Pub Date : 2019-10-01DOI: 10.1109/ICMECT.2019.8932141
R. Moeini, P. Weston, P. Tricoli, T. Dinh, A. McGordon, D. Hughes
The majority of electrical failures in wind turbines occur in the semiconductor components (IGBTs) of converters. To increase reliability and decrease the maintenance costs associated with this component, several health-monitoring methods have been proposed in the literature. Many laboratory-based tests have been conducted to detect the failure mechanisms of the IGBT in their early stages through monitoring the variations of thermo-sensitive electrical parameters. The methods are generally proposed and validated with a single-phase converter with an air-cored inductive or resistive load. However, limited work has been carried out considering limitations associated with measurement and processing of these parameters in a three-phase converter. Furthermore, looking at just variations of the module junction temperature will most likely lead to unreliable health monitoring as different failure mechanisms have their own individual effects on temperature variations of some, or all, of the electrical parameters. A reliable health monitoring system is necessary to determine whether the temperature variations are due to the presence of a premature failure or from normal converter operation. To address this issue, a temperature measurement approach should be independent from the failure mechanisms. In this paper, temperature is estimated by monitoring an electrical parameter particularly affected by different failure types. Early bond wire lift-off is detected by another electrical parameter that is sensitive to the progress of the failure. Considering two separate electrical parameters, one for estimation of temperature (switching off time) and another to detect the premature bond wire lift-off (collector emitter on-state voltage) enhance the reliability of an IGBT could increase the accuracy of the temperature estimation as well as premature failure detection.
{"title":"Enhancement of Reliability in Condition Monitoring Techniques in Wind Turbines","authors":"R. Moeini, P. Weston, P. Tricoli, T. Dinh, A. McGordon, D. Hughes","doi":"10.1109/ICMECT.2019.8932141","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932141","url":null,"abstract":"The majority of electrical failures in wind turbines occur in the semiconductor components (IGBTs) of converters. To increase reliability and decrease the maintenance costs associated with this component, several health-monitoring methods have been proposed in the literature. Many laboratory-based tests have been conducted to detect the failure mechanisms of the IGBT in their early stages through monitoring the variations of thermo-sensitive electrical parameters. The methods are generally proposed and validated with a single-phase converter with an air-cored inductive or resistive load. However, limited work has been carried out considering limitations associated with measurement and processing of these parameters in a three-phase converter. Furthermore, looking at just variations of the module junction temperature will most likely lead to unreliable health monitoring as different failure mechanisms have their own individual effects on temperature variations of some, or all, of the electrical parameters. A reliable health monitoring system is necessary to determine whether the temperature variations are due to the presence of a premature failure or from normal converter operation. To address this issue, a temperature measurement approach should be independent from the failure mechanisms. In this paper, temperature is estimated by monitoring an electrical parameter particularly affected by different failure types. Early bond wire lift-off is detected by another electrical parameter that is sensitive to the progress of the failure. Considering two separate electrical parameters, one for estimation of temperature (switching off time) and another to detect the premature bond wire lift-off (collector emitter on-state voltage) enhance the reliability of an IGBT could increase the accuracy of the temperature estimation as well as premature failure detection.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124955542","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932135
Yung-Tien Liu, Wei-Hsuan Su
In this study, a position acquisition device (PAD) was developed for efficiently examining the motion characteristics of a machine tool. The PAD was based upon employing high-precision guideways that is with a similar configuration as the on-machine measurement. The PAD was implemented by a real-time (RT) controller with reconfigurable input/output modules. Through experimental examinations for linear, rotational, and multi-axis synchronous motions, the developed PAD that could real-time evaluate the motion characteristics of a machine tool was demonstrated. This can be applied to smart manufacturing for monitoring machining performance. Future works are to improve memory capacity for position information storage and to configure an easy setup of a portable device.
