Pub Date : 2010-06-24DOI: 10.1109/RAAD.2010.5524609
S. Herle, S. Man, G. Lazea, C. Marcu, P. Raica, R. Robotin
Myolectric control is nowadays the most used approach for electrically-powered upper limb prostheses. The myoelectric controllers use electromyographic (EMG) signals as inputs. These signals can be collected from the skin surface using surface EMG sensors, or intramuscular, using needle sensors. No matter which method is used, they have to be processed before being used as controller inputs. In this paper, we present an algorithm based on an autoregressive (AR) model representation and a neural network, for EMG signal classification. The results have shown that combining a low-order AR model with a feed-forward neural network, a rate of classification of 98% can be achieved, while keeping the computational cost low. We also present a hierarchical control architecture and the implementation of the high-level controller using Finite State Machine. The solution proposed is capable of controlling three joints (i.e. six movements) of the upper limb prosthesis. The inputs of the high-level controller are obtained from the classifier, while its outputs are applied as input signals for the low-level controller. The main advantage of the proposed strategy is the reduced effort required to the patient for controlling the prosthetic device, since he only has to initiate the movement that is finalized by the low-level part of the controller.
{"title":"Hierarchical myoelectric control of a human upper limb prosthesis","authors":"S. Herle, S. Man, G. Lazea, C. Marcu, P. Raica, R. Robotin","doi":"10.1109/RAAD.2010.5524609","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524609","url":null,"abstract":"Myolectric control is nowadays the most used approach for electrically-powered upper limb prostheses. The myoelectric controllers use electromyographic (EMG) signals as inputs. These signals can be collected from the skin surface using surface EMG sensors, or intramuscular, using needle sensors. No matter which method is used, they have to be processed before being used as controller inputs. In this paper, we present an algorithm based on an autoregressive (AR) model representation and a neural network, for EMG signal classification. The results have shown that combining a low-order AR model with a feed-forward neural network, a rate of classification of 98% can be achieved, while keeping the computational cost low. We also present a hierarchical control architecture and the implementation of the high-level controller using Finite State Machine. The solution proposed is capable of controlling three joints (i.e. six movements) of the upper limb prosthesis. The inputs of the high-level controller are obtained from the classifier, while its outputs are applied as input signals for the low-level controller. The main advantage of the proposed strategy is the reduced effort required to the patient for controlling the prosthetic device, since he only has to initiate the movement that is finalized by the low-level part of the controller.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129516944","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524606
E. Bauzano, V. Muñoz, I. García-Morales
This paper focuses on autonomous movements to aid the surgeon to perform certain tasks. Robotic assistants have solved the drawbacks of Minimally Invasive Surgery (MIS) and provide additional skills to the surgeons. However, some authors argue that these systems could lengthen the operating time. The solution is the automation of certain maneuvers that help the surgeon during a surgical maneuver. This work proposes control architecture for a surgical robot capable of performing autonomous movements. In this way, a trajectory planner based on a behavior concept computes the required velocity vector of the surgical instrument hold by the robot.
{"title":"A multi-behavior algorithm for auto-guided movements in surgeon assistance","authors":"E. Bauzano, V. Muñoz, I. García-Morales","doi":"10.1109/RAAD.2010.5524606","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524606","url":null,"abstract":"This paper focuses on autonomous movements to aid the surgeon to perform certain tasks. Robotic assistants have solved the drawbacks of Minimally Invasive Surgery (MIS) and provide additional skills to the surgeons. However, some authors argue that these systems could lengthen the operating time. The solution is the automation of certain maneuvers that help the surgeon during a surgical maneuver. This work proposes control architecture for a surgical robot capable of performing autonomous movements. In this way, a trajectory planner based on a behavior concept computes the required velocity vector of the surgical instrument hold by the robot.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126141367","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524593
C. Marcu, G. Lazea, S. Herle, R. Robotin, L. Tamás
This paper presents a portable 3D graphical simulator for a Fanuc M-6iB/2HS articulated robot. The mechanical structure is modeled using OpenGL functions implemented in Qt Framework. The robot motions are simulated based on the direct and inverse kinematics equations also presented in this paper. The simulator features include quick motion, step-by-step simulation, 3D scene control functions, objects selection functions and motion algorithms like joint interpolated motion and linear interpolated motion.
