Pub Date : 2014-09-01DOI: 10.1109/ETFA.2014.7005206
P. Lalanda, Stéphanie Chollet, C. Escoffier, D. Morand
In this paper, we present a distributed and autonomic mediation framework named Cilia, dedicated to complex physical environments like manufacturing plants, electrical infrastructures or smart buildings. We detail a motivating example in these fields and we explain how autonomic features are absolutely necessary in domains characterized by important environmental dynamism and by evolving needs of decision-makers. We also present in detail the main principles of Cilia, including its autonomic abilities. We believe that these autonomic behaviors are necessary to deal with Big Data in industrial contexts. Cilia has been validated in collaborative projects with Orange and Schneider Electric.
{"title":"Dynamic collection of data in complex, physical environments","authors":"P. Lalanda, Stéphanie Chollet, C. Escoffier, D. Morand","doi":"10.1109/ETFA.2014.7005206","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005206","url":null,"abstract":"In this paper, we present a distributed and autonomic mediation framework named Cilia, dedicated to complex physical environments like manufacturing plants, electrical infrastructures or smart buildings. We detail a motivating example in these fields and we explain how autonomic features are absolutely necessary in domains characterized by important environmental dynamism and by evolving needs of decision-makers. We also present in detail the main principles of Cilia, including its autonomic abilities. We believe that these autonomic behaviors are necessary to deal with Big Data in industrial contexts. Cilia has been validated in collaborative projects with Orange and Schneider Electric.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"36 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89322141","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005329
A. Cencen, K. V. Deurzen, J. Verlinden, J. Geraedts
Recently, robots are making their way towards the small and medium enterprises at a quick pace. This is due to market demand and enabled by reduction in costs of robot systems. If robots can be introduced strategically in existing production workflows, productivity could be increased. However, the task division and interaction between human and robot co-workers need to be optimized in order to achieve this. This work-in-progress paper presents a pilot setup to explore such scenarios. We discuss early findings and we present our vision for the future of human robot coproduction.
{"title":"Exploring human robot coproduction","authors":"A. Cencen, K. V. Deurzen, J. Verlinden, J. Geraedts","doi":"10.1109/ETFA.2014.7005329","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005329","url":null,"abstract":"Recently, robots are making their way towards the small and medium enterprises at a quick pace. This is due to market demand and enabled by reduction in costs of robot systems. If robots can be introduced strategically in existing production workflows, productivity could be increased. However, the task division and interaction between human and robot co-workers need to be optimized in order to achieve this. This work-in-progress paper presents a pilot setup to explore such scenarios. We discuss early findings and we present our vision for the future of human robot coproduction.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"4 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88792435","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005119
Jan Kamieth, T. Steinbach, Franz Korf, T. Schmidt
Real-time Ethernet variants gain importance for communication infrastructure of various time-critical domains, such as in-car networks. Synchronous time-triggered traffic guarantees strict timing but requires a detailed schedule for all participants. Designing these schedules by hand is extensive work and with increasing network size almost impossible. In this paper, we contribute a mapping of the time-triggered network scheduling problem into the domain of multiprocessor scheduling. This set of transformation rules allows us to apply established scheduling algorithms as well as new strategies to organise time-triggered switched networks. Experimental results from a prototype implementation of a scheduling framework based on this mapping show the feasibility of our concept. The framework demonstrates a multiple solver approach that uses algorithms with different optimality criteria in parallel.
