Pub Date : 2014-12-11DOI: 10.1109/CCA.2014.6981332
Andrea Perizzato, M. Farina, L. Piroddi, R. Scattolini, E. Osto
Defective bearings can jeopardize the good functioning of rotating machinery. In this work we employ multivariate statistical techniques to monitor a drive reducer in a hot steel rolling mill, with the aim of detecting incipient defects associated to rolling bearings. Several vibration signals are measured and processed for this purpose, as well as the current absorbed by the motor driving the mill. A normal condition reference model is first constructed and deviations from it are detected by monitoring T2 statistics. Classical bearing defect models are employed to test the fault detection capabilities of the method.
{"title":"Fault detection of bearings in a drive reducer of a hot steel rolling mill","authors":"Andrea Perizzato, M. Farina, L. Piroddi, R. Scattolini, E. Osto","doi":"10.1109/CCA.2014.6981332","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981332","url":null,"abstract":"Defective bearings can jeopardize the good functioning of rotating machinery. In this work we employ multivariate statistical techniques to monitor a drive reducer in a hot steel rolling mill, with the aim of detecting incipient defects associated to rolling bearings. Several vibration signals are measured and processed for this purpose, as well as the current absorbed by the motor driving the mill. A normal condition reference model is first constructed and deviations from it are detected by monitoring T2 statistics. Classical bearing defect models are employed to test the fault detection capabilities of the method.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127789529","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981462
Guillaume Allibert, D. Abeywardena, Moses Bangura, R. Mahony
A key requirement for effective control of quadrotor vehicles is estimation of both attitude and linear velocity. Recent work has demonstrated that it is possible to measure horizontal velocities of a quadrotor vehicle from strap-down ac-celerometers along with a system model. In this paper we extend this to full body-fixed-frame velocity measurement by exploiting recent work in aerodynamic modeling of rotor performance and measurements of mechanical power supplied to the rotor hub. We use these measurements in a combined attitude and velocity nonlinear observer design to jointly estimate attitude and body-fixed-frame linear velocity. Almost global asymptotic stability of the resulting system is demonstrated using Lyapunov analysis of the resulting error system. In the current work, we ignore bias and leave it for future work. The performance of the observer is verified by simulation results.
{"title":"Estimating body-fixed frame velocity and attitude from inertial measurements for a quadrotor vehicle","authors":"Guillaume Allibert, D. Abeywardena, Moses Bangura, R. Mahony","doi":"10.1109/CCA.2014.6981462","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981462","url":null,"abstract":"A key requirement for effective control of quadrotor vehicles is estimation of both attitude and linear velocity. Recent work has demonstrated that it is possible to measure horizontal velocities of a quadrotor vehicle from strap-down ac-celerometers along with a system model. In this paper we extend this to full body-fixed-frame velocity measurement by exploiting recent work in aerodynamic modeling of rotor performance and measurements of mechanical power supplied to the rotor hub. We use these measurements in a combined attitude and velocity nonlinear observer design to jointly estimate attitude and body-fixed-frame linear velocity. Almost global asymptotic stability of the resulting system is demonstrated using Lyapunov analysis of the resulting error system. In the current work, we ignore bias and leave it for future work. The performance of the observer is verified by simulation results.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127963924","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981402
B. J. T. Binder, D. Kufoalor, A. Pavlov, T. Johansen
Electric Submersible Pumps (ESPs) can be installed in oil wells to create artificial lift, in order to increase recovery from the reservoir, and boost the production rate. A Model Predictive Controller (MPC) for an ESP, based on linearized models, is developed and designed using SEPTIC (Statoil's in-house software tool for MPC), and implemented on a Programmable Logic Controller (PLC). Automatic code generators have been utilized to generate an application-specific MPC controller in ANSI C code. Hardware-in-the-loop simulation results show that the control performance of the PLC implementation is comparable to the original SEPTIC controller.
