Pub Date : 2018-08-01DOI: 10.1109/CCTA.2018.8511507
J. Bang, S. Choi, Young-kwan Ko, Tae Soo Kim, S. Kim
In this paper, an engine clutch engagement control for hybrid electric vehicles (HEVs) with a transmission mounted electric device (TMED) will be dealt with. In general, the engine of the HEVs repeatedly turns on and off in even one driving cycle, and when the engine turns on, the fast synchronization of the engine speed and the motor speed which is equal to the transmission input speed is very important to transfer the engine power to the driving wheel without a shock during the engagement for better fuel economy and drivability feeling. A hybrid starter generator (HSG) at HEVs is connected into the engine by a pulley, and the engine speed can be controlled by the HSG. When the engine starts to turn on, the engine torque is very unstable, and unpredictable and then the control of the engine speed by HSG is very difficult. The suggested method consists of a disturbance observer and a tracking controller which is composed of a feedback control and a feedforward control. The disturbance observer estimates and compensates a model uncertainty and disturbances such as an engine torque, a friction torque, and so on. The feedback and feedforward control are used for the engine speed to follow a target speed. Then the suggested method is very robust to the model uncertainty, and the disturbances, and then the fast engagement of the engine clutch without a shock is possible. For the effectiveness of the suggested method, the experimental results by TMED HEVs are shown.
{"title":"The Engine Clutch Engagement Control for Hybrid Electric Vehicles","authors":"J. Bang, S. Choi, Young-kwan Ko, Tae Soo Kim, S. Kim","doi":"10.1109/CCTA.2018.8511507","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511507","url":null,"abstract":"In this paper, an engine clutch engagement control for hybrid electric vehicles (HEVs) with a transmission mounted electric device (TMED) will be dealt with. In general, the engine of the HEVs repeatedly turns on and off in even one driving cycle, and when the engine turns on, the fast synchronization of the engine speed and the motor speed which is equal to the transmission input speed is very important to transfer the engine power to the driving wheel without a shock during the engagement for better fuel economy and drivability feeling. A hybrid starter generator (HSG) at HEVs is connected into the engine by a pulley, and the engine speed can be controlled by the HSG. When the engine starts to turn on, the engine torque is very unstable, and unpredictable and then the control of the engine speed by HSG is very difficult. The suggested method consists of a disturbance observer and a tracking controller which is composed of a feedback control and a feedforward control. The disturbance observer estimates and compensates a model uncertainty and disturbances such as an engine torque, a friction torque, and so on. The feedback and feedforward control are used for the engine speed to follow a target speed. Then the suggested method is very robust to the model uncertainty, and the disturbances, and then the fast engagement of the engine clutch without a shock is possible. For the effectiveness of the suggested method, the experimental results by TMED HEVs are shown.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"14 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":"122222616","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/CCTA.2018.8511531
A. Gambier, Y. Y. Nazaruddin
The main control strategy of three-bladed, variable-speed, horizontal-axis large-sized wind turbines, in case of over rated wind speed is based on the equal actuation of the all three blades. In addition to this collective pitch control (CPC), the provided pitch angles can be slightly individually modified according to measurements of the root bending moments (IPC, individual pitch control) in order to mitigate loads. Finally, the pitch actuation produces additional tower oscillations that will require an active tower damping control (ATDC). All these control loops are usually PID-based. The present work describes the results obtained from a nonlinear PID control (NPID) approach for the pitch system of a large wind turbine. Nonlinear PID approaches based on hyperbolic secant functions are used for the CPC, ICP and ATDC, respectively. As simulation platform, the 5-MW reference turbine developed by NREL and the software FAST are used. Results show that the NPID approach can provide significant improvements in the control performance in comparison to the classic control approach, in particular when the wind speed goes far from its rated value.
