Pub Date : 2015-10-26DOI: 10.1109/ETFA.2015.7301643
O. Kovalenko, M. Wimmer, M. Sabou, A. Lüder, F. Ekaputra, S. Biffl
Modeling engineering knowledge explicitly and representing it by means of standardized modeling languages and in machine-understandable form enables advanced engineering processes in industrial and factory automation. This affects positively both process and product quality. In this paper we explore how the AutomationML format, an emerging data exchange standard, that supports the Industry 4.0 vision, can be represented by means of two established modeling approaches - Model-Driven Engineering (MDE) and Semantic Web. We report observed differences w.r.t. resulting model features and model creation process and, additionally, present the application possibilities of the developed models for engineering process improvement in a production system engineering context.
{"title":"Modeling AutomationML: Semantic Web technologies vs. Model-Driven Engineering","authors":"O. Kovalenko, M. Wimmer, M. Sabou, A. Lüder, F. Ekaputra, S. Biffl","doi":"10.1109/ETFA.2015.7301643","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301643","url":null,"abstract":"Modeling engineering knowledge explicitly and representing it by means of standardized modeling languages and in machine-understandable form enables advanced engineering processes in industrial and factory automation. This affects positively both process and product quality. In this paper we explore how the AutomationML format, an emerging data exchange standard, that supports the Industry 4.0 vision, can be represented by means of two established modeling approaches - Model-Driven Engineering (MDE) and Semantic Web. We report observed differences w.r.t. resulting model features and model creation process and, additionally, present the application possibilities of the developed models for engineering process improvement in a production system engineering context.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"75 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90177802","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301559
Lorenzo Bottaccioli, E. Patti, A. Acquaviva, E. Macii, Matteo Jarre, M. Noussan
New approaches and business models for the development of renewable sources are needed as an alternative to feed-in tariffs. In this work, we present a tool-chain based on a distributed infrastructure for planning renewable energy systems deployment. This solution aims at fostering new services and business models by promoting energy community actions. Such tool-chain is able to: (i) evaluate the photovoltaic potential of the rooftops of a community; (ii) perform economic assessments of distributed photovoltaic system plants considering a “community based business model”. As case study, we considered a foothill community in north-west of Italy in which the tool-chain performed economic and energetic analyses. In order to integrate the proposed business model in the Italian regulatory framework, we analysed the Italian laws for electricity distribution and operation, highlighting the limitations in integrating such community approach.
{"title":"A tool-chain to foster a new business model for photovoltaic systems integration exploiting an Energy Community approach","authors":"Lorenzo Bottaccioli, E. Patti, A. Acquaviva, E. Macii, Matteo Jarre, M. Noussan","doi":"10.1109/ETFA.2015.7301559","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301559","url":null,"abstract":"New approaches and business models for the development of renewable sources are needed as an alternative to feed-in tariffs. In this work, we present a tool-chain based on a distributed infrastructure for planning renewable energy systems deployment. This solution aims at fostering new services and business models by promoting energy community actions. Such tool-chain is able to: (i) evaluate the photovoltaic potential of the rooftops of a community; (ii) perform economic assessments of distributed photovoltaic system plants considering a “community based business model”. As case study, we considered a foothill community in north-west of Italy in which the tool-chain performed economic and energetic analyses. In order to integrate the proposed business model in the Italian regulatory framework, we analysed the Italian laws for electricity distribution and operation, highlighting the limitations in integrating such community approach.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"24 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89273463","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301508
Maximilian Wagner, P. Heß, S. Reitelshöfer, J. Franke
This paper describes a method for extrinsic sensor calibration for a 2D laser profile sensor on a robot arm used as a robot based 3D scanning system. In order to establish a relationship between the sensor measurements and the robot positions, the transformation between the robot flange and the sensor reference frame are determined. The developed calibration method is implemented as an automated self-calibration. It is based on the use of a pin as a fixed reference. The robot is aligned to the tip of the pin automatically with certain orientations. The sensor transformation is calculated based on six recorded robot positions. Finally, the accuracy of the calibration is determined with an additional robot position.