{"title":"Design of TDMA-based in-car networks: Applying multiprocessor scheduling strategies on time-triggered switched ethernet communication","authors":"Jan Kamieth, T. Steinbach, Franz Korf, T. Schmidt","doi":"10.1109/ETFA.2014.7005119","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005119","url":null,"abstract":"Real-time Ethernet variants gain importance for communication infrastructure of various time-critical domains, such as in-car networks. Synchronous time-triggered traffic guarantees strict timing but requires a detailed schedule for all participants. Designing these schedules by hand is extensive work and with increasing network size almost impossible. In this paper, we contribute a mapping of the time-triggered network scheduling problem into the domain of multiprocessor scheduling. This set of transformation rules allows us to apply established scheduling algorithms as well as new strategies to organise time-triggered switched networks. Experimental results from a prototype implementation of a scheduling framework based on this mapping show the feasibility of our concept. The framework demonstrates a multiple solver approach that uses algorithms with different optimality criteria in parallel.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"37 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79299920","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005328
A. Berger, Alexander Entinger, Albert Potsch, A. Springer
Many applications in factory and process automation require robust wireless sensor networks (WSNs) for collecting sensor data with sampling and transmission rates up to 100 Hz from battery powered sensor nodes. To establish real-time communication in a star network topology, the LLDN mode of IEEE 802.15.4e amendment was released. We present a demonstration system which applies a recently introduced relaying method compatible to the LLDN mode, which uses dedicated relay nodes, thus increasing the reliability of the network while reducing the energy consumption of the sensor nodes. Furthermore, packet combining schemes on packets received erroneously from both, sensor node and relay node, are proposed, applied, and analyzed. Measurements with the demonstration system have shown that 96.4% of these erroneous transmissions could be recovered correctly.
{"title":"Improving IEEE 802.15.4e LLDN performance by relaying and extension of combinatorial testing","authors":"A. Berger, Alexander Entinger, Albert Potsch, A. Springer","doi":"10.1109/ETFA.2014.7005328","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005328","url":null,"abstract":"Many applications in factory and process automation require robust wireless sensor networks (WSNs) for collecting sensor data with sampling and transmission rates up to 100 Hz from battery powered sensor nodes. To establish real-time communication in a star network topology, the LLDN mode of IEEE 802.15.4e amendment was released. We present a demonstration system which applies a recently introduced relaying method compatible to the LLDN mode, which uses dedicated relay nodes, thus increasing the reliability of the network while reducing the energy consumption of the sensor nodes. Furthermore, packet combining schemes on packets received erroneously from both, sensor node and relay node, are proposed, applied, and analyzed. Measurements with the demonstration system have shown that 96.4% of these erroneous transmissions could be recovered correctly.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"32 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78381281","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005192
Marcos Orellana, R. Griñó
The control technique based on infinite-gain resonators also called Adaptive Feedforward Cancellation (AFC) has been used for some years, mainly in continuous time. In this article, finite-gain resonators in discrete time are analyzed and the advantages for their use in practical applications are discussed, from the perspectives of dynamical behavior and computational implementation. The existing design rules for optimizing system robustness are generalized to any kind of resonator, whether of infinite or finite gain. Nowadays, because most practical implementations are carried out by means of digital systems, such as Digital Signal Processors (DSPs), working directly in discrete time is justified, avoiding any problems that may appear when the resonant controllers are discretized by means of approximations from continuous time.
{"title":"Design of discrete-time finite-gain resonators in AFC control","authors":"Marcos Orellana, R. Griñó","doi":"10.1109/ETFA.2014.7005192","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005192","url":null,"abstract":"The control technique based on infinite-gain resonators also called Adaptive Feedforward Cancellation (AFC) has been used for some years, mainly in continuous time. In this article, finite-gain resonators in discrete time are analyzed and the advantages for their use in practical applications are discussed, from the perspectives of dynamical behavior and computational implementation. The existing design rules for optimizing system robustness are generalized to any kind of resonator, whether of infinite or finite gain. Nowadays, because most practical implementations are carried out by means of digital systems, such as Digital Signal Processors (DSPs), working directly in discrete time is justified, avoiding any problems that may appear when the resonant controllers are discretized by means of approximations from continuous time.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"1 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84020718","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005191
Dinh-Khanh Dang, A. Mifdaoui
To reduce the aircraft weight and maintenance costs while guaranteeing system performance and reliability, an alternative avionic communication architecture based on Ultra Wide Band (UWB) and TDMA protocol is proposed to replace the back-up part of safety-critical avionics network. The analysis and performance optimization of such a proposal is tackled as follows. First, appropriate system modeling and timing analysis, using Network Calculus and Integer Linear Programing (ILP) approach, are provided to evaluate the end-to-end delays and verify system predictability. Then, an optimization approach to find the optimal TDMA cycle duration, which minimizes the end-to-end delays, is proposed. Finally, the efficiency of our proposal to enhance the system performance is validated through a realistic avionic case study.
