Pub Date : 2016-05-01DOI: 10.1109/WODES.2016.7497878
Julien Niguez, S. Amari, J. Faure
In this paper, we propose a new linear representation to model the behavior of Timed Automata with Guards (TAGs) using the formalism of dioids algebra. This linear modeling is used to define the parallel composition and properties of determinism for TAGs. The contribution is illustrated with an example of a jobshop to analyze the performances of this system.
{"title":"Analysis of Timed Automata with Guards in dioids algebra","authors":"Julien Niguez, S. Amari, J. Faure","doi":"10.1109/WODES.2016.7497878","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497878","url":null,"abstract":"In this paper, we propose a new linear representation to model the behavior of Timed Automata with Guards (TAGs) using the formalism of dioids algebra. This linear modeling is used to define the parallel composition and properties of determinism for TAGs. The contribution is illustrated with an example of a jobshop to analyze the performances of this system.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124159870","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497869
Xianghu Meng, Jun Li, Xiangzhong Dai
The colored traveling salesman problem (CTSP) is a generalization of the well-known multiple traveling salesman problem. In CTSP, each salesman is allocated a particular color and each city carrying one to all salesmen' colors allows any salesman of the same color to visit exactly once. There are two strategies to address CTSP, i.e., the direct and transformed. The former is to solve a CTSP directly while the latter addresses it by decomposing it into simpler sub-problems first. Given a CTSP with different city color distribution, the solutions obtained by them may be different. We consider that there should be a certain regularity for selecting a proper solution strategy for a CTSP according to its city color distribution. This paper focuses on investigating such a regularity and establishes some principles for the solution strategies selection. First, we propose a city coloring scheme and algorithm for allocating proportionally different colors to the cities in each cluster. Then, we define a color dispersion degree as the percentage of color-changed cities in each city cluster. Finally, some experiments are conducted to track the regularity for selecting a proper strategy for solving a CTSP according to its city color distribution. The results show that the more scattered the city color distribution, the better the solution achieved by the direct strategy, using the same genetic algorithm. Also, it suggests that the solution algorithm combined with proximity operations, e.g., greedy operation, can efficiently accommodate the fluctuating city color distribution in CTSP.
{"title":"Selection of solution strategies for colored traveling salesman problems with different city distribution","authors":"Xianghu Meng, Jun Li, Xiangzhong Dai","doi":"10.1109/WODES.2016.7497869","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497869","url":null,"abstract":"The colored traveling salesman problem (CTSP) is a generalization of the well-known multiple traveling salesman problem. In CTSP, each salesman is allocated a particular color and each city carrying one to all salesmen' colors allows any salesman of the same color to visit exactly once. There are two strategies to address CTSP, i.e., the direct and transformed. The former is to solve a CTSP directly while the latter addresses it by decomposing it into simpler sub-problems first. Given a CTSP with different city color distribution, the solutions obtained by them may be different. We consider that there should be a certain regularity for selecting a proper solution strategy for a CTSP according to its city color distribution. This paper focuses on investigating such a regularity and establishes some principles for the solution strategies selection. First, we propose a city coloring scheme and algorithm for allocating proportionally different colors to the cities in each cluster. Then, we define a color dispersion degree as the percentage of color-changed cities in each city cluster. Finally, some experiments are conducted to track the regularity for selecting a proper strategy for solving a CTSP according to its city color distribution. The results show that the more scattered the city color distribution, the better the solution achieved by the direct strategy, using the same genetic algorithm. Also, it suggests that the solution algorithm combined with proximity operations, e.g., greedy operation, can efficiently accommodate the fluctuating city color distribution in CTSP.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129625674","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497843
Ahmed Al-Ajeli, B. Bordbar
This paper presents a new technique for failure diagnosis in partially observable discrete event systems modelled as Petri nets. In this new technique we adopt Integer Fourier-Motzkin Elimination (IFME) method. We start with a Petri net and produce the state equations. The state equations are a set of integer valued inequalities in variables that represent number of firing of transitions. Occurrences of failure can also be expressed by inequalities. Then we extend the set of inequalities obtained from the state equations to two new sets. The first is created from adding the inequality for failure. The second is created from adding the negation of the inequality for failure. Applying the IFME method to the two resulting sets of inequalities, the variables corresponding to unobservable transitions will be eliminated. Then we prove that for acyclic Petri nets, the reduced set of inequalities after the elimination can be used to diagnose failures.
