Pub Date : 2004-12-01DOI: 10.1109/RAMECH.2004.1438938
H. Lau, Alex K. S. Ng
Artificial immune system (AIS) has recently been actively researched with a number of emerging engineering applications that has capitalized from its characteristics including self-organization, distributive control, knowledge mapping and fault tolerance. This paper reports the development of an AIS paradigm for the distributive control of a multi-jointed, redundant manipulator. Traditionally, manipulator control is achieved by analytical solutions. By adopting a multi-agent-based control paradigm, a multi-jointed manipulator can be thought of as a group of separately controlled agents. In this paper, we investigate the viability of a multi-agent immunology-based control framework for the trajectory control of a multi-jointed redundant manipulator.
{"title":"Immunology-based control framework for multi-jointed redundant manipulators","authors":"H. Lau, Alex K. S. Ng","doi":"10.1109/RAMECH.2004.1438938","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438938","url":null,"abstract":"Artificial immune system (AIS) has recently been actively researched with a number of emerging engineering applications that has capitalized from its characteristics including self-organization, distributive control, knowledge mapping and fault tolerance. This paper reports the development of an AIS paradigm for the distributive control of a multi-jointed, redundant manipulator. Traditionally, manipulator control is achieved by analytical solutions. By adopting a multi-agent-based control paradigm, a multi-jointed manipulator can be thought of as a group of separately controlled agents. In this paper, we investigate the viability of a multi-agent immunology-based control framework for the trajectory control of a multi-jointed redundant manipulator.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125338664","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438076
Wang Xing-cheng, Liang Aiguo
The design of a fuzzy variable structure controller for an inverted pendulum is considered in this paper. The method is based on fuzzy sets and variable structure control. Simulation results show that the fuzzy variable structure controller is robust to uncertain factors and external disturbance.
{"title":"Fuzzy variable structure control for an inverted pendulum","authors":"Wang Xing-cheng, Liang Aiguo","doi":"10.1109/RAMECH.2004.1438076","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438076","url":null,"abstract":"The design of a fuzzy variable structure controller for an inverted pendulum is considered in this paper. The method is based on fuzzy sets and variable structure control. Simulation results show that the fuzzy variable structure controller is robust to uncertain factors and external disturbance.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122972059","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438009
A.M. Idghamishi, S. Hashtrudi Zad
A framework for online passive fault diagnosis in hierarchical finite-state machines (HFSM) is presented and applied to an ozone generation plant. This approach takes advantage of system structure to reduce computational complexity. Here, the system model is broken into simpler substructures called D-holons. A diagnoser is constructed for each D-holon. At any given time, only a subset of the diagnosers are active, and as a result, instead of the entire model of the system, only the models of D-holons associated with active diagnosers are used for diagnosis. Furthermore, a set of sufficient conditions is provided under which the diagnosis process becomes semi-modular. The ozone generation plant under study, consisting of two units, is modeled as an HFSM. It is shown that a proper choice of sensors results in modular diagnosis (one diagnoser for each unit). Following the proposed framework, a hierarchical fault diagnosis system is designed for the plant. It is shown that the proposed approach significantly reduces the complexity of constructing and storing the diagnosis system.
{"title":"Hierarchical fault diagnosis: application to an ozone plant","authors":"A.M. Idghamishi, S. Hashtrudi Zad","doi":"10.1109/RAMECH.2004.1438009","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438009","url":null,"abstract":"A framework for online passive fault diagnosis in hierarchical finite-state machines (HFSM) is presented and applied to an ozone generation plant. This approach takes advantage of system structure to reduce computational complexity. Here, the system model is broken into simpler substructures called D-holons. A diagnoser is constructed for each D-holon. At any given time, only a subset of the diagnosers are active, and as a result, instead of the entire model of the system, only the models of D-holons associated with active diagnosers are used for diagnosis. Furthermore, a set of sufficient conditions is provided under which the diagnosis process becomes semi-modular. The ozone generation plant under study, consisting of two units, is modeled as an HFSM. It is shown that a proper choice of sensors results in modular diagnosis (one diagnoser for each unit). Following the proposed framework, a hierarchical fault diagnosis system is designed for the plant. It is shown that the proposed approach significantly reduces the complexity of constructing and storing the diagnosis system.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114146501","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438923
P. Huynh
The paper aims to describe kinematic hybrid position/force control for a three-degree-of-freedom (3-DOF) in-parallel actuated manipulator, and its application to peg-in-hole task about 10 /spl mu/m clearance. The control system consists of a low-level position servo driven by force feedback in base coordinates. The computation required for the control is only inverse kinematics, which is very simple for the parallel-link manipulator. Assisted by a human operator, the motion is generated by using force-torque based joystick commands and/or preplanned motion data. In teleoperation mode, the human operator can intervene and superpose corrective motions over the preplanned searching motion.