{"title":"Nonlinear PID Control for Pitch Systems of Large Wind Energy Converters","authors":"A. Gambier, Y. Y. Nazaruddin","doi":"10.1109/CCTA.2018.8511531","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511531","url":null,"abstract":"The main control strategy of three-bladed, variable-speed, horizontal-axis large-sized wind turbines, in case of over rated wind speed is based on the equal actuation of the all three blades. In addition to this collective pitch control (CPC), the provided pitch angles can be slightly individually modified according to measurements of the root bending moments (IPC, individual pitch control) in order to mitigate loads. Finally, the pitch actuation produces additional tower oscillations that will require an active tower damping control (ATDC). All these control loops are usually PID-based. The present work describes the results obtained from a nonlinear PID control (NPID) approach for the pitch system of a large wind turbine. Nonlinear PID approaches based on hyperbolic secant functions are used for the CPC, ICP and ATDC, respectively. As simulation platform, the 5-MW reference turbine developed by NREL and the software FAST are used. Results show that the NPID approach can provide significant improvements in the control performance in comparison to the classic control approach, in particular when the wind speed goes far from its rated value.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"83 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":"130335496","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/CCTA.2018.8511533
Hong Wang, Z. Qu
In this paper, the summary of the stochastic swing equation will be firstly given taking into account of DERs. This will then be followed by the development of stochastic distribution control model that links the power sources and the loads with the PDF of the frequency using Fokker Planck Kolmogorov (FPK) equations. A generic constrained optimization problem will be formulated, where the cost function is composed of a kind of “functional distance” between the actual and the desired PDFs of the frequency. A feasible solution using B-spine Neural Networks based stochastic distribution control model will be described. Using the obtained stochastic distribution control model, a feedback type control algorithm will be described that uses controllable power sources and the loads to shape the PDF of the frequency or to minimize the randomness of the frequency via minimized entropy approach. Future directions will be briefly discussed in the later part of the paper.
{"title":"Narrowing Frequency Probability Density Function for Achieving Minimized Uncertainties in Power Systems Operation – a Stochastic Distribution Control Perspective","authors":"Hong Wang, Z. Qu","doi":"10.1109/CCTA.2018.8511533","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511533","url":null,"abstract":"In this paper, the summary of the stochastic swing equation will be firstly given taking into account of DERs. This will then be followed by the development of stochastic distribution control model that links the power sources and the loads with the PDF of the frequency using Fokker Planck Kolmogorov (FPK) equations. A generic constrained optimization problem will be formulated, where the cost function is composed of a kind of “functional distance” between the actual and the desired PDFs of the frequency. A feasible solution using B-spine Neural Networks based stochastic distribution control model will be described. Using the obtained stochastic distribution control model, a feedback type control algorithm will be described that uses controllable power sources and the loads to shape the PDF of the frequency or to minimize the randomness of the frequency via minimized entropy approach. Future directions will be briefly discussed in the later part of the paper.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"9 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":"117040067","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/CCTA.2018.8511588
K. Chernyshov
An alternative approach to define the anisotropic norm of random vectors is proposed, based on a symmetric Tsallis divergence measure constructed within the present paper. The consideration is motivated by a definition available in the literature, which is based on Kullback-Leibler divergence and, thus, being non-symmetric, what, at least from a theoretical point of view, stimulates to consider some other possibilities in this field.
{"title":"The Anisotropic Norm of Random Vectors: Defining via a Symmetric Tsallis Divergence","authors":"K. Chernyshov","doi":"10.1109/CCTA.2018.8511588","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511588","url":null,"abstract":"An alternative approach to define the anisotropic norm of random vectors is proposed, based on a symmetric Tsallis divergence measure constructed within the present paper. The consideration is motivated by a definition available in the literature, which is based on Kullback-Leibler divergence and, thus, being non-symmetric, what, at least from a theoretical point of view, stimulates to consider some other possibilities in this field.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"1 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":"131233076","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/CCTA.2018.8511508
Frieder Gottmann, H. Wind, O. Sawodny
Autonomous driving at the limits of the vehicle dynamics is a challenging task, which exploits the capabilities of the vehicle. In autonomous racing the superior goal is to reduce the time necessary to drive a lap. Using rear axle steering gives additional actuation to enhance the vehicle's capabilities up to the tire friction limits and to further reduce the laptime. This paper presents a comparison of a production car to a car with an additional rear axle steering on the basis of a racing line optimization and the resulting laptime. The benefits of this additional actuation are outlined, coming from an increasing vehicle dynamics potential and from an adaptive placement on the track. Different models are taken into account during racing line optimization to compare them and discuss their influence on the results. It is shown, that a simplified vehicle dynamics model gives a suitable approximation of the optimal racing line compared to a simple lumped mass model. Furthermore, the rear axle steered car is less sensitive on modeling simplifications in comparison to the standard car.
