Pub Date : 2017-08-01DOI: 10.1109/MMAR.2017.8046939
J. Wegehaupt, Dariusz Buchczik, O. Krauze
The process of loose materials grinding is directly dependent on the type of feed and its physical parameters resulting from presence of water in the material. The grinding process in the electromagnetic mill installation is carried out on dry material, using pneumatic transport and classification system with recycle. Preliminary analyses have shown the possibility to significantly improve the product quality and efficiency of the milling process by appropriate control of the moisture content of the milled material. The main objective of the research is to develop a model describing the changes of moisture content of bulk material in the installation of the electromagnetic mill. This paper presents the results of preliminary studies on models describing the drying process in the path of material classification and its separation from the transport air.
{"title":"Preliminary studies on modelling the drying process in product classification and separation path in an electromagnetic mill installation","authors":"J. Wegehaupt, Dariusz Buchczik, O. Krauze","doi":"10.1109/MMAR.2017.8046939","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046939","url":null,"abstract":"The process of loose materials grinding is directly dependent on the type of feed and its physical parameters resulting from presence of water in the material. The grinding process in the electromagnetic mill installation is carried out on dry material, using pneumatic transport and classification system with recycle. Preliminary analyses have shown the possibility to significantly improve the product quality and efficiency of the milling process by appropriate control of the moisture content of the milled material. The main objective of the research is to develop a model describing the changes of moisture content of bulk material in the installation of the electromagnetic mill. This paper presents the results of preliminary studies on models describing the drying process in the path of material classification and its separation from the transport air.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128984801","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046891
A. Chmielewski, J. Możaryn, Maciej Krzeminski
This article presents a theoretical background for an artificial neural network (ANN) model of the alpha type Stirling engine where thermodynamic dependencies, connected with equations of motion for the piston-crankshaft system with three degrees of freedom were taken into account. Because of the highly nonlinear description of Stirling engine dynamics, the ANN was employed, that modelled output power of Stirling engine as a function of the input power, molar mass, load current, pressure obtained by gas combustion and working parameters of the engine. The ANN model was tested on experimental data, gathered at the laboratory stand, in different working conditions. The proposed ANN model provides good results for both training and testing data-sets.
{"title":"Theoretical and experimental background for artificial neural network modeling of alpha type Stirling engine","authors":"A. Chmielewski, J. Możaryn, Maciej Krzeminski","doi":"10.1109/MMAR.2017.8046891","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046891","url":null,"abstract":"This article presents a theoretical background for an artificial neural network (ANN) model of the alpha type Stirling engine where thermodynamic dependencies, connected with equations of motion for the piston-crankshaft system with three degrees of freedom were taken into account. Because of the highly nonlinear description of Stirling engine dynamics, the ANN was employed, that modelled output power of Stirling engine as a function of the input power, molar mass, load current, pressure obtained by gas combustion and working parameters of the engine. The ANN model was tested on experimental data, gathered at the laboratory stand, in different working conditions. The proposed ANN model provides good results for both training and testing data-sets.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"32 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127836472","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046977
M. Zugaj
A reconfiguration method using model-based control allocation scheme is proposed in this paper. A reconfigurable closed-loop control system is established for control of a UAV (unmanned aerial vehicle) fixed wing aircraft in autonomous flight in case of single and multiple control surfaces failures. The control allocation is determined by using of a nonlinear dynamic model of a UAV aircraft. The model is also used to demonstrate the proposed method. Simulation results show that the damaged aircraft control via proposed reconfiguration method can be carried out and satisfactory controllability performance may be achieved.