{"title":"Embedded Model Predictive Control for an Electric Submersible Pump on a Programmable Logic Controller","authors":"B. J. T. Binder, D. Kufoalor, A. Pavlov, T. Johansen","doi":"10.1109/CCA.2014.6981402","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981402","url":null,"abstract":"Electric Submersible Pumps (ESPs) can be installed in oil wells to create artificial lift, in order to increase recovery from the reservoir, and boost the production rate. A Model Predictive Controller (MPC) for an ESP, based on linearized models, is developed and designed using SEPTIC (Statoil's in-house software tool for MPC), and implemented on a Programmable Logic Controller (PLC). Automatic code generators have been utilized to generate an application-specific MPC controller in ANSI C code. Hardware-in-the-loop simulation results show that the control performance of the PLC implementation is comparable to the original SEPTIC controller.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129012654","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981482
J. Emery, B. Dehning, C. Pereira, J. L. S. Blasco, S. Cantin, M. Tognolini, B. Schneider, K. Henzer, M. Starkier
The Beam Instrumentation group of the European Organization for Nuclear Research (CERN) has been developing an instrument called the Beam Wire Scanner (BWS) for the past few years. This system is used to measure the size of proton beams in the Large Hadron Collider (LHC) and its injector chain. An electro-mechanical system moves a very thin wire of 30 μm through the particle beam and measures the induced radiation losses generated by this interaction. The actuator, based on a Permanent Magnet Synchronous Motor (PMSM), a solid rotor resolver and an in-house designed high precision optical encoder are located in underground installations and have to cope with large irradiation levels. Another difference with respect to its predecessors is the placement of all moving parts in the vacuum. The control electronics is situated far away from the beam tunnels to minimize the destructive impact of ionizing particles. Challenges arise from the long distance between these two parts, up to 250 meters, and the high scanning speed of the wire of up to 20 ms1, with a target position accuracy as low as 5 μm rms. This paper describes the challenges of the BWS design, details the current status and introduces the philosophy of its conception to the IEEE control application community.
{"title":"A fast and accurate wire scanner instrument for the CERN accelerators to cope with severe environmental constraints and an increased demand for availability","authors":"J. Emery, B. Dehning, C. Pereira, J. L. S. Blasco, S. Cantin, M. Tognolini, B. Schneider, K. Henzer, M. Starkier","doi":"10.1109/CCA.2014.6981482","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981482","url":null,"abstract":"The Beam Instrumentation group of the European Organization for Nuclear Research (CERN) has been developing an instrument called the Beam Wire Scanner (BWS) for the past few years. This system is used to measure the size of proton beams in the Large Hadron Collider (LHC) and its injector chain. An electro-mechanical system moves a very thin wire of 30 μm through the particle beam and measures the induced radiation losses generated by this interaction. The actuator, based on a Permanent Magnet Synchronous Motor (PMSM), a solid rotor resolver and an in-house designed high precision optical encoder are located in underground installations and have to cope with large irradiation levels. Another difference with respect to its predecessors is the placement of all moving parts in the vacuum. The control electronics is situated far away from the beam tunnels to minimize the destructive impact of ionizing particles. Challenges arise from the long distance between these two parts, up to 250 meters, and the high scanning speed of the wire of up to 20 ms1, with a target position accuracy as low as 5 μm rms. This paper describes the challenges of the BWS design, details the current status and introduces the philosophy of its conception to the IEEE control application community.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122220244","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981540
Miguel Parada Contzen, J. Raisch
Switched linear systems are present in a wide range of engineering applications. Even though they have been systematically addressed in the past, stability conditions are usually conservative and often valid for special cases only. In this paper we propose a novel approach using polytopic systems theory, which allows us to treat general switched linear systems by LMI tools. We propose an alternative proof for the well-known common quadratic Lyapunov stability condition. This proof is then extended to less restrictive stability conditions.
{"title":"A polytopic approach to switched linear systems","authors":"Miguel Parada Contzen, J. Raisch","doi":"10.1109/CCA.2014.6981540","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981540","url":null,"abstract":"Switched linear systems are present in a wide range of engineering applications. Even though they have been systematically addressed in the past, stability conditions are usually conservative and often valid for special cases only. In this paper we propose a novel approach using polytopic systems theory, which allows us to treat general switched linear systems by LMI tools. We propose an alternative proof for the well-known common quadratic Lyapunov stability condition. This proof is then extended to less restrictive stability conditions.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116648981","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981601
W. Lombardi, M. Altieri, Y. Akgul, D. Puschini, S. Lesecq
During the last decade, Dynamic Voltage and Frequency Scaling (DVFS) techniques have been widely proposed to improve integrated circuit power efficiency. In the present work, an optimal control is proposed to jointly control the voltage and frequency transient periods of both the supply voltage and clock frequency actuators. This control law is based on a multivariable optimal controller for trajectory tracking with an integrator. At the same time it ensures the global system stability and promotes design reuse, the proposed controller also increases the system performance during the transition. Simulation results with MatLab Simulink are also provided to show the effectiveness of the technique. Moreover, Register Transfer Level (RTL) simulation shows that the proposed control can be implemented in hardware within a chip.
