Pub Date : 2018-08-01DOI: 10.1109/MMAR.2018.8486097
A. Stief, J. Ottewill, J. Baranowski
A feature is a measured property of a monitored system. Feature extraction in condition monitoring requires domain knowledge about a system and its possible fault cases. To find the most sensitive features for fault patterns, one has to evaluate the relevancy of features. In this paper the authors use ReliefF, which is a K-nearest neighbors-based feature selection algorithm, to evaluate the features extracted from an induction motor dataset. The dataset contains data from eight different health states of an induction motor. Feature relevancy is calculated for each health state. The selected features are fed into a simple Bayesian binary classifier to calculate the most likely health state. The method provides insight into the relevance of features by sensor type and also by signal processing type. The evaluation of similarity among the selected features can help identify similar faults. The results obtained emphasize the importance of domain knowledge in the proper design of features. Furthermore, by considering experimental data obtained for multiple loading and noise conditions, the feature selection method indicates features which are best suited for diagnosing specific faults, regardless of external conditions. Such information can support the creation of robust monitoring systems.
{"title":"Relief F-Based Feature Ranking and Feature Selection for Monitoring Induction Motors","authors":"A. Stief, J. Ottewill, J. Baranowski","doi":"10.1109/MMAR.2018.8486097","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486097","url":null,"abstract":"A feature is a measured property of a monitored system. Feature extraction in condition monitoring requires domain knowledge about a system and its possible fault cases. To find the most sensitive features for fault patterns, one has to evaluate the relevancy of features. In this paper the authors use ReliefF, which is a K-nearest neighbors-based feature selection algorithm, to evaluate the features extracted from an induction motor dataset. The dataset contains data from eight different health states of an induction motor. Feature relevancy is calculated for each health state. The selected features are fed into a simple Bayesian binary classifier to calculate the most likely health state. The method provides insight into the relevance of features by sensor type and also by signal processing type. The evaluation of similarity among the selected features can help identify similar faults. The results obtained emphasize the importance of domain knowledge in the proper design of features. Furthermore, by considering experimental data obtained for multiple loading and noise conditions, the feature selection method indicates features which are best suited for diagnosing specific faults, regardless of external conditions. Such information can support the creation of robust monitoring systems.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117143025","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8485857
Katarzyna Wiechetek, R. Kaszynski
The paper presents a new concept of establishing the varying function parameters in order to reduce the duration of the transition processes. The optimization was conducted using particle swarm optimization algorithm (PSO). The main object of the research was 1st order element with two outputs: a low-pass and a high-pass. By selecting the right values of the parameters a better operation and considerably shorter settling times were achieved. After applying multiobjective optimization algorithm the system could adapt to more requirements at once.
{"title":"1st Order Nonstationary Element Optimization Using PSO Algorithm","authors":"Katarzyna Wiechetek, R. Kaszynski","doi":"10.1109/MMAR.2018.8485857","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8485857","url":null,"abstract":"The paper presents a new concept of establishing the varying function parameters in order to reduce the duration of the transition processes. The optimization was conducted using particle swarm optimization algorithm (PSO). The main object of the research was 1st order element with two outputs: a low-pass and a high-pass. By selecting the right values of the parameters a better operation and considerably shorter settling times were achieved. After applying multiobjective optimization algorithm the system could adapt to more requirements at once.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"20 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132501450","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8486122
P. Okoniewski, Sławomir Kocoń, J. Piskorowski
This paper presents a concept of implementing time-varying FIR narrow multi-band-stop filter for fast EMG measurements. The proposed system consists of a notch type filter with predefined time-varying coefficients and an IMU-based trigger to start the measurement of the muscle movement. The coefficients of the proposed filter are calculated according to the defined function in the selected time span. The use of an external trigger, which signals the moment of the muscle movement, allows to use the time-varying filter not only in the beginning of the measurement but also further during the test. The paper is an extension of the previous research in the field of time-varying filtering structures.