{"title":"3D graphical simulation of an articulated serial manipulator based on kinematic models","authors":"C. Marcu, G. Lazea, S. Herle, R. Robotin, L. Tamás","doi":"10.1109/RAAD.2010.5524593","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524593","url":null,"abstract":"This paper presents a portable 3D graphical simulator for a Fanuc M-6iB/2HS articulated robot. The mechanical structure is modeled using OpenGL functions implemented in Qt Framework. The robot motions are simulated based on the direct and inverse kinematics equations also presented in this paper. The simulator features include quick motion, step-by-step simulation, 3D scene control functions, objects selection functions and motion algorithms like joint interpolated motion and linear interpolated motion.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123040164","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524595
G. Skorc, R. Šafarič, A. Rojko
This paper describes an experimental approach to the positioning of a MEMS production system with a nano - scale resolution. Presented production system works on the basis of friction based piezo electric motors, which are being very hard for modeling. It is even being hard to describe this motors using classical mathematical functions, or to define them using other well known control procedures. Sophisticated control techniques are often required for successful positioning of such systems. In our work we present a simple control technique based on experimental results and polynomial equations. Presented polynomial control technique fulfils demands for positioning in sub-micrometer scale. Theory and practical results of proposed control technique are given within this paper.
{"title":"Polynomial control technique for adaptive positioning within sub-micrometer scale","authors":"G. Skorc, R. Šafarič, A. Rojko","doi":"10.1109/RAAD.2010.5524595","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524595","url":null,"abstract":"This paper describes an experimental approach to the positioning of a MEMS production system with a nano - scale resolution. Presented production system works on the basis of friction based piezo electric motors, which are being very hard for modeling. It is even being hard to describe this motors using classical mathematical functions, or to define them using other well known control procedures. Sophisticated control techniques are often required for successful positioning of such systems. In our work we present a simple control technique based on experimental results and polynomial equations. Presented polynomial control technique fulfils demands for positioning in sub-micrometer scale. Theory and practical results of proposed control technique are given within this paper.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128407565","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524573
Srecko Juric-Kavelj, I. Petrović
When tracking people or other moving objects with a mobile robot, detection is the first and most critical step. At first most researchers focused on the tracking algorithms, but recently AdaBoost (supervised machine learning technique) was used for people legs detection in 2D range data. The results are promising, but it is unclear if the obtained classifier could be used on the data from another sensor. As it would be a huge inconvenience having to train a classifier for every sensor (setup), we set out to find if, and when is a classifier trained on one sensor setup transferable to another sensor setup. We tested two sensors in five different setups. In total, we acquired 2455 range scans. Experiments showed that the classifier trained on noisier sensor data performed better at classification of data coming from other sensor setups. Classifiers trained on less noisy data were shown to be overconfident, and performed poorly on noisy data. Furthermore, experiments showed that classifiers learned on ten times smaller datasets performed as good as classifiers trained on larger datasets. Since AdaBoost is a supervised learning technique, obtaining same classifier efficiency with significantly smaller dataset means less hand labeling of the data for the same results.
{"title":"Experimental comparison of AdaBoost algorithms applied on leg detection with different range sensor setups","authors":"Srecko Juric-Kavelj, I. Petrović","doi":"10.1109/RAAD.2010.5524573","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524573","url":null,"abstract":"When tracking people or other moving objects with a mobile robot, detection is the first and most critical step. At first most researchers focused on the tracking algorithms, but recently AdaBoost (supervised machine learning technique) was used for people legs detection in 2D range data. The results are promising, but it is unclear if the obtained classifier could be used on the data from another sensor. As it would be a huge inconvenience having to train a classifier for every sensor (setup), we set out to find if, and when is a classifier trained on one sensor setup transferable to another sensor setup. We tested two sensors in five different setups. In total, we acquired 2455 range scans. Experiments showed that the classifier trained on noisier sensor data performed better at classification of data coming from other sensor setups. Classifiers trained on less noisy data were shown to be overconfident, and performed poorly on noisy data. Furthermore, experiments showed that classifiers learned on ten times smaller datasets performed as good as classifiers trained on larger datasets. Since AdaBoost is a supervised learning technique, obtaining same classifier efficiency with significantly smaller dataset means less hand labeling of the data for the same results.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117272588","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524562
K. Dobrovodský, P. Andris
A mechatronic vision system for the automatic acquisition and the monitoring of the static and the moving objects is proposed. The system recognizes the existence and the motion of relatively small objects from the background in order to report motion parameters while automatically tracking the selected object. The system consists of several relatively independent subsystems cooperating together with the aim to achieve the common goal to recognize objects of interest and to track their motion. The simultaneous tracking by the two cameras is used to measure the instant distance of the tracked object. The combination of an automatic recognition subsystem with an automatic object motion prediction and the dual camera orientation control facilitates the ability of the whole system to work autonomously in a real time. The system is designed in a modular way to enable simple adaptation to several static and mobile cameras mechanically oriented in space by the pan and tilt head. The open architecture of the system allows group management integration, day and night image processing, and various problem oriented geometric computation.
