We introduce the notion of repeated failure diagnosability for diagnosing the occurrence of a repeated number of failures in discrete event systems. This generalizes the earlier notion of diagnosability that was used to diagnose the occurrence of a failure, but from which the information regarding the multiplicity of the occurrence of the failure could not be obtained. It is possible that in some systems the same type of failure repeats a multiple number of times. It is desirable to have a diagnoser which not only diagnoses that such a failure has occurred, but also determines the number of times the failure has occurred. To aid such analysis we introduce the notions of K-diagnosability (K failures diagnosability), [1, K]-diagnosability (1 through K failures diagnosability), and [1, /spl infin/]-diagnosability (1 through /spl infin/ failures diagnosability). Here the first (resp., last) notion is the weakest (resp., strongest) of all three and the earlier notion of diagnosability is the same as that of K-diagnosability or that of [1, K]-diagnosability with K=1. We give polynomial algorithms for checking these various notions of repeated failure diagnosability and also present a procedure of polynomial complexity for the online diagnosis of repeated failures.
{"title":"Diagnosis of repeated/intermittent failures in discrete event systems","authors":"Shengbing Jiang, Ratnesh Kumar, H. Garcia","doi":"10.1109/TRA.2003.809590","DOIUrl":"https://doi.org/10.1109/TRA.2003.809590","url":null,"abstract":"We introduce the notion of repeated failure diagnosability for diagnosing the occurrence of a repeated number of failures in discrete event systems. This generalizes the earlier notion of diagnosability that was used to diagnose the occurrence of a failure, but from which the information regarding the multiplicity of the occurrence of the failure could not be obtained. It is possible that in some systems the same type of failure repeats a multiple number of times. It is desirable to have a diagnoser which not only diagnoses that such a failure has occurred, but also determines the number of times the failure has occurred. To aid such analysis we introduce the notions of K-diagnosability (K failures diagnosability), [1, K]-diagnosability (1 through K failures diagnosability), and [1, /spl infin/]-diagnosability (1 through /spl infin/ failures diagnosability). Here the first (resp., last) notion is the weakest (resp., strongest) of all three and the earlier notion of diagnosability is the same as that of K-diagnosability or that of [1, K]-diagnosability with K=1. We give polynomial algorithms for checking these various notions of repeated failure diagnosability and also present a procedure of polynomial complexity for the online diagnosis of repeated failures.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132837192","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}
Pressed by market globalization and concomitant competition, more and more manufacturers are relying on their suppliers to provide raw materials and component parts so as to focus on their core competence. As a result, the coordination of activities across a network of suppliers becomes critical to quickly respond to dynamic market conditions. In this paper, a novel framework combining mathematical optimization and the contract net protocol is presented for make-to-order supply network coordination. Interactions among organizations are modeled by a set of interorganizational precedence constraints and the objective is to achieve the organizations' individual and shared goals of fast product delivery and low inventory. These interorganizational constraints are relaxed by using a set of interorganizational prices that represent marginal costs per unit time for the violation of such constraints. The overall problem is thus decomposed into organizational subproblems, where individual organizations schedule their activities based on their internal situations and interorganizational prices. Coordination is achieved through an iterative price-updating process carried out in a distributed and asynchronous manner. With prices dynamically updated and schedules adjusted, this approach coordinates activities to fulfill existing commitments while maintaining agility to take on new orders. Numerical testing results show that interorganizational prices converge and prices may change as new orders arrive to reflect the new pressure on deliveries.
