Pub Date : 2018-11-01DOI: 10.1109/M2VIP.2018.8600819
Keyur D. Joshi, B. Surgenor
A Flexible Machine Vision (FMV) Inspection System has been developed that requires minimal retuning in hardware and software as applications are changed up. The flexibility of the system was evaluated by applying it to an inspection problem with three different types of small parts: plastic gears, plastic connectors and metallic coins, with minimal retuning when moving from one application to the others. The system was required to differentiate between 4 different known styles of each part plus one unknown style, for a total of 5 classes. In previous work, a hybrid Support Vector Machine (SVM) classifier was developed for the connector application. When applied to the coin application, the hybrid SVM could not achieve the target performance of 95% accuracy. A new hybrid that method that combines SVM and an Artificial Neural Network (ANN) or ANN-SVM classifier was subsequently developed to overcome this problem and the results are presented in this paper. The image library used in this study is available at http://my.me.queensu.ca/People/Surgenor/Laboratory/Database.html
{"title":"Small Parts Classification with Flexible Machine Vision and a Hybrid Classifier","authors":"Keyur D. Joshi, B. Surgenor","doi":"10.1109/M2VIP.2018.8600819","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600819","url":null,"abstract":"A Flexible Machine Vision (FMV) Inspection System has been developed that requires minimal retuning in hardware and software as applications are changed up. The flexibility of the system was evaluated by applying it to an inspection problem with three different types of small parts: plastic gears, plastic connectors and metallic coins, with minimal retuning when moving from one application to the others. The system was required to differentiate between 4 different known styles of each part plus one unknown style, for a total of 5 classes. In previous work, a hybrid Support Vector Machine (SVM) classifier was developed for the connector application. When applied to the coin application, the hybrid SVM could not achieve the target performance of 95% accuracy. A new hybrid that method that combines SVM and an Artificial Neural Network (ANN) or ANN-SVM classifier was subsequently developed to overcome this problem and the results are presented in this paper. The image library used in this study is available at http://my.me.queensu.ca/People/Surgenor/Laboratory/Database.html","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117061036","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600874
Lei Tang, Limin Zhu, Xiangyang Zhu, Guoying Gu
Cable-driven snake robots have the ability to slither around narrow space owing to slender structure and high degrees of freedom (DOFs). Due to the high DOFs, the inverse kinematics of the snake robot is nonlinear and has no unique solution, which makes the motion planning quite difficult. In this paper, a serpentine curve based method is presented to simplify the motion planning process. Firstly, the configuration of the cable-driven snake robots is represented by a serpentine curve. Secondly, the serpentine curve is determined to satisfy the obstacle constraints. Finally, the robot moves along the planned curves. The serpentine curve has much less parameters than the DOFs of the robot. Letting the robot slither along the planned curves, the dimensions of motion planning can be reduced significantly. Simulations and experiments on a 25 DOFs cable-driven snake robots prototype demonstrate the effectiveness of the presented method.
{"title":"A Serpentine Curve Based Motion Planning Method for Cable-Driven Snake Robots","authors":"Lei Tang, Limin Zhu, Xiangyang Zhu, Guoying Gu","doi":"10.1109/M2VIP.2018.8600874","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600874","url":null,"abstract":"Cable-driven snake robots have the ability to slither around narrow space owing to slender structure and high degrees of freedom (DOFs). Due to the high DOFs, the inverse kinematics of the snake robot is nonlinear and has no unique solution, which makes the motion planning quite difficult. In this paper, a serpentine curve based method is presented to simplify the motion planning process. Firstly, the configuration of the cable-driven snake robots is represented by a serpentine curve. Secondly, the serpentine curve is determined to satisfy the obstacle constraints. Finally, the robot moves along the planned curves. The serpentine curve has much less parameters than the DOFs of the robot. Letting the robot slither along the planned curves, the dimensions of motion planning can be reduced significantly. Simulations and experiments on a 25 DOFs cable-driven snake robots prototype demonstrate the effectiveness of the presented method.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127270725","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600913
Simon Wolfen, Johannes R. Walter, M. Günther, D. Haeufle, S. Schmitt
Pneumatic actuators have become an applicable solution for robotic movement generation in the last decades. Among them, pneumatic actuated muscles (PAMs) which are known as McKibben muscles. They clone the biological operating principle which means, that they can only contract and create tensile force. Mounted in a bioinspired agonistic-antagonistic setup (AAS) of a robotic joint, their benefits lay especially in the adjustable joint torque and stiffness. However, when mounted in an AAS, the PAMs divulge their weakness: The limited passive abilities of the PAMs enforce the AAS to be preloaded. Inspired by nature, Klute investigated a PAM with a serial elastic element and a damper to mimic the muscle tendon unit of the biological system. Based on this approach, we offer calculable AAS models and show design possibilities in this contribution.