{"title":"Self-calibration method for a robotic based 3D scanning system","authors":"Maximilian Wagner, P. Heß, S. Reitelshöfer, J. Franke","doi":"10.1109/ETFA.2015.7301508","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301508","url":null,"abstract":"This paper describes a method for extrinsic sensor calibration for a 2D laser profile sensor on a robot arm used as a robot based 3D scanning system. In order to establish a relationship between the sensor measurements and the robot positions, the transformation between the robot flange and the sensor reference frame are determined. The developed calibration method is implemented as an automated self-calibration. It is based on the use of a pin as a fixed reference. The robot is aligned to the tip of the pin automatically with certain orientations. The sensor transformation is calculated based on six recorded robot positions. Finally, the accuracy of the calibration is determined with an additional robot position.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"1 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84369842","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301539
M. Indri, S. Trapani, Ivan Lazzero
A general procedure for collision detection between an industrial robot and the environment is proposed in this paper. The procedure does not use any external sensor, and does not rely on any particular information about the specific robot on which it is applied, so that it can be easily implemented in the software architecture of different manipulators without any customization. Experimental results on both lightweight and heavyweight industrial manipulators confirm its validity and the absence of false collision detections during standard work-cycles.
{"title":"A general procedure for collision detection between an industrial robot and the environment","authors":"M. Indri, S. Trapani, Ivan Lazzero","doi":"10.1109/ETFA.2015.7301539","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301539","url":null,"abstract":"A general procedure for collision detection between an industrial robot and the environment is proposed in this paper. The procedure does not use any external sensor, and does not rely on any particular information about the specific robot on which it is applied, so that it can be easily implemented in the software architecture of different manipulators without any customization. Experimental results on both lightweight and heavyweight industrial manipulators confirm its validity and the absence of false collision detections during standard work-cycles.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"18 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83732052","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301650
A. Tellaeche, I. Maurtua, A. Ibarguren
Current state of the art in industrial robotics presents highly autonomous production plants, where an undefined number of robots work in cooperation to perform complicated tasks in an automatic way. However, these tasks are repetitive and generally do not allow a minimum change or variation in the overall process to obtain a successful result. In addition to this, these layouts do not allow any fast or easy change in the programmed operation, being not flexible at all. Contrary to this typical industrial situation, current research activities in industrial robotics are focused on human robot interaction and safety, to carry out added value operations that need to be performed both the human and the robot working together. This paper outlines real research cases of this latest type, which have as the final objective their set up in industrial facilities, presenting a review of the current state of the art in human robot interaction to explain, in following sections, successful industrial cases developed in the framework of European Commission Projects.
{"title":"Human robot interaction in industrial robotics. Examples from research centers to industry","authors":"A. Tellaeche, I. Maurtua, A. Ibarguren","doi":"10.1109/ETFA.2015.7301650","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301650","url":null,"abstract":"Current state of the art in industrial robotics presents highly autonomous production plants, where an undefined number of robots work in cooperation to perform complicated tasks in an automatic way. However, these tasks are repetitive and generally do not allow a minimum change or variation in the overall process to obtain a successful result. In addition to this, these layouts do not allow any fast or easy change in the programmed operation, being not flexible at all. Contrary to this typical industrial situation, current research activities in industrial robotics are focused on human robot interaction and safety, to carry out added value operations that need to be performed both the human and the robot working together. This paper outlines real research cases of this latest type, which have as the final objective their set up in industrial facilities, presenting a review of the current state of the art in human robot interaction to explain, in following sections, successful industrial cases developed in the framework of European Commission Projects.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"32 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78852884","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301486
Richard Mordinyi, Philipp Schindler, S. Biffl
In the context of large engineering projects the effective and efficient exchange and versioning of information from different engineering disciplines is essential. Semantic data integration approaches provide the necessary means to overcome the gap between heterogeneous local engineering tool concepts and common project-level concepts which enable the mapping of engineering data coming from different disciplines. However, evaluations have shown that ontology-based stores do not satisfy versioning and query performance criteria in case of large multi-disciplinary engineering projects. In this paper, we present an architecture solution that uses ontologies to describe engineering models and a NoSQL graph database to version individuals. We evaluate the software architectures according to quality attributes, i.e., performance and scalability, in the context of an industrial scenarios, and compare it with related approaches. Main results suggest that the architecture outperforms ontology stores and match solutions relying on relational databases.