{"title":"Multivariable voltage and frequency control for DVFS management","authors":"W. Lombardi, M. Altieri, Y. Akgul, D. Puschini, S. Lesecq","doi":"10.1109/CCA.2014.6981601","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981601","url":null,"abstract":"During the last decade, Dynamic Voltage and Frequency Scaling (DVFS) techniques have been widely proposed to improve integrated circuit power efficiency. In the present work, an optimal control is proposed to jointly control the voltage and frequency transient periods of both the supply voltage and clock frequency actuators. This control law is based on a multivariable optimal controller for trajectory tracking with an integrator. At the same time it ensures the global system stability and promotes design reuse, the proposed controller also increases the system performance during the transition. Simulation results with MatLab Simulink are also provided to show the effectiveness of the technique. Moreover, Register Transfer Level (RTL) simulation shows that the proposed control can be implemented in hardware within a chip.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117007288","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981452
A. Dòria-Cerezo, J. Acosta, Á. Castaño, E. Fossas
The control design proposed here is based on a general framework of control of nonlinear systems with state-&-input constraints, recently proposed by some of the authors in [1] (summary available in [2]). Thus, this is part of a series of real applications to support the theoretical results. In particular, here the result is applied to the problem of dynamic positioning of ships with nonlinear position constraints. The solution proposed solves the problem by means of diffeomorphisms which transform the nonlinear constrained control problem into an unconstrained one. A real scenario of the ship crossing through a strait has been tested in a realistic simulator developed by a world leader shipbuilding company [3]. As a plus, the solution proposed could alleviate the computational burden of motion planning in dynamic positioning of ships.
{"title":"Nonlinear state-constrained control. Application to the dynamic positioning of ships","authors":"A. Dòria-Cerezo, J. Acosta, Á. Castaño, E. Fossas","doi":"10.1109/CCA.2014.6981452","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981452","url":null,"abstract":"The control design proposed here is based on a general framework of control of nonlinear systems with state-&-input constraints, recently proposed by some of the authors in [1] (summary available in [2]). Thus, this is part of a series of real applications to support the theoretical results. In particular, here the result is applied to the problem of dynamic positioning of ships with nonlinear position constraints. The solution proposed solves the problem by means of diffeomorphisms which transform the nonlinear constrained control problem into an unconstrained one. A real scenario of the ship crossing through a strait has been tested in a realistic simulator developed by a world leader shipbuilding company [3]. As a plus, the solution proposed could alleviate the computational burden of motion planning in dynamic positioning of ships.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132583028","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981558
S. E. Benattia, S. Tebbani, D. Dumur, D. Selișteanu
This paper deals with the design of a predictive control law for microalgae culture process to regulate the biomass concentration at a chosen setpoint. However, the performances of the Nonlinear Model Predictive Controller usually decrease when the true plant evolution deviates significantly from that predicted by the model. Thus, a robust criterion under model's parameters uncertainties is considered, implying solving a min-max optimization problem. In order to reduce the computational burden and complexity induced by this formulation, a sensitivity analysis is carried out to determine the most influential parameters which will be considered in the optimization step. The proposed approach is validated in simulation and numerical results are given to illustrate its efficiency for setpoint tracking in the presence of parameters uncertainties.