{"title":"Dual camera mechatronic tracking system","authors":"K. Dobrovodský, P. Andris","doi":"10.1109/RAAD.2010.5524562","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524562","url":null,"abstract":"A mechatronic vision system for the automatic acquisition and the monitoring of the static and the moving objects is proposed. The system recognizes the existence and the motion of relatively small objects from the background in order to report motion parameters while automatically tracking the selected object. The system consists of several relatively independent subsystems cooperating together with the aim to achieve the common goal to recognize objects of interest and to track their motion. The simultaneous tracking by the two cameras is used to measure the instant distance of the tracked object. The combination of an automatic recognition subsystem with an automatic object motion prediction and the dual camera orientation control facilitates the ability of the whole system to work autonomously in a real time. The system is designed in a modular way to enable simple adaptation to several static and mobile cameras mechanically oriented in space by the pan and tilt head. The open architecture of the system allows group management integration, day and night image processing, and various problem oriented geometric computation.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125431735","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524565
A. Byagowi, P. Kopacek
In this paper the method used to implement the natural human gait for a humanoid robot is presented. This work is part of the humanoid robot project called Archie. The project Archie started on 2004 in the Institute of Handling Robotics and Technology at Vienna University of Technology. The aim of this project is to build a robot that can imitate human's basic activities such as walking. In this work an image processing based technique has been used to extract the humans' walking trajectory, as a model for the robot. The same image processing method has been used to evaluate the robot's control system performance (traversed trajectory). Finally, the error obtained from the robot's test is shown and briefly discussed.
{"title":"Using Natural Human Gait for a humanoid robot","authors":"A. Byagowi, P. Kopacek","doi":"10.1109/RAAD.2010.5524565","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524565","url":null,"abstract":"In this paper the method used to implement the natural human gait for a humanoid robot is presented. This work is part of the humanoid robot project called Archie. The project Archie started on 2004 in the Institute of Handling Robotics and Technology at Vienna University of Technology. The aim of this project is to build a robot that can imitate human's basic activities such as walking. In this work an image processing based technique has been used to extract the humans' walking trajectory, as a model for the robot. The same image processing method has been used to evaluate the robot's control system performance (traversed trajectory). Finally, the error obtained from the robot's test is shown and briefly discussed.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127186605","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524590
M. Balucani, N. Belfiore, R. Crescenzi, M. Verotti
Microrobots are used nowadays in several fields of application, specially in mini invasive surgery. However, they are rather difficult to be constructed, and the traditional micro machining tools are not adequate yet to built the smaller parts. The construction of the microrobots is even harder if more than one D.O.F. are required for the mechanism, because these systems are more complicated. This paper deals with the development of a 3 D.O.F. planar micro platform with remote system of actuation. The new approach of design and manufacturing is based on two innovative solutions: a) the adoption of the technologies used to built MEMS, Micro Electro Mechanical Systems; b) the introduction of new flexural hinge to develop compliant micro mechanisms. The new concept of flexural hinge is described in the paper, also from a theoretical point of view. Several example of possible structures are proposed and analyzed, together with their remote wire actuation systems. Finite Element Analysis (FEA) has been also adopted to analyze the system performance under small deformations. The principle of fabrication is, then, described. The process consists of a sequence of single steps which have allowed to achieved an overall maximum size down to 3–4 mm and the minimum thickness of the smaller components down to 50µm.
