Pub Date : 2015-05-27DOI: 10.1109/WFCS.2015.7160566
Luis Oliveira, L. Almeida, P. Lima
Small teams of cooperating robots have been shown to benefit from the increased reliability of synchronised message exchanges provided by TDMA-based schemes. However, such schemes may also impose a long propagation delay to communications between non neighbour robots. Such negative impact is further increased by long TDMA rounds, which favour reduced medium utilisation and energy consumption, and by decentralised mesh topologies, which increase the team coverage and layout flexibility. For small size teams, say up to 10 units, it is feasible to set-up a global TDMA framework as well as tracking the instantaneous network topology, making it available to each robot. In this work we use this knowledge to forward packets along their path within each TDMA slot. To that end, we present a novel communication protocol that combines global TDMA and multi-hop routing. It maintains the reliability benefits of the TDMA schemes while strongly reducing the end-to-end propagation delay of interactions between non neighbour robots. We validate our protocol with simulation results using OMNET++. In a worst-case topology scenario we achieved an end-to-end delay that can be as low as 35% that of a traditional TDMA implementation that forwards the packets to the immediate one-hop neighbours, only. In a concrete audio streaming application scenario reported in the literature for an alternative real-time token-passing protocol, our proposal achieves similar delays with significantly less management bandwidth.
{"title":"Multi-hop routing within TDMA slots for teams of cooperating robots","authors":"Luis Oliveira, L. Almeida, P. Lima","doi":"10.1109/WFCS.2015.7160566","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160566","url":null,"abstract":"Small teams of cooperating robots have been shown to benefit from the increased reliability of synchronised message exchanges provided by TDMA-based schemes. However, such schemes may also impose a long propagation delay to communications between non neighbour robots. Such negative impact is further increased by long TDMA rounds, which favour reduced medium utilisation and energy consumption, and by decentralised mesh topologies, which increase the team coverage and layout flexibility. For small size teams, say up to 10 units, it is feasible to set-up a global TDMA framework as well as tracking the instantaneous network topology, making it available to each robot. In this work we use this knowledge to forward packets along their path within each TDMA slot. To that end, we present a novel communication protocol that combines global TDMA and multi-hop routing. It maintains the reliability benefits of the TDMA schemes while strongly reducing the end-to-end propagation delay of interactions between non neighbour robots. We validate our protocol with simulation results using OMNET++. In a worst-case topology scenario we achieved an end-to-end delay that can be as low as 35% that of a traditional TDMA implementation that forwards the packets to the immediate one-hop neighbours, only. In a concrete audio streaming application scenario reported in the literature for an alternative real-time token-passing protocol, our proposal achieves similar delays with significantly less management bandwidth.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"42 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80190479","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160587
Andreas Platschek, B. Thiemann, H. Zeilinger
When argumenting the safety of an industrial system, the validity of the calculation of the residual error rate depends on multiple factors. Examples are a correct and thorough analysis of hazards, a correct estimation of occurrence and on the risk the identified hazards pose. These properties of the analysis have then to be compiled into a sound error model that reflects reality, and can then be used as basis for calculating the residual error rate of the system. One error model for industrial communication networks is given in IEC 61784-3 [1, B.3]. In this paper, this commonly used error model for industrial communication networks is analyzed and its shortcomings are pin-pointed, leading to the question, whether the current model should be scrutinized, not only its parameters. Based on this analysis a new approach on an error model is proposed. This new model has the advantages of more accurately modelling burst errors, and using input parameters that give less reason for discussion as they are widely used in electro magnetic compatibility (EMC) tests for hardware.