{"title":"Robust Nonlinear Model Predictive Controller based on sensitivity analysis — Application to a continuous photobioreactor","authors":"S. E. Benattia, S. Tebbani, D. Dumur, D. Selișteanu","doi":"10.1109/CCA.2014.6981558","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981558","url":null,"abstract":"This paper deals with the design of a predictive control law for microalgae culture process to regulate the biomass concentration at a chosen setpoint. However, the performances of the Nonlinear Model Predictive Controller usually decrease when the true plant evolution deviates significantly from that predicted by the model. Thus, a robust criterion under model's parameters uncertainties is considered, implying solving a min-max optimization problem. In order to reduce the computational burden and complexity induced by this formulation, a sensitivity analysis is carried out to determine the most influential parameters which will be considered in the optimization step. The proposed approach is validated in simulation and numerical results are given to illustrate its efficiency for setpoint tracking in the presence of parameters uncertainties.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132264129","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981457
I. Furtat, E. Tupichin
The paper describes the robust algorithm for nonlinear SISO plants under parametric uncertainties and external disturbances. Unlike other known results it is shown that in the control system only one filter of dimension n is used, where n is a dynamical order of a plant. Calculation derivatives of stabilizing control signals are realized by first order observers. It allows simplifying the analytical calculation of the control system. Algorithm provides compensation of parametric uncertainties and external disturbances with required accuracy. Simulations are illustrated an efficiency of proposed scheme for an unstable nonlinear plant and control of a magnetic levitation system.
{"title":"Control of nonlinear plant based on modified robust backstepping algorithm","authors":"I. Furtat, E. Tupichin","doi":"10.1109/CCA.2014.6981457","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981457","url":null,"abstract":"The paper describes the robust algorithm for nonlinear SISO plants under parametric uncertainties and external disturbances. Unlike other known results it is shown that in the control system only one filter of dimension n is used, where n is a dynamical order of a plant. Calculation derivatives of stabilizing control signals are realized by first order observers. It allows simplifying the analytical calculation of the control system. Algorithm provides compensation of parametric uncertainties and external disturbances with required accuracy. Simulations are illustrated an efficiency of proposed scheme for an unstable nonlinear plant and control of a magnetic levitation system.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132192032","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 : 2014-12-11DOI: 10.1109/CCA.2014.6981517
P. Odgaard, A. Nejad
Reliability and availability of modern wind turbines are of increasing importance, for two reasons. The first is due to the fact that power grids around in the world depends at a higher and higher degree on wind energy, and the second is the importance of lowering Cost of Energy of the wind turbines. One of the critical components in modern wind turbines is the gearbox. Failures in the gearbox are costly both due to the cost of the gearbox itself, but also due to lost power generation during repair of it. Wind turbine gearboxes are consequently monitored by condition monitoring systems operating in parallel with the control system, and also uses additional sensors measuring different accelerations and noises, etc. In this paper gearbox data from high fidelity gearbox model of a 750 kW wind turbine gearbox, simulated with and without faults are used to shown the potential of frequency based detection schemes applied on measurements normally available in a wind controller system. This paper shows that two given faults in the gearbox can be detected using a frequency based detection approach applied to sensor signals normally available in the wind turbine control system. This means that gearbox condition monitoring/ fault detection could be included in the standard control system, which potentially can remove the cost of the additional condition monitoring system and the additional sensors used in it.
{"title":"Frequency based wind turbine gearbox fault detection applied to a 750 kW wind turbine","authors":"P. Odgaard, A. Nejad","doi":"10.1109/CCA.2014.6981517","DOIUrl":"https://doi.org/10.1109/CCA.2014.6981517","url":null,"abstract":"Reliability and availability of modern wind turbines are of increasing importance, for two reasons. The first is due to the fact that power grids around in the world depends at a higher and higher degree on wind energy, and the second is the importance of lowering Cost of Energy of the wind turbines. One of the critical components in modern wind turbines is the gearbox. Failures in the gearbox are costly both due to the cost of the gearbox itself, but also due to lost power generation during repair of it. Wind turbine gearboxes are consequently monitored by condition monitoring systems operating in parallel with the control system, and also uses additional sensors measuring different accelerations and noises, etc. In this paper gearbox data from high fidelity gearbox model of a 750 kW wind turbine gearbox, simulated with and without faults are used to shown the potential of frequency based detection schemes applied on measurements normally available in a wind controller system. This paper shows that two given faults in the gearbox can be detected using a frequency based detection approach applied to sensor signals normally available in the wind turbine control system. This means that gearbox condition monitoring/ fault detection could be included in the standard control system, which potentially can remove the cost of the additional condition monitoring system and the additional sensors used in it.","PeriodicalId":205599,"journal":{"name":"2014 IEEE Conference on Control Applications (CCA)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127913115","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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