{"title":"Reconfiguration of fixed-wing UAV control system in autonomous flight","authors":"M. Zugaj","doi":"10.1109/MMAR.2017.8046977","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046977","url":null,"abstract":"A reconfiguration method using model-based control allocation scheme is proposed in this paper. A reconfigurable closed-loop control system is established for control of a UAV (unmanned aerial vehicle) fixed wing aircraft in autonomous flight in case of single and multiple control surfaces failures. The control allocation is determined by using of a nonlinear dynamic model of a UAV aircraft. The model is also used to demonstrate the proposed method. Simulation results show that the damaged aircraft control via proposed reconfiguration method can be carried out and satisfactory controllability performance may be achieved.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124340112","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046847
Benedikt Haus, Paolo Mercorelli, N. Werner
This paper presents a heuristic, signal-based approach to compensate time delay-like effects caused by friction hysteresis in a novel kind of valve actuator. It works by exploiting a-priori knowledge about (and the periodicity of) the desired trajectory, under the premise that an existing feedforward control already tracks the desired trajectory, apart from the mentioned time delay effect. However, the emphasis of this contribution is put on experimental results obtained with a test stand in order to substantiate the effectiveness of the simplistic compensating technique that was already described in earlier works. The hysteresis loop is modelled and simulated to match the measurements, though no model is needed by the compensation algorithm.
{"title":"Friction hysteresis compensation using phase correction of periodic trajectories","authors":"Benedikt Haus, Paolo Mercorelli, N. Werner","doi":"10.1109/MMAR.2017.8046847","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046847","url":null,"abstract":"This paper presents a heuristic, signal-based approach to compensate time delay-like effects caused by friction hysteresis in a novel kind of valve actuator. It works by exploiting a-priori knowledge about (and the periodicity of) the desired trajectory, under the premise that an existing feedforward control already tracks the desired trajectory, apart from the mentioned time delay effect. However, the emphasis of this contribution is put on experimental results obtained with a test stand in order to substantiate the effectiveness of the simplistic compensating technique that was already described in earlier works. The hysteresis loop is modelled and simulated to match the measurements, though no model is needed by the compensation algorithm.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121065013","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046903
Chase Haddix, A. Bahrani, A. Kawala-Janik, W. Besio, Guoqiang Yu, S. Sunderam
To better characterize movement-related neurophysiological change, the authors propose to measure not only neural activity through the electroencephalogram (EEG) but also cerebral blood flow (CBF) using a new technology, near-infrared diffuse correlation spectroscopy (DCS). A preliminary trial is described, in which EEG, DCS, and exerted force were simultaneously recorded during a cue-triggered hand grip task. Eight channels of EEG were acquired from frontal, central, and occipital regions, and DCS signals were collected from locations over frontal and motor cortex. Event-related desynchronization (ERD) was observed at the onset of hand movement and lasted until movement ceased. EEG from the motor area showed a significant ERD in the 8–13 Hz mu band (p<0.001). Mean CBF increased during the task by 6.8 % (p<0.001) in the motor location and by 4.5 % (p<0.001) in the frontal location, respectively. These preliminary observations suggest that a combination of electrical and optical measurements may provide a more complete characterization of brain dynamics related to movement. A broader study is required to explore the potential benefit of these combined measurements when used as command signals for brain-computer interfaces.
{"title":"Trial measurement of movement-related cortical dynamics using electroencephalography and diffuse correlation spectroscopy","authors":"Chase Haddix, A. Bahrani, A. Kawala-Janik, W. Besio, Guoqiang Yu, S. Sunderam","doi":"10.1109/MMAR.2017.8046903","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046903","url":null,"abstract":"To better characterize movement-related neurophysiological change, the authors propose to measure not only neural activity through the electroencephalogram (EEG) but also cerebral blood flow (CBF) using a new technology, near-infrared diffuse correlation spectroscopy (DCS). A preliminary trial is described, in which EEG, DCS, and exerted force were simultaneously recorded during a cue-triggered hand grip task. Eight channels of EEG were acquired from frontal, central, and occipital regions, and DCS signals were collected from locations over frontal and motor cortex. Event-related desynchronization (ERD) was observed at the onset of hand movement and lasted until movement ceased. EEG from the motor area showed a significant ERD in the 8–13 Hz mu band (p<0.001). Mean CBF increased during the task by 6.8 % (p<0.001) in the motor location and by 4.5 % (p<0.001) in the frontal location, respectively. These preliminary observations suggest that a combination of electrical and optical measurements may provide a more complete characterization of brain dynamics related to movement. A broader study is required to explore the potential benefit of these combined measurements when used as command signals for brain-computer interfaces.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117164895","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046955
M. Pazera, M. Witczak, Mariusz Buciakowski, M. Mrugalski
The paper is devoted to the problem of a Takagi-Sugeno(TS)-based robust simultaneous actuator and sensor faults estimator design for the purpose of the Fault Diagnosis (FD) of non-linear systems. The proposed methodology of designing a TS-based H∞ fault estimator is developed in this paper. The main novelty of the approach is associated with possibly of simultaneous sensor and actuator faults estimation. The developed approach guaranties a predefined disturbance attenuation level and convergence of the designed estimator. The illustrative part of the paper shows an example of the application of the developed approach in the task of the fault diagnosis of the multi-tank system.
