Pub Date : 2019-09-01DOI: 10.1109/ETFA.2019.8869359
Julen Balzategui, Luka Eciolaza, N. Arana-Arexolaleiba, Jon Altube, J. Aguerre, Iñaki Legarda-Ereño, A. Apraiz
Quality control of solar cells is a very important part of the production process. A little crack or joint failure can cause bad performance of the cell in the future, partly because the defective areas can be electrically disconnected from the active zones. Nowadays, one of the techniques to carry out this control is electroluminescence (EL), which allows obtaining high-resolution images of the cells where a visual and non-invasive inspection of defects can be done. This inspection is mostly performed by trained human operators. However, as the eyes become tired after a working day and the subjectivity of the operators, the accuracy with which the defect detection is done may be compromised. In order to solve this problem, a method to assist the operator in the inspection of polycrystalline silicon solar cells surface from EL images based on Convolutional Neural Networks is proposed. The method would classify the cells as defective and non-defective, and suggest those cells that are defective for re-inspection. Also, it would propose a segmentation map of the defects in the cell. To compensate for the lack of image samples in the dataset, each cell image is divided into regions by a sliding window. Then, each region is classified as defective or non-defective. And finally, all classifications related to the cell are resembled obtaining a segmented image of defective areas in the cell.
{"title":"Semi-automatic quality inspection of solar cell based on Convolutional Neural Networks","authors":"Julen Balzategui, Luka Eciolaza, N. Arana-Arexolaleiba, Jon Altube, J. Aguerre, Iñaki Legarda-Ereño, A. Apraiz","doi":"10.1109/ETFA.2019.8869359","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869359","url":null,"abstract":"Quality control of solar cells is a very important part of the production process. A little crack or joint failure can cause bad performance of the cell in the future, partly because the defective areas can be electrically disconnected from the active zones. Nowadays, one of the techniques to carry out this control is electroluminescence (EL), which allows obtaining high-resolution images of the cells where a visual and non-invasive inspection of defects can be done. This inspection is mostly performed by trained human operators. However, as the eyes become tired after a working day and the subjectivity of the operators, the accuracy with which the defect detection is done may be compromised. In order to solve this problem, a method to assist the operator in the inspection of polycrystalline silicon solar cells surface from EL images based on Convolutional Neural Networks is proposed. The method would classify the cells as defective and non-defective, and suggest those cells that are defective for re-inspection. Also, it would propose a segmentation map of the defects in the cell. To compensate for the lack of image samples in the dataset, each cell image is divided into regions by a sliding window. Then, each region is classified as defective or non-defective. And finally, all classifications related to the cell are resembled obtaining a segmented image of defective areas in the cell.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"24 1","pages":"529-535"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83289656","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869386
Caren Dripke, Yuesheng Sun, A. Verl
Until now, reconfigurable automation systems require a high engineering effort for the reconfiguration in order to begin production. Plug-and-play concepts are rare and usually only cover part of the disciplines involved in the mechatronic system. One of the challenges of reconfigurable systems considered in the research project DEVEKOS is the rearrangement of positioning axes into simple kinematic structures as it is required for the manufacturing process. In order to implement synchronous control of the multi-axes group, the calculation of the forward and inverse kinematics is necessary. This paper introduces a framework in which the kinematic description of the multi-axes group can be imported in a customized AutomationML-file. The framework then verifies the characteristics of the kinematics and considers common strategies for solving the inverse kinematics. The implementation presented recognizes four different types of basic kinematic structures and automatically calculates the inverse kinematic equations in those cases.