{"title":"On the Influence of Rear Axle Steering and Modeling Depth on a Model Based Racing Line Generation for Autonomous Racing","authors":"Frieder Gottmann, H. Wind, O. Sawodny","doi":"10.1109/CCTA.2018.8511508","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511508","url":null,"abstract":"Autonomous driving at the limits of the vehicle dynamics is a challenging task, which exploits the capabilities of the vehicle. In autonomous racing the superior goal is to reduce the time necessary to drive a lap. Using rear axle steering gives additional actuation to enhance the vehicle's capabilities up to the tire friction limits and to further reduce the laptime. This paper presents a comparison of a production car to a car with an additional rear axle steering on the basis of a racing line optimization and the resulting laptime. The benefits of this additional actuation are outlined, coming from an increasing vehicle dynamics potential and from an adaptive placement on the track. Different models are taken into account during racing line optimization to compare them and discuss their influence on the results. It is shown, that a simplified vehicle dynamics model gives a suitable approximation of the optimal racing line compared to a simple lumped mass model. Furthermore, the rear axle steered car is less sensitive on modeling simplifications in comparison to the standard car.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"36 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":"128410598","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/ccta.2018.8511581
{"title":"CCTA 2018 Organization","authors":"","doi":"10.1109/ccta.2018.8511581","DOIUrl":"https://doi.org/10.1109/ccta.2018.8511581","url":null,"abstract":"","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"34 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":"132119169","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/CCTA.2018.8511361
Isao Kimoto, K. Takaba
This paper deals with the fast SLAM algorithm for the line-based SLAM problem with a laser range scanner for a single two-wheeled mobile robot. Since the computational time of the estimation process per each step depends on the number of observed landmarks, and we control the computational time by adaptively tuning the number of particles according to the number of the observed landmarks. First, we review the estimation process of the fast line-based SLAM algorithm. Then, we propose a method for the prediction of the computational time and how to control it by using the number of particles. Finally, we show simulation results of the proposed method in order to verify its effectiveness.
{"title":"Effective Line-Based SLAM with Adaptive Tuning of Particles","authors":"Isao Kimoto, K. Takaba","doi":"10.1109/CCTA.2018.8511361","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511361","url":null,"abstract":"This paper deals with the fast SLAM algorithm for the line-based SLAM problem with a laser range scanner for a single two-wheeled mobile robot. Since the computational time of the estimation process per each step depends on the number of observed landmarks, and we control the computational time by adaptively tuning the number of particles according to the number of the observed landmarks. First, we review the estimation process of the fast line-based SLAM algorithm. Then, we propose a method for the prediction of the computational time and how to control it by using the number of particles. Finally, we show simulation results of the proposed method in order to verify its effectiveness.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"105 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":"133910007","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/CCTA.2018.8511523
Maryam Abdollahi
In this paper, the problem of simultaneous sensor and actuator fault detection, isolation and estimation (FDIE) for nonlinear Euler-Lagrange (EL) systems is addressed. First, an output redefinition and a state coordinate transformation are employed that do not use any a priori knowledge about the system nonlinearities to decouple the system into two subsystems where each subsystem is only affected by either a sensor or an actuator fault. Then, two separate sliding mode observers (SMO) are employed to estimate sensor and actuator faults corresponding to these subsystems. Simulation results are provided for an Autonomous Underwater Vehicle (AUV) that is modeled by EL equations. The results demonstrate the capabilities and benefits as well as the performance of our proposed FDIE approach as compared to the existing results in the literature.