{"title":"Kinematic hybrid position/force control of a 3-DOF in-parallel actuated manipulator","authors":"P. Huynh","doi":"10.1109/RAMECH.2004.1438923","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438923","url":null,"abstract":"The paper aims to describe kinematic hybrid position/force control for a three-degree-of-freedom (3-DOF) in-parallel actuated manipulator, and its application to peg-in-hole task about 10 /spl mu/m clearance. The control system consists of a low-level position servo driven by force feedback in base coordinates. The computation required for the control is only inverse kinematics, which is very simple for the parallel-link manipulator. Assisted by a human operator, the motion is generated by using force-torque based joystick commands and/or preplanned motion data. In teleoperation mode, the human operator can intervene and superpose corrective motions over the preplanned searching motion.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116844761","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438963
A. Sehgal, J. Kadarusman, Leslie D. Fife
TOUCH is a real-time computer vision system that has been developed in order to aid the operation of autonomous underwater vehicles (AUVs) and remotely operated vehicles (ROVs). The algorithm is based on a modified 4-connectivity approach that scans the incoming frames for a target hue range and based upon the largest connected blobs of hue, tracks an object and provides the two dimensional Cartesian coordinates of the desired object. Since few algorithms exist for tracking and recognizing objects in underwater environments, this algorithm provides a way for AUVs and ROVs to acquire, track or recognize objects by using a relatively fast and inexpensive vision system. This paper presents the details on TOUCH, its testing, some areas that warrant improvement and possible course of action for the future.
{"title":"TOUCH: a robotic vision system for underwater object tracking","authors":"A. Sehgal, J. Kadarusman, Leslie D. Fife","doi":"10.1109/RAMECH.2004.1438963","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438963","url":null,"abstract":"TOUCH is a real-time computer vision system that has been developed in order to aid the operation of autonomous underwater vehicles (AUVs) and remotely operated vehicles (ROVs). The algorithm is based on a modified 4-connectivity approach that scans the incoming frames for a target hue range and based upon the largest connected blobs of hue, tracks an object and provides the two dimensional Cartesian coordinates of the desired object. Since few algorithms exist for tracking and recognizing objects in underwater environments, this algorithm provides a way for AUVs and ROVs to acquire, track or recognize objects by using a relatively fast and inexpensive vision system. This paper presents the details on TOUCH, its testing, some areas that warrant improvement and possible course of action for the future.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129829626","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438000
J. Weingarten, R. Groff, D. Koditschek
This paper introduces a framework for representing, generating, and then tuning gaits of legged robots. We introduce a convenient parametrization of gait generators as dynamical systems possessing designer specified stable limit cycles over an appropriate torus. This parametrization affords a continuous selection of operation within a coordination design plane, inspired by biology, spanned by axes that determine the mix of "feedforward/feedback" and "centralized/decentralized" control. Tuning the gait generator parameters through repeated physical experiments with our robot hexapod, RHex, determines the appropriate operating point - the mix of feedback and degree of control decentralization - to achieve significantly increased performance relative to the centralized feedforward operating point that has governed its previous behavior. The present preliminary experiments with these new gaits suggest that they may permit for the first time locomotion over extremely rough terrain that is almost as reliable, rapid, and energy efficient as the very fastest or most efficient outcomes centralized feedforward gaits can achieve on level ground.