{"title":"The development of a MEMS/NEMS-based 3 D.O.F. compliant micro robot","authors":"M. Balucani, N. Belfiore, R. Crescenzi, M. Verotti","doi":"10.1109/RAAD.2010.5524590","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524590","url":null,"abstract":"Microrobots are used nowadays in several fields of application, specially in mini invasive surgery. However, they are rather difficult to be constructed, and the traditional micro machining tools are not adequate yet to built the smaller parts. The construction of the microrobots is even harder if more than one D.O.F. are required for the mechanism, because these systems are more complicated. This paper deals with the development of a 3 D.O.F. planar micro platform with remote system of actuation. The new approach of design and manufacturing is based on two innovative solutions: a) the adoption of the technologies used to built MEMS, Micro Electro Mechanical Systems; b) the introduction of new flexural hinge to develop compliant micro mechanisms. The new concept of flexural hinge is described in the paper, also from a theoretical point of view. Several example of possible structures are proposed and analyzed, together with their remote wire actuation systems. Finite Element Analysis (FEA) has been also adopted to analyze the system performance under small deformations. The principle of fabrication is, then, described. The process consists of a sequence of single steps which have allowed to achieved an overall maximum size down to 3–4 mm and the minimum thickness of the smaller components down to 50µm.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123577100","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524604
A. M. Bertetto, C. Falchi, R. Pinna, R. Ricciu
This work is concerned with a mechanical system designed to harvest Crocus Sativus (saffron) flowers. The system is conceived as a shoulder portable device with two main parts: the first one is specifically designed to detach the flower containing three stigmas, which are the costly final product; the second one is aimed to collect the detached flower through a vacuum collector. The system is carried by the human operator on his back. This paper describes the operating principle of the detaching and of the harvesting devices. The former device imitates one of the procedures followed by the pickers but with the peculiarity that allows to harvest the flower without separating it from its leaves, which is a significant advantage since it simplifies the mechanical detachment of the flower. The paper also deals with some experimental tests in the laboratory carried out in order to highlight the dynamic behaviour of the detaching and of the harvesting devices.
{"title":"An integrated device for saffron flowers detaching and harvesting","authors":"A. M. Bertetto, C. Falchi, R. Pinna, R. Ricciu","doi":"10.1109/RAAD.2010.5524604","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524604","url":null,"abstract":"This work is concerned with a mechanical system designed to harvest Crocus Sativus (saffron) flowers. The system is conceived as a shoulder portable device with two main parts: the first one is specifically designed to detach the flower containing three stigmas, which are the costly final product; the second one is aimed to collect the detached flower through a vacuum collector. The system is carried by the human operator on his back. This paper describes the operating principle of the detaching and of the harvesting devices. The former device imitates one of the procedures followed by the pickers but with the peculiarity that allows to harvest the flower without separating it from its leaves, which is a significant advantage since it simplifies the mechanical detachment of the flower. The paper also deals with some experimental tests in the laboratory carried out in order to highlight the dynamic behaviour of the detaching and of the harvesting devices.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126279147","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 : 2010-06-24DOI: 10.1109/RAAD.2010.5524597
L. Vokorokos, N. Ádám, B. Madoš
The architecture described in this article belongs to a class of dynamic data flow architectures, in which the operand process control significantly affects the performance parameters as well as the system characteristics of the given architecture. The main component of the presented architecture is the multifunctional pipeline unit, which handles processing of data tokens representing the instructions of the program. This article describes the pipelined single operand data flow operators process control.
{"title":"The process control for P-single operators","authors":"L. Vokorokos, N. Ádám, B. Madoš","doi":"10.1109/RAAD.2010.5524597","DOIUrl":"https://doi.org/10.1109/RAAD.2010.5524597","url":null,"abstract":"The architecture described in this article belongs to a class of dynamic data flow architectures, in which the operand process control significantly affects the performance parameters as well as the system characteristics of the given architecture. The main component of the presented architecture is the multifunctional pipeline unit, which handles processing of data tokens representing the instructions of the program. This article describes the pipelined single operand data flow operators process control.","PeriodicalId":104308,"journal":{"name":"19th International Workshop on Robotics in Alpe-Adria-Danube Region (RAAD 2010)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130521317","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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