{"title":"Linear Time-Varying Multi-Notch FIR Filter for Fast EMG Measurements","authors":"P. Okoniewski, Sławomir Kocoń, J. Piskorowski","doi":"10.1109/MMAR.2018.8486122","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486122","url":null,"abstract":"This paper presents a concept of implementing time-varying FIR narrow multi-band-stop filter for fast EMG measurements. The proposed system consists of a notch type filter with predefined time-varying coefficients and an IMU-based trigger to start the measurement of the muscle movement. The coefficients of the proposed filter are calculated according to the defined function in the selected time span. The use of an external trigger, which signals the moment of the muscle movement, allows to use the time-varying filter not only in the beginning of the measurement but also further during the test. The paper is an extension of the previous research in the field of time-varying filtering structures.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131383060","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8485897
A. Kapilavai, A. Wolniakowski, Troels Bo Jørgensen, Anders P. Lindvig, T. Savarimuthu, N. Krüger
Gripper fingers design is a current and important problem in industrial robotics. Recently, advances have been made to replace the arduous manual trial-and-error design process with optimization methods based on dynamic simulations. In these approaches, the gripper fingers are parametrized and evaluated by simulating multiple grasp sets in order to obtain the quality score, which is subsequently optimized. The computational efficiency of this process depends on: (1) the choice of the scoring function that provides robust evaluation with minimal number of grasps, (2) the choice of optimization algorithm that converges to global optimum quickly and (3) the choice of optimization method and meta-parameters. In this paper, we present considerations pertaining to these three problems. We use the previously proposed gripper finger design and optimization methods for generating a finger cut-out for an asymmetrical object used in industrial assembly tasks. We suggest two new alignment quality scores and compare their efficiency with preexisting methods. In addition, compare the performance of two optimization methods (one local and one global) and find the meta-parameters for the local method.
{"title":"Efficient Evaluation and Optimization of Automated Gripper Finger Design for Industrial Robotic Applications","authors":"A. Kapilavai, A. Wolniakowski, Troels Bo Jørgensen, Anders P. Lindvig, T. Savarimuthu, N. Krüger","doi":"10.1109/MMAR.2018.8485897","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8485897","url":null,"abstract":"Gripper fingers design is a current and important problem in industrial robotics. Recently, advances have been made to replace the arduous manual trial-and-error design process with optimization methods based on dynamic simulations. In these approaches, the gripper fingers are parametrized and evaluated by simulating multiple grasp sets in order to obtain the quality score, which is subsequently optimized. The computational efficiency of this process depends on: (1) the choice of the scoring function that provides robust evaluation with minimal number of grasps, (2) the choice of optimization algorithm that converges to global optimum quickly and (3) the choice of optimization method and meta-parameters. In this paper, we present considerations pertaining to these three problems. We use the previously proposed gripper finger design and optimization methods for generating a finger cut-out for an asymmetrical object used in industrial assembly tasks. We suggest two new alignment quality scores and compare their efficiency with preexisting methods. In addition, compare the performance of two optimization methods (one local and one global) and find the meta-parameters for the local method.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126515266","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8486048
Adrian Wlodarczyk, A. Kowalczyk, J. Tarnawski
This paper presents a decentralized energy management system for a power microgrid, which integrates individual users, who own renewable energy sources and energy storages. The purpose of the system is to make optimal use of available resources to cover the electricity needs of the whole microgrid. Thanks to the energy exchange system, in addition to exchanges with the distribution network, the system also allows trades within the microgrid, between its participants. This way, users can get better offers for buying and selling energy than from the grid. The developed system uses linear optimization tasks to determine optimal power flows between microgrid's nodes. In order to do that, the system uses forecasted power generation profiles and consumer demand profiles, which come from prediction modules. Full decentralization of the system allowed for practically unlimited scalability compared to centralized systems. Decentralization also means better reliability and gives users the opportunity to make any changes to the optimizer. The system has been implemented in Python using free tools and libraries so that it can be implemented on any computer with an interpreter of that language.