{"title":"Modelling burst errors in industrial networks","authors":"Andreas Platschek, B. Thiemann, H. Zeilinger","doi":"10.1109/WFCS.2015.7160587","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160587","url":null,"abstract":"When argumenting the safety of an industrial system, the validity of the calculation of the residual error rate depends on multiple factors. Examples are a correct and thorough analysis of hazards, a correct estimation of occurrence and on the risk the identified hazards pose. These properties of the analysis have then to be compiled into a sound error model that reflects reality, and can then be used as basis for calculating the residual error rate of the system. One error model for industrial communication networks is given in IEC 61784-3 [1, B.3]. In this paper, this commonly used error model for industrial communication networks is analyzed and its shortcomings are pin-pointed, leading to the question, whether the current model should be scrutinized, not only its parameters. Based on this analysis a new approach on an error model is proposed. This new model has the advantages of more accurately modelling burst errors, and using input parameters that give less reason for discussion as they are widely used in electro magnetic compatibility (EMC) tests for hardware.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"31 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88384286","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160588
D. Wesemann, Jens Dunnermann, M. Schaller, Norman Banick, S. Witte
This paper discusses an alternative to common Powerline or Power-over-Ethernet applications, combining a 100BASE-TX-equivalent full duplex communication and simultaneous DC power transmission on one single twisted pair wire. The reduction of wires and connections can potentially ease the modularity and reconfigurability of industrial production installations, if the data communication offers a sufficiently high robustness against influences from the DC power transmission. This part of our research focuses on the necessary electrical adaptations between data and power circuitry and evaluates interference scenarios that are common for industrial fieldbus installations.
{"title":"Less wires — A novel approach on combined power and ethernet transmission on a single, unshielded twisted pair cable","authors":"D. Wesemann, Jens Dunnermann, M. Schaller, Norman Banick, S. Witte","doi":"10.1109/WFCS.2015.7160588","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160588","url":null,"abstract":"This paper discusses an alternative to common Powerline or Power-over-Ethernet applications, combining a 100BASE-TX-equivalent full duplex communication and simultaneous DC power transmission on one single twisted pair wire. The reduction of wires and connections can potentially ease the modularity and reconfigurability of industrial production installations, if the data communication offers a sufficiently high robustness against influences from the DC power transmission. This part of our research focuses on the necessary electrical adaptations between data and power circuitry and evaluates interference scenarios that are common for industrial fieldbus installations.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"2673 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88958007","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160557
Sten Grüner, Julius Pfrommer, Florian Palm
RESTful interfaces are a wide-spread architecture style for webservice implementations and are built upon the resource-oriented approach to decentralized architectures (ROA). REST postulates a set of requirements that are not covered by the OPC Unified Architecture (OPC UA) communication protocol per se. We propose a set of simple extensions to the OPC UA binary protocol that enable RESTful communication. The evaluation shows an order of magnitude improvement in the use of communication resources for sporadic service requests. Additionally, RESTful OPC UA allows applications to profit from the advantages of the resource-oriented architecture style, such as caching and loose application coupling.
{"title":"A RESTful extension of OPC UA","authors":"Sten Grüner, Julius Pfrommer, Florian Palm","doi":"10.1109/WFCS.2015.7160557","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160557","url":null,"abstract":"RESTful interfaces are a wide-spread architecture style for webservice implementations and are built upon the resource-oriented approach to decentralized architectures (ROA). REST postulates a set of requirements that are not covered by the OPC Unified Architecture (OPC UA) communication protocol per se. We propose a set of simple extensions to the OPC UA binary protocol that enable RESTful communication. The evaluation shows an order of magnitude improvement in the use of communication resources for sporadic service requests. Additionally, RESTful OPC UA allows applications to profit from the advantages of the resource-oriented architecture style, such as caching and loose application coupling.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"111 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83453275","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160584
Marina Gutiérrez, W. Steiner, R. Dobrin, S. Punnekkat
Distributed cyber-physical systems are growing in size and functionality and deterministic communication is an important requirement for those systems. The existing solutions based on the time-triggered paradigm pose certain limitations in regards to the configuration. Usually configuration is seen as a one-time event during the installation of the network. Future realtime networks need to be able to adapt more easily to changes in the network. Thus, the configuration becomes an ongoing service, e.g., as for network maintenance and re-configuration to add and remove new, respectively old, equipment. We postulate that configuration will emerge to a continued service that accompanies a real-time network throughout its different life-cycle phases. In this context of evolving and dynamic networks, we introduce the concept of a configuration agent for real-time networks and demonstrate the concept by a realization based on the time triggered paradigm.