{"title":"Fourier-Motzkin method for failure diagnosis in Petri Net models of discrete event systems","authors":"Ahmed Al-Ajeli, B. Bordbar","doi":"10.1109/WODES.2016.7497843","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497843","url":null,"abstract":"This paper presents a new technique for failure diagnosis in partially observable discrete event systems modelled as Petri nets. In this new technique we adopt Integer Fourier-Motzkin Elimination (IFME) method. We start with a Petri net and produce the state equations. The state equations are a set of integer valued inequalities in variables that represent number of firing of transitions. Occurrences of failure can also be expressed by inequalities. Then we extend the set of inequalities obtained from the state equations to two new sets. The first is created from adding the inequality for failure. The second is created from adding the negation of the inequality for failure. Applying the IFME method to the two resulting sets of inequalities, the variables corresponding to unobservable transitions will be eliminated. Then we prove that for acyclic Petri nets, the reduced set of inequalities after the elimination can be used to diagnose failures.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132292654","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497849
Burak Demirel, V. Gupta, D. Quevedo, M. Johansson
This paper considers multiple linear stochastic control systems whose feedback loops are closed over a shared communication medium. A threshold-based event-triggering rule is used to transmit control commands from the controllers to the actuators, and network access is arbitrated using a static priority mechanism. Under these conditions, we study dead-beat control laws and compute the expected linear-quadratic loss of the closed-loop system as a function of the event-thresholds of the individual loops. Also, we present analytical expressions that quantify the trade-off between the communication cost and the control performance of such event-triggered control systems. Using a multi-dimensional exhaustive search method, we determine the set of event thresholds that attains the minimal expected linear-quadratic loss of the closed-loop systems. Simulation studies highlight the trade-off between the communication and control cost.
{"title":"Threshold optimization of event-triggered multi-loop control systems","authors":"Burak Demirel, V. Gupta, D. Quevedo, M. Johansson","doi":"10.1109/WODES.2016.7497849","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497849","url":null,"abstract":"This paper considers multiple linear stochastic control systems whose feedback loops are closed over a shared communication medium. A threshold-based event-triggering rule is used to transmit control commands from the controllers to the actuators, and network access is arbitrated using a static priority mechanism. Under these conditions, we study dead-beat control laws and compute the expected linear-quadratic loss of the closed-loop system as a function of the event-thresholds of the individual loops. Also, we present analytical expressions that quantify the trade-off between the communication cost and the control performance of such event-triggered control systems. Using a multi-dimensional exhaustive search method, we determine the set of event thresholds that attains the minimal expected linear-quadratic loss of the closed-loop systems. Simulation studies highlight the trade-off between the communication and control cost.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128171423","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497828
N. Sundström, B. Lennartson
Rescheduling is used to minimize the impact on the system performance when disruptions are present. Affected operations rescheduling (AOR), is often mentioned in the literature on rescheduling. This method generates an initial deterministic job shop schedule offline, which is updated online in response to machine breakdowns. Only operations directly or indirectly affected by a disrupt is rescheduled. In this paper, we formulate a purely offline AOR approach for job shops. Based on a time-optimal schedule, the proposed method generates sequence-based constraints resulting in the same system performance. The realized schedule is identical for both approaches. Also, the proposed approach applies to any disrupt that might cause delays in the system. In right-shift rescheduling (RSR), all remaining operations are postponed if disrupts occur. A formal proof is presented to show that AOR will always perform better than or equal to RSR in the face of disruptions. For analyzing the effect of disrupts, an analytical measure of the makespan is introduced, which depends on possible delays in the system.