{"title":"Decentralized Microgrid Energy Management System with Market-Based Energy Trade System","authors":"Adrian Wlodarczyk, A. Kowalczyk, J. Tarnawski","doi":"10.1109/MMAR.2018.8486048","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486048","url":null,"abstract":"This paper presents a decentralized energy management system for a power microgrid, which integrates individual users, who own renewable energy sources and energy storages. The purpose of the system is to make optimal use of available resources to cover the electricity needs of the whole microgrid. Thanks to the energy exchange system, in addition to exchanges with the distribution network, the system also allows trades within the microgrid, between its participants. This way, users can get better offers for buying and selling energy than from the grid. The developed system uses linear optimization tasks to determine optimal power flows between microgrid's nodes. In order to do that, the system uses forecasted power generation profiles and consumer demand profiles, which come from prediction modules. Full decentralization of the system allowed for practically unlimited scalability compared to centralized systems. Decentralization also means better reliability and gives users the opportunity to make any changes to the optimizer. The system has been implemented in Python using free tools and libraries so that it can be implemented on any computer with an interpreter of that language.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"296 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123184969","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8486075
M. Burak
Finding transient solutions in queuing systems is crucial in many applications, including of service system modeling. As many of such systems are Markovian, their natural description is that of a continuous-time Markov chain (CTMC), and uniformization is widely considered an efficient method for transient analysis of CTMCs. In this paper we present significant efficiency improvements to the standard uniformization algorithm when used for transient analysis of time-inhomogenous Markovian birth-and-death queuing models. We exploit some of the distinct properties of birth-and-death models in particular the structure of the generator matrix and the convergence properties of the model. Moreover, we utilize an example based on an realistic birth-and-death model of a call center in order to demonstrate that our proposal is especially advantageous for transient modeling of real service systems.
{"title":"Efficiency Improvements to Uniformization for Markovian Birth-and-Death Models","authors":"M. Burak","doi":"10.1109/MMAR.2018.8486075","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486075","url":null,"abstract":"Finding transient solutions in queuing systems is crucial in many applications, including of service system modeling. As many of such systems are Markovian, their natural description is that of a continuous-time Markov chain (CTMC), and uniformization is widely considered an efficient method for transient analysis of CTMCs. In this paper we present significant efficiency improvements to the standard uniformization algorithm when used for transient analysis of time-inhomogenous Markovian birth-and-death queuing models. We exploit some of the distinct properties of birth-and-death models in particular the structure of the generator matrix and the convergence properties of the model. Moreover, we utilize an example based on an realistic birth-and-death model of a call center in order to demonstrate that our proposal is especially advantageous for transient modeling of real service systems.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128155742","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8486102
Christian Thormann, A. Winkler
The paper investigates useful applications of RFID (Radio Frequency Identification) technology in combination with industrial robots, because these automation devices are very important in the context of the term Industry 4.0. In industrial automation, RFID transponders can be placed on tools and workpieces. Besides, the identification of objects, it is also possible to store information locally on the object. Such an object may be regarded as an intelligent object, because its supports the decentralization of decisions. The paper makes proposals about what kind of data can be stored in workpieces and how this information can be used to optimize the robot task. Room for improvement is found with respect to, e.g., the path accuracy of the robot motion, force/torque control and collision avoidance. Selected algorithms relating to the proposals are verified successfully by practical experiments.
{"title":"Optimization of Robot Tasks by Intelligent Objects Using RFID Technology","authors":"Christian Thormann, A. Winkler","doi":"10.1109/MMAR.2018.8486102","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486102","url":null,"abstract":"The paper investigates useful applications of RFID (Radio Frequency Identification) technology in combination with industrial robots, because these automation devices are very important in the context of the term Industry 4.0. In industrial automation, RFID transponders can be placed on tools and workpieces. Besides, the identification of objects, it is also possible to store information locally on the object. Such an object may be regarded as an intelligent object, because its supports the decentralization of decisions. The paper makes proposals about what kind of data can be stored in workpieces and how this information can be used to optimize the robot task. Room for improvement is found with respect to, e.g., the path accuracy of the robot motion, force/torque control and collision avoidance. Selected algorithms relating to the proposals are verified successfully by practical experiments.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125246823","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8485839
P. Ostalczyk
In the paper we propose a method of the variable-fractional-order (VFO) discrete-time linear system response calculation applied to the VFO RST/PID controllers response. To such controllers we cannot directly apply the commonly known one-sided $mathcal{Z}$-Transform method. Treating the VFO-PID controller as a special case of the RST controller we show that using classical methods we can derive the dynamical properties of the VFO-PID controller.
