Pub Date : 2014-09-01DOI: 10.1109/ETFA.2014.7005093
S. Kubler, Manik Madhikermi, A. Buda, Kary Främling, W. Derigent, André Thomas
Building Information Management systems have started to leverage new kinds of digital information infrastructures that integrate activities related to design, budgeting, scheduling, analysis, material management, and human resources. Companies implementing such systems have no other option today than exchanging information among themselves in a proper and efficient way. Industry foundation classes (IFCs) provide useful information structures for such a data sharing. However they do not specify how to capture, exchange and synchronize the information between distinct entities (i.e. information systems like sensors, servers, smart products...) throughout the building lifecycle. Accordingly, this paper investigates existing messaging protocols in order to identify which one is the most appropriate for supporting building lifecycle management; i.e a flexible protocol that provides sufficiently generic communication interfaces. A platform set up on a university campus based on the selected messaging protocol is then presented. Within this context, the research agenda that should be pursued to develop new techniques and algorithms for optimizing the building energy management is announced.
{"title":"Towards data exchange interoperability in building lifecycle management","authors":"S. Kubler, Manik Madhikermi, A. Buda, Kary Främling, W. Derigent, André Thomas","doi":"10.1109/ETFA.2014.7005093","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005093","url":null,"abstract":"Building Information Management systems have started to leverage new kinds of digital information infrastructures that integrate activities related to design, budgeting, scheduling, analysis, material management, and human resources. Companies implementing such systems have no other option today than exchanging information among themselves in a proper and efficient way. Industry foundation classes (IFCs) provide useful information structures for such a data sharing. However they do not specify how to capture, exchange and synchronize the information between distinct entities (i.e. information systems like sensors, servers, smart products...) throughout the building lifecycle. Accordingly, this paper investigates existing messaging protocols in order to identify which one is the most appropriate for supporting building lifecycle management; i.e a flexible protocol that provides sufficiently generic communication interfaces. A platform set up on a university campus based on the selected messaging protocol is then presented. Within this context, the research agenda that should be pursued to develop new techniques and algorithms for optimizing the building energy management is announced.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"204 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":"75873942","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.2014.7005315
A. Lindo, M. C. Pérez, J. Ureña, D. Gualda, Enrique García, J. M. Villadangos
Smartphone capabilities can significantly enhance mobile and context-aware applications that depend on location information. Whereas outdoor Location Based Services (LBS) are highly developed thanks to GPS, indoor LBS still demand a positioning technology that provides accurate location data. In this paper, an ultrasonic signal acquisition module for fine-grained indoor positioning of portable devices, such as smartphones or tablets, is presented. It is based on a microcontroller that digitizes the signals coming from a set of ultrasonic beacons placed on the ceiling and transfers the data acquired through Bluetooth Wireless Technology to the smartphone, for their consequent processing. All ultrasonic beacons emit simultaneously, each one a different Kasami code which is BPSK modulated with a carrier frequency of 40kHz. At the reception, the proposed module, that can coexist with an unlimited number of receivers, digitizes the analog signal captured by an electret microphone and sends it to the smartphone. Then, the smartphone carries out the correlation of the received signal with the emitted codes and obtains its absolute position by hyperbolic trilateration. Test results show that the proposed system can achieve similar accuracies to conventional ultrasonic based local positioning systems, with the advantage of services of a smartphone.