{"title":"Rescheduling affected operations - a purely predictive approach","authors":"N. Sundström, B. Lennartson","doi":"10.1109/WODES.2016.7497828","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497828","url":null,"abstract":"Rescheduling is used to minimize the impact on the system performance when disruptions are present. Affected operations rescheduling (AOR), is often mentioned in the literature on rescheduling. This method generates an initial deterministic job shop schedule offline, which is updated online in response to machine breakdowns. Only operations directly or indirectly affected by a disrupt is rescheduled. In this paper, we formulate a purely offline AOR approach for job shops. Based on a time-optimal schedule, the proposed method generates sequence-based constraints resulting in the same system performance. The realized schedule is identical for both approaches. Also, the proposed approach applies to any disrupt that might cause delays in the system. In right-shift rescheduling (RSR), all remaining operations are postponed if disrupts occur. A formal proof is presented to show that AOR will always perform better than or equal to RSR in the face of disruptions. For analyzing the effect of disrupts, an analytical measure of the makespan is introduced, which depends on possible delays in the system.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114476040","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497842
J. Fraustro-Valdez, J. Ruiz-León, C. Vázquez, A. Ramírez-Treviño
This work addresses the fault detection and isolation problem in systems modeled by Timed Continuous Petri Nets (TCPN) under the infinite server semantics. The proposed approach assumes that the normal behavior TCPN model is available and partially observed (i.e., only the marking of a subset of places is available). Potential product rejection faults and speed reduction faults are represented by transitions, whose firing characterize the occurrence of the corresponding faults. Based on this model, a novel structural characterization of diagnosable TCPN is presented. This characterization is based on the structural observability of places belonging to directed paths, between measurable places, containing information about the firing of the fault transitions. In order to isolate faults, a diagnoser is also proposed in this work. The diagnoser is based on a set of robust reduced order finite-time observers. The faults are isolated using internal signals in the observers that are different from zero when a specific fault occurs.
{"title":"Structural fault diagnosis in Timed Continuous Petri Nets","authors":"J. Fraustro-Valdez, J. Ruiz-León, C. Vázquez, A. Ramírez-Treviño","doi":"10.1109/WODES.2016.7497842","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497842","url":null,"abstract":"This work addresses the fault detection and isolation problem in systems modeled by Timed Continuous Petri Nets (TCPN) under the infinite server semantics. The proposed approach assumes that the normal behavior TCPN model is available and partially observed (i.e., only the marking of a subset of places is available). Potential product rejection faults and speed reduction faults are represented by transitions, whose firing characterize the occurrence of the corresponding faults. Based on this model, a novel structural characterization of diagnosable TCPN is presented. This characterization is based on the structural observability of places belonging to directed paths, between measurable places, containing information about the firing of the fault transitions. In order to isolate faults, a diagnoser is also proposed in this work. The diagnoser is based on a set of robust reduced order finite-time observers. The faults are isolated using internal signals in the observers that are different from zero when a specific fault occurs.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128306936","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497844
P. Li, M. Khlif-Bouassida, A. Toguyéni
This paper addresses the combinatorial explosion problem for diagnosability analysis of discrete event systems (DESs). Some reduction rules are given to simplify a priori the labeled Petri net (LPN) model before analyzing the diagnosability. When the conditions of these reduction rules are satisfied, some regular unobservable transitions and some places, that do not contain necessary information for the diagnosability analysis, are removed. It is proved the diagnosability of the initial LPN is preserved by using these reduction rules. In this paper, the “diagnoser” approach is used to compare the diagnosability analysis of the initial LPN model and that of the reduced LPN model. By using reduction rules, the memory cost for diagnosability analysis is reduced.
{"title":"Diagnosis and diagnosability analysis of labeled Petri nets using reduction rules","authors":"P. Li, M. Khlif-Bouassida, A. Toguyéni","doi":"10.1109/WODES.2016.7497844","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497844","url":null,"abstract":"This paper addresses the combinatorial explosion problem for diagnosability analysis of discrete event systems (DESs). Some reduction rules are given to simplify a priori the labeled Petri net (LPN) model before analyzing the diagnosability. When the conditions of these reduction rules are satisfied, some regular unobservable transitions and some places, that do not contain necessary information for the diagnosability analysis, are removed. It is proved the diagnosability of the initial LPN is preserved by using these reduction rules. In this paper, the “diagnoser” approach is used to compare the diagnosability analysis of the initial LPN model and that of the reduced LPN model. By using reduction rules, the memory cost for diagnosability analysis is reduced.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129591004","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497886
M. Zgorzelski, J. Lunze
This paper describes networked discrete-event systems as a set of controlled subsystems, which are physically and digitally connected. The controlled subsystems have two operation modes: In the autonomous mode they achieve local tasks independently of each other, whereas in the synchronisation mode they perform given tasks synchronously by using communication. The paper proposes to model the networked discrete-event system by an Input/Ouput (I/O) automata network and gives a method for partial cooperation between the controlled subsystems. A tracking control architecture, which has been previously published for centralized systems, is extended to cope with the physical interconnections and the digital communications with other controllers. It is proved that the resulting networked tracking controller guarantees autonomous and partially cooperative behaviour. These results are demonstrated by means of an example featuring a flexible manufacturing system.
