Pub Date : 2011-06-20DOI: 10.1109/MED.2011.5983028
Tomislav Lugaric, D. Nad, Z. Vukic
Underwater exploration is experiencing an ever increasing usage of both autonomous and remotely operated robotic vehicles. Vehicles are typically equipped with several sensors depending on the mission type being carried out. Integration of all these systems together, as well as obtaining data from them presents a significant challenge. This article describes a software architecture which represents all entities in the system as equivalent modules, while hiding their specifics from the user. Each module in the system is fully defined only by the data it produces and the commands it accepts. Modules are coupled together using a communication interface which again hides the underlying protocol from the user, and is based solely on message exchange. This architecture allows quick reconfiguration of the vehicle, easy integration of various sensor systems and provides the application developers with a higher level of abstraction.
{"title":"A modular approach to system integration in underwater robotics","authors":"Tomislav Lugaric, D. Nad, Z. Vukic","doi":"10.1109/MED.2011.5983028","DOIUrl":"https://doi.org/10.1109/MED.2011.5983028","url":null,"abstract":"Underwater exploration is experiencing an ever increasing usage of both autonomous and remotely operated robotic vehicles. Vehicles are typically equipped with several sensors depending on the mission type being carried out. Integration of all these systems together, as well as obtaining data from them presents a significant challenge. This article describes a software architecture which represents all entities in the system as equivalent modules, while hiding their specifics from the user. Each module in the system is fully defined only by the data it produces and the commands it accepts. Modules are coupled together using a communication interface which again hides the underlying protocol from the user, and is based solely on message exchange. This architecture allows quick reconfiguration of the vehicle, easy integration of various sensor systems and provides the application developers with a higher level of abstraction.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127066702","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 : 2011-06-20DOI: 10.1109/MED.2011.5983207
F. Cheli, M. Pezzola, N. Taroni, P. Mazzoleni, E. Zappa
The aim of this work is to investigate how the driver's movements influence the behavior of the motorcycle. In the past, many interesting researches about this topic were made to examine the coupled effects in the lateral dynamics of the global mechanical system, but only in a numerical approach, most of all through multibody models. In this paper, the interaction between motorcycle and rider is analyzed in an experimental way, using a sport motorbike. A non - contact vision - based measurement system was developed to identify the position of the driver, using a camera and a target fixed to the pilot's back. Two kinds of tests were executed: the first examines the differences in vehicle's performance when the driver moves his upper-body or not, the second one inspects the effects of the driving style of different riders. Both steady state and transient manoeuvres were performed to achieve these goals. During the analysis, the physical quantities concerning the system's dynamic are summarized by means of synthesis indices deriving from bibliography or developed specifically for this work.
{"title":"Driver's movements influence on the lateral dynamic of a sport motorbike","authors":"F. Cheli, M. Pezzola, N. Taroni, P. Mazzoleni, E. Zappa","doi":"10.1109/MED.2011.5983207","DOIUrl":"https://doi.org/10.1109/MED.2011.5983207","url":null,"abstract":"The aim of this work is to investigate how the driver's movements influence the behavior of the motorcycle. In the past, many interesting researches about this topic were made to examine the coupled effects in the lateral dynamics of the global mechanical system, but only in a numerical approach, most of all through multibody models. In this paper, the interaction between motorcycle and rider is analyzed in an experimental way, using a sport motorbike. A non - contact vision - based measurement system was developed to identify the position of the driver, using a camera and a target fixed to the pilot's back. Two kinds of tests were executed: the first examines the differences in vehicle's performance when the driver moves his upper-body or not, the second one inspects the effects of the driving style of different riders. Both steady state and transient manoeuvres were performed to achieve these goals. During the analysis, the physical quantities concerning the system's dynamic are summarized by means of synthesis indices deriving from bibliography or developed specifically for this work.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125841173","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 : 2011-06-20DOI: 10.1109/MED.2011.5983158
M. Caccia, M. Bibuli, G. Bruzzone, V. Djapic, S. Fioravanti, A. Grati
This article describes the collaborative effort between NURC and CNR-ISSIA to increase the functional autonomy of Unmanned Surface Vehicles. The assets used for this demonstration were the CNR-ISSIA Charlie catamaran-type USV with its autonomy software, and NURC's payload module consisting of a sonar, pan-tilt unit, and the control software for both. The goal was to interface the two separate autonomy modules in order to maneuver the USV relative to an interesting target (demonstrated with a bottom target). Charlie's mission is to carry the payload while performing various behaviors to survey an area of interest. Whenever an interesting potential target is seen in the view of the forward looking sonar, the payload control software takes over control from Charlie's main vehicle computer, interrupts its pre-programmed behavior, and sends the necessary messages so the USV adapts its track based on the target location. The demonstration took place in Murter, Croatia during the 2010 Breaking the Surface Symposium.