{"title":"Price-based approach for activity coordination in a supply network","authors":"P. Luh, Ming-Chuan Ni, Haoxun Chen, L. Thakur","doi":"10.1109/TRA.2003.809589","DOIUrl":"https://doi.org/10.1109/TRA.2003.809589","url":null,"abstract":"Pressed by market globalization and concomitant competition, more and more manufacturers are relying on their suppliers to provide raw materials and component parts so as to focus on their core competence. As a result, the coordination of activities across a network of suppliers becomes critical to quickly respond to dynamic market conditions. In this paper, a novel framework combining mathematical optimization and the contract net protocol is presented for make-to-order supply network coordination. Interactions among organizations are modeled by a set of interorganizational precedence constraints and the objective is to achieve the organizations' individual and shared goals of fast product delivery and low inventory. These interorganizational constraints are relaxed by using a set of interorganizational prices that represent marginal costs per unit time for the violation of such constraints. The overall problem is thus decomposed into organizational subproblems, where individual organizations schedule their activities based on their internal situations and interorganizational prices. Coordination is achieved through an iterative price-updating process carried out in a distributed and asynchronous manner. With prices dynamically updated and schedules adjusted, this approach coordinates activities to fulfill existing commitments while maintaining agility to take on new orders. Numerical testing results show that interorganizational prices converge and prices may change as new orders arrive to reflect the new pressure on deliveries.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124852347","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}
This paper proposes a human-assisting manipulator teleoperated by electromyographic (EMG) signals and arm motions. The proposed method can realize a new master-slave manipulator system that uses no mechanical master controller. A person whose forearm has been amputated can use this manipulator as a personal assistant for desktop work. The control system consists of a hand and wrist control part and an arm control part. The hand and wrist control part selects an active joint in the manipulator's end-effector and controls it based on EMG pattern discrimination. The arm control part measures the position of the operator's wrist joint or the amputated part using a three-dimensional position sensor, and the joint angles of the manipulator's arm, except for the end-effector part, are controlled according to this position, which, in turn, corresponds to the position of the manipulator's joint. These control parts enable the operator to control the manipulator intuitively. The distinctive feature of our system is to use a novel statistical neural network for EMG pattern discrimination. The system can adapt itself to changes of the EMG patterns according to the differences among individuals, different locations of the electrodes, and time variation caused by fatigue or sweat. Our experiments have shown that the developed system could learn and estimate the operator's intended motions with a high degree of accuracy using the EMG signals, and that the manipulator could be controlled smoothly. We also confirmed that our system could assist the amputee in performing desktop work.
{"title":"A human-assisting manipulator teleoperated by EMG signals and arm motions","authors":"O. Fukuda, T. Tsuji, M. Kaneko, A. Otsuka","doi":"10.1109/TRA.2003.808873","DOIUrl":"https://doi.org/10.1109/TRA.2003.808873","url":null,"abstract":"This paper proposes a human-assisting manipulator teleoperated by electromyographic (EMG) signals and arm motions. The proposed method can realize a new master-slave manipulator system that uses no mechanical master controller. A person whose forearm has been amputated can use this manipulator as a personal assistant for desktop work. The control system consists of a hand and wrist control part and an arm control part. The hand and wrist control part selects an active joint in the manipulator's end-effector and controls it based on EMG pattern discrimination. The arm control part measures the position of the operator's wrist joint or the amputated part using a three-dimensional position sensor, and the joint angles of the manipulator's arm, except for the end-effector part, are controlled according to this position, which, in turn, corresponds to the position of the manipulator's joint. These control parts enable the operator to control the manipulator intuitively. The distinctive feature of our system is to use a novel statistical neural network for EMG pattern discrimination. The system can adapt itself to changes of the EMG patterns according to the differences among individuals, different locations of the electrodes, and time variation caused by fatigue or sweat. Our experiments have shown that the developed system could learn and estimate the operator's intended motions with a high degree of accuracy using the EMG signals, and that the manipulator could be controlled smoothly. We also confirmed that our system could assist the amputee in performing desktop work.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126044164","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}
This paper presents a control law for the tracking of a cyclic reference trajectory by an underactuated biped robot. The robot studied is a five-link planar robot. The degree of underactuation is one during the single support phase. The control law is defined in such a way that only the geometric evolution of the robot is controlled, not the temporal evolution. To achieve this objective, we consider a time-scaling control. For a given reference path, the temporal evolution during the geometric tracking is completely defined and can be analyzed through the study of the dynamic model. A simple analytical condition is deduced that guarantees convergence toward the cyclic reference trajectory. This condition implies temporal convergence after the geometric convergence. This condition is defined on the cyclic reference path. The control law is stable if the angular momentum around the contact point is greater at the end of the single support phase than at the beginning of the single support phase.
{"title":"Time-scaling control for an underactuated biped robot","authors":"C. Chevallereau","doi":"10.1109/TRA.2003.808863","DOIUrl":"https://doi.org/10.1109/TRA.2003.808863","url":null,"abstract":"This paper presents a control law for the tracking of a cyclic reference trajectory by an underactuated biped robot. The robot studied is a five-link planar robot. The degree of underactuation is one during the single support phase. The control law is defined in such a way that only the geometric evolution of the robot is controlled, not the temporal evolution. To achieve this objective, we consider a time-scaling control. For a given reference path, the temporal evolution during the geometric tracking is completely defined and can be analyzed through the study of the dynamic model. A simple analytical condition is deduced that guarantees convergence toward the cyclic reference trajectory. This condition implies temporal convergence after the geometric convergence. This condition is defined on the cyclic reference path. The control law is stable if the angular momentum around the contact point is greater at the end of the single support phase than at the beginning of the single support phase.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116194230","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}
The position/force tracking control of Lagrangian mechanical systems with classical nonholonomic constraints is addressed in this paper. The main feature of this paper is that 1) control strategy is developed at the dynamic level and can deal with model uncertainties in the mechanical systems; 2) the proposed control law ensures the desired trajectory tracking of the configuration state of the closed-loop system; 3) the tracking error of constraint force is bounded with a controllable bound; and 4) a global asymptotic stability result is obtained in the Lyapunov sense. A detailed numerical example is presented to illustrate the developed method.