{"title":"A configuration agent based on the time-triggered paradigm for real-time networks","authors":"Marina Gutiérrez, W. Steiner, R. Dobrin, S. Punnekkat","doi":"10.1109/WFCS.2015.7160584","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160584","url":null,"abstract":"Distributed cyber-physical systems are growing in size and functionality and deterministic communication is an important requirement for those systems. The existing solutions based on the time-triggered paradigm pose certain limitations in regards to the configuration. Usually configuration is seen as a one-time event during the installation of the network. Future realtime networks need to be able to adapt more easily to changes in the network. Thus, the configuration becomes an ongoing service, e.g., as for network maintenance and re-configuration to add and remove new, respectively old, equipment. We postulate that configuration will emerge to a continued service that accompanies a real-time network throughout its different life-cycle phases. In this context of evolving and dynamic networks, we introduce the concept of a configuration agent for real-time networks and demonstrate the concept by a realization based on the time triggered paradigm.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"4 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85063561","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160575
A. Vick, Christian Horn, Martin Rudorfer, J. Krüger
This paper describes our concept for control of robots and machine tools through a private factory cloud which is dynamically extended by additional public resources. After discussing the opportunities and drawbacks of the virtualization of robot controllers (RC) and software programmable logic controllers (soft-PLC), we present first experiences with the setup of private and public infrastructures. Finally, we introduce our experimental design for investigating the requirements of machine control algorithms regarding availability, dependability and realtime capability in local and public configurations.
{"title":"Control of robots and machine tools with an extended factory cloud","authors":"A. Vick, Christian Horn, Martin Rudorfer, J. Krüger","doi":"10.1109/WFCS.2015.7160575","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160575","url":null,"abstract":"This paper describes our concept for control of robots and machine tools through a private factory cloud which is dynamically extended by additional public resources. After discussing the opportunities and drawbacks of the virtualization of robot controllers (RC) and software programmable logic controllers (soft-PLC), we present first experiences with the setup of private and public infrastructures. Finally, we introduce our experimental design for investigating the requirements of machine control algorithms regarding availability, dependability and realtime capability in local and public configurations.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"3 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80244881","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160567
Julio Cano, Ana Pereira, Luis Oliveira, L. Almeida
The number of mobile devices accessing the Internet is continuously increasing, creating new problems. For example, when many wireless clients try to access the same video stream in the same hot spot, multicast transmission must be used. However, multicast packets are unacknowledged and may present a high loss rate under adverse conditions which may jeopardize the quality of the streaming. In a severe scenario, packet losses may affect all video frames, preventing the clients from receiving the video stream at all. Therefore, we propose a novel reliable multicast protocol, tailored to streaming applications, that also scales to many clients under the same access point. It uses a feedback repeat request mechanism per client and such requests are adequately scheduled by the streaming server. This mechanism, which is the focus of this paper, also allows differentiating the quality of service provided to the clients, polling their feedback independently. We show experimental and simulation results that confirm the desired scalability and reliable streaming, with efficient bandwidth usage. The results also show a clear superiority in mitigating lost packets with respect to other approaches to the same problem, with benefits reaching and even going beyond one order of magnitude in packets recovery.
{"title":"Scheduling feedback for scalability and reliability in a streaming multicast protocol","authors":"Julio Cano, Ana Pereira, Luis Oliveira, L. Almeida","doi":"10.1109/WFCS.2015.7160567","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160567","url":null,"abstract":"The number of mobile devices accessing the Internet is continuously increasing, creating new problems. For example, when many wireless clients try to access the same video stream in the same hot spot, multicast transmission must be used. However, multicast packets are unacknowledged and may present a high loss rate under adverse conditions which may jeopardize the quality of the streaming. In a severe scenario, packet losses may affect all video frames, preventing the clients from receiving the video stream at all. Therefore, we propose a novel reliable multicast protocol, tailored to streaming applications, that also scales to many clients under the same access point. It uses a feedback repeat request mechanism per client and such requests are adequately scheduled by the streaming server. This mechanism, which is the focus of this paper, also allows differentiating the quality of service provided to the clients, polling their feedback independently. We show experimental and simulation results that confirm the desired scalability and reliable streaming, with efficient bandwidth usage. The results also show a clear superiority in mitigating lost packets with respect to other approaches to the same problem, with benefits reaching and even going beyond one order of magnitude in packets recovery.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"152 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76111157","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160564
Odilson T. Valle, C. Montez, G. Araújo, R. Moraes, F. Vasques
The use of cooperative diversity techniques and network coding concepts are promising solutions to improve the communication reliability in industrial Wireless Sensor Networks (WSNs). In this paper, we propose the NetCoDer scheme to address this problem, whose design is based in these concepts. The effectiveness of the NetCoDer scheme is evaluated through both an experimental setup with real WSN nodes and a simulation assessment, comparing its performance against state-of-the-art TDMA-based retransmission techniques.