{"title":"Modular USV and payload design for advanced capabilities in marine security applications","authors":"M. Caccia, M. Bibuli, G. Bruzzone, V. Djapic, S. Fioravanti, A. Grati","doi":"10.1109/MED.2011.5983158","DOIUrl":"https://doi.org/10.1109/MED.2011.5983158","url":null,"abstract":"This article describes the collaborative effort between NURC and CNR-ISSIA to increase the functional autonomy of Unmanned Surface Vehicles. The assets used for this demonstration were the CNR-ISSIA Charlie catamaran-type USV with its autonomy software, and NURC's payload module consisting of a sonar, pan-tilt unit, and the control software for both. The goal was to interface the two separate autonomy modules in order to maneuver the USV relative to an interesting target (demonstrated with a bottom target). Charlie's mission is to carry the payload while performing various behaviors to survey an area of interest. Whenever an interesting potential target is seen in the view of the forward looking sonar, the payload control software takes over control from Charlie's main vehicle computer, interrupts its pre-programmed behavior, and sends the necessary messages so the USV adapts its track based on the target location. The demonstration took place in Murter, Croatia during the 2010 Breaking the Surface Symposium.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126864125","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 : 2011-06-20DOI: 10.1109/MED.2011.5983164
Po Wu, P. Antsaklis
In this paper, the passivity indices for both linear and nonlinear multi-agent systems with feedforward and feedback interconnections are derived. For linear systems, the passivity indices are explicitly characterized, while the passivity indices in the nonlinear case are characterized by a set of matrix inequalities. We also focus on symmetric interconnections and specialize the passivity indices results to this case. An illustrative example is also given.
{"title":"Passivity indices for symmetrically interconnected distributed systems","authors":"Po Wu, P. Antsaklis","doi":"10.1109/MED.2011.5983164","DOIUrl":"https://doi.org/10.1109/MED.2011.5983164","url":null,"abstract":"In this paper, the passivity indices for both linear and nonlinear multi-agent systems with feedforward and feedback interconnections are derived. For linear systems, the passivity indices are explicitly characterized, while the passivity indices in the nonlinear case are characterized by a set of matrix inequalities. We also focus on symmetric interconnections and specialize the passivity indices results to this case. An illustrative example is also given.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126469445","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 : 2011-06-20DOI: 10.1109/MED.2011.5983123
H. H. Nejad, D. Sauter, S. Aberkane, C. Aubrun
This paper deals with the problem of fault detection and isolation (FDI) of a networked control system (NCS). In this configuration a linear time invariant(LTI) system communicates with controller/FDI over a shared medium. The medium supports a limited number of simultaneous connections between sensors and FDI system. Furthermore, it is assumed that there is the random and unknown packet dropouts in the controller-to-actuator link. Objective is to find a strategy for residual signals generating which network effects are taken into account. In addition, by means of these residuals fault detection and isolation of system is possible. A set of structured residual based on parity relation approach is proposed. It guarantees robustness to system disturbances and packet dropout while each residual is designed to be sensitive to some sensor faults. The efficiency of the proposed approach will be illustrated with a simulation example.
{"title":"Fault detection and isolation in networked control systems with access constraints and packet dropouts","authors":"H. H. Nejad, D. Sauter, S. Aberkane, C. Aubrun","doi":"10.1109/MED.2011.5983123","DOIUrl":"https://doi.org/10.1109/MED.2011.5983123","url":null,"abstract":"This paper deals with the problem of fault detection and isolation (FDI) of a networked control system (NCS). In this configuration a linear time invariant(LTI) system communicates with controller/FDI over a shared medium. The medium supports a limited number of simultaneous connections between sensors and FDI system. Furthermore, it is assumed that there is the random and unknown packet dropouts in the controller-to-actuator link. Objective is to find a strategy for residual signals generating which network effects are taken into account. In addition, by means of these residuals fault detection and isolation of system is possible. A set of structured residual based on parity relation approach is proposed. It guarantees robustness to system disturbances and packet dropout while each residual is designed to be sensitive to some sensor faults. The efficiency of the proposed approach will be illustrated with a simulation example.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124371313","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 : 2011-06-20DOI: 10.1109/MED.2011.5983006
E. Kamal, A. Aitouche, M. Bayart
This paper presents the novel Fuzzy Fault Tolerant Control (FFTC) of Wind Energy Conversion System (WECS) subject to actuator faults. The proposed algorithm combines the merits of: (i) The states of the closed-loop system will follow those of a user-defined stable reference model despite the presence of actuator faults; (ii) Maximizes the power coefficient for a fixed pitch variable speed wind turbines. The Takagi-Sugeno (TS) fuzzy model system with actuator faults is adopted for modelling the nonlinear dynamics of the WECS and establishing fuzzy state observer. Sufficient conditions are derived for robust stabilization in the sense of Lyapunov asymptotic stability and are formulated in the format of Linear Matrix Inequalities (LMIs). The design technique is applied to a dynamic model of wind energy conversion system to illustrate the effectiveness of the proposed FFTC.
