically rigorous nonlinear adaptive robust control (ARC) theory has been developed and has been experimentally demonstrated achieving significant performance improvement in a number of motion control applications. This plenary paper first uses a simple motion control problem as an example to bring out the conceptual connection and nonlinear extension of the widely used PID controller structure to the developed ARC approach. Through this example, some of the key underlying working mechanisms of the ARC theory can be grasped easily. The paper then highlights how major issues in the precision motion control can be handled systematically and effectively with the ARC framework. The issues considered include (i) large variations of physical parameters of a system; (ii) unknown nonlinearities such as cogging and ripple forces of linear motors; (iii) dynamic uncertain nonlinearities with non-uniformly detectable unmeasured internal states (e.g., friction described by dynamic models in high precision motion controls); and (iv) control input saturation due to limited capacity of physical actuators. The precision motion control of a linear motor driven high-speed/high-acceleration industrial gantry is used as a case study and comparative experimental results are presented to illustrate the achievable performance and limitations of various ARC controllers in implementation.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130916750","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 : 2010-03-21DOI: 10.1109/AMC.2010.5463994
Masahide Ito, M. Shibata
In this paper, we propose a visual tracking control method of a hand-eye robot for a moving target object with multiple feature points. The hand-eye robot is constructed from a three-DoF planar manipulator and a single CCD camera that is mounted on the manipulator's end-effector. The control objective is to keep all feature points of the target object around their desired coordinates on the image plane. In many conventional visual servo methods, it is assumed that the target object is static. Consequently, the visual tracking error arises in the case of a moving target object. Although we have already proposed the visual tracking control systems in consideration of the target object motion, this method can deal only with a single feature point. Therefore, this paper extends such a visual tracking control method to multiple feature points. The validity of our control method is evaluated by an experiment.
{"title":"Visual tracking of hand-eye robot for moving target object with multiple feature points","authors":"Masahide Ito, M. Shibata","doi":"10.1109/AMC.2010.5463994","DOIUrl":"https://doi.org/10.1109/AMC.2010.5463994","url":null,"abstract":"In this paper, we propose a visual tracking control method of a hand-eye robot for a moving target object with multiple feature points. The hand-eye robot is constructed from a three-DoF planar manipulator and a single CCD camera that is mounted on the manipulator's end-effector. The control objective is to keep all feature points of the target object around their desired coordinates on the image plane. In many conventional visual servo methods, it is assumed that the target object is static. Consequently, the visual tracking error arises in the case of a moving target object. Although we have already proposed the visual tracking control systems in consideration of the target object motion, this method can deal only with a single feature point. Therefore, this paper extends such a visual tracking control method to multiple feature points. The validity of our control method is evaluated by an experiment.","PeriodicalId":406900,"journal":{"name":"2010 11th IEEE International Workshop on Advanced Motion Control (AMC)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115995221","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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