{"title":"Simultaneous Sensor and Actuator Fault Detection, Isolation and Estimation of Nonlinear Euler-Lagrange Systems Using Sliding Mode Observers","authors":"Maryam Abdollahi","doi":"10.1109/CCTA.2018.8511523","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511523","url":null,"abstract":"In this paper, the problem of simultaneous sensor and actuator fault detection, isolation and estimation (FDIE) for nonlinear Euler-Lagrange (EL) systems is addressed. First, an output redefinition and a state coordinate transformation are employed that do not use any a priori knowledge about the system nonlinearities to decouple the system into two subsystems where each subsystem is only affected by either a sensor or an actuator fault. Then, two separate sliding mode observers (SMO) are employed to estimate sensor and actuator faults corresponding to these subsystems. Simulation results are provided for an Autonomous Underwater Vehicle (AUV) that is modeled by EL equations. The results demonstrate the capabilities and benefits as well as the performance of our proposed FDIE approach as compared to the existing results in the literature.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"24 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":"121181107","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/CCTA.2018.8511605
T. Kigezi, J. Dunne
Reconstruction of engine in-cylinder pressure with observers in conventional engines has extensively been studied in the literature. The subject however remains unaddressed for Free-piston Engines (FPEs). An in-cylinder pressure observer suitable for FPEs is developed in this paper. The observer reconstructs in-cylinder pressure from measured piston position and net heat release rate. Observer development starts by examining the commonly adopted high gain observer for nonlinear systems, showing its limitations in a numerical FPE case study. A newly developed sliding mode observer that overcomes these limitations is then proposed. The proposed observer has a finite-time converging error, making it suitable for applications requiring accurate and real-time pressure estimation. Effectiveness of the observer is analytically proven and verified by simulation. The proposed observer is finally generalized into a large family of sliding mode observers.
{"title":"Development of an In-Cylinder Pressure Observer for Free-Piston Engines","authors":"T. Kigezi, J. Dunne","doi":"10.1109/CCTA.2018.8511605","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511605","url":null,"abstract":"Reconstruction of engine in-cylinder pressure with observers in conventional engines has extensively been studied in the literature. The subject however remains unaddressed for Free-piston Engines (FPEs). An in-cylinder pressure observer suitable for FPEs is developed in this paper. The observer reconstructs in-cylinder pressure from measured piston position and net heat release rate. Observer development starts by examining the commonly adopted high gain observer for nonlinear systems, showing its limitations in a numerical FPE case study. A newly developed sliding mode observer that overcomes these limitations is then proposed. The proposed observer has a finite-time converging error, making it suitable for applications requiring accurate and real-time pressure estimation. Effectiveness of the observer is analytically proven and verified by simulation. The proposed observer is finally generalized into a large family of sliding mode observers.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"71 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":"121378233","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/CCTA.2018.8511450
A. Pajares, E. Schuster
Tokamaks are toroidal devices in which a plasma is confined by means of helical magnetic fields with the purpose of obtaining energy from nuclear fusion reactions. The safety factor, $q$, measures the pitch of the helical magnetic field lines in a tokamak. Active control of the $q$ profile (i.e., spatial shape) is needed due to its relationship with plasma performance, steady-state operation, and magneto-hydrodynamic stability. However, the responses of some plasma magnitudes, such as the electron temperature, are difficult to model and introduce a high level of uncertainty in the model used for $q$-profile control design. Control algorithms that are robust against such model uncertainties must be developed in order to ensure successful q-profile regulation. In this work, a nonlinear, robust $q$-profile controller is designed using feedback linearization and nonlinear damping techniques. The controller makes use of plasma current modulation, neutral beam injection, electron-cyclotron heating & current drive, and electron density modulation as actuation methods. A simulation study is carried out for a DIII-D scenario to test the controller's performance under the presence of electron temperature uncertainties.
{"title":"Nonlinear Robust Safety Factor Profile Control in Tokamaks via Feedback Linearization and Nonlinear Damping Techniques","authors":"A. Pajares, E. Schuster","doi":"10.1109/CCTA.2018.8511450","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511450","url":null,"abstract":"Tokamaks are toroidal devices in which a plasma is confined by means of helical magnetic fields with the purpose of obtaining energy from nuclear fusion reactions. The safety factor, $q$, measures the pitch of the helical magnetic field lines in a tokamak. Active control of the $q$ profile (i.e., spatial shape) is needed due to its relationship with plasma performance, steady-state operation, and magneto-hydrodynamic stability. However, the responses of some plasma magnitudes, such as the electron temperature, are difficult to model and introduce a high level of uncertainty in the model used for $q$-profile control design. Control algorithms that are robust against such model uncertainties must be developed in order to ensure successful q-profile regulation. In this work, a nonlinear, robust $q$-profile controller is designed using feedback linearization and nonlinear damping techniques. The controller makes use of plasma current modulation, neutral beam injection, electron-cyclotron heating & current drive, and electron density modulation as actuation methods. A simulation study is carried out for a DIII-D scenario to test the controller's performance under the presence of electron temperature uncertainties.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"65 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":"128685263","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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