{"title":"A framework for the coordination of legged robot gaits","authors":"J. Weingarten, R. Groff, D. Koditschek","doi":"10.1109/RAMECH.2004.1438000","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438000","url":null,"abstract":"This paper introduces a framework for representing, generating, and then tuning gaits of legged robots. We introduce a convenient parametrization of gait generators as dynamical systems possessing designer specified stable limit cycles over an appropriate torus. This parametrization affords a continuous selection of operation within a coordination design plane, inspired by biology, spanned by axes that determine the mix of \"feedforward/feedback\" and \"centralized/decentralized\" control. Tuning the gait generator parameters through repeated physical experiments with our robot hexapod, RHex, determines the appropriate operating point - the mix of feedback and degree of control decentralization - to achieve significantly increased performance relative to the centralized feedforward operating point that has governed its previous behavior. The present preliminary experiments with these new gaits suggest that they may permit for the first time locomotion over extremely rough terrain that is almost as reliable, rapid, and energy efficient as the very fastest or most efficient outcomes centralized feedforward gaits can achieve on level ground.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129849999","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438890
K. Yan, W. Ng, K. Ling, Tien-I Liu, Yan Yu, W. O'Dell
Precise needle placement is important for a number of percutaneous interventions. However insertions into soft tissues can be difficult to learn and to perform, due to tissue deformation, needle deflection and limited visual feedback. Complications associated with poor placement have been studied. Yet to date, little quantitative information is known about the interaction between needles and soft tissues during penetration, and few effective physically based needle guidance systems exist for such procedures. In this paper, some important works dealing with needle guidance in soft tissue were first reviewed. Then a "smart needling" system was proposed and some preliminary work was described.
{"title":"Literature review on needle guidance in soft and preliminary work on smart needling","authors":"K. Yan, W. Ng, K. Ling, Tien-I Liu, Yan Yu, W. O'Dell","doi":"10.1109/RAMECH.2004.1438890","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438890","url":null,"abstract":"Precise needle placement is important for a number of percutaneous interventions. However insertions into soft tissues can be difficult to learn and to perform, due to tissue deformation, needle deflection and limited visual feedback. Complications associated with poor placement have been studied. Yet to date, little quantitative information is known about the interaction between needles and soft tissues during penetration, and few effective physically based needle guidance systems exist for such procedures. In this paper, some important works dealing with needle guidance in soft tissue were first reviewed. Then a \"smart needling\" system was proposed and some preliminary work was described.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128341941","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438894
Q. Meng, Mark H. Lee
The worldwide population of elderly people is rapidly growing and is set to become a major problem in the coming decades. This phenomenon has the potential to create a huge market for domestic service robots that can assist with the care and support of the elderly. Robots that are able to help the user with specific physical tasks are likely to become very important in the future, but so far, unlike industrial robots, assistive robots are still under-developed and are not widely used. We analyse the nature of the requirements for assistive robotics for the elderly and argue that traditional "industrial" robot design and control approaches are inappropriate to tackle the key problem areas of safety, adaptivity, long-term autonomy of operation, user-friendliness and low costs. We present a novel approach to the control of autonomous assistive robots for the home, with emphasis on the special requirements for in situ learning, including software compensation for low precision hardware components. Our system consists of a modified behaviour-based architecture with integrated knowledge representation and planning abilities. Automatic error-recovery is implemented as an activation spreading mechanism and is distributed across the behaviour repertoire. Context-based experience is learned during both error recovery and normal action and assimilated into the behaviours. This allows reuse across different tasks, and facilitates gradual but life-long improvements in system performance. To evaluate our approach, an experimental laboratory testbed was constructed using low-cost, low-precision components. Our system was implemented in software and a series of experiments were performed in order to investigate a range of tasks. The tasks were selected to face some of the key issues identified and the results show the potential for software solutions to overcome the barriers to successful assistive robotics for the elderly. The methods, experiments and results are described in this paper.