{"title":"A method for the synchronisation of networked discrete-event systems","authors":"M. Zgorzelski, J. Lunze","doi":"10.1109/WODES.2016.7497886","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497886","url":null,"abstract":"This paper describes networked discrete-event systems as a set of controlled subsystems, which are physically and digitally connected. The controlled subsystems have two operation modes: In the autonomous mode they achieve local tasks independently of each other, whereas in the synchronisation mode they perform given tasks synchronously by using communication. The paper proposes to model the networked discrete-event system by an Input/Ouput (I/O) automata network and gives a method for partial cooperation between the controlled subsystems. A tracking control architecture, which has been previously published for centralized systems, is extended to cope with the physical interconnections and the digital communications with other controllers. It is proved that the resulting networked tracking controller guarantees autonomous and partially cooperative behaviour. These results are demonstrated by means of an example featuring a flexible manufacturing system.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125289068","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497823
Fabio L. Baldissera, J. Cury
Controlling the dynamics of intracellular networks has many important applications in Biotechnology and Medicine. In a previous work, we presented a method based on the Supervisory Control Theory to find a control law capable of guiding a given gene regulatory network from an initial state to some predefined target state. The controller was assumed to be implemented by synthetic genes. Our approach was entirely developed in the discrete-event domain. In this paper, we show that our ideas can also be employed to find continuous control laws for gene regulatory networks modeled by ordinary differential equations. Hence, we: a) enlarge the range of application of our initial ideas to encompass continuous models traditionally used by the Systems Biology community; and b) make it possible to refine the dynamic specifications of the synthetic genes that act as controllers.
{"title":"Computing continuous control laws for gene regulatory networks within a discrete-event systems approach","authors":"Fabio L. Baldissera, J. Cury","doi":"10.1109/WODES.2016.7497823","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497823","url":null,"abstract":"Controlling the dynamics of intracellular networks has many important applications in Biotechnology and Medicine. In a previous work, we presented a method based on the Supervisory Control Theory to find a control law capable of guiding a given gene regulatory network from an initial state to some predefined target state. The controller was assumed to be implemented by synthetic genes. Our approach was entirely developed in the discrete-event domain. In this paper, we show that our ideas can also be employed to find continuous control laws for gene regulatory networks modeled by ordinary differential equations. Hence, we: a) enlarge the range of application of our initial ideas to encompass continuous models traditionally used by the Systems Biology community; and b) make it possible to refine the dynamic specifications of the synthetic genes that act as controllers.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131156670","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 : 2016-05-01DOI: 10.1109/WODES.2016.7497840
S. Ware, R. Su
A common problem in the field of robotics is how to coordinate the motion of multiple robots. As this problem is PSPACE-complete it is generally solved by incomplete algorithms which are computationally tractable but cannot guarantee that a solution will be found even if a solution exists. In this work we use the coordination method of prioritized planning in a (Discrete Event Systems) DES context. We develop and implement an algorithm for using prioritized planning in DES. The algorithm is showned to be an improvement over the standard prioritized planning approach in terms of being capable of finding a valid solution to the multi-robot motion-planning problem in a greater percentage of instances.
{"title":"Incremental scheduling of discrete event systems","authors":"S. Ware, R. Su","doi":"10.1109/WODES.2016.7497840","DOIUrl":"https://doi.org/10.1109/WODES.2016.7497840","url":null,"abstract":"A common problem in the field of robotics is how to coordinate the motion of multiple robots. As this problem is PSPACE-complete it is generally solved by incomplete algorithms which are computationally tractable but cannot guarantee that a solution will be found even if a solution exists. In this work we use the coordination method of prioritized planning in a (Discrete Event Systems) DES context. We develop and implement an algorithm for using prioritized planning in DES. The algorithm is showned to be an improvement over the standard prioritized planning approach in terms of being capable of finding a valid solution to the multi-robot motion-planning problem in a greater percentage of instances.","PeriodicalId":268613,"journal":{"name":"2016 13th International Workshop on Discrete Event Systems (WODES)","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127322840","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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