Pub Date : 2018-08-01DOI: 10.1109/CCTA.2018.8511481
Kumiko Tadano, Y. Maeno, Takehiro Itou, Hisaya Wakayama, Masatsugu Ogawa
We propose a dynamic rebalancing control algorithm for the swarm of transfer vehicles to improve the throughput of an unreliable production facility. The facility has unpredictable frequent changes in production capacity, where the optimal transfer task schedule of the swarm for a particular set of transfer requests may become obsolete within a short time period. Thus the proposed algorithm does not search for the optimal schedule but adapts the transfer behaviors of the swarm to arbitrary changes in production by rebalancing the stock levels. Through numerical experiments, we find that the throughput achieved by the proposed algorithm is 15% larger than that by the conventional manufacturing industry practice, and the necessary buffer capacity for the proposed algorithm is about 50% smaller than that for the conventional practice.
{"title":"Robust Transfer Vehicle Swarm for Unreliable Production Facility","authors":"Kumiko Tadano, Y. Maeno, Takehiro Itou, Hisaya Wakayama, Masatsugu Ogawa","doi":"10.1109/CCTA.2018.8511481","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511481","url":null,"abstract":"We propose a dynamic rebalancing control algorithm for the swarm of transfer vehicles to improve the throughput of an unreliable production facility. The facility has unpredictable frequent changes in production capacity, where the optimal transfer task schedule of the swarm for a particular set of transfer requests may become obsolete within a short time period. Thus the proposed algorithm does not search for the optimal schedule but adapts the transfer behaviors of the swarm to arbitrary changes in production by rebalancing the stock levels. Through numerical experiments, we find that the throughput achieved by the proposed algorithm is 15% larger than that by the conventional manufacturing industry practice, and the necessary buffer capacity for the proposed algorithm is about 50% smaller than that for the conventional practice.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"15 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":"121400701","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.2018.8511571
B. Meier, M. Oettmeier, J. Fiedler, T. Bertram
In this paper the power consumption model of a circulating wet runner pump is presented. Such a model provides several advantages since it can be used for example to detect issues during operation of the pump. For instance, dry running which might damage the bearings of the pump can be detected based on deviations between the measured power and the power predicted by the model. Furthermore, based on the power model the volume flow which passes the pump can be determined without a volume flow sensor and thus save costs. As the overall power consumption of the pump is influenced by different components such as electrical and friction losses, models of the individual components which have an influence on the power consumption are presented. Then, the components are combined to one overall power consumption model and the model parameters are identified by measurements. Finally, the model is validated by comparison of the dynamic behaviour of the model with the actual measured power consumption.
{"title":"Power Consumption Model of a Circulating Wet Runner Pump","authors":"B. Meier, M. Oettmeier, J. Fiedler, T. Bertram","doi":"10.1109/CCTA.2018.8511571","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511571","url":null,"abstract":"In this paper the power consumption model of a circulating wet runner pump is presented. Such a model provides several advantages since it can be used for example to detect issues during operation of the pump. For instance, dry running which might damage the bearings of the pump can be detected based on deviations between the measured power and the power predicted by the model. Furthermore, based on the power model the volume flow which passes the pump can be determined without a volume flow sensor and thus save costs. As the overall power consumption of the pump is influenced by different components such as electrical and friction losses, models of the individual components which have an influence on the power consumption are presented. Then, the components are combined to one overall power consumption model and the model parameters are identified by measurements. Finally, the model is validated by comparison of the dynamic behaviour of the model with the actual measured power consumption.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"45 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":"113970298","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.2018.8511556
S. Caba, M. Lepper, Steven Liu
In this paper the nonlinear dynamics of a pressure boosting system consisting of multiple parallel centrifugal pumps, a pressure accumulator and a connected load are modeled. The modeling focus is on detailed component descriptions and their dynamical coupling, mainly introduced by the parallel connected pumps. Based on the model, a controller based on Input-Output Linearization is designed to decouple the outputs. Furthermore, an Extended Kalman Filter including the hydraulic dynamics is implemented to overcome the necessity of flow and pressure measurements. Therefore, the combined control scheme only interacts with the variable-speed drive. The functionality of the proposed control algorithm is proved by a test bench implementation.