{"title":"Bioinspired pneumatic muscle spring units mimicking the human motion apparatus: benefits for passive motion range and joint stiffness variation in antagonistic setups","authors":"Simon Wolfen, Johannes R. Walter, M. Günther, D. Haeufle, S. Schmitt","doi":"10.1109/M2VIP.2018.8600913","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600913","url":null,"abstract":"Pneumatic actuators have become an applicable solution for robotic movement generation in the last decades. Among them, pneumatic actuated muscles (PAMs) which are known as McKibben muscles. They clone the biological operating principle which means, that they can only contract and create tensile force. Mounted in a bioinspired agonistic-antagonistic setup (AAS) of a robotic joint, their benefits lay especially in the adjustable joint torque and stiffness. However, when mounted in an AAS, the PAMs divulge their weakness: The limited passive abilities of the PAMs enforce the AAS to be preloaded. Inspired by nature, Klute investigated a PAM with a serial elastic element and a damper to mimic the muscle tendon unit of the biological system. Based on this approach, we offer calculable AAS models and show design possibilities in this contribution.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129339767","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600908
Joao Lopes, José Puche Planells, A. Verl
Nowadays, with the increasing influence of Information Technologies in the Automation, new solutions for old problems are available. One example is the Power Line communication: using recent telecommunication techniques, it is possible to communicate at the field level with Industrial Real-Time Ethernet using Power Line, saving costs and time.
{"title":"Real-Time Ethernet over Power Line","authors":"Joao Lopes, José Puche Planells, A. Verl","doi":"10.1109/M2VIP.2018.8600908","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600908","url":null,"abstract":"Nowadays, with the increasing influence of Information Technologies in the Automation, new solutions for old problems are available. One example is the Power Line communication: using recent telecommunication techniques, it is possible to communicate at the field level with Industrial Real-Time Ethernet using Power Line, saving costs and time.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115875271","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600910
F. Eger, C. Reiff, M. Colledani, A. Verl
The increasing complexity of parts and the growing quality requirements pose new challenges for today’s manufacturing industry. Multi-Stage Production Systems, which are known for complex links and sequences of many different process steps, must be adapted to these requirements. This means, being cost-effective and flexible while still meeting high quality standards. The idea of Zero-Defect Manufacturing aims to reduce scrap, rework and special operations by analyzing and optimizing multi-stage production systems through data-driven and learning-based approaches. A Knowledge Capturing Platform concept is introduced to extract a deeper understanding from collected data with inter-stage correlation methods, part variation approaches along the line and intelligent monitoring systems.
{"title":"Knowledge Capturing Platform in Multi-Stage Production Systems for Zero-Defect Manufacturing","authors":"F. Eger, C. Reiff, M. Colledani, A. Verl","doi":"10.1109/M2VIP.2018.8600910","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600910","url":null,"abstract":"The increasing complexity of parts and the growing quality requirements pose new challenges for today’s manufacturing industry. Multi-Stage Production Systems, which are known for complex links and sequences of many different process steps, must be adapted to these requirements. This means, being cost-effective and flexible while still meeting high quality standards. The idea of Zero-Defect Manufacturing aims to reduce scrap, rework and special operations by analyzing and optimizing multi-stage production systems through data-driven and learning-based approaches. A Knowledge Capturing Platform concept is introduced to extract a deeper understanding from collected data with inter-stage correlation methods, part variation approaches along the line and intelligent monitoring systems.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132240366","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600872
Zezhou Li, H. Lau, Xiaoyu Chen, Jiao Wang, Shen Shen, P. Sun
The dielectric constant of dielectric elastomer(DE) is an important physical parameter that affects the performance of DE actuator. A number of factors may cause an effect on the value of the dielectric constant. In this paper, an extensive experimental study has been conducted to investigate the relation between dielectric constant and two factors, electrical frequency and biaxial prestretch ratio quantitatively. The experimental results show that the dielectric constant varies with the variation of the frequency of the sensing signal and prestretch ratio. The analyses and the recorded results provide a reference to researchers about the quantitative control of dielectric elastomer actuator relating to the two key parameters. An experimental platform has been developed for actuating and sensing of a prototype dielectric elastomer actuator that demonstrates the design for actuating and self-sensing control under varying dielectric constant. An area stretch ratio of more than 220% is obtained through the proposed design.