{"title":"Ultrasonic signal acquisition module for smartphone indoor positioning","authors":"A. Lindo, M. C. Pérez, J. Ureña, D. Gualda, Enrique García, J. M. Villadangos","doi":"10.1109/ETFA.2014.7005315","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005315","url":null,"abstract":"Smartphone capabilities can significantly enhance mobile and context-aware applications that depend on location information. Whereas outdoor Location Based Services (LBS) are highly developed thanks to GPS, indoor LBS still demand a positioning technology that provides accurate location data. In this paper, an ultrasonic signal acquisition module for fine-grained indoor positioning of portable devices, such as smartphones or tablets, is presented. It is based on a microcontroller that digitizes the signals coming from a set of ultrasonic beacons placed on the ceiling and transfers the data acquired through Bluetooth Wireless Technology to the smartphone, for their consequent processing. All ultrasonic beacons emit simultaneously, each one a different Kasami code which is BPSK modulated with a carrier frequency of 40kHz. At the reception, the proposed module, that can coexist with an unlimited number of receivers, digitizes the analog signal captured by an electret microphone and sends it to the smartphone. Then, the smartphone carries out the correlation of the received signal with the emitted codes and obtains its absolute position by hyperbolic trilateration. Test results show that the proposed system can achieve similar accuracies to conventional ultrasonic based local positioning systems, with the advantage of services of a smartphone.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"20 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":"80949643","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.2014.7005330
C. Prehofer, Alois Zoitl
In order to cope with changing markets and reduced product life-cycles production systems need to get more adaptive and allow to easily introduce new products and product variants. Current solutions require that all control equipment need to be modified in such cases. In this work we propose a different approach with a strong separation of basic control of production resources from product specific behavior. The product specific behavior is managed by a central control entity which sends parts of the execution tree required for a certain to thin controllers managing the production resources. With this approach we can on one hand achieve the needed flexibility and at the other hand side achieve the timing requirements of production.
{"title":"Towards flexible and adaptive productions systems based on virtual cloud-based control","authors":"C. Prehofer, Alois Zoitl","doi":"10.1109/ETFA.2014.7005330","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005330","url":null,"abstract":"In order to cope with changing markets and reduced product life-cycles production systems need to get more adaptive and allow to easily introduce new products and product variants. Current solutions require that all control equipment need to be modified in such cases. In this work we propose a different approach with a strong separation of basic control of production resources from product specific behavior. The product specific behavior is managed by a central control entity which sends parts of the execution tree required for a certain to thin controllers managing the production resources. With this approach we can on one hand achieve the needed flexibility and at the other hand side achieve the timing requirements of production.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"5 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":"90856360","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.2014.7005122
Shuai Li, Frank Singhoff, S. Rubini, M. Bourdellès
In this paper, a schedulability test is proposed for tree-shaped transactions with non-immediate tasks. A tree-shaped transaction is a group of precedence dependent tasks, partitioned on different processors, which may release several other tasks upon completion. When there are non-immediate tasks, tasks are not necessarily released immediately upon their predecessor's completion. The schedulability test we propose is based on an existing test that does not handle non-immediate tasks directly. Simulation results show that tighter response time upper-bounds can be accessed when effects of non-immediateness are considered. Our schedulability test is motivated by real industrial TDMA systems developed at Thales, and experimental results show it provides less pessimistic schedulability results compared to current methods used by Thales system engineers.
{"title":"Extending schedulability tests of tree-shaped transactions for TDMA radio protocols","authors":"Shuai Li, Frank Singhoff, S. Rubini, M. Bourdellès","doi":"10.1109/ETFA.2014.7005122","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005122","url":null,"abstract":"In this paper, a schedulability test is proposed for tree-shaped transactions with non-immediate tasks. A tree-shaped transaction is a group of precedence dependent tasks, partitioned on different processors, which may release several other tasks upon completion. When there are non-immediate tasks, tasks are not necessarily released immediately upon their predecessor's completion. The schedulability test we propose is based on an existing test that does not handle non-immediate tasks directly. Simulation results show that tighter response time upper-bounds can be accessed when effects of non-immediateness are considered. Our schedulability test is motivated by real industrial TDMA systems developed at Thales, and experimental results show it provides less pessimistic schedulability results compared to current methods used by Thales system engineers.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"219 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":"90485432","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.2014.7005352
Takao Sato, D. Kurahashi, Toru Yamamoto, N. Araki, Y. Konishi
In this study, a nonlinear system is controlled using a linear adaptive method. A nonlinear system is approximated a linear model at each operating point, and a control law is designed based on the approximated linear model. To obtain a suitable linear model at each operating point, many linear models are simultaneously identified. However, the computation load for identifying many models is considerably heavy. Hence, many linear models are identified using General-Purpose computing on Graphics Processing Units (GPGPU). In this study, the assessment of modeling performance is newly introduced. As a result, the control system is updated only when modeling performance is degraded, and frequent update of a control law can be avoided. Finally, numerical results are shown to demonstrate the effectiveness of the proposed method.