{"title":"Nonlinear Controller and Estimator Design for Multi-Pump Systems","authors":"S. Caba, M. Lepper, Steven Liu","doi":"10.1109/CCTA.2018.8511556","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511556","url":null,"abstract":"In this paper the nonlinear dynamics of a pressure boosting system consisting of multiple parallel centrifugal pumps, a pressure accumulator and a connected load are modeled. The modeling focus is on detailed component descriptions and their dynamical coupling, mainly introduced by the parallel connected pumps. Based on the model, a controller based on Input-Output Linearization is designed to decouple the outputs. Furthermore, an Extended Kalman Filter including the hydraulic dynamics is implemented to overcome the necessity of flow and pressure measurements. Therefore, the combined control scheme only interacts with the variable-speed drive. The functionality of the proposed control algorithm is proved by a test bench implementation.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"83 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113981301","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.2018.8511416
Georgios Lyrnpcropoulos, M. Borrello, Nikoletta Margari
Valve flow control has always attracted research due to the wide breadth of applications it offers. Its use in advanced applications, such as air and oxygen flow control for neonatal ventilation has demanded higher specifications for accuracy and performance. In this paper, we propose a model reference adaptive control scheme for valve flow control of ventilators which utilizes multiple models that correspond to different operating points of the valve. Switching between models operates according to level of flow using a smoothing mechanism. In addition, a inverse hysteresis model is used to attenuate the hysteresis effect. The scheme has been implemented and tested on multiple valves and using several accuracy and stress tests, providing excellent results.
{"title":"Multiple Model Adaptive Control of Valve Flow Using Event-Triggered Switching","authors":"Georgios Lyrnpcropoulos, M. Borrello, Nikoletta Margari","doi":"10.1109/CCTA.2018.8511416","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511416","url":null,"abstract":"Valve flow control has always attracted research due to the wide breadth of applications it offers. Its use in advanced applications, such as air and oxygen flow control for neonatal ventilation has demanded higher specifications for accuracy and performance. In this paper, we propose a model reference adaptive control scheme for valve flow control of ventilators which utilizes multiple models that correspond to different operating points of the valve. Switching between models operates according to level of flow using a smoothing mechanism. In addition, a inverse hysteresis model is used to attenuate the hysteresis effect. The scheme has been implemented and tested on multiple valves and using several accuracy and stress tests, providing excellent results.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"97 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":"124522214","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.2018.8511425
Klemens Kranawetter, Richard Seeber, P. Mayr, G. Pirker, R. Bauer, M. Horn
This paper presents an approach for developing transient strategies for multi-cylinder gas engines using only a single cylinder in a hardware-in-the-loop setup. Engine components that are physically not present are replaced by a real-time model. The model generates pressure and speed trajectories, which are applied to the single-cylinder engine to ensure that its behavior is identical to its operation as part of the multicylinder engine. Design and analysis of two of the controllers used for that purpose are discussed. For the control of the charge air pressure, a concept based on nonlinear decoupling and a strategy maximizing the actuator range available for disturbance rejection is presented. To control the fuel gas pressure, a linear plant model is obtained and a controller motivated by stability conditions is proposed.
{"title":"Charge Air and Fuel Gas Pressure Control on a HiL-System for the Development of Transient Large Bore Gas Engines","authors":"Klemens Kranawetter, Richard Seeber, P. Mayr, G. Pirker, R. Bauer, M. Horn","doi":"10.1109/CCTA.2018.8511425","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511425","url":null,"abstract":"This paper presents an approach for developing transient strategies for multi-cylinder gas engines using only a single cylinder in a hardware-in-the-loop setup. Engine components that are physically not present are replaced by a real-time model. The model generates pressure and speed trajectories, which are applied to the single-cylinder engine to ensure that its behavior is identical to its operation as part of the multicylinder engine. Design and analysis of two of the controllers used for that purpose are discussed. For the control of the charge air pressure, a concept based on nonlinear decoupling and a strategy maximizing the actuator range available for disturbance rejection is presented. To control the fuel gas pressure, a linear plant model is obtained and a controller motivated by stability conditions is proposed.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"86 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":"127724083","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.2018.8511479
Byoung-Ju Jeon, Min-guk Seo, Hyo-Sang Shin, A. Tsourdos
In this paper, theoretical analysis on the incremental backstepping control is suggested especially under the existence of model uncertainties. This algorithm is proposed in the previous studies by modifying the backstepping method to reduce model dependency. Because this method is a type of nonlinear control and the model uncertainties are assumed to be considered, it is difficult to have theoretical analysis, which causes lack of understandings about this algorithm. Therefore, this paper suggests closed-loop analysis with simplified dynamics under the model uncertainty. Transfer function is derived and poles, stability condition, steady state error, and settling time are presented. In addition, the effects of model uncertainties and gains are identified through analysis. Proposed analysis is meaningful in terms of establishing critical understandings about the algorithm, even though the simplified dynamics is applied for analysis purpose.