{"title":"Development of a Position Acquisition Device for Examining Motion Behaviors of a Machine Tool","authors":"Yung-Tien Liu, Wei-Hsuan Su","doi":"10.1109/ICMECT.2019.8932135","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932135","url":null,"abstract":"In this study, a position acquisition device (PAD) was developed for efficiently examining the motion characteristics of a machine tool. The PAD was based upon employing high-precision guideways that is with a similar configuration as the on-machine measurement. The PAD was implemented by a real-time (RT) controller with reconfigurable input/output modules. Through experimental examinations for linear, rotational, and multi-axis synchronous motions, the developed PAD that could real-time evaluate the motion characteristics of a machine tool was demonstrated. This can be applied to smart manufacturing for monitoring machining performance. Future works are to improve memory capacity for position information storage and to configure an easy setup of a portable device.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128980492","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932108
Chao Deng
This paper proposes a distributed resilient control method for the consensus problem of cyber-physical systems under denial-of-service attacks. Compared with the existing denial-of-service attacks results on multi-agent systems, network communication delays among agents are considered in this paper. To avoid the asynchronous phenomenon caused by communication delays, a distributed resilient controller is designed by introducing a switching mechanism in the controller. A sufficient condition based on duration and frequency of denial-of-service attacks is derived by using the dwell time analysis method. Besides, it can be shown that the developed resilient control method can guarantee the exponentially convergent of the consensus errors. Finally, a simulation example is given to show the validity of the developed approach.
{"title":"Distributed Resilient Control for Cyber-Physical Systems under Denial-of-Service Attacks","authors":"Chao Deng","doi":"10.1109/ICMECT.2019.8932108","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932108","url":null,"abstract":"This paper proposes a distributed resilient control method for the consensus problem of cyber-physical systems under denial-of-service attacks. Compared with the existing denial-of-service attacks results on multi-agent systems, network communication delays among agents are considered in this paper. To avoid the asynchronous phenomenon caused by communication delays, a distributed resilient controller is designed by introducing a switching mechanism in the controller. A sufficient condition based on duration and frequency of denial-of-service attacks is derived by using the dwell time analysis method. Besides, it can be shown that the developed resilient control method can guarantee the exponentially convergent of the consensus errors. Finally, a simulation example is given to show the validity of the developed approach.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115850807","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 : 2019-10-01DOI: 10.1109/icmect.2019.8932125
Aswec, Mingyu Guo, Mojtaba Shahin, P. Kannan
s 9th Singular Days University of Kassel, September 17 – 20, 2019
{"title":"Local Organizing Committee","authors":"Aswec, Mingyu Guo, Mojtaba Shahin, P. Kannan","doi":"10.1109/icmect.2019.8932125","DOIUrl":"https://doi.org/10.1109/icmect.2019.8932125","url":null,"abstract":"s 9th Singular Days University of Kassel, September 17 – 20, 2019","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130951416","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932100
Ryota Kito, Keigo Takasugi, N. Asakawa, Takahiko Mizutani
In recent years, product shapes have become complicated, and a cutting simulator that can confirm the shape before actual machining is strongly required. In most cases, simulators are developed using a concept called a “voxel.” Voxel representation shapes 3D models, including tools and workpieces, with a set of minute cubes. However, voxel representation has a disadvantage in that it is difficult to accelerate the simulation. Therefore, this study used polygon representation instead of voxel representation. A cutting simulator was developed using the Vatti clipping algorithm from the computer graphics field.
{"title":"Development of 3D Cutting Simulator using Vatti Clipping","authors":"Ryota Kito, Keigo Takasugi, N. Asakawa, Takahiko Mizutani","doi":"10.1109/ICMECT.2019.8932100","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932100","url":null,"abstract":"In recent years, product shapes have become complicated, and a cutting simulator that can confirm the shape before actual machining is strongly required. In most cases, simulators are developed using a concept called a “voxel.” Voxel representation shapes 3D models, including tools and workpieces, with a set of minute cubes. However, voxel representation has a disadvantage in that it is difficult to accelerate the simulation. Therefore, this study used polygon representation instead of voxel representation. A cutting simulator was developed using the Vatti clipping algorithm from the computer graphics field.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127534535","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932123
Chi-Tho Cao, Van-Phu Do, B. Lee
This paper presents a method for automated wheel hub assembly which is important work in the industrial applications. A key requirements for this work are the positioning accuracy of manipulator in working space and the 6D object's pose determined by the 3D vision algorithms. A noncontact method using 3D scanner mounted on the end-effector robot is utilized for providing measurements of object pose in workspace. By controlling the end-effector of robot moving to the working space, the errors of the end-effector are compensated directly. Some experiments to pick up the wheel hub using an industrial robot were implemented to validate the assembly performance of the proposed method.