{"title":"Performance-adaptive control system for a hammerstein system using GPGPU","authors":"Takao Sato, D. Kurahashi, Toru Yamamoto, N. Araki, Y. Konishi","doi":"10.1109/ETFA.2014.7005352","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005352","url":null,"abstract":"In this study, a nonlinear system is controlled using a linear adaptive method. A nonlinear system is approximated a linear model at each operating point, and a control law is designed based on the approximated linear model. To obtain a suitable linear model at each operating point, many linear models are simultaneously identified. However, the computation load for identifying many models is considerably heavy. Hence, many linear models are identified using General-Purpose computing on Graphics Processing Units (GPGPU). In this study, the assessment of modeling performance is newly introduced. As a result, the control system is updated only when modeling performance is degraded, and frequent update of a control law can be avoided. Finally, numerical results are shown to demonstrate the effectiveness of the proposed method.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"10 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":"89781960","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.2014.7005110
Stefan Hesse, M. Spehr, S. Gumhold, Rainer Groh
The usage of visual analytics during the analysis of business warehouse calculated key performance indicators is one emerging challenge in modern business applications. On the one hand, a complex network of key performance indicators has to be supervised. On the other hand, within this network only few key performance indicators change obviously within a short period of time. The sole mapping of the complexity of a network of key performance indicators to a graph-based visualization only covers static information and neglects temporal dependencies. We present a new visualization approach for the enrichment of graph-based visualizations of key performance indicator networks by introducing a multi-encoded visualization of additional functional, contextual and temporal information. The should help the user to understand relationships between KPIs and alert him if something is going wrong.
{"title":"Visualizing time-dependent key performance indicator in a graph-based analysis","authors":"Stefan Hesse, M. Spehr, S. Gumhold, Rainer Groh","doi":"10.1109/ETFA.2014.7005110","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005110","url":null,"abstract":"The usage of visual analytics during the analysis of business warehouse calculated key performance indicators is one emerging challenge in modern business applications. On the one hand, a complex network of key performance indicators has to be supervised. On the other hand, within this network only few key performance indicators change obviously within a short period of time. The sole mapping of the complexity of a network of key performance indicators to a graph-based visualization only covers static information and neglects temporal dependencies. We present a new visualization approach for the enrichment of graph-based visualizations of key performance indicator networks by introducing a multi-encoded visualization of additional functional, contextual and temporal information. The should help the user to understand relationships between KPIs and alert him if something is going wrong.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"81 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":"89514228","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.2014.7005103
Naoki Kanagawa, S. Takai
In this paper, we consider a failure diagnosis problem for discrete event systems subject to permanent sensor failures. A notion of diagnosability subject to permanent sensor failures is introduced with respect to a certain nondeterministic observation mask. For its verification, we define an aggregated Mealy automaton with a deterministic and state-dependent observation mask. We show that diagnosability of the aggregated Mealy automaton is equivalent to diagnosability of the original system subject to permanent sensor failures. Then, we present a method for verifying diagnosability of the aggregated Mealy automaton. Moreover, we synthesize a diagnoser for the original system as an online diagnoser.
{"title":"Verification and synthesis for failure diagnosis of discrete event systems subject to permanent sensor failures","authors":"Naoki Kanagawa, S. Takai","doi":"10.1109/ETFA.2014.7005103","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005103","url":null,"abstract":"In this paper, we consider a failure diagnosis problem for discrete event systems subject to permanent sensor failures. A notion of diagnosability subject to permanent sensor failures is introduced with respect to a certain nondeterministic observation mask. For its verification, we define an aggregated Mealy automaton with a deterministic and state-dependent observation mask. We show that diagnosability of the aggregated Mealy automaton is equivalent to diagnosability of the original system subject to permanent sensor failures. Then, we present a method for verifying diagnosability of the aggregated Mealy automaton. Moreover, we synthesize a diagnoser for the original system as an online diagnoser.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"56 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":"85836085","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.2014.7005161
T. Novak, Klaus Pollhammer, H. Zeilinger, Samer Schaat
The intention of a Smart City concept is among other things to increase the energy efficiency of a city. Typically addressed topics are energy management or urban traffic management. Up to now Information and Communication Technology (ICT) measures within a Smart City to increase energy efficiency in public lighting have not been considered in detail. The paper presents an approach of an intelligent streetlight management system being an integral part of a Smart City platform. Field bus technology is used at the field level. Control and monitoring strategies are implemented as web services in the central software. Interoperable interfaces to other parts of the platform are specified. Real-life use cases at test sites in Austria demonstrate the benefits of the system: increased energy efficiency without compromising public safety.
