Pub Date : 2004-12-01DOI: 10.1109/RAMECH.2004.1438976
Liang Yan, K. Chee, I. Chen, Guilin Yang, Wei Lin
A new form of 3-DOF spherical actuator having a rotor mounted with rare-earth-magnet poles is developed. Since the air-core coils are used in this actuator, the magnetic flux distribution is different from that of conventional electromagnetic devices. In this paper, the solution of the Laplace equation is used to derive the general form of the magnetic field, and a curve fitting approach is proposed to obtain the mathematical expression of the magnetic field. This mathematical representation of the 3D magnetic field can be applied to the torque modelling of the 3-DOF spherical actuator. Experimental studies have been conducted to determine the critical parameters and verify the effectiveness of the proposed approach.
{"title":"A hybrid approach for magnetic field analysis","authors":"Liang Yan, K. Chee, I. Chen, Guilin Yang, Wei Lin","doi":"10.1109/RAMECH.2004.1438976","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438976","url":null,"abstract":"A new form of 3-DOF spherical actuator having a rotor mounted with rare-earth-magnet poles is developed. Since the air-core coils are used in this actuator, the magnetic flux distribution is different from that of conventional electromagnetic devices. In this paper, the solution of the Laplace equation is used to derive the general form of the magnetic field, and a curve fitting approach is proposed to obtain the mathematical expression of the magnetic field. This mathematical representation of the 3D magnetic field can be applied to the torque modelling of the 3-DOF spherical actuator. Experimental studies have been conducted to determine the critical parameters and verify the effectiveness of the proposed approach.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"437 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122881768","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438085
Wang Wei, Liu Zongyu, X. Rongrong
The GPS/INS integration system has been widely applied for navigation due to its complementary characteristics. The tightly coupled integration approach has the advantage over the loosely coupled approach by using raw GPS measurements, but hence introduces nonlinearity into the measurement equation of the Kalman filter. So, linearization is usually used. Consequently, the errors of linearization may make the Kalman filter unstable or even divergent, especially under the situation that low quality inertial devices are included. To solve this problem, an improved tightly coupled approach by adding second-order derivative information to retain some nonlinear characteristics is proposed in this paper. Simulation results indicate that the nonlinear terms included in the filtering process greatly influence the performance of integration, especially in the case where the low quality INS is used in the integrated system.
{"title":"An improved tightly coupled approach for GPS/INS integration","authors":"Wang Wei, Liu Zongyu, X. Rongrong","doi":"10.1109/RAMECH.2004.1438085","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438085","url":null,"abstract":"The GPS/INS integration system has been widely applied for navigation due to its complementary characteristics. The tightly coupled integration approach has the advantage over the loosely coupled approach by using raw GPS measurements, but hence introduces nonlinearity into the measurement equation of the Kalman filter. So, linearization is usually used. Consequently, the errors of linearization may make the Kalman filter unstable or even divergent, especially under the situation that low quality inertial devices are included. To solve this problem, an improved tightly coupled approach by adding second-order derivative information to retain some nonlinear characteristics is proposed in this paper. Simulation results indicate that the nonlinear terms included in the filtering process greatly influence the performance of integration, especially in the case where the low quality INS is used in the integrated system.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126832932","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438036
Yin Bai, H. Zhuang
Traditional robot calibrations implement model-based and modeless methods. The calibration of position error in model-based method implements four steps: kinematic model definition of the robot, measurement process of the robot's positions, identification of the kinematic model of the robot and compensation of the position errors. This method is both time consuming and complicated because of the identification and compensation processes. Most traditional modeless methods are relatively simple and practical, but the calibration accuracy is relatively low and most of them are only suitable for the robots calibration in 2D domain and in relative small workspaces. This paper provides a novel modeless fuzzy interpolation method to improve the compensation accuracy for the robots calibration in 3D workspace. A comparison between the model-based and modeless fuzzy interpolation calibration method is made. The simulated results show that the modeless fuzzy interpolation calibration method is compatible with the model-based calibration method, and even outperforms a model-based counterpart in terms of accuracy and complexity in small workspaces.