{"title":"A WSN data retransmission mechanism based on network coding and cooperative relayers","authors":"Odilson T. Valle, C. Montez, G. Araújo, R. Moraes, F. Vasques","doi":"10.1109/WFCS.2015.7160564","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160564","url":null,"abstract":"The use of cooperative diversity techniques and network coding concepts are promising solutions to improve the communication reliability in industrial Wireless Sensor Networks (WSNs). In this paper, we propose the NetCoDer scheme to address this problem, whose design is based in these concepts. The effectiveness of the NetCoDer scheme is evaluated through both an experimental setup with real WSN nodes and a simulation assessment, comparing its performance against state-of-the-art TDMA-based retransmission techniques.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"272 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77703597","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160577
R. Leszczyna, M. Wróbel
The smart grid as a large-scale system of systems has an exceptionally large surface exposed to cyber-attacks, including highly evolved and sophisticated threats such as Advanced Persistent Threats (APT) or Botnets. When addressing this situation the usual cyber security technologies are prerequisite, but not sufficient. The smart grid requires developing and deploying an extensive ICT infrastructure that supports significantly increased situational awareness and enables detailed and precise command and control. The paper presents one of the studies related to the development and deployment of the Situation Awareness Platform for the smart grid, namely the evaluation of open source Security Information and Event Management systems. These systems are the key components of the platform.
{"title":"Evaluation of open source SIEM for situation awareness platform in the smart grid environment","authors":"R. Leszczyna, M. Wróbel","doi":"10.1109/WFCS.2015.7160577","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160577","url":null,"abstract":"The smart grid as a large-scale system of systems has an exceptionally large surface exposed to cyber-attacks, including highly evolved and sophisticated threats such as Advanced Persistent Threats (APT) or Botnets. When addressing this situation the usual cyber security technologies are prerequisite, but not sufficient. The smart grid requires developing and deploying an extensive ICT infrastructure that supports significantly increased situational awareness and enables detailed and precise command and control. The paper presents one of the studies related to the development and deployment of the Situation Awareness Platform for the smart grid, namely the evaluation of open source Security Information and Event Management systems. These systems are the key components of the platform.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"40 4 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91025052","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 : 2015-05-27DOI: 10.1109/WFCS.2015.7160550
I. Val, A. Arriola, Cristina Cruces, Raul Torrego, E. Gomez, Xabier Arizkorreta
In this work a time-synchronized Wireless Sensor Network (WSN) has been designed and implemented for a realtime Structural Health Monitoring (SHM) system for trains. Channel measurements have been done in the first place on a real operational scenario, and obtained results have been used as inputs for the design of the physical layer of the WSN. A specific Time Division Multiple Access (TDMA) MAC layer and a synchronization algorithm have also been developed for allowing a deterministic data collection and synchronized sampling, which are critical aspects in SHM applications. Performance measurements of the WSN have also been done, which have shown maximum sampling synchronization jitter values within 1 μs for sensor nodes belonging the same base station, and maximum jitter values within 2 μs for nodes of different base stations.
{"title":"Time-synchronized Wireless Sensor Network for structural health monitoring applications in railway environments","authors":"I. Val, A. Arriola, Cristina Cruces, Raul Torrego, E. Gomez, Xabier Arizkorreta","doi":"10.1109/WFCS.2015.7160550","DOIUrl":"https://doi.org/10.1109/WFCS.2015.7160550","url":null,"abstract":"In this work a time-synchronized Wireless Sensor Network (WSN) has been designed and implemented for a realtime Structural Health Monitoring (SHM) system for trains. Channel measurements have been done in the first place on a real operational scenario, and obtained results have been used as inputs for the design of the physical layer of the WSN. A specific Time Division Multiple Access (TDMA) MAC layer and a synchronization algorithm have also been developed for allowing a deterministic data collection and synchronized sampling, which are critical aspects in SHM applications. Performance measurements of the WSN have also been done, which have shown maximum sampling synchronization jitter values within 1 μs for sensor nodes belonging the same base station, and maximum jitter values within 2 μs for nodes of different base stations.","PeriodicalId":6531,"journal":{"name":"2015 IEEE World Conference on Factory Communication Systems (WFCS)","volume":"1 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2015-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89735650","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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