{"title":"A fuzzy approach for actuator fault-tolerant control of Wind Energy Conversion Systems","authors":"E. Kamal, A. Aitouche, M. Bayart","doi":"10.1109/MED.2011.5983006","DOIUrl":"https://doi.org/10.1109/MED.2011.5983006","url":null,"abstract":"This paper presents the novel Fuzzy Fault Tolerant Control (FFTC) of Wind Energy Conversion System (WECS) subject to actuator faults. The proposed algorithm combines the merits of: (i) The states of the closed-loop system will follow those of a user-defined stable reference model despite the presence of actuator faults; (ii) Maximizes the power coefficient for a fixed pitch variable speed wind turbines. The Takagi-Sugeno (TS) fuzzy model system with actuator faults is adopted for modelling the nonlinear dynamics of the WECS and establishing fuzzy state observer. Sufficient conditions are derived for robust stabilization in the sense of Lyapunov asymptotic stability and are formulated in the format of Linear Matrix Inequalities (LMIs). The design technique is applied to a dynamic model of wind energy conversion system to illustrate the effectiveness of the proposed FFTC.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127882057","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 : 2011-06-20DOI: 10.1109/MED.2011.5983217
R. Zivanovic
To formulate estimation problem for a observed nonlinear system, differential equations are required as a system model. We recast those equations as integral equations and apply integral operator, which is approximated by Chebyshev interpolating polynomial. Resulting equations of the nonlinear estimation problem are integral equations discretized on the grid of Chebyshev points. A sequence of linear least squares problems are solved iteratively. Grid resolution can be determined automatically to maximize computation accuracy. Numerical efficiency is achieved by applying iterative method that requires only matrix-vector multiplications, and via implementation of Discrete Cosine Transform when solving indefinite integrals. The estimation algorithm works with matrices having bounded low condition number compared to large and unbounded condition number for the formulation with differential operator. This achievement has important practical value when applying the algorithm with high-order models when the differential operator formulation is typically ill-conditioned. Application to a Duffing system having chaotic response, has been used to illustrate advantages of the proposed estimation algorithm based on Chebyshev integral operator.
{"title":"State and parameter estimation using Chebyshev integral operator","authors":"R. Zivanovic","doi":"10.1109/MED.2011.5983217","DOIUrl":"https://doi.org/10.1109/MED.2011.5983217","url":null,"abstract":"To formulate estimation problem for a observed nonlinear system, differential equations are required as a system model. We recast those equations as integral equations and apply integral operator, which is approximated by Chebyshev interpolating polynomial. Resulting equations of the nonlinear estimation problem are integral equations discretized on the grid of Chebyshev points. A sequence of linear least squares problems are solved iteratively. Grid resolution can be determined automatically to maximize computation accuracy. Numerical efficiency is achieved by applying iterative method that requires only matrix-vector multiplications, and via implementation of Discrete Cosine Transform when solving indefinite integrals. The estimation algorithm works with matrices having bounded low condition number compared to large and unbounded condition number for the formulation with differential operator. This achievement has important practical value when applying the algorithm with high-order models when the differential operator formulation is typically ill-conditioned. Application to a Duffing system having chaotic response, has been used to illustrate advantages of the proposed estimation algorithm based on Chebyshev integral operator.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127461319","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 : 2011-06-20DOI: 10.1109/MED.2011.5983225
Petros Giataganas, N. Evangeliou, Y. Koveos, Eleni Kelasidi, A. Tzes
The development and experimental evaluation of a prototype endoscopic robotic surgical tool is presented in this article. Smart memory alloys (SMA) are used as wires in a tendon-driven actuation mechanism. The 2N-DOF redundant manipulator is a cascade configuration of N-universal joint modules. The kinematics of the tool is analyzed and simple yet effective controllers relying on a constrained non-linear optimization problem are offered. The surgical tool's shape can be deformed according to a predefined profile leading to more versatile configurations than the existing designs. The efficiency of the overall system is investigated in experimental studies where its performance is evaluated by a customized 3D-video system.