{"title":"On the comparison of model-based and modeless robotic calibration based on the fuzzy interpolation technique","authors":"Yin Bai, H. Zhuang","doi":"10.1109/RAMECH.2004.1438036","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438036","url":null,"abstract":"Traditional robot calibrations implement model-based and modeless methods. The calibration of position error in model-based method implements four steps: kinematic model definition of the robot, measurement process of the robot's positions, identification of the kinematic model of the robot and compensation of the position errors. This method is both time consuming and complicated because of the identification and compensation processes. Most traditional modeless methods are relatively simple and practical, but the calibration accuracy is relatively low and most of them are only suitable for the robots calibration in 2D domain and in relative small workspaces. This paper provides a novel modeless fuzzy interpolation method to improve the compensation accuracy for the robots calibration in 3D workspace. A comparison between the model-based and modeless fuzzy interpolation calibration method is made. The simulated results show that the modeless fuzzy interpolation calibration method is compatible with the model-based calibration method, and even outperforms a model-based counterpart in terms of accuracy and complexity in small workspaces.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126768814","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1437988
A. Panga, B. Seth
In this paper we have presented a programmable hybrid mechanism (PHM) capable of producing various types of translatory profiles while carrying loads of up to 5 kilograms. The output is driven by a five bar mechanism, which, in turn, is driven by a servo input and a reference input. By choosing the correct trajectories of the servo input and the starting position, the torque sharing characteristics can be improved, such that the lowest rating servo motor will suffice. Thus providing flexibility at a reduced cost. Also the reference input which can be a constant speed motion can be derived from some other source, thus not needing a dedicated motor. Such a device can replace cams in applications where the functional relationship between the input and the output motions changes from time to time, such as packaging equipment and control of valve timings of IC engines. The PHM setup has been designed and fabricated. Simulation of the mechanism is carried out using ADAMS, to determine the size of servo motor. An approach to determine optimal control input to the mechanism for a given output profile is discussed. The experimental setup allows users to generate various cam profiles and study the deviations. Various profiles were generated within reasonable accuracy. A typical cam profile has been considered and optimization of control trajectory results in RMS torque reduction of 57%.
{"title":"Experimental study of hybrid cam mechanism","authors":"A. Panga, B. Seth","doi":"10.1109/RAMECH.2004.1437988","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1437988","url":null,"abstract":"In this paper we have presented a programmable hybrid mechanism (PHM) capable of producing various types of translatory profiles while carrying loads of up to 5 kilograms. The output is driven by a five bar mechanism, which, in turn, is driven by a servo input and a reference input. By choosing the correct trajectories of the servo input and the starting position, the torque sharing characteristics can be improved, such that the lowest rating servo motor will suffice. Thus providing flexibility at a reduced cost. Also the reference input which can be a constant speed motion can be derived from some other source, thus not needing a dedicated motor. Such a device can replace cams in applications where the functional relationship between the input and the output motions changes from time to time, such as packaging equipment and control of valve timings of IC engines. The PHM setup has been designed and fabricated. Simulation of the mechanism is carried out using ADAMS, to determine the size of servo motor. An approach to determine optimal control input to the mechanism for a given output profile is discussed. The experimental setup allows users to generate various cam profiles and study the deviations. Various profiles were generated within reasonable accuracy. A typical cam profile has been considered and optimization of control trajectory results in RMS torque reduction of 57%.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126526201","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438929
Abolfazl Jalilvand, S. Khanmohammadi
The branch and bound (BB) algorithm is one of the common used methods in solving the task scheduling problems in manufacturing systems. In this paper, we introduced a new method to apply the branch and bound algorithm with a reduced memory size. By this method the running time decreases considerably. The algorithm is applied to a combinational discrete job shop scheduling system, where a Petri net is used for modeling.