{"title":"Understandings of the Incremental Backstepping Control Through Theoretical Analysis Under the Model Uncertainties","authors":"Byoung-Ju Jeon, Min-guk Seo, Hyo-Sang Shin, A. Tsourdos","doi":"10.1109/CCTA.2018.8511479","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511479","url":null,"abstract":"In this paper, theoretical analysis on the incremental backstepping control is suggested especially under the existence of model uncertainties. This algorithm is proposed in the previous studies by modifying the backstepping method to reduce model dependency. Because this method is a type of nonlinear control and the model uncertainties are assumed to be considered, it is difficult to have theoretical analysis, which causes lack of understandings about this algorithm. Therefore, this paper suggests closed-loop analysis with simplified dynamics under the model uncertainty. Transfer function is derived and poles, stability condition, steady state error, and settling time are presented. In addition, the effects of model uncertainties and gains are identified through analysis. Proposed analysis is meaningful in terms of establishing critical understandings about the algorithm, even though the simplified dynamics is applied for analysis purpose.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"8 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":"126533178","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.2018.8511386
Rasmus L. Christensen, Kresten K. Sørensen, R. Wisniewski, M. Sznaier
Refrigeration containers are being used like never before. The growing desire for exotic goods in much of the western world, puts an ever growing strain on the refrigeration systems that are used for transport. During one trip, a refrigeration container might experience temperatures ranging from −25 to 40 degrees celcius, whilst being tossed around on the deck of the freighter. This work, develops a method to detect errors aboard these refrigeration containers, that can be used to lower the maintenance costs. Furthermore, a prediction of the “time-to-failure” is presented, which enables the refrigeration container owners to decide whether or not a refrigeration container can endure a trip.
{"title":"Unsupervised Fault Detection of Reefer Containers: A Moments-Based SDP Approach","authors":"Rasmus L. Christensen, Kresten K. Sørensen, R. Wisniewski, M. Sznaier","doi":"10.1109/CCTA.2018.8511386","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511386","url":null,"abstract":"Refrigeration containers are being used like never before. The growing desire for exotic goods in much of the western world, puts an ever growing strain on the refrigeration systems that are used for transport. During one trip, a refrigeration container might experience temperatures ranging from −25 to 40 degrees celcius, whilst being tossed around on the deck of the freighter. This work, develops a method to detect errors aboard these refrigeration containers, that can be used to lower the maintenance costs. Furthermore, a prediction of the “time-to-failure” is presented, which enables the refrigeration container owners to decide whether or not a refrigeration container can endure a trip.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"16 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":"128114052","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.2018.8511354
S. Albrektsen, T. Bryne, T. Johansen
Positioning using global navigation satellite systems (GNSS) has for several years been the de facto method for long-range navigation of ground, marine and aerial vehicles. With global coverage, high accuracy, and lightweight receivers, GNSS positioning has several desirable properties, especially on unmanned aerial systems (UAVs) with limited sensor payload capacity. However, due to the low signal-to-noise ratio (SNR) of the GNSS signals the navigation signal is prone to malicious attacks, such as jammig or spoofing. In the last few years, alternative solutions for absolute positioning of unmanned vehicles have emerged. One example of this is positioning using a phased array radio systems (PARS). PARS equipment has the potential to provide position measurements that are accurate within tens of meters. The PARS solutions typically have significantly higher SNR and strongly encrypted messages, which makes them robust towards malicious attacks. This paper presents a method for an inertial navigation system which is aided using redundant position sensors. The high-accuracy RTK solution is the primary position reference, when it is available. The PARS is used to detect if GNSS solution is being spoofed (or jammed), and is used as the fall-back positioning solution.