{"title":"Performance optimization of a UWB-based network for safety-critical avionics","authors":"Dinh-Khanh Dang, A. Mifdaoui","doi":"10.1109/ETFA.2014.7005191","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005191","url":null,"abstract":"To reduce the aircraft weight and maintenance costs while guaranteeing system performance and reliability, an alternative avionic communication architecture based on Ultra Wide Band (UWB) and TDMA protocol is proposed to replace the back-up part of safety-critical avionics network. The analysis and performance optimization of such a proposal is tackled as follows. First, appropriate system modeling and timing analysis, using Network Calculus and Integer Linear Programing (ILP) approach, are provided to evaluate the end-to-end delays and verify system predictability. Then, an optimization approach to find the optimal TDMA cycle duration, which minimizes the end-to-end delays, is proposed. Finally, the efficiency of our proposal to enhance the system performance is validated through a realistic avionic case study.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"39 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89552691","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005131
T. Helbig, E. Westkämper, Johannes Hoos
Modularization aims to improve the flexibility and reconfigurability of manufacturing systems. But the effort and complexity required for the coordination of modules increases with the distribution of intelligence. One of the challenges is the identification of subsystems or automation components in modular manufacturing system which is the focus of this paper. The complete identification of a component includes information on the communication channel, the localization of the component and the related process step. As no single identification method is able to gather all aspects of identification, the Manufacturing System Dependency Model (MaSDeM) is introduced which models the dependencies between distributed automation components. This model is based on three layers representing the different perspectives on the system of the involved persons in the development process of a manufacturing system. With the help of this model one single identification fact is sufficient to deduce all the information on the component. This helps to reduce engineering time involved in modular manufacturing systems.
{"title":"Identifying automation components in modular manufacturing systems: A method for modeling dependencies of manufacturing systems","authors":"T. Helbig, E. Westkämper, Johannes Hoos","doi":"10.1109/ETFA.2014.7005131","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005131","url":null,"abstract":"Modularization aims to improve the flexibility and reconfigurability of manufacturing systems. But the effort and complexity required for the coordination of modules increases with the distribution of intelligence. One of the challenges is the identification of subsystems or automation components in modular manufacturing system which is the focus of this paper. The complete identification of a component includes information on the communication channel, the localization of the component and the related process step. As no single identification method is able to gather all aspects of identification, the Manufacturing System Dependency Model (MaSDeM) is introduced which models the dependencies between distributed automation components. This model is based on three layers representing the different perspectives on the system of the involved persons in the development process of a manufacturing system. With the help of this model one single identification fact is sufficient to deduce all the information on the component. This helps to reduce engineering time involved in modular manufacturing systems.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"4 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89980151","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005361
I. Val, F. Casado, P. Rodriguez, A. Arriola
In this paper an FPGA-based wideband wireless channel emulator is presented which is suitable for early evaluation of Wireless Sensor and Actuator Networks in industrial environments. The emulator works in complex baseband and has a 100 MHz-wide RF interface which covers the full Industrial, Scientific and Medical (ISM) band of 2.45 GHz (2.4-2.5 GHz); this allows the direct connection of either custom or commercial WSN nodes to the emulator. The emulator has been deployed on a FPGA where a soft processor has been included, and is able to generate white Gaussian noise, and multipath and Doppler fading effects. In this paper the details of the platform are presented, and validation results are shown for its diverse functionalities. BER and PER values are also presented which have been obtained for AWGN and Rayleigh channels using real WSN nodes connected to the emulator.