{"title":"Learning and control in assistive robotics for the elderly","authors":"Q. Meng, Mark H. Lee","doi":"10.1109/RAMECH.2004.1438894","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438894","url":null,"abstract":"The worldwide population of elderly people is rapidly growing and is set to become a major problem in the coming decades. This phenomenon has the potential to create a huge market for domestic service robots that can assist with the care and support of the elderly. Robots that are able to help the user with specific physical tasks are likely to become very important in the future, but so far, unlike industrial robots, assistive robots are still under-developed and are not widely used. We analyse the nature of the requirements for assistive robotics for the elderly and argue that traditional \"industrial\" robot design and control approaches are inappropriate to tackle the key problem areas of safety, adaptivity, long-term autonomy of operation, user-friendliness and low costs. We present a novel approach to the control of autonomous assistive robots for the home, with emphasis on the special requirements for in situ learning, including software compensation for low precision hardware components. Our system consists of a modified behaviour-based architecture with integrated knowledge representation and planning abilities. Automatic error-recovery is implemented as an activation spreading mechanism and is distributed across the behaviour repertoire. Context-based experience is learned during both error recovery and normal action and assimilated into the behaviours. This allows reuse across different tasks, and facilitates gradual but life-long improvements in system performance. To evaluate our approach, an experimental laboratory testbed was constructed using low-cost, low-precision components. Our system was implemented in software and a series of experiments were performed in order to investigate a range of tasks. The tasks were selected to face some of the key issues identified and the results show the potential for software solutions to overcome the barriers to successful assistive robotics for the elderly. The methods, experiments and results are described in this paper.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129089359","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438967
M. Hoque, M. Takasaki, Y. Ishino, T. Mizuno
This paper presents an active suspension technique for a three-degrees-of-freedom (3-DOF) vibration isolation system using negative stiffness. A mode-based digital controller is designed based on a theoretical model to generate negative stiffness by active suspension. The active suspension mechanism, in conjunction with a conventional spring in series, can generate infinite stiffness against direct disturbances on the isolation table. Three-axis motions of the isolation table in the vertical directions are actively controlled by the proposed system. Experimental results show that the active suspension system using the proposed controller well evaluates and describes the zero-compliance against direct disturbances.
{"title":"Design of a mode-based controller for 3-DOF vibration isolation system","authors":"M. Hoque, M. Takasaki, Y. Ishino, T. Mizuno","doi":"10.1109/RAMECH.2004.1438967","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438967","url":null,"abstract":"This paper presents an active suspension technique for a three-degrees-of-freedom (3-DOF) vibration isolation system using negative stiffness. A mode-based digital controller is designed based on a theoretical model to generate negative stiffness by active suspension. The active suspension mechanism, in conjunction with a conventional spring in series, can generate infinite stiffness against direct disturbances on the isolation table. Three-axis motions of the isolation table in the vertical directions are actively controlled by the proposed system. Experimental results show that the active suspension system using the proposed controller well evaluates and describes the zero-compliance against direct disturbances.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127740845","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 : 2004-12-01DOI: 10.1109/RAMECH.2004.1438033
G. Fang, G. Dissanayake, H. Lau
To efficiently explore an unknown environment with a team of robots, a coordinated strategy that maximises the exploration area is required. This is a difficult optimisation problem, as there may exist many suboptimal solutions. In order to reduce the search space to a region that is near the optimal, a behaviour-based exploration strategy is used to define the region in which an optimal solution can be found. A numerical optimisation technique is then used to find the solution in this region. In particular, the proposed strategy uses a potential-fields technique to obtain a coarse movement direction for each robot. A nonlinear optimisation method is then used to calculate the velocity and angle deviation from the coarse direction to achieve the maximum exploration for each move. Simulation results have shown that the proposed method provides an efficient exploration strategy.
{"title":"A behaviour-based optimisation strategy for multi-robot exploration","authors":"G. Fang, G. Dissanayake, H. Lau","doi":"10.1109/RAMECH.2004.1438033","DOIUrl":"https://doi.org/10.1109/RAMECH.2004.1438033","url":null,"abstract":"To efficiently explore an unknown environment with a team of robots, a coordinated strategy that maximises the exploration area is required. This is a difficult optimisation problem, as there may exist many suboptimal solutions. In order to reduce the search space to a region that is near the optimal, a behaviour-based exploration strategy is used to define the region in which an optimal solution can be found. A numerical optimisation technique is then used to find the solution in this region. In particular, the proposed strategy uses a potential-fields technique to obtain a coarse movement direction for each robot. A nonlinear optimisation method is then used to calculate the velocity and angle deviation from the coarse direction to achieve the maximum exploration for each move. Simulation results have shown that the proposed method provides an efficient exploration strategy.","PeriodicalId":252964,"journal":{"name":"IEEE Conference on Robotics, Automation and Mechatronics, 2004.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126272501","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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