{"title":"Intelligent streetlight management in a smart city","authors":"T. Novak, Klaus Pollhammer, H. Zeilinger, Samer Schaat","doi":"10.1109/ETFA.2014.7005161","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005161","url":null,"abstract":"The intention of a Smart City concept is among other things to increase the energy efficiency of a city. Typically addressed topics are energy management or urban traffic management. Up to now Information and Communication Technology (ICT) measures within a Smart City to increase energy efficiency in public lighting have not been considered in detail. The paper presents an approach of an intelligent streetlight management system being an integral part of a Smart City platform. Field bus technology is used at the field level. Control and monitoring strategies are implemented as web services in the central software. Interoperable interfaces to other parts of the platform are specified. Real-life use cases at test sites in Austria demonstrate the benefits of the system: increased energy efficiency without compromising public safety.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"48 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":"89163620","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.2014.7005232
P. Lindgren, Marcus Lindner, Andreas Lindner, Johan Eriksson, V. Vyatkin
Function Blocks provides a means to model and program industrial control systems. The recently acclaimed IEC 61499 standard allows such system models to be partitioned and executed in a distributed fashion. At device level, such models are traditionally implemented onto programmable logic controllers that underneath have an operating system and a software run-time environment which implies high resource demands. However, there is a current trend to involve small embedded systems (so called Internet of Things devices) integrated into such distributed control systems. To this end, we seek to address the outsets for real-time execution of Function Block based designs onto light-weight controllers (MCUs) with limited resources (memory and CPU). Furthermore, we propose a mapping of the Function Block execution semantics onto the RTFM-kernel, and discuss opportunities for off-line (design time) analysis with respect to response time, overall schedulability and memory requirements.
{"title":"Real-time execution of function blocks for Internet of Things using the RTFM-kernel","authors":"P. Lindgren, Marcus Lindner, Andreas Lindner, Johan Eriksson, V. Vyatkin","doi":"10.1109/ETFA.2014.7005232","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005232","url":null,"abstract":"Function Blocks provides a means to model and program industrial control systems. The recently acclaimed IEC 61499 standard allows such system models to be partitioned and executed in a distributed fashion. At device level, such models are traditionally implemented onto programmable logic controllers that underneath have an operating system and a software run-time environment which implies high resource demands. However, there is a current trend to involve small embedded systems (so called Internet of Things devices) integrated into such distributed control systems. To this end, we seek to address the outsets for real-time execution of Function Block based designs onto light-weight controllers (MCUs) with limited resources (memory and CPU). Furthermore, we propose a mapping of the Function Block execution semantics onto the RTFM-kernel, and discuss opportunities for off-line (design time) analysis with respect to response time, overall schedulability and memory requirements.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"42 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":"80064851","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.2014.7005259
Herbert Prähofer, Roland Schatz, Andreas Grimmer
Dynamic program analysis is a technique which records a program execution for the purpose of analyzing its behavior and building high-level models and views. This paper presents an approach to build a high-level model of the behavior of a PLC program component as observed in a program execution. Based on a deterministic record and replay technique, a model is synthesized which represents the transition behavior, timing information, and input output behavior of the component. Then this model can be used to check other executions of the same or similar programs for compliance with the model. We present the synthesis techniques and two variants of trace analysis algorithms.
{"title":"Behavioral model synthesis of PLC programs from execution traces","authors":"Herbert Prähofer, Roland Schatz, Andreas Grimmer","doi":"10.1109/ETFA.2014.7005259","DOIUrl":"https://doi.org/10.1109/ETFA.2014.7005259","url":null,"abstract":"Dynamic program analysis is a technique which records a program execution for the purpose of analyzing its behavior and building high-level models and views. This paper presents an approach to build a high-level model of the behavior of a PLC program component as observed in a program execution. Based on a deterministic record and replay technique, a model is synthesized which represents the transition behavior, timing information, and input output behavior of the component. Then this model can be used to check other executions of the same or similar programs for compliance with the model. We present the synthesis techniques and two variants of trace analysis algorithms.","PeriodicalId":20477,"journal":{"name":"Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)","volume":"102 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80123851","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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