{"title":"Applying 3D Vision Sensing to an Industrial Robot for Vehicle Assembly under Noisy Environment","authors":"Chi-Tho Cao, Van-Phu Do, B. Lee","doi":"10.1109/ICMECT.2019.8932123","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932123","url":null,"abstract":"This paper presents a method for automated wheel hub assembly which is important work in the industrial applications. A key requirements for this work are the positioning accuracy of manipulator in working space and the 6D object's pose determined by the 3D vision algorithms. A noncontact method using 3D scanner mounted on the end-effector robot is utilized for providing measurements of object pose in workspace. By controlling the end-effector of robot moving to the working space, the errors of the end-effector are compensated directly. Some experiments to pick up the wheel hub using an industrial robot were implemented to validate the assembly performance of the proposed method.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125676932","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932147
M. Ahmed, Sufian Kuriry, M. Shafiullah, M. A. Abido
Microgrids are becoming very popular nowadays throughout the world as they utilize renewable energy resources (RER) effectively. Due to the intermittent nature of the dominant RER, different kind of energy storage systems are introduced to enhance reliability, stability, and performance of the microgrids. This paper presents an effective control and energy management strategy of a direct current (DC) microgrid employing hybrid energy storage systems (HESS). The main components of the modeled microgrid are intermittent RER, variable load, HESS, backup diesel generator, and power electronic converters. The current-mode controller manages to charge and discharge the HESS to overcome the intermittency of the RER and load variation. Besides, it proposes an effective energy management strategy that compensate for the energy generation shortage of the RER by utilizing the backup diesel generator. Furthermore, it maximizes the power generation from the photovoltaic (PV) plant employing maximum power point tracker (MPPT). Finally, this research verifies the effectiveness of the proposed system through simulation where the DC voltage level never crosses ± 5% limit under load variation and RER intermittency.
{"title":"DC Microgrid Energy Management with Hybrid Energy Storage Systems","authors":"M. Ahmed, Sufian Kuriry, M. Shafiullah, M. A. Abido","doi":"10.1109/ICMECT.2019.8932147","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932147","url":null,"abstract":"Microgrids are becoming very popular nowadays throughout the world as they utilize renewable energy resources (RER) effectively. Due to the intermittent nature of the dominant RER, different kind of energy storage systems are introduced to enhance reliability, stability, and performance of the microgrids. This paper presents an effective control and energy management strategy of a direct current (DC) microgrid employing hybrid energy storage systems (HESS). The main components of the modeled microgrid are intermittent RER, variable load, HESS, backup diesel generator, and power electronic converters. The current-mode controller manages to charge and discharge the HESS to overcome the intermittency of the RER and load variation. Besides, it proposes an effective energy management strategy that compensate for the energy generation shortage of the RER by utilizing the backup diesel generator. Furthermore, it maximizes the power generation from the photovoltaic (PV) plant employing maximum power point tracker (MPPT). Finally, this research verifies the effectiveness of the proposed system through simulation where the DC voltage level never crosses ± 5% limit under load variation and RER intermittency.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"233 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116962059","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932118
E. Najafi, Ronald M. Scheer
This paper proposes a well-structured way of designing and documenting a first robotics competition (FRC) robot or any other automated system for that matter. This is done for the following two reasons. First, create a better understanding of how to break down a mechatronic system and second, increase the ease of communication between different technical (and non-technical) fields. The system used in this work is a robot designed to compete in the FRC in 2017, designed by a group of students. The main objective of this system design, following the model-based approach, is to get familiar with the functionality of the robot. The design is documented in two ways: in a design tree and in AutomationML. The simulation results show that AutomationML diagrams provide a more clear structure and more detailed information compared to the design tree. However, neither of these options offers a solution for the physical integration of different subsystems.