{"title":"Robust and Secure UAV Navigation Using GNSS, Phased-Array Radio System and Inertial Sensor Fusion","authors":"S. Albrektsen, T. Bryne, T. Johansen","doi":"10.1109/CCTA.2018.8511354","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511354","url":null,"abstract":"Positioning using global navigation satellite systems (GNSS) has for several years been the de facto method for long-range navigation of ground, marine and aerial vehicles. With global coverage, high accuracy, and lightweight receivers, GNSS positioning has several desirable properties, especially on unmanned aerial systems (UAVs) with limited sensor payload capacity. However, due to the low signal-to-noise ratio (SNR) of the GNSS signals the navigation signal is prone to malicious attacks, such as jammig or spoofing. In the last few years, alternative solutions for absolute positioning of unmanned vehicles have emerged. One example of this is positioning using a phased array radio systems (PARS). PARS equipment has the potential to provide position measurements that are accurate within tens of meters. The PARS solutions typically have significantly higher SNR and strongly encrypted messages, which makes them robust towards malicious attacks. This paper presents a method for an inertial navigation system which is aided using redundant position sensors. The high-accuracy RTK solution is the primary position reference, when it is available. The PARS is used to detect if GNSS solution is being spoofed (or jammed), and is used as the fall-back positioning solution.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"54 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113937120","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.2018.8511357
Hyejin Han, R. Sanfelice
This paper presents a hybrid control approach for grasping objects by multiple agents without rebounding. When multiple agents grasp an object cooperatively, the motion of the agents is constrained due to the geometrical and frictional conditions at the contact points. In this paper, each agent acting on an object of interest is controlled by a hybrid controller which includes a position controller, a force controller, and some logic to coordinate grasping. The proposed approach provides a method to steer the agents to grasping positions on an object along appropriate directions and to asymptotically exert stabilizing forces at each contact point. The stability properties induced by the hybrid controller can be asserted using Lyapunov stability tools for hybrid systems. The set of allowed initial conditions guaranteed is characterized using sublevel sets of Lyapunov functions. The proposed algorithm is verified in simulations.
{"title":"A Hybrid Control Algorithm for Object Grasping Using Multiple Agents","authors":"Hyejin Han, R. Sanfelice","doi":"10.1109/CCTA.2018.8511357","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511357","url":null,"abstract":"This paper presents a hybrid control approach for grasping objects by multiple agents without rebounding. When multiple agents grasp an object cooperatively, the motion of the agents is constrained due to the geometrical and frictional conditions at the contact points. In this paper, each agent acting on an object of interest is controlled by a hybrid controller which includes a position controller, a force controller, and some logic to coordinate grasping. The proposed approach provides a method to steer the agents to grasping positions on an object along appropriate directions and to asymptotically exert stabilizing forces at each contact point. The stability properties induced by the hybrid controller can be asserted using Lyapunov stability tools for hybrid systems. The set of allowed initial conditions guaranteed is characterized using sublevel sets of Lyapunov functions. The proposed algorithm is verified in simulations.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"218 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":"131645827","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.2018.8511379
Brad Thompson
The stability of an existing non-linear system model of a Dubins vehicle is investigated. The discovery of the system state variables and their dynamics from simulation data is attempted, using machine learning (ML) techniques. The results show that there is at least one case in which system state-space discovery through a ML approach is unsuccessful. Technology which relies upon state abstraction from inferential learning techniques may be vulnerable to failure if the cases are not well understood.
{"title":"System State Variable Discovery Counter Example","authors":"Brad Thompson","doi":"10.1109/CCTA.2018.8511379","DOIUrl":"https://doi.org/10.1109/CCTA.2018.8511379","url":null,"abstract":"The stability of an existing non-linear system model of a Dubins vehicle is investigated. The discovery of the system state variables and their dynamics from simulation data is attempted, using machine learning (ML) techniques. The results show that there is at least one case in which system state-space discovery through a ML approach is unsuccessful. Technology which relies upon state abstraction from inferential learning techniques may be vulnerable to failure if the cases are not well understood.","PeriodicalId":358360,"journal":{"name":"2018 IEEE Conference on Control Technology and Applications (CCTA)","volume":"63 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":"131757095","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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