{"title":"Experimental Study on the Variation of Dielectric Constant of Dielectric Elastomer Actuator","authors":"Zezhou Li, H. Lau, Xiaoyu Chen, Jiao Wang, Shen Shen, P. Sun","doi":"10.1109/M2VIP.2018.8600872","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600872","url":null,"abstract":"The dielectric constant of dielectric elastomer(DE) is an important physical parameter that affects the performance of DE actuator. A number of factors may cause an effect on the value of the dielectric constant. In this paper, an extensive experimental study has been conducted to investigate the relation between dielectric constant and two factors, electrical frequency and biaxial prestretch ratio quantitatively. The experimental results show that the dielectric constant varies with the variation of the frequency of the sensing signal and prestretch ratio. The analyses and the recorded results provide a reference to researchers about the quantitative control of dielectric elastomer actuator relating to the two key parameters. An experimental platform has been developed for actuating and sensing of a prototype dielectric elastomer actuator that demonstrates the design for actuating and self-sensing control under varying dielectric constant. An area stretch ratio of more than 220% is obtained through the proposed design.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132421862","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600916
Zixiao Chen, Zhicong Deng, J. Dhupia, M. Stommel, Weiliang Xu
In this paper, the deformation details of a soft actuator of a soft surface manipulator was investigated. The relation between the pressure of the inflation and the object displacement was established. Finite Element Analysis was used to investigate the working principle of single soft actuator. The simulation results show how the soft actuators effect the movement of the object on the surface. The relation between inflation pressure and object displacement was established by applying different pressure to the Finite Element model. The soft surface manipulator was considered as a servo mechanism acting on the object. The kinematic model of the object was established to facilitate the development of trajectory tracking algorithm in the future work.
{"title":"Modelling of a Soft Actuator for a Planar Manipulator Table","authors":"Zixiao Chen, Zhicong Deng, J. Dhupia, M. Stommel, Weiliang Xu","doi":"10.1109/M2VIP.2018.8600916","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600916","url":null,"abstract":"In this paper, the deformation details of a soft actuator of a soft surface manipulator was investigated. The relation between the pressure of the inflation and the object displacement was established. Finite Element Analysis was used to investigate the working principle of single soft actuator. The simulation results show how the soft actuators effect the movement of the object on the surface. The relation between inflation pressure and object displacement was established by applying different pressure to the Finite Element model. The soft surface manipulator was considered as a servo mechanism acting on the object. The kinematic model of the object was established to facilitate the development of trajectory tracking algorithm in the future work.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115375886","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 : 2018-11-01DOI: 10.1007/978-981-13-7983-3_7
Zhiyong Wang, Jingjing Liu, Honghai Liu
{"title":"A preliminary visual system for assistant diagnosis of ASD","authors":"Zhiyong Wang, Jingjing Liu, Honghai Liu","doi":"10.1007/978-981-13-7983-3_7","DOIUrl":"https://doi.org/10.1007/978-981-13-7983-3_7","url":null,"abstract":"","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"48 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132871457","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 : 2018-11-01DOI: 10.1109/M2VIP.2018.8600899
Kaiwei Ma, Xingsong Wang, Donghua Shen
Aiming at the problems of the lack of engineering practice in robotic grinding, a robotic belt grinding automation production system for complex surface workpiece is designed and built, which is based on the application of hand-grinding production line and industrial robot. In order to design the belt grinder, some key parameters such as driving wheel diameter, belt tension and tension cylinder bore are calculated. On this basis, the construction of the belt grinder is completed. Meanwhile, a robotic belt grinding control system is set up by using fieldbus and serial port. The system has constant grinding force control module. In the module, it uses the motor current and the adjustment distance of the robot to achieve the constant control of grinding force. The simulation environment of the system is established by using the software Robot Studio. It can realize off-line programming and online simulation of the machining path. Taking a faucet as a test, its results show that the surface roughnesses of fine grinding are below 0.9 microns. The results fully meet the requirements of parts surface grinding. It provides a theoretical basis and experimental reference for the development of industrial robotic belt grinding system.