{"title":"Task scheduling in manufacturing systems based on an efficient branch and bound algorithm","authors":"Abolfazl Jalilvand, S. Khanmohammadi","doi":"10.1109/RAMECH.2004.1438929","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438929","url":null,"abstract":"The branch and bound (BB) algorithm is one of the common used methods in solving the task scheduling problems in manufacturing systems. In this paper, we introduced a new method to apply the branch and bound algorithm with a reduced memory size. By this method the running time decreases considerably. The algorithm is applied to a combinational discrete job shop scheduling system, where a Petri net is used for modeling.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"293 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124229844","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438029
Weiguo Lin, S. Jia, T. Abe, K. Takase
Localization is one of the most important fundament for mobile robot. A localization system with low cost, easy accomplishment, simplicity, effectiveness and robustness is the aim of researchers all the time. Here, we proposed a novel method for localization of mobile robot using ID tag and Web camera. In our method, the path map in an indoor environment is expressed with node tree, every node is represented with two landmarks: ID tag and card with the same colour. Pairs of two landmarks are affixed to ceiling of distinct locations, and the middle point of every pair of landmarks in a node indicates the absolute position or the node because of the unique ID of tag, the absolute position of mobile robot can be expressed with the absolute position of node and, position and orientation relative to this node. Localization is implemented with two steps: detecting ID tag in one node with RF communication and measuring position and orientation of mobile robot relative to this node with camera. In this paper, related works are summarized and the advantages of our method are introduced, the scheme of system is described in detail, a fast image processing algorithm for extracting landmarks from background and strategies for system robustness are discussed. Localization experiments show that with this method the errors or relative position and orientation are less than 2.5 cm and 2.5 degree. Navigation showed us that localization with ID tag and Web camera is feasible for navigation in indoor environment. At last, strategies for improving system are discussed.
{"title":"Localization of mobile robot based on ID tag and WEB camera","authors":"Weiguo Lin, S. Jia, T. Abe, K. Takase","doi":"10.1109/RAMECH.2004.1438029","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438029","url":null,"abstract":"Localization is one of the most important fundament for mobile robot. A localization system with low cost, easy accomplishment, simplicity, effectiveness and robustness is the aim of researchers all the time. Here, we proposed a novel method for localization of mobile robot using ID tag and Web camera. In our method, the path map in an indoor environment is expressed with node tree, every node is represented with two landmarks: ID tag and card with the same colour. Pairs of two landmarks are affixed to ceiling of distinct locations, and the middle point of every pair of landmarks in a node indicates the absolute position or the node because of the unique ID of tag, the absolute position of mobile robot can be expressed with the absolute position of node and, position and orientation relative to this node. Localization is implemented with two steps: detecting ID tag in one node with RF communication and measuring position and orientation of mobile robot relative to this node with camera. In this paper, related works are summarized and the advantages of our method are introduced, the scheme of system is described in detail, a fast image processing algorithm for extracting landmarks from background and strategies for system robustness are discussed. Localization experiments show that with this method the errors or relative position and orientation are less than 2.5 cm and 2.5 degree. Navigation showed us that localization with ID tag and Web camera is feasible for navigation in indoor environment. At last, strategies for improving system are discussed.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127876410","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438065
Probal Mitra, G. Niemeyer
Haptic simulations aim to provide users with realistic renditions of increasingly complex virtual environments. These may involve multiple users, multiple hands, and complex virtual tools. For example, in surgical training, simulators must recreate a tool in each hand of the user, interacting with each other as well as with the surrounding tissue. To further such developments, we introduce and demonstrate the concept of dynamic proxy objects. Proxies represent the physical master devices in the virtual world. Associating dynamics with these proxies allows greater control over the proxy motion and behavior, in particular in the context of collisions with fixed objects and between multiple proxies. We utilize first order velocity-based dynamics, so that the proxies remain massless. Geometric constraints are implemented in terms of velocity limits, as are dynamic interactions such as collisions. Complex tools, kinematic relationships, and even closed kinematic chains are incorporated, through Jacobian matrices. This approach is demonstrated in a simple experiment simulating interactions between two straight, slender virtual manipulators on a two-handed haptic console.