{"title":"FPGA-based wideband channel emulator for evaluation of Wireless Sensor Networks in industrial environments","authors":"I. Val, F. Casado, P. Rodriguez, A. Arriola","doi":"10.1109/ETFA.2014.7005361","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005361","url":null,"abstract":"In this paper an FPGA-based wideband wireless channel emulator is presented which is suitable for early evaluation of Wireless Sensor and Actuator Networks in industrial environments. The emulator works in complex baseband and has a 100 MHz-wide RF interface which covers the full Industrial, Scientific and Medical (ISM) band of 2.45 GHz (2.4-2.5 GHz); this allows the direct connection of either custom or commercial WSN nodes to the emulator. The emulator has been deployed on a FPGA where a soft processor has been included, and is able to generate white Gaussian noise, and multipath and Doppler fading effects. In this paper the details of the platform are presented, and validation results are shown for its diverse functionalities. BER and PER values are also presented which have been obtained for AWGN and Rayleigh channels using real WSN nodes connected to the emulator.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"5 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79108428","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005081
A. Mousavi, Cheng-Wei Yang, Cheng Pang, V. Vyatkin
Execution of business processes is an important factor that distinguishes residential and office buildings based on their energy usage. Unlike residential buildings, in offices workflows determine how and when energy-consuming devices have to be utilized. Thus, energy efficient building automation systems for office buildings should take into account the dynamic and unpredictable nature of business processes. However, the existing systems lack this important feature. In this paper, a model for combining automation and business processes is proposed. The model is implemented using IEC 61499 Function Block architecture, multi-agent systems and ontology. The proposed method has been examined in a meeting room scheduling scenario, in which meeting scheduling and automated control of the meeting room equipment have been combined and the energy usage has been measured to evaluate the improvement in efficient use of energy using the proposed model.
{"title":"Energy efficient automation model for office buildings based on ontology, agents and IEC 61499 function blocks","authors":"A. Mousavi, Cheng-Wei Yang, Cheng Pang, V. Vyatkin","doi":"10.1109/ETFA.2014.7005081","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005081","url":null,"abstract":"Execution of business processes is an important factor that distinguishes residential and office buildings based on their energy usage. Unlike residential buildings, in offices workflows determine how and when energy-consuming devices have to be utilized. Thus, energy efficient building automation systems for office buildings should take into account the dynamic and unpredictable nature of business processes. However, the existing systems lack this important feature. In this paper, a model for combining automation and business processes is proposed. The model is implemented using IEC 61499 Function Block architecture, multi-agent systems and ontology. The proposed method has been examined in a meeting room scheduling scenario, in which meeting scheduling and automated control of the meeting room equipment have been combined and the energy usage has been measured to evaluate the improvement in efficient use of energy using the proposed model.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"40 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79114480","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 : 2014-09-01DOI: 10.1109/ETFA.2014.7005078
R. Zeilinger, W. Beer, Albert Mayrhofer, Michael Wesinger
In mechatronics engineering the execution of experiments and tests is an important activity during development of new products and maintenance of released products. Planning and execution of experiments and tests is an essential cost and time factor. To keep the development time short it is necessary to have well-managed processes in the test department and to plan, organize, source out or execute, and document tests and experiments in an efficient and effective way. This paper contains the results of a general survey identifying existing practices, used methods and tools in industry concerning testing and piloting. Seven large-scale companies situated in Upper-Austria took part in this survey. The survey concentrates on established test processes and practices, usage of publicly available test methods, and (re)use of self-developed tests methods. Furthermore, applied practices for documentation of test results, test setup data, and used software/tools for test planning, execution, documentation, and storage were investigated in the survey. The results of the survey show established practices and possible improvement areas for test departments in industrial mechatronics engineering context.
{"title":"A survey on test and piloting practices within the engineering of industrial machines and facilities","authors":"R. Zeilinger, W. Beer, Albert Mayrhofer, Michael Wesinger","doi":"10.1109/ETFA.2014.7005078","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005078","url":null,"abstract":"In mechatronics engineering the execution of experiments and tests is an important activity during development of new products and maintenance of released products. Planning and execution of experiments and tests is an essential cost and time factor. To keep the development time short it is necessary to have well-managed processes in the test department and to plan, organize, source out or execute, and document tests and experiments in an efficient and effective way. This paper contains the results of a general survey identifying existing practices, used methods and tools in industry concerning testing and piloting. Seven large-scale companies situated in Upper-Austria took part in this survey. The survey concentrates on established test processes and practices, usage of publicly available test methods, and (re)use of self-developed tests methods. Furthermore, applied practices for documentation of test results, test setup data, and used software/tools for test planning, execution, documentation, and storage were investigated in the survey. The results of the survey show established practices and possible improvement areas for test departments in industrial mechatronics engineering context.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"22 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84481361","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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