{"title":"Simultaneous estimation of multiple actuator anc sensor faults for Takagi-Sugeno fuzzy systems","authors":"M. Pazera, M. Witczak, Mariusz Buciakowski, M. Mrugalski","doi":"10.1109/MMAR.2017.8046955","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046955","url":null,"abstract":"The paper is devoted to the problem of a Takagi-Sugeno(TS)-based robust simultaneous actuator and sensor faults estimator design for the purpose of the Fault Diagnosis (FD) of non-linear systems. The proposed methodology of designing a TS-based H∞ fault estimator is developed in this paper. The main novelty of the approach is associated with possibly of simultaneous sensor and actuator faults estimation. The developed approach guaranties a predefined disturbance attenuation level and convergence of the designed estimator. The illustrative part of the paper shows an example of the application of the developed approach in the task of the fault diagnosis of the multi-tank system.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117288976","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046869
A. Kowalewski
Extremal problems for parabolic systems with time-varying lags are presented. An optimal boundary control problem for distributed parabolic systems with boundary conditions involving time-varying lags is solved. The time horizon is fixed. Making use of Dubovicki-Milutin scheme, necessary and sufficient conditions of optimality for the Neumann problem with the quadratic performance functionals and constrained control are derived.
{"title":"Extremal problems for distributed parabolic systems with boundary conditions involving time-varying lags","authors":"A. Kowalewski","doi":"10.1109/MMAR.2017.8046869","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046869","url":null,"abstract":"Extremal problems for parabolic systems with time-varying lags are presented. An optimal boundary control problem for distributed parabolic systems with boundary conditions involving time-varying lags is solved. The time horizon is fixed. Making use of Dubovicki-Milutin scheme, necessary and sufficient conditions of optimality for the Neumann problem with the quadratic performance functionals and constrained control are derived.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"30 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120913789","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046896
I. Golovin, S. Palis
In this article control-based reduction of gantry crane elastic swinging in the trolley travel direction is concerned. As acceleration forces of the trolley are often the reason of these vibrations, they can be utilized in an appropriate damping strategy. For an elastic crane a dynamic model is derived applying the finite element method (FEM). This approach results in a high order state-space model, which should be reduced for the controller design procedure. In order to design a controller, which can be applied for simultaneous damping of elastic vibrations of crane construction and payload sway with varying rope length a robust control approach has been applied.
{"title":"Control-based damping of elastic gantry crane vibrations","authors":"I. Golovin, S. Palis","doi":"10.1109/MMAR.2017.8046896","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046896","url":null,"abstract":"In this article control-based reduction of gantry crane elastic swinging in the trolley travel direction is concerned. As acceleration forces of the trolley are often the reason of these vibrations, they can be utilized in an appropriate damping strategy. For an elastic crane a dynamic model is derived applying the finite element method (FEM). This approach results in a high order state-space model, which should be reduced for the controller design procedure. In order to design a controller, which can be applied for simultaneous damping of elastic vibrations of crane construction and payload sway with varying rope length a robust control approach has been applied.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126885285","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046962
M. Niedzwiedz, Piotr Laszczyk, Piotr Skupin, M. Metzger
In this paper a hybrid chemical reactor, known also as the partially simulated reactor, is presented. Such reactor consists of a jacketed vessel and LabVIEW based real-time simulator of a chemical reaction. The reactor can be used for testing advanced control strategies. Experimenting with the hybrid reactor excludes risk of a thermal runaway because the simulated chemical reaction can be stopped at any time. To make the hybrid reactor a highly nonlinear benchmark plant, the reaction parameters must be properly selected, taking into account all the constraints of the designed system. For this reason, preliminary tests using a numerical simulator were performed to avoid time consuming experiments with the hybrid reactor. In our research, we consider three different models of the batch hybrid reactor. Results show that an overall heat transfer coefficient cannot be assumed constant to obtain a good agreement between the simulation and the measurement data. Moreover, the overall heat transfer coefficient varies with flow through the jacket and a dispersion of its values is different for each model.