{"title":"Evaluation of NoSQL graph databases for querying and versioning of engineering data in multi-disciplinary engineering environments","authors":"Richard Mordinyi, Philipp Schindler, S. Biffl","doi":"10.1109/ETFA.2015.7301486","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301486","url":null,"abstract":"In the context of large engineering projects the effective and efficient exchange and versioning of information from different engineering disciplines is essential. Semantic data integration approaches provide the necessary means to overcome the gap between heterogeneous local engineering tool concepts and common project-level concepts which enable the mapping of engineering data coming from different disciplines. However, evaluations have shown that ontology-based stores do not satisfy versioning and query performance criteria in case of large multi-disciplinary engineering projects. In this paper, we present an architecture solution that uses ontologies to describe engineering models and a NoSQL graph database to version individuals. We evaluate the software architectures according to quality attributes, i.e., performance and scalability, in the context of an industrial scenarios, and compare it with related approaches. Main results suggest that the architecture outperforms ontology stores and match solutions relying on relational databases.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"77 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83194030","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301484
R. Gratia, T. Robert, L. Pautet
Mixed-criticality systems emerged with the aim of reconciling safety requirements and efficient use of multi-processor or uniprocessor platforms. On multi-processors, recent works on mixed-criticality have produced impressive results in terms of speed-up factor. But these solutions, based on Pfair-like scheduling algorithms, entail too many preemptions and migrations to be effectively used in real systems. As RUN is an optimal scheduling algorithm that is known to limit this problem, we propose MxC-RUN, an adaptation of RUN to mixed-criticality systems. We redefine RUN's primal servers as modal servers that allocate the overestimated time budget of their higher criticality tasks to execute lower criticality ones. These servers can be handled by RUN without any modification and preserve its performances in terms of preemptions and migrations. MxC-RUN earns a speed-up factor smaller than other multi-processors EDF-based mixed-criticality scheduling algorithms.
{"title":"Scheduling of mixed-criticality systems with RUN","authors":"R. Gratia, T. Robert, L. Pautet","doi":"10.1109/ETFA.2015.7301484","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301484","url":null,"abstract":"Mixed-criticality systems emerged with the aim of reconciling safety requirements and efficient use of multi-processor or uniprocessor platforms. On multi-processors, recent works on mixed-criticality have produced impressive results in terms of speed-up factor. But these solutions, based on Pfair-like scheduling algorithms, entail too many preemptions and migrations to be effectively used in real systems. As RUN is an optimal scheduling algorithm that is known to limit this problem, we propose MxC-RUN, an adaptation of RUN to mixed-criticality systems. We redefine RUN's primal servers as modal servers that allocate the overestimated time budget of their higher criticality tasks to execute lower criticality ones. These servers can be handled by RUN without any modification and preserve its performances in terms of preemptions and migrations. MxC-RUN earns a speed-up factor smaller than other multi-processors EDF-based mixed-criticality scheduling algorithms.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"9 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89468392","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301443
Linus Thrybom, T. Sivanthi, Y. Pignolet
The process bus communication in substations facilitates the exchange of data from multiple bays to different bay level and station level devices. This enables the realization of applications that depend on data from multiple bays, e.g. Central Synchrocheck. Such applications have high availability and hard real-time requirements. In this paper, different process bus topology variants using the Parallel Redundancy Protocol (PRP) and High-availability Seamless Ring (HSR) for Central Synchrocheck application are investigated. The performance of these topology variants is analyzed under worst-case communication loads for different sizes of substations. To this end, simulation models for Merging Units, Central Synchrocheck device, PRP and HSR network elements are developed in OMNEST. These models are used to build different network topologies. The network topologies are simulated to gather the end-to-end latency statistics for GOOSE and SV messages. The simulation analysis distinguishes the topology variants that offer better performance for a certain substation size and also indicates for which process bus network segments Gigabit Ethernet is appropriate.