{"title":"Design and experimental evaluation of an innovative SMA-based tendon-driven redundant endoscopic robotic surgical tool","authors":"Petros Giataganas, N. Evangeliou, Y. Koveos, Eleni Kelasidi, A. Tzes","doi":"10.1109/MED.2011.5983225","DOIUrl":"https://doi.org/10.1109/MED.2011.5983225","url":null,"abstract":"The development and experimental evaluation of a prototype endoscopic robotic surgical tool is presented in this article. Smart memory alloys (SMA) are used as wires in a tendon-driven actuation mechanism. The 2N-DOF redundant manipulator is a cascade configuration of N-universal joint modules. The kinematics of the tool is analyzed and simple yet effective controllers relying on a constrained non-linear optimization problem are offered. The surgical tool's shape can be deformed according to a predefined profile leading to more versatile configurations than the existing designs. The efficiency of the overall system is investigated in experimental studies where its performance is evaluated by a customized 3D-video system.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132845205","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 : 2011-06-20DOI: 10.1109/MED.2011.5983132
Y. Stergiopoulos, A. Tzes
The article examines the distributed optimization problem in mobile heterogeneous sensor networks. Most coordination algorithms are designed based on geometric characteristics of the corresponding Voronoi cells of the nodes. However, these works consider networks where the sensing patterns of the nodes are identical. This article considers coordination of heterogeneous networks, where the sensing radii of the nodes differ, while the proposed deployment algorithm for area-coverage optimization is based on a modified Voronoi-like space partitioning scheme. The proposed control scheme is developed in a distributed manner, while the advantages of the proposed technique are validated via simulation studies.
{"title":"Coverage-oriented coordination of mobile heterogeneous networks","authors":"Y. Stergiopoulos, A. Tzes","doi":"10.1109/MED.2011.5983132","DOIUrl":"https://doi.org/10.1109/MED.2011.5983132","url":null,"abstract":"The article examines the distributed optimization problem in mobile heterogeneous sensor networks. Most coordination algorithms are designed based on geometric characteristics of the corresponding Voronoi cells of the nodes. However, these works consider networks where the sensing patterns of the nodes are identical. This article considers coordination of heterogeneous networks, where the sensing radii of the nodes differ, while the proposed deployment algorithm for area-coverage optimization is based on a modified Voronoi-like space partitioning scheme. The proposed control scheme is developed in a distributed manner, while the advantages of the proposed technique are validated via simulation studies.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133563187","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 : 2011-06-20DOI: 10.1109/MED.2011.5983179
F. Altaf, José Araújo, Aitor Hernandez, H. Sandberg, K. Johansson
This paper studies the design and real-time implementation of an event-triggered controller for a nonlinear 3D tower crane where the communication between the controller and the actuators is performed over a low-power wireless network. A flexible Event-Generation Circuit (EGC) is proposed in order to implement event-driven controllers for Networked Control Systems. Furthermore, a detailed experimental analysis on the performance of the event-triggered controller and the influence of packet losses on the transmitted actuation messages are presented. The results show that the event-triggered controllers in networked control systems are able to maintain the same level of performance as compared to periodic controllers, while increasing the sensors/actuators lifetime by reducing network bandwidth utilization.
{"title":"Wireless event-triggered controller for a 3D tower crane lab process","authors":"F. Altaf, José Araújo, Aitor Hernandez, H. Sandberg, K. Johansson","doi":"10.1109/MED.2011.5983179","DOIUrl":"https://doi.org/10.1109/MED.2011.5983179","url":null,"abstract":"This paper studies the design and real-time implementation of an event-triggered controller for a nonlinear 3D tower crane where the communication between the controller and the actuators is performed over a low-power wireless network. A flexible Event-Generation Circuit (EGC) is proposed in order to implement event-driven controllers for Networked Control Systems. Furthermore, a detailed experimental analysis on the performance of the event-triggered controller and the influence of packet losses on the transmitted actuation messages are presented. The results show that the event-triggered controllers in networked control systems are able to maintain the same level of performance as compared to periodic controllers, while increasing the sensors/actuators lifetime by reducing network bandwidth utilization.","PeriodicalId":146203,"journal":{"name":"2011 19th Mediterranean Conference on Control & Automation (MED)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2011-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127021939","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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