{"title":"Variable-, Fractional-Order RST/PID Controller Transient Characteristics Calculation","authors":"P. Ostalczyk","doi":"10.1109/MMAR.2018.8485839","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8485839","url":null,"abstract":"In the paper we propose a method of the variable-fractional-order (VFO) discrete-time linear system response calculation applied to the VFO RST/PID controllers response. To such controllers we cannot directly apply the commonly known one-sided $mathcal{Z}$-Transform method. Treating the VFO-PID controller as a special case of the RST controller we show that using classical methods we can derive the dynamical properties of the VFO-PID controller.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"42 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114297794","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8486066
Z. Kowalczuk, Marek S. Tatara
The paper addresses the issue of modeling the flow process in transmission pipelines. A base model used for numerical simulation is introduced. Under certain assumptions concerning steady state analysis, the differential equations describing the process are solved analytically for two cases: zero and nonzero inclination angle $alpha$. These equations describe a constant flow rate and a corresponding distribution of the pressure along the considered pipeline for both cases. The pipe length at which the pipeline is choking (the mass flow is equal zero) for given boundary pressures and inclination angle, is also derived. Convergence of the proposed solution for inclination angle $alpharightarrow 0$ to the zero tilt solution, is proved. An exemplary practical relationship based on obtained equations is provided as a 3D chart. A test pipeline with adjustable inclination angles of its selected parts is considered. The analytic solution for the effective angle is compared with numerical solutions, which show relevant discrepancies between the results obtained for nonzero angles. Clearly, the numerical solution for a straight pipeline (with the increasing number of segments) is convergent to the analytic solution. Moreover, up to 16°, the analytic approximation (using an effective inclination angle) is sufficient, and produces similar results as the numerical simulation.
{"title":"Analytical Steady-State Model of the Pipeline Flow Process","authors":"Z. Kowalczuk, Marek S. Tatara","doi":"10.1109/MMAR.2018.8486066","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8486066","url":null,"abstract":"The paper addresses the issue of modeling the flow process in transmission pipelines. A base model used for numerical simulation is introduced. Under certain assumptions concerning steady state analysis, the differential equations describing the process are solved analytically for two cases: zero and nonzero inclination angle $alpha$. These equations describe a constant flow rate and a corresponding distribution of the pressure along the considered pipeline for both cases. The pipe length at which the pipeline is choking (the mass flow is equal zero) for given boundary pressures and inclination angle, is also derived. Convergence of the proposed solution for inclination angle $alpharightarrow 0$ to the zero tilt solution, is proved. An exemplary practical relationship based on obtained equations is provided as a 3D chart. A test pipeline with adjustable inclination angles of its selected parts is considered. The analytic solution for the effective angle is compared with numerical solutions, which show relevant discrepancies between the results obtained for nonzero angles. Clearly, the numerical solution for a straight pipeline (with the increasing number of segments) is convergent to the analytic solution. Moreover, up to 16°, the analytic approximation (using an effective inclination angle) is sufficient, and produces similar results as the numerical simulation.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116091260","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 : 2018-08-01DOI: 10.1109/MMAR.2018.8485959
R. Beniak, T. Pyka
This paper discusses a comprehensive model of a mobile robot with a no-slip self-adjusting off-centered orientable wheel. Subsequently, by application of dynamic control, a comparison is made between two robot models: one accounting for the effect of the off-centered orientable wheel and another one excluding this effect. The aspects considered in the study include not only the error resulting from the drive along a given trajectory but also the consumption of energy of the compared models.
{"title":"The Effect of an Off-Centered Orientable Wheel on Motion Characteristics of a Mobile Robot","authors":"R. Beniak, T. Pyka","doi":"10.1109/MMAR.2018.8485959","DOIUrl":"https://doi.org/10.1109/MMAR.2018.8485959","url":null,"abstract":"This paper discusses a comprehensive model of a mobile robot with a no-slip self-adjusting off-centered orientable wheel. Subsequently, by application of dynamic control, a comparison is made between two robot models: one accounting for the effect of the off-centered orientable wheel and another one excluding this effect. The aspects considered in the study include not only the error resulting from the drive along a given trajectory but also the consumption of energy of the compared models.","PeriodicalId":201658,"journal":{"name":"2018 23rd International Conference on Methods & Models in Automation & Robotics (MMAR)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124308441","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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