Pub Date : 2017-05-19DOI: 10.1109/ICMSC.2017.7959450
Zhao Liu, Li-Bin Song, Ye Li, Bo-Zhao Pan
Taking a multi-joint robotic arm for example, the flexibility of links and joints are considered. The dynamic characteristics of the flexible robotic arm are studied based on finite element method and experimental modal analysis. The analysis results are compared. First, pre-stressed modal analysis of the flexcible robotic arm are carried out applying software ANSYS Workbench. The natural frequencies and corresponding modal shapes under first 6 orders are calculated. Then, the experimental modal analysis is performed by using LMS Test. Lab to obtain the former 6 ranks of natural frequencies, modal shapes and damping ratios. The results provides important parameters for the dynamic structure design of multi-joint flexible robotic arm. Finally, the pre-stressed modal analysis results are compared with the experimental results. A reliable basis for the research methods of dynamic characteristics is provided.
{"title":"Comparison of finite element and experimental modal analysis of multi-joint flexible robotic arm","authors":"Zhao Liu, Li-Bin Song, Ye Li, Bo-Zhao Pan","doi":"10.1109/ICMSC.2017.7959450","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959450","url":null,"abstract":"Taking a multi-joint robotic arm for example, the flexibility of links and joints are considered. The dynamic characteristics of the flexible robotic arm are studied based on finite element method and experimental modal analysis. The analysis results are compared. First, pre-stressed modal analysis of the flexcible robotic arm are carried out applying software ANSYS Workbench. The natural frequencies and corresponding modal shapes under first 6 orders are calculated. Then, the experimental modal analysis is performed by using LMS Test. Lab to obtain the former 6 ranks of natural frequencies, modal shapes and damping ratios. The results provides important parameters for the dynamic structure design of multi-joint flexible robotic arm. Finally, the pre-stressed modal analysis results are compared with the experimental results. A reliable basis for the research methods of dynamic characteristics is provided.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127847187","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959433
A. Khomich, M. Kozlova, E. Ashkinazi, V. Sedov, D. Sovyk, D. Vinogradov, P. Tsygankov
Micro/Nanocrystalline multilayer diamond coatings (DC) were produced using a microwave plasma-assisted CVD process from CH4/H2 (microcrystalline) and CH4/H2/N2 (nanocrystalline) gas mixtures and deposited on common tungsten carbide tools. High resolution surface electron microscopy, Raman spectroscopy, friction, wear and scratching resistance tests were performed to study properties of the four series of DC. It was shown that such multilayer DC not only display good adhesion and wear resistant properties, but also have high surface smoothness and extremely low friction coefficient.
{"title":"Microwave CVD deposition and properties of nano / microcrystalline diamond multilayer coatings on tungsten carbide cutting tools","authors":"A. Khomich, M. Kozlova, E. Ashkinazi, V. Sedov, D. Sovyk, D. Vinogradov, P. Tsygankov","doi":"10.1109/ICMSC.2017.7959433","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959433","url":null,"abstract":"Micro/Nanocrystalline multilayer diamond coatings (DC) were produced using a microwave plasma-assisted CVD process from CH4/H2 (microcrystalline) and CH4/H2/N2 (nanocrystalline) gas mixtures and deposited on common tungsten carbide tools. High resolution surface electron microscopy, Raman spectroscopy, friction, wear and scratching resistance tests were performed to study properties of the four series of DC. It was shown that such multilayer DC not only display good adhesion and wear resistant properties, but also have high surface smoothness and extremely low friction coefficient.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126058539","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959467
Abdel-Nasser Sharkawy, N. Aspragathos
In this paper, a comparative study of two methods are presented to determine the forward kinematics and Jacobian matrix for any serial manipulator, based on product of exponentials formula and unit dual quaternion algebra. This comparison is qualitative and particularly quantitative taken into account computational costs and memory requirements that are very critical in the manipulator control and real-time algorithms. For the first time the computational cost in determining the Jacobian matrix by using these two algorithms is compared. The two algorithms are applied to the 7-DOF Kuka Lightweight Robot using MATLAB and compared.