{"title":"Framework for the Closed-Form Calculation of Forward and Inverse Kinematics for Basic Kinematics in Reconfigurable Multi-Component Systems","authors":"Caren Dripke, Yuesheng Sun, A. Verl","doi":"10.1109/ETFA.2019.8869386","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869386","url":null,"abstract":"Until now, reconfigurable automation systems require a high engineering effort for the reconfiguration in order to begin production. Plug-and-play concepts are rare and usually only cover part of the disciplines involved in the mechatronic system. One of the challenges of reconfigurable systems considered in the research project DEVEKOS is the rearrangement of positioning axes into simple kinematic structures as it is required for the manufacturing process. In order to implement synchronous control of the multi-axes group, the calculation of the forward and inverse kinematics is necessary. This paper introduces a framework in which the kinematic description of the multi-axes group can be imported in a customized AutomationML-file. The framework then verifies the characteristics of the kinematics and considers common strategies for solving the inverse kinematics. The implementation presented recognizes four different types of basic kinematic structures and automatically calculates the inverse kinematic equations in those cases.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"25 1","pages":"687-694"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87970046","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869302
Daniel Rivas, L. Ribas-Xirgo
Transportation to solve intralogistics is becoming as complex as managing transportation in road logistics. Luckily, it takes place in structured environments where automation is easier. This work is about solving the task assignment problem for a group of automated guided vehicles (AGVs) serving the internal transport of a warehouse or factory. Instead of having a centralized task planner, we use an agent-based approach where agents represent all the stakeholders in the transport system. Namely, the clients are the transport orders and the taxis, the AGVs. We have modeled client and taxi behaviors by using extended finite-state stack machines (EFS2Ms) because they enable both modeling belief-desire-intention (BDI) agents and lower-level controllers. As a result, agent software is produced in a systematic way and, what is more, analyses of different working conditions can be done to fine-tune parameters of the models to achieve an efficient transportation. Results on one realistic study-case show that average service times can be shortened with respect to fixed planning and that this system can operate in legacy systems.
{"title":"Agent-based Model for Transport Order Assignment in AGV Systems","authors":"Daniel Rivas, L. Ribas-Xirgo","doi":"10.1109/ETFA.2019.8869302","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869302","url":null,"abstract":"Transportation to solve intralogistics is becoming as complex as managing transportation in road logistics. Luckily, it takes place in structured environments where automation is easier. This work is about solving the task assignment problem for a group of automated guided vehicles (AGVs) serving the internal transport of a warehouse or factory. Instead of having a centralized task planner, we use an agent-based approach where agents represent all the stakeholders in the transport system. Namely, the clients are the transport orders and the taxis, the AGVs. We have modeled client and taxi behaviors by using extended finite-state stack machines (EFS2Ms) because they enable both modeling belief-desire-intention (BDI) agents and lower-level controllers. As a result, agent software is produced in a systematic way and, what is more, analyses of different working conditions can be done to fine-tune parameters of the models to achieve an efficient transportation. Results on one realistic study-case show that average service times can be shortened with respect to fixed planning and that this system can operate in legacy systems.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"21 1","pages":"947-954"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88568584","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869108
K. Gibert, Conxi Pérez Andreu, Núria Castell
Gender gap in computer science related fields is one of the most critical among all technological areas. This paper describes the methodology used to create gender commissions and providing them of a territorial structure around informatics engineering and artificial intelligence, two close areas where the presence of women is critical both at professional level, as well as training level. Territorial structure provides an additional potential very useful for the impact of the activities of the commission. Here the creation of two gender structures in Catalonia is presented
{"title":"Deployment of territorial structures to reduce gender gap in technology and some real cases in Catalonia","authors":"K. Gibert, Conxi Pérez Andreu, Núria Castell","doi":"10.1109/ETFA.2019.8869108","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869108","url":null,"abstract":"Gender gap in computer science related fields is one of the most critical among all technological areas. This paper describes the methodology used to create gender commissions and providing them of a territorial structure around informatics engineering and artificial intelligence, two close areas where the presence of women is critical both at professional level, as well as training level. Territorial structure provides an additional potential very useful for the impact of the activities of the commission. Here the creation of two gender structures in Catalonia is presented","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"27 1","pages":"1823-1830"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83313157","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869301
Xie Zhen, Josh Chen Ye Seng, N. Somani
Many industry manufacturing processes require a lot of manpower to accomplish tasks manually, for example, manual polishing and masking. Industrial robot can be used to replace most of the tedious and repeated tasks. However, using robot program to generate the tool path for the manufacturing process might need programming skills and expertise. Besides, Computer Aided Design (CAD) files might not be available or accurate for the engineer to design the robot tool path. Hence, we propose an automatic way to generate the adaptive robot tool path for manufacturing process by using scan point cloud data of the target coupon. The core algorithm is based on point cloud projection on plane, tool path pattern design and reverse transform matrix to project the 2d tool path back to 3d point cloud. The algorithm is based on Point Cloud Library (PCL) and OpenCV libraries. After the toolpath is generated in the point cloud, Robot Operating System (ROS) is used to plan trajectory and check for collision. The automated tool path generation algorithm can be applied to multiple manufacturing process, such as masking, polishing and painting.