{"title":"Robust adaptive motion/force tracking control of uncertain nonholonomic mechanical systems","authors":"M. Oya, C. Su, R. Katoh","doi":"10.1109/TRA.2002.807528","DOIUrl":"https://doi.org/10.1109/TRA.2002.807528","url":null,"abstract":"The position/force tracking control of Lagrangian mechanical systems with classical nonholonomic constraints is addressed in this paper. The main feature of this paper is that 1) control strategy is developed at the dynamic level and can deal with model uncertainties in the mechanical systems; 2) the proposed control law ensures the desired trajectory tracking of the configuration state of the closed-loop system; 3) the tracking error of constraint force is bounded with a controllable bound; and 4) a global asymptotic stability result is obtained in the Lyapunov sense. A detailed numerical example is presented to illustrate the developed method.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128639952","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}
In this paper, the expression "production systems" refers to flow shops, job shops, assembly systems, Kanban systems, and, in general, to any discrete event system which transforms raw material and/or components into products and/or components. Such a system is said to be cyclic if it provides the same sequence of products indefinitely. A schedule of a cyclic production system is defined as soon as the starting time of each operation on the related resource is known. It has been shown that, whatever the feasible schedule applied to the cyclic production system, it is always possible to fully utilize the bottleneck resource. In other words, it is always possible to maximize the throughput of such a system. As a consequence, we aim at finding the schedule which permits to maximize the throughput with a work in process as small as possible. We propose a heuristic approach based on Petri nets to find a near-optimal, if not optimal, solution. We also give a sufficient condition for a solution to be optimal.
{"title":"Optimization of cyclic production systems: a heuristic approach","authors":"F. Chauvet, J. Herrmann, J. Proth","doi":"10.1109/TRA.2002.807529","DOIUrl":"https://doi.org/10.1109/TRA.2002.807529","url":null,"abstract":"In this paper, the expression \"production systems\" refers to flow shops, job shops, assembly systems, Kanban systems, and, in general, to any discrete event system which transforms raw material and/or components into products and/or components. Such a system is said to be cyclic if it provides the same sequence of products indefinitely. A schedule of a cyclic production system is defined as soon as the starting time of each operation on the related resource is known. It has been shown that, whatever the feasible schedule applied to the cyclic production system, it is always possible to fully utilize the bottleneck resource. In other words, it is always possible to maximize the throughput of such a system. As a consequence, we aim at finding the schedule which permits to maximize the throughput with a work in process as small as possible. We propose a heuristic approach based on Petri nets to find a near-optimal, if not optimal, solution. We also give a sufficient condition for a solution to be optimal.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116732357","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}
This paper addresses the forbidden state problem of Petri nets (PN) with liveness requirement and uncontrollable transitions. The proposed approach computes a maximally permissive PN controller, whenever such a controller exists. The first step, based on a Ramadge-Wonham-like reasoning (1989), determines the legal and live maximal behavior the controlled PN should have. In the second step, the theory of regions is used to design control places to add to the original model to realize the desired behavior. Furthermore, necessary and sufficient conditions for the existence of control places realizing the maximum permissive control are given. A parameterized manufacturing application of significant state space is used to show the efficiency of the proposed approach.
{"title":"Design of a live and maximally permissive Petri net controller using the theory of regions","authors":"A. Ghaffari, N. Rezg, Xiaolan Xie","doi":"10.1109/TRA.2002.807555","DOIUrl":"https://doi.org/10.1109/TRA.2002.807555","url":null,"abstract":"This paper addresses the forbidden state problem of Petri nets (PN) with liveness requirement and uncontrollable transitions. The proposed approach computes a maximally permissive PN controller, whenever such a controller exists. The first step, based on a Ramadge-Wonham-like reasoning (1989), determines the legal and live maximal behavior the controlled PN should have. In the second step, the theory of regions is used to design control places to add to the original model to realize the desired behavior. Furthermore, necessary and sufficient conditions for the existence of control places realizing the maximum permissive control are given. A parameterized manufacturing application of significant state space is used to show the efficiency of the proposed approach.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126746076","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}
In this paper, we introduce the concept of switching from one supervisory control to another one when changes in the state of an embedded sensory network occur. The sensory devices are assumed to be single functional, that is, they are programmed to observe and report only one event. The switching model is built based on the two criteria of language observability and state synchronization. Switching model is the basis for a megacontroller, which monitors the state of the sensory network embedded in the plant as well as the state of the supervisor in charge. Every time the state of this network changes, the megacontroller reconfigures the control system by finding an appropriate supervisor.