{"title":"System Design of a First Robotic Competition Robot: A Model-Based Design Approach using AutomationML","authors":"E. Najafi, Ronald M. Scheer","doi":"10.1109/ICMECT.2019.8932118","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932118","url":null,"abstract":"This paper proposes a well-structured way of designing and documenting a first robotics competition (FRC) robot or any other automated system for that matter. This is done for the following two reasons. First, create a better understanding of how to break down a mechatronic system and second, increase the ease of communication between different technical (and non-technical) fields. The system used in this work is a robot designed to compete in the FRC in 2017, designed by a group of students. The main objective of this system design, following the model-based approach, is to get familiar with the functionality of the robot. The design is documented in two ways: in a design tree and in AutomationML. The simulation results show that AutomationML diagrams provide a more clear structure and more detailed information compared to the design tree. However, neither of these options offers a solution for the physical integration of different subsystems.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115777705","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932106
F. Aggogeri, Nicola Pellegrini, Claudio Taesi, M. Tiboni
This work presents an iterative methodology for reliability design of production equipment based on the diagnostic and prognostic approach. The proposed method starts with the FMECA analysis in order to identify the main critical components of mechanical systems (e.g. robotic cells, robots, automatic machines). The mitigation actions are selected evaluating a design review of the project or imposing a maintenance strategy by critical component. This selection is defined by the calculated risk (e.g. risk priority number) and the life cycle cost assessment of the production equipment. The analysis of failure causes may support in evaluating preventive or predictive techniques focused on physical or data driven models. The use of a general database that collects and shares information from systems/components already installed in the field permits to analyse life and performance data in real time in an integrated closed loop. This research is a part of PROGRAMS: PROGnostics based Reliability Analysis for Maintenance Scheduling, H2020-FOF-09-2017-767287.
{"title":"Design for Reliability of Robotic Systems Based on the Prognostic Approach","authors":"F. Aggogeri, Nicola Pellegrini, Claudio Taesi, M. Tiboni","doi":"10.1109/ICMECT.2019.8932106","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932106","url":null,"abstract":"This work presents an iterative methodology for reliability design of production equipment based on the diagnostic and prognostic approach. The proposed method starts with the FMECA analysis in order to identify the main critical components of mechanical systems (e.g. robotic cells, robots, automatic machines). The mitigation actions are selected evaluating a design review of the project or imposing a maintenance strategy by critical component. This selection is defined by the calculated risk (e.g. risk priority number) and the life cycle cost assessment of the production equipment. The analysis of failure causes may support in evaluating preventive or predictive techniques focused on physical or data driven models. The use of a general database that collects and shares information from systems/components already installed in the field permits to analyse life and performance data in real time in an integrated closed loop. This research is a part of PROGRAMS: PROGnostics based Reliability Analysis for Maintenance Scheduling, H2020-FOF-09-2017-767287.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132170535","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 : 2019-10-01DOI: 10.1109/ICMECT.2019.8932148
Ruqi Sun, W. Wong
Vibration damper is very useful in suppressing excessive vibrations in machines and dynamic structures. Viscous damper is the most commonly used vibration damper in industry but the damping coefficient of commercial viscous dampers is fixed once they are produced. It is useful in many industrial applications of vibration dampers if their damping coefficients can be adjusted easily in order to suit different damping requirements. In this paper, a tunable electromagnetic shunt damper (EMSD) with selfsensing capability is proposed, designed and tested experimentally. The proposed damper can provide a damping force proportional to its vibration velocity and therefore it can be used as an alternative of viscous damper. The damping coefficient of the proposed damper can be varied easily either manually or automatically. Both the damper coefficient and the vibration velocity of the proposed damper can be measured from its output voltage. The EMSD velocity sensing accuracy is comparable to a standard accelerometer and a laser displacement sensor.
{"title":"Vibration Control with a Tunable Self-Sensing Electromagnetic Shunt Damper","authors":"Ruqi Sun, W. Wong","doi":"10.1109/ICMECT.2019.8932148","DOIUrl":"https://doi.org/10.1109/ICMECT.2019.8932148","url":null,"abstract":"Vibration damper is very useful in suppressing excessive vibrations in machines and dynamic structures. Viscous damper is the most commonly used vibration damper in industry but the damping coefficient of commercial viscous dampers is fixed once they are produced. It is useful in many industrial applications of vibration dampers if their damping coefficients can be adjusted easily in order to suit different damping requirements. In this paper, a tunable electromagnetic shunt damper (EMSD) with selfsensing capability is proposed, designed and tested experimentally. The proposed damper can provide a damping force proportional to its vibration velocity and therefore it can be used as an alternative of viscous damper. The damping coefficient of the proposed damper can be varied easily either manually or automatically. Both the damper coefficient and the vibration velocity of the proposed damper can be measured from its output voltage. The EMSD velocity sensing accuracy is comparable to a standard accelerometer and a laser displacement sensor.","PeriodicalId":309525,"journal":{"name":"2019 23rd International Conference on Mechatronics Technology (ICMT)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134246502","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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