{"title":"Adaptive Automatic Robot Tool Path Generation Based on Point Cloud Projection Algorithm","authors":"Xie Zhen, Josh Chen Ye Seng, N. Somani","doi":"10.1109/ETFA.2019.8869301","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869301","url":null,"abstract":"Many industry manufacturing processes require a lot of manpower to accomplish tasks manually, for example, manual polishing and masking. Industrial robot can be used to replace most of the tedious and repeated tasks. However, using robot program to generate the tool path for the manufacturing process might need programming skills and expertise. Besides, Computer Aided Design (CAD) files might not be available or accurate for the engineer to design the robot tool path. Hence, we propose an automatic way to generate the adaptive robot tool path for manufacturing process by using scan point cloud data of the target coupon. The core algorithm is based on point cloud projection on plane, tool path pattern design and reverse transform matrix to project the 2d tool path back to 3d point cloud. The algorithm is based on Point Cloud Library (PCL) and OpenCV libraries. After the toolpath is generated in the point cloud, Robot Operating System (ROS) is used to plan trajectory and check for collision. The automated tool path generation algorithm can be applied to multiple manufacturing process, such as masking, polishing and painting.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"25 1","pages":"341-347"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80921944","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869451
Eneko Lerma, R. Costa-Castelló, R. Griñó, Carlos Sanchis
This document presents a project to develop freely redistributable materials to conduct educational lab projects with MATLAB, Simulink, Arduino and low-cost plants. This work materials introduce the fundamentals of Control Engineering through exercises and videos. Along with all this, the most important steps and issues appeared in the project are explained, so anyone interested on doing a project can have a starting point instead of starting a project from scratch, which most of times this results hard to implement.
{"title":"Duino-Based Learning (DBL) in Control Engineering Courses","authors":"Eneko Lerma, R. Costa-Castelló, R. Griñó, Carlos Sanchis","doi":"10.1109/ETFA.2019.8869451","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869451","url":null,"abstract":"This document presents a project to develop freely redistributable materials to conduct educational lab projects with MATLAB, Simulink, Arduino and low-cost plants. This work materials introduce the fundamentals of Control Engineering through exercises and videos. Along with all this, the most important steps and issues appeared in the project are explained, so anyone interested on doing a project can have a starting point instead of starting a project from scratch, which most of times this results hard to implement.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"89 1","pages":"798-803"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73553539","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869074
Frederick Prinz, Michael Schoeffler, A. Lechler, A. Verl
Future production systems are expected to support dynamic plug-and-produce scenarios across different component manufacturers. Therefore, the concept of I4.0 components was developed. An I4.0 component describes an asset with an asset administration shell providing a standardized representation of its capabilities. Real-time I4.0 components additionally demand for a deterministic communication with bounded low latency, where the network topology is typically defined by physical links and infrastructure. In order to avoid rewiring and to support dynamic plug-and-produce scenarios with real-time I4.0 components, we present so-called virtual topologies decoupled from the physical network infrastructure. Thereby, we extend the concept of real-time I4.0 components to configure the required behavior and introduce an additional submodel for the administration shell. Moreover, a central SDN controller is enhanced to automatically configure the virtual topologies during runtime. These topologies are based on the new real-time communication technology IEEE 802.1 Time-Sensitive Networking (TSN). Finally, we evaluate the latency of the prototypical implementation within real-time I4.0 components depending on the frame size and network bandwidth.
{"title":"Virtual Network Topologies for Real-time I4.0 Components based on Time-Sensitive Networking","authors":"Frederick Prinz, Michael Schoeffler, A. Lechler, A. Verl","doi":"10.1109/ETFA.2019.8869074","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869074","url":null,"abstract":"Future production systems are expected to support dynamic plug-and-produce scenarios across different component manufacturers. Therefore, the concept of I4.0 components was developed. An I4.0 component describes an asset with an asset administration shell providing a standardized representation of its capabilities. Real-time I4.0 components additionally demand for a deterministic communication with bounded low latency, where the network topology is typically defined by physical links and infrastructure. In order to avoid rewiring and to support dynamic plug-and-produce scenarios with real-time I4.0 components, we present so-called virtual topologies decoupled from the physical network infrastructure. Thereby, we extend the concept of real-time I4.0 components to configure the required behavior and introduce an additional submodel for the administration shell. Moreover, a central SDN controller is enhanced to automatically configure the virtual topologies during runtime. These topologies are based on the new real-time communication technology IEEE 802.1 Time-Sensitive Networking (TSN). Finally, we evaluate the latency of the prototypical implementation within real-time I4.0 components depending on the frame size and network bandwidth.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"10 1","pages":"1388-1391"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90770472","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8869024
Bjarne Johansson, B. Leander, Aida Čaušević, A. Papadopoulos, T. Nolte
In process automation installations, the I/O system connect the field devices to the process controller over a fieldbus, a reliable, real-time capable communication link with signal values cyclical being exchanged with a 10–100 millisecond rate. If a deviation from intended behaviour occurs, analyzing the potentially vast data recordings from the field can be a time consuming and cumbersome task for an engineer. For the engineer to be able to get a full understanding of the problem, knowledge of the used I/O configuration is required. In the problem report, the configuration description is sometimes missing. In such cases it is difficult to use the recorded data for analysis of the problem.In this paper we present our ongoing work towards using neural network models as assistance in the interpretation of an industrial fieldbus communication recording. To show the potential of such an approach we present an example using an industrial setup where fieldbus data is collected and classified. In this context we present an evaluation of the suitability of different neural net configurations and sizes for the problem at hand.