{"title":"Design and Experiment of Robotic Belt Grinding System with Constant Grinding Force","authors":"Kaiwei Ma, Xingsong Wang, Donghua Shen","doi":"10.1109/M2VIP.2018.8600899","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600899","url":null,"abstract":"Aiming at the problems of the lack of engineering practice in robotic grinding, a robotic belt grinding automation production system for complex surface workpiece is designed and built, which is based on the application of hand-grinding production line and industrial robot. In order to design the belt grinder, some key parameters such as driving wheel diameter, belt tension and tension cylinder bore are calculated. On this basis, the construction of the belt grinder is completed. Meanwhile, a robotic belt grinding control system is set up by using fieldbus and serial port. The system has constant grinding force control module. In the module, it uses the motor current and the adjustment distance of the robot to achieve the constant control of grinding force. The simulation environment of the system is established by using the software Robot Studio. It can realize off-line programming and online simulation of the machining path. Taking a faucet as a test, its results show that the surface roughnesses of fine grinding are below 0.9 microns. The results fully meet the requirements of parts surface grinding. It provides a theoretical basis and experimental reference for the development of industrial robotic belt grinding system.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"1162 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114161941","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}
In recent years, surface electromyography (sEMG) is widely used in human-computer interface (HCI). For example, it is used for prosthetic manipulation to improve the quality of amputees’ life. However, sEMG approaches has some drawbacks such as poor robustness of the electrode-skin interface. Near-infrared spectroscopy (NIRS) and mechanomyography (MMG) can also monitor muscle motion. Comparing with approaches that only use sEMG signal, hybrid sEMG, NIRS and MMG sensor system will have better system performance. Investigations about the fusion of sEMG, NIRS and MMG are scant. This paper presents a hybrid sEMG, NIRS and MMG sensor system and puts it into practice. Fuse surface electromyography, near-infrared spectroscopy and mechanomyography acquisition circuits into a compact sensor, which can measure the muscle motion from the modalities of electrophysiology, optics and acoustics. Using the hybrid sensor system, incremental grip force experiment is carried out to explore the relationship between the three signals, blood oxygen metabolism and grip force. And muscle fatigue is carried out in order to explain the phenomenon of muscle fatigue from the perspective of electrophysiology, blood oxygen metabolism and mechanomyography.
{"title":"Hybrid sEMG, NIRS and MMG Sensor System","authors":"Xuecong Ding, Mian Wang, Weichao Guo, X. Sheng, Xiangyang Zhu","doi":"10.1109/M2VIP.2018.8600866","DOIUrl":"https://doi.org/10.1109/M2VIP.2018.8600866","url":null,"abstract":"In recent years, surface electromyography (sEMG) is widely used in human-computer interface (HCI). For example, it is used for prosthetic manipulation to improve the quality of amputees’ life. However, sEMG approaches has some drawbacks such as poor robustness of the electrode-skin interface. Near-infrared spectroscopy (NIRS) and mechanomyography (MMG) can also monitor muscle motion. Comparing with approaches that only use sEMG signal, hybrid sEMG, NIRS and MMG sensor system will have better system performance. Investigations about the fusion of sEMG, NIRS and MMG are scant. This paper presents a hybrid sEMG, NIRS and MMG sensor system and puts it into practice. Fuse surface electromyography, near-infrared spectroscopy and mechanomyography acquisition circuits into a compact sensor, which can measure the muscle motion from the modalities of electrophysiology, optics and acoustics. Using the hybrid sensor system, incremental grip force experiment is carried out to explore the relationship between the three signals, blood oxygen metabolism and grip force. And muscle fatigue is carried out in order to explain the phenomenon of muscle fatigue from the perspective of electrophysiology, blood oxygen metabolism and mechanomyography.","PeriodicalId":365579,"journal":{"name":"2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP)","volume":"440 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123863682","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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