{"title":"A control switching theory for supervisory control of discrete event systems","authors":"H. Darabi, M. Jafari, A. Buczak","doi":"10.1109/TRA.2002.807551","DOIUrl":"https://doi.org/10.1109/TRA.2002.807551","url":null,"abstract":"In this paper, we introduce the concept of switching from one supervisory control to another one when changes in the state of an embedded sensory network occur. The sensory devices are assumed to be single functional, that is, they are programmed to observe and report only one event. The switching model is built based on the two criteria of language observability and state synchronization. Switching model is the basis for a megacontroller, which monitors the state of the sensory network embedded in the plant as well as the state of the supervisor in charge. Every time the state of this network changes, the megacontroller reconfigures the control system by finding an appropriate supervisor.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129871276","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}
This paper presents a product family representation model which was developed during a research project called CISAL, the purpose of which was to propose an integrated approach for the design of product families and their assembly system. This model is able to deal with partial information from the design of the product family, a situation that often occurs at early stages of the concurrent design of products and production means. The proposed model is assembly-oriented, because the project covered design for assembly, assembly planning, and line layout issues. In fact, it was developed on the basis of the design methodology itself. An originality of the design approach-which impacted the proposed model-is to decompose the product into so-called functional entities defined by the designer. The product family is then seen as an assembly of functional entities that can be analyzed, designed, and further assembled separately. Component variants are aggregated into generic components, and links between components become generic. The paper presents the essential concepts related to this product family representation, before showing their application to an illustrative industrial case study: a family of signaling relays.
{"title":"An assembly-oriented product family representation for integrated design","authors":"P. D. Lit, J. Danloy, A. Delchambre, J. Henrioud","doi":"10.1109/TRA.2002.807550","DOIUrl":"https://doi.org/10.1109/TRA.2002.807550","url":null,"abstract":"This paper presents a product family representation model which was developed during a research project called CISAL, the purpose of which was to propose an integrated approach for the design of product families and their assembly system. This model is able to deal with partial information from the design of the product family, a situation that often occurs at early stages of the concurrent design of products and production means. The proposed model is assembly-oriented, because the project covered design for assembly, assembly planning, and line layout issues. In fact, it was developed on the basis of the design methodology itself. An originality of the design approach-which impacted the proposed model-is to decompose the product into so-called functional entities defined by the designer. The product family is then seen as an assembly of functional entities that can be analyzed, designed, and further assembled separately. Component variants are aggregated into generic components, and links between components become generic. The paper presents the essential concepts related to this product family representation, before showing their application to an illustrative industrial case study: a family of signaling relays.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114178435","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}
An online method for obtaining smooth, jerk-bounded trajectories has been developed and implemented. Jerk limitation is important in industrial robot applications, since it results in improved path tracking and reduced wear on the robot. The method described herein uses a concatenation of fifth-order polynomials to provide a smooth trajectory between two way points. The trajectory approximates a linear segment with parabolic blends trajectory. A sine wave template is used to calculate the end conditions (control points) for ramps from zero acceleration to nonzero acceleration. Joining these control points with quintic polynomials results in a controlled quintic trajectory that does not oscillate, and is near time optimal for the jerk and acceleration limits specified. The method requires only the computation of the quintic control points, up to a maximum of eight points per trajectory way point. This provides hard bounds for online motion algorithm computation time. A method for blending these straight-line trajectories over a series of way points is also discussed. Simulations and experimental results on an industrial robot are presented.
{"title":"Jerk-bounded manipulator trajectory planning: design for real-time applications","authors":"Sonja E. Macfarlane, E. Croft","doi":"10.1109/TRA.2002.807548","DOIUrl":"https://doi.org/10.1109/TRA.2002.807548","url":null,"abstract":"An online method for obtaining smooth, jerk-bounded trajectories has been developed and implemented. Jerk limitation is important in industrial robot applications, since it results in improved path tracking and reduced wear on the robot. The method described herein uses a concatenation of fifth-order polynomials to provide a smooth trajectory between two way points. The trajectory approximates a linear segment with parabolic blends trajectory. A sine wave template is used to calculate the end conditions (control points) for ramps from zero acceleration to nonzero acceleration. Joining these control points with quintic polynomials results in a controlled quintic trajectory that does not oscillate, and is near time optimal for the jerk and acceleration limits specified. The method requires only the computation of the quintic control points, up to a maximum of eight points per trajectory way point. This provides hard bounds for online motion algorithm computation time. A method for blending these straight-line trajectories over a series of way points is also discussed. Simulations and experimental results on an industrial robot are presented.","PeriodicalId":161449,"journal":{"name":"IEEE Trans. Robotics Autom.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114385542","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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