{"title":"Classification of PROFINET I/O Configurations utilizing Neural Networks","authors":"Bjarne Johansson, B. Leander, Aida Čaušević, A. Papadopoulos, T. Nolte","doi":"10.1109/ETFA.2019.8869024","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8869024","url":null,"abstract":"In process automation installations, the I/O system connect the field devices to the process controller over a fieldbus, a reliable, real-time capable communication link with signal values cyclical being exchanged with a 10–100 millisecond rate. If a deviation from intended behaviour occurs, analyzing the potentially vast data recordings from the field can be a time consuming and cumbersome task for an engineer. For the engineer to be able to get a full understanding of the problem, knowledge of the used I/O configuration is required. In the problem report, the configuration description is sometimes missing. In such cases it is difficult to use the recorded data for analysis of the problem.In this paper we present our ongoing work towards using neural network models as assistance in the interpretation of an industrial fieldbus communication recording. To show the potential of such an approach we present an example using an industrial setup where fieldbus data is collected and classified. In this context we present an evaluation of the suitability of different neural net configurations and sizes for the problem at hand.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"7 1","pages":"1321-1324"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78452908","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 : 2019-09-01DOI: 10.1109/etfa.2019.8869277
{"title":"Adaptive and Reconfigurable Cyber-Physical Systems [breaker page]","authors":"","doi":"10.1109/etfa.2019.8869277","DOIUrl":"https://doi.org/10.1109/etfa.2019.8869277","url":null,"abstract":"","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78821870","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 : 2019-09-01DOI: 10.1109/ETFA.2019.8868987
Rafael Herguedas, G. López-Nicolás, Rosario Aragues, C. Sagüés
Autonomous manipulation of deformable objects is a research topic of increasing interest due to the variety of current processes and applications that include this type of tasks. It is a complex problem that involves aspects such as modeling, control, perception, planning, grasping, estimation, etc. A single robot may be unable to perform the manipulation when the deformable object is too big, too heavy or difficult to grasp. Then, using multiple robots working together naturally arises as a solution to perform coordinately the manipulation task. In this paper, we contribute a survey of relevant state-of-the-art approaches concerning manipulation of deformable objects by multiple robots, which includes a specific classification with different criteria and a subsequent analysis of the leading methods, the main challenges and the future research directions.
{"title":"Survey on multi-robot manipulation of deformable objects","authors":"Rafael Herguedas, G. López-Nicolás, Rosario Aragues, C. Sagüés","doi":"10.1109/ETFA.2019.8868987","DOIUrl":"https://doi.org/10.1109/ETFA.2019.8868987","url":null,"abstract":"Autonomous manipulation of deformable objects is a research topic of increasing interest due to the variety of current processes and applications that include this type of tasks. It is a complex problem that involves aspects such as modeling, control, perception, planning, grasping, estimation, etc. A single robot may be unable to perform the manipulation when the deformable object is too big, too heavy or difficult to grasp. Then, using multiple robots working together naturally arises as a solution to perform coordinately the manipulation task. In this paper, we contribute a survey of relevant state-of-the-art approaches concerning manipulation of deformable objects by multiple robots, which includes a specific classification with different criteria and a subsequent analysis of the leading methods, the main challenges and the future research directions.","PeriodicalId":6682,"journal":{"name":"2019 24th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"49 1","pages":"977-984"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84720602","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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