{"title":"A comparative study of two methods for forward kinematics and Jacobian matrix determination","authors":"Abdel-Nasser Sharkawy, N. Aspragathos","doi":"10.1109/ICMSC.2017.7959467","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959467","url":null,"abstract":"In this paper, a comparative study of two methods are presented to determine the forward kinematics and Jacobian matrix for any serial manipulator, based on product of exponentials formula and unit dual quaternion algebra. This comparison is qualitative and particularly quantitative taken into account computational costs and memory requirements that are very critical in the manipulator control and real-time algorithms. For the first time the computational cost in determining the Jacobian matrix by using these two algorithms is compared. The two algorithms are applied to the 7-DOF Kuka Lightweight Robot using MATLAB and compared.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127822963","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959504
A. Kazemi, Reza Behinfaraz, A. Ghiasi
Due to existence of many variables in large scale systems, design and implementation of controllers for such systems have been always important challenges. A common way to solve the problem is to obtain an equivalent reduced order model of the system in the first step and then, design a suitable controller. In this paper model reduction of large scale systems based on multi objective particle swarm optimization is presented. According to the required order of reduction, proper reduced system is obtained. For high precision in modeling, multi objective particle swarm optimization is used. In this algorithm, multi objects regarding to properties of system response are solved. It is shown that proposed approach is very useful tool for model reduction of large scale systems. Simulation examples prove this claim.
{"title":"Accurate model reduction of large scale systems using adaptive multi-objective particle swarm optimization algorithm","authors":"A. Kazemi, Reza Behinfaraz, A. Ghiasi","doi":"10.1109/ICMSC.2017.7959504","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959504","url":null,"abstract":"Due to existence of many variables in large scale systems, design and implementation of controllers for such systems have been always important challenges. A common way to solve the problem is to obtain an equivalent reduced order model of the system in the first step and then, design a suitable controller. In this paper model reduction of large scale systems based on multi objective particle swarm optimization is presented. According to the required order of reduction, proper reduced system is obtained. For high precision in modeling, multi objective particle swarm optimization is used. In this algorithm, multi objects regarding to properties of system response are solved. It is shown that proposed approach is very useful tool for model reduction of large scale systems. Simulation examples prove this claim.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117216697","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959442
Yue-neng Yang, Ye Yan, Zhenlong Zhu, Xu Huang
This paper proposes a fuzzy gain scheduling backstepping sliding mode control (FGS-BSMC) approach for a class of uncertain strict-feedback nonlinear system. First, system description and problem formulation is given. Second, the FGS-BSMC is proposed to design the controller for the strict-feedback nonlinear system. A sliding mode control (SMC) is employed to construct the backstepping sliding mode control (BSMC) approach for design flexibility of backstepping control and robustness of SMC. In order to decrease chattering result from SMC, a fuzzy logic system (FLS) is designed to construct the FGS-SMC, in which the gain of sign function can be scheduled adaptively according to the fuzzy rules. Finally, a verification example is given to demonstrate the effectiveness the proposed FGS-BSMC. Simulation results illustrate that the FGS-BSMC decreases chattering effectively and has better control performance against BSMC.
{"title":"Chattering-free sliding mode control for strict-feedback nonlinear systems using back-stepping technique","authors":"Yue-neng Yang, Ye Yan, Zhenlong Zhu, Xu Huang","doi":"10.1109/ICMSC.2017.7959442","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959442","url":null,"abstract":"This paper proposes a fuzzy gain scheduling backstepping sliding mode control (FGS-BSMC) approach for a class of uncertain strict-feedback nonlinear system. First, system description and problem formulation is given. Second, the FGS-BSMC is proposed to design the controller for the strict-feedback nonlinear system. A sliding mode control (SMC) is employed to construct the backstepping sliding mode control (BSMC) approach for design flexibility of backstepping control and robustness of SMC. In order to decrease chattering result from SMC, a fuzzy logic system (FLS) is designed to construct the FGS-SMC, in which the gain of sign function can be scheduled adaptively according to the fuzzy rules. Finally, a verification example is given to demonstrate the effectiveness the proposed FGS-BSMC. Simulation results illustrate that the FGS-BSMC decreases chattering effectively and has better control performance against BSMC.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124620164","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959436
A. Brom, E. Gorlacheva, I. Pekshev
Additive manufacturing technologies or technologies of ply assembly method to some extent creates transfer conditions to manufacturing technologies of new generation. They dramatically change the existing techno-economic paradigm and lead to reconfiguration of the whole production cycle. The analysis of time and value expenditures for small IoT production of unmanned aerial vehicle, manufactured by means of traditional and additive manufacturing technologies allowed evaluating perspectives of additive manufacturing implementation. The article will be of use to professionals in engineering, innovation management, for research, teaching and private study purposes.