{"title":"Dynamic proxy objects in haptic simulations","authors":"Probal Mitra, G. Niemeyer","doi":"10.1109/RAMECH.2004.1438065","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438065","url":null,"abstract":"Haptic simulations aim to provide users with realistic renditions of increasingly complex virtual environments. These may involve multiple users, multiple hands, and complex virtual tools. For example, in surgical training, simulators must recreate a tool in each hand of the user, interacting with each other as well as with the surrounding tissue. To further such developments, we introduce and demonstrate the concept of dynamic proxy objects. Proxies represent the physical master devices in the virtual world. Associating dynamics with these proxies allows greater control over the proxy motion and behavior, in particular in the context of collisions with fixed objects and between multiple proxies. We utilize first order velocity-based dynamics, so that the proxies remain massless. Geometric constraints are implemented in terms of velocity limits, as are dynamic interactions such as collisions. Complex tools, kinematic relationships, and even closed kinematic chains are incorporated, through Jacobian matrices. This approach is demonstrated in a simple experiment simulating interactions between two straight, slender virtual manipulators on a two-handed haptic console.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127958936","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438041
Shawn Scharer, J. Baltes, J. Anderson
Accurate ego-motion estimation is a difficult problem that humans perform with relative ease. This paper describes two methods that are used in conjunction to estimate the ego motion of an intelligent autonomous vehicle from vision alone. First, a cross-correlation method is used to select a promising patch in the image. The optical flow information for this patch is used to determine linear and angular velocity of the intelligent autonomous vehicle. Lines in the image are then used to provide an estimate of the ego motion of the vehicle. The gradient of the line as well as the distance to the line allow the computation of current wheel velocities. Both methods have been implemented on real robots and have been tested in a treasure hunt competition. These methods greatly improved the exploration as well as accuracy of the generated maps of the environment.
{"title":"Practical ego-motion estimation for mobile robots","authors":"Shawn Scharer, J. Baltes, J. Anderson","doi":"10.1109/RAMECH.2004.1438041","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438041","url":null,"abstract":"Accurate ego-motion estimation is a difficult problem that humans perform with relative ease. This paper describes two methods that are used in conjunction to estimate the ego motion of an intelligent autonomous vehicle from vision alone. First, a cross-correlation method is used to select a promising patch in the image. The optical flow information for this patch is used to determine linear and angular velocity of the intelligent autonomous vehicle. Lines in the image are then used to provide an estimate of the ego motion of the vehicle. The gradient of the line as well as the distance to the line allow the computation of current wheel velocities. Both methods have been implemented on real robots and have been tested in a treasure hunt competition. These methods greatly improved the exploration as well as accuracy of the generated maps of the environment.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125951227","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438940
B. Yuksel, Changjiu Zhou, K. Leblebicioğlu
This paper aims to analyze the ground reaction force in terms of smooth transition and landing impact under the parametric change of frontal gait trajectory that is realized by inverted pendulum model and the parametric change in the proportional gain of PID feedback controller. Using a dynamic simulator, namely, SL simulator, the ground reaction force analysis is realized and the simulation results and comparison of them are presented.
{"title":"Ground reaction force analysis of biped locomotion","authors":"B. Yuksel, Changjiu Zhou, K. Leblebicioğlu","doi":"10.1109/RAMECH.2004.1438940","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438940","url":null,"abstract":"This paper aims to analyze the ground reaction force in terms of smooth transition and landing impact under the parametric change of frontal gait trajectory that is realized by inverted pendulum model and the parametric change in the proportional gain of PID feedback controller. Using a dynamic simulator, namely, SL simulator, the ground reaction force analysis is realized and the simulation results and comparison of them are presented.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128022713","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438052
M. Nagayoshi, S. Uchikado
We analyze the proposed correspondence methods in detail, and new interpretations of them are given so that new method is proposed based on this result. Here the epipole and the epipolar line play an important role. Then a method in general camera configuration is proposed. This method is easily constructed by using singular value decomposition and projective transformation. Furthermore it shows that this method is effective under the environment of a moving camera. Based on the new method proposed for the correspondence problem, we propose a method to detect moving objects by using a camera on a mobile robot.
{"title":"A study on detecting moving objects via projective transformation","authors":"M. Nagayoshi, S. Uchikado","doi":"10.1109/RAMECH.2004.1438052","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438052","url":null,"abstract":"We analyze the proposed correspondence methods in detail, and new interpretations of them are given so that new method is proposed based on this result. Here the epipole and the epipolar line play an important role. Then a method in general camera configuration is proposed. This method is easily constructed by using singular value decomposition and projective transformation. Furthermore it shows that this method is effective under the environment of a moving camera. Based on the new method proposed for the correspondence problem, we propose a method to detect moving objects by using a camera on a mobile robot.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125998303","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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