{"title":"Hybrid batch reactor modeling and experimental evaluation of heat transfer process","authors":"M. Niedzwiedz, Piotr Laszczyk, Piotr Skupin, M. Metzger","doi":"10.1109/MMAR.2017.8046962","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046962","url":null,"abstract":"In this paper a hybrid chemical reactor, known also as the partially simulated reactor, is presented. Such reactor consists of a jacketed vessel and LabVIEW based real-time simulator of a chemical reaction. The reactor can be used for testing advanced control strategies. Experimenting with the hybrid reactor excludes risk of a thermal runaway because the simulated chemical reaction can be stopped at any time. To make the hybrid reactor a highly nonlinear benchmark plant, the reaction parameters must be properly selected, taking into account all the constraints of the designed system. For this reason, preliminary tests using a numerical simulator were performed to avoid time consuming experiments with the hybrid reactor. In our research, we consider three different models of the batch hybrid reactor. Results show that an overall heat transfer coefficient cannot be assumed constant to obtain a good agreement between the simulation and the measurement data. Moreover, the overall heat transfer coefficient varies with flow through the jacket and a dispersion of its values is different for each model.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126895255","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 : 2017-08-01DOI: 10.1109/MMAR.2017.8046794
Wojciech Giernacki, Mateusz Skwierczynski, Wojciech Witwicki, P. Wroński, P. Kozierski
In this paper a Crazyflie 2.0 nano quadrotor helicopter (quadcopter) as an open source experimental platform for research and education in robotics and control engineering has been presented. This low cost, easily expandable and upgradeable flying robot is here characterized in terms of hardware and software. Three aspects, which demonstrate the potential of broad use of this unmanned aerial vehicle (UAV) by researchers and students, are discussed in the paper. The first one is an acquisition of measurement data from test flights by the proposed, freely available “black-box” software. The second is the use of a new, advanced 4FLY Simulator in order to utilize the MATLAB®/Simulink environment to easily implement a mathematical model of Crazyflie 2.0 dynamics, as well as for a synthesis of various types of controllers with support of OpenGL cross-language in the visualization of simulations results. The 4FLYSimulator allows to test autonomous flights (and landings) with obstacles avoidance and to conduct learning and teaching the basics of Crazyflie 2.0 piloting. In the third aspect the authors outlined promising, preliminary results obtained in control of flying robot by pointing device (positioner) and with the support of a vision system, which basis only on a single Kinect sensor.
{"title":"Crazyflie 2.0 quadrotor as a platform for research and education in robotics and control engineering","authors":"Wojciech Giernacki, Mateusz Skwierczynski, Wojciech Witwicki, P. Wroński, P. Kozierski","doi":"10.1109/MMAR.2017.8046794","DOIUrl":"https://doi.org/10.1109/MMAR.2017.8046794","url":null,"abstract":"In this paper a Crazyflie 2.0 nano quadrotor helicopter (quadcopter) as an open source experimental platform for research and education in robotics and control engineering has been presented. This low cost, easily expandable and upgradeable flying robot is here characterized in terms of hardware and software. Three aspects, which demonstrate the potential of broad use of this unmanned aerial vehicle (UAV) by researchers and students, are discussed in the paper. The first one is an acquisition of measurement data from test flights by the proposed, freely available “black-box” software. The second is the use of a new, advanced 4FLY Simulator in order to utilize the MATLAB®/Simulink environment to easily implement a mathematical model of Crazyflie 2.0 dynamics, as well as for a synthesis of various types of controllers with support of OpenGL cross-language in the visualization of simulations results. The 4FLYSimulator allows to test autonomous flights (and landings) with obstacles avoidance and to conduct learning and teaching the basics of Crazyflie 2.0 piloting. In the third aspect the authors outlined promising, preliminary results obtained in control of flying robot by pointing device (positioner) and with the support of a vision system, which basis only on a single Kinect sensor.","PeriodicalId":189753,"journal":{"name":"2017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126925542","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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