{"title":"The perspectives of additive manufacturing technologies implementation in mass production of short range unmanned aerial vehicle","authors":"A. Brom, E. Gorlacheva, I. Pekshev","doi":"10.1109/ICMSC.2017.7959436","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959436","url":null,"abstract":"Additive manufacturing technologies or technologies of ply assembly method to some extent creates transfer conditions to manufacturing technologies of new generation. They dramatically change the existing techno-economic paradigm and lead to reconfiguration of the whole production cycle. The analysis of time and value expenditures for small IoT production of unmanned aerial vehicle, manufactured by means of traditional and additive manufacturing technologies allowed evaluating perspectives of additive manufacturing implementation. The article will be of use to professionals in engineering, innovation management, for research, teaching and private study purposes.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131827994","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959438
A. Dovgyallo, V. Kudinov, D. A. Shestakova
The way of heat regeneration in the cycle of internal combustion engine (ICE) is suggested. An expression for thermal coefficient of performance (COP) is derived which considers the differences in polytropic coefficient of expansion and compression processes, the level of heat regeneration as well as different compression and expansion ratios in compression and expansion cylinders. The values of this COP for different values of compression and expansion ratios in regeneration degree of 0.5…0.8 are received considering real values of heat capacities and polytropic coefficients in compression and expansion processes. The results were of this cycle calculation were compared with basic Otto cycle values.
{"title":"Working cycle analysis of the internal combustion engine with heat regeneration","authors":"A. Dovgyallo, V. Kudinov, D. A. Shestakova","doi":"10.1109/ICMSC.2017.7959438","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959438","url":null,"abstract":"The way of heat regeneration in the cycle of internal combustion engine (ICE) is suggested. An expression for thermal coefficient of performance (COP) is derived which considers the differences in polytropic coefficient of expansion and compression processes, the level of heat regeneration as well as different compression and expansion ratios in compression and expansion cylinders. The values of this COP for different values of compression and expansion ratios in regeneration degree of 0.5…0.8 are received considering real values of heat capacities and polytropic coefficients in compression and expansion processes. The results were of this cycle calculation were compared with basic Otto cycle values.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131196163","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 : 2017-05-19DOI: 10.1109/ICMSC.2017.7959507
Noman Naseer, Hammad Nazeer
In this paper, we propose a system that is capable of automatically differentiating between normal and abnormal heartbeats of patients using signals acquired from electrocardiography (ECG). The components of the ECG signals, that are PQRST intervals, were studied to acquire features for classification. Different time intervals of p-wave, QRS complex and t-wave were used as features. These features were fed to a linear discriminant analysis to classify the normal and abnormal heartbeats. The classification accuracy was above 80% on average. The results demonstrate the feasibility of development of a machine that is able to automatically detect all potential heart related diseases that can be identified from ECG signals manually.
{"title":"Classification of normal and abnormal ECG signals based on their PQRST intervals","authors":"Noman Naseer, Hammad Nazeer","doi":"10.1109/ICMSC.2017.7959507","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959507","url":null,"abstract":"In this paper, we propose a system that is capable of automatically differentiating between normal and abnormal heartbeats of patients using signals acquired from electrocardiography (ECG). The components of the ECG signals, that are PQRST intervals, were studied to acquire features for classification. Different time intervals of p-wave, QRS complex and t-wave were used as features. These features were fed to a linear discriminant analysis to classify the normal and abnormal heartbeats. The classification accuracy was above 80% on average. The results demonstrate the feasibility of development of a machine that is able to automatically detect all potential heart related diseases that can be identified from ECG signals manually.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116703536","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 : 2017-05-01DOI: 10.1109/ICMSC.2017.7959487
Ming Yang, Zhimin Chen, Yutao Wang, Haoyu Zhang
Measurement of solid volume concentration in gas- solid two-phase flow is based on the prerequisite of invariable solid medium dielectric constant, but in the existing industrial measurement, measuring error is caused as a result of neglecting the variation of solid medium dielectric constant. In order to solve this problem, a measuring method which can compensate solid medium dielectric constant is proposed. In the new measuring method, two capacitance sensors are combined: the compensatory capacitance sensor and the measuring capacitance sensor. The compensatory capacitance sensor has a fixed solid volume concentration, so the output can reflect changes of solid dielectric constant and offer a compensation data. The measuring capacitance sensor is used to measure solid volume concentration after the compensation. A mathematical model is built to illustrate how to compensate dielectric constant with the compensation data. The mathematical model is built on the foundation of output characteristics of capacitance sensors, which is studied at the start of the paper. Experiments are carried out to evaluate the performance of the existing and new measuring methods. Experimental results show that when the solid phase dielectric constant varies, relative error is greater than 40% if the existing method is used while it is about 6% if the new method is used. Using the new measuring method can compensate solid phase dielectric constant online and increase the accuracy of concentration measurement.
{"title":"Research on a measuring method with the function of compensating dielectric constant","authors":"Ming Yang, Zhimin Chen, Yutao Wang, Haoyu Zhang","doi":"10.1109/ICMSC.2017.7959487","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959487","url":null,"abstract":"Measurement of solid volume concentration in gas- solid two-phase flow is based on the prerequisite of invariable solid medium dielectric constant, but in the existing industrial measurement, measuring error is caused as a result of neglecting the variation of solid medium dielectric constant. In order to solve this problem, a measuring method which can compensate solid medium dielectric constant is proposed. In the new measuring method, two capacitance sensors are combined: the compensatory capacitance sensor and the measuring capacitance sensor. The compensatory capacitance sensor has a fixed solid volume concentration, so the output can reflect changes of solid dielectric constant and offer a compensation data. The measuring capacitance sensor is used to measure solid volume concentration after the compensation. A mathematical model is built to illustrate how to compensate dielectric constant with the compensation data. The mathematical model is built on the foundation of output characteristics of capacitance sensors, which is studied at the start of the paper. Experiments are carried out to evaluate the performance of the existing and new measuring methods. Experimental results show that when the solid phase dielectric constant varies, relative error is greater than 40% if the existing method is used while it is about 6% if the new method is used. Using the new measuring method can compensate solid phase dielectric constant online and increase the accuracy of concentration measurement.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116394860","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 : 2017-05-01DOI: 10.1109/ICMSC.2017.7959463
Ebru Senyigit Sinekli, Ramazan Coban
In this study, a dynamic integral sliding mode control is put forward to control the speed of an electromechanical system. The dynamic integral sliding mode control is proposed to make sliding mode control aspects better and remove undesirable chattering effects. Lyapunov theorem is applied to guarantee the system's stability. The system under parameter uncertainty is considered close to the real world industrial systems. The experimental results obtained from the sliding mode control are compared with the experimental results of dynamic integral sliding mode control under parameter uncertainty. Experimental results verify that dynamic integral sliding mode control method provides preferable tracking performance, overcomes chattering, and has better raising time, smaller settling time, and no overshoot. It is robust with respect to parameter variations compared to the sliding mode control.
{"title":"Dynamic integral sliding mode control of an electromechanical system","authors":"Ebru Senyigit Sinekli, Ramazan Coban","doi":"10.1109/ICMSC.2017.7959463","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959463","url":null,"abstract":"In this study, a dynamic integral sliding mode control is put forward to control the speed of an electromechanical system. The dynamic integral sliding mode control is proposed to make sliding mode control aspects better and remove undesirable chattering effects. Lyapunov theorem is applied to guarantee the system's stability. The system under parameter uncertainty is considered close to the real world industrial systems. The experimental results obtained from the sliding mode control are compared with the experimental results of dynamic integral sliding mode control under parameter uncertainty. Experimental results verify that dynamic integral sliding mode control method provides preferable tracking performance, overcomes chattering, and has better raising time, smaller settling time, and no overshoot. It is robust with respect to parameter variations compared to the sliding mode control.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129246847","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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