{"title":"Performance analysis of process bus communication in a Central Synchrocheck application","authors":"Linus Thrybom, T. Sivanthi, Y. Pignolet","doi":"10.1109/ETFA.2015.7301443","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301443","url":null,"abstract":"The process bus communication in substations facilitates the exchange of data from multiple bays to different bay level and station level devices. This enables the realization of applications that depend on data from multiple bays, e.g. Central Synchrocheck. Such applications have high availability and hard real-time requirements. In this paper, different process bus topology variants using the Parallel Redundancy Protocol (PRP) and High-availability Seamless Ring (HSR) for Central Synchrocheck application are investigated. The performance of these topology variants is analyzed under worst-case communication loads for different sizes of substations. To this end, simulation models for Merging Units, Central Synchrocheck device, PRP and HSR network elements are developed in OMNEST. These models are used to build different network topologies. The network topologies are simulated to gather the end-to-end latency statistics for GOOSE and SV messages. The simulation analysis distinguishes the topology variants that offer better performance for a certain substation size and also indicates for which process bus network segments Gigabit Ethernet is appropriate.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"41 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86449474","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301634
Sinisa Derasevic, M. Barranco, J. Proenza
Distributed embedded systems (DESs) that operate in dynamic environments require emerging flexibility and adaptivity communication requirements. When those DESs are deployed for critical applications, they must also employ appropriate fault-tolerance (FT) mechanisms to attain a high level of reliability. The FTT-Ethernet communication protocol supports the flexibility needed in dynamic environments, but does not provide adequate fault tolerance. In order to overcome this limitation the ongoing FT4FTT project proposes a communication architecture that includes fault-tolerance capabilities at different levels of DESs relying on FTT-Ethernet. In particular, it provides communication and execution mechanisms to tolerate node failures by means of active node replication with majority voting. This paper builds upon a previous OMNET++ model of an FTT-Ethernet-based DES in order to add, simulate and assess those mechanisms. Specifically, it models the communication mechanisms envisaged to enforce replica determinism in the voting procedure, as well as to trigger and coordinate the tasks executed in the replicas.
{"title":"An OMNET++ model to asses node fault-tolerance mechanisms for FTT-Ethernet DESs","authors":"Sinisa Derasevic, M. Barranco, J. Proenza","doi":"10.1109/ETFA.2015.7301634","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301634","url":null,"abstract":"Distributed embedded systems (DESs) that operate in dynamic environments require emerging flexibility and adaptivity communication requirements. When those DESs are deployed for critical applications, they must also employ appropriate fault-tolerance (FT) mechanisms to attain a high level of reliability. The FTT-Ethernet communication protocol supports the flexibility needed in dynamic environments, but does not provide adequate fault tolerance. In order to overcome this limitation the ongoing FT4FTT project proposes a communication architecture that includes fault-tolerance capabilities at different levels of DESs relying on FTT-Ethernet. In particular, it provides communication and execution mechanisms to tolerate node failures by means of active node replication with majority voting. This paper builds upon a previous OMNET++ model of an FTT-Ethernet-based DES in order to add, simulate and assess those mechanisms. Specifically, it models the communication mechanisms envisaged to enforce replica determinism in the voting procedure, as well as to trigger and coordinate the tasks executed in the replicas.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"20 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73435606","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 : 2015-10-26DOI: 10.1109/ETFA.2015.7301440
M. Obst, T. Holm, L. Urbas, A. Fay, Sven Kreft, U. Hempen, T. Albers
The reduction of the effort required for integration of a module into a production plant is the fundamental aim of modular plant architectures. Effective module integration can be achieved, for instance, by shifting engineering efforts from the classical site-engineering to the engineering of plant modules. The basis of this approach is the formal description of various aspects of a module in a module type package (MTP). The core elements of this MTP are presented in this paper and discussed in terms of use in a standard module description. In addition, this paper presents a transformation of this concept to the standardized format AutomationML.
{"title":"Semantic description of process modules","authors":"M. Obst, T. Holm, L. Urbas, A. Fay, Sven Kreft, U. Hempen, T. Albers","doi":"10.1109/ETFA.2015.7301440","DOIUrl":"https://doi.org/10.1109/ETFA.2015.7301440","url":null,"abstract":"The reduction of the effort required for integration of a module into a production plant is the fundamental aim of modular plant architectures. Effective module integration can be achieved, for instance, by shifting engineering efforts from the classical site-engineering to the engineering of plant modules. The basis of this approach is the formal description of various aspects of a module in a module type package (MTP). The core elements of this MTP are presented in this paper and discussed in terms of use in a standard module description. In addition, this paper presents a transformation of this concept to the standardized format AutomationML.","PeriodicalId":6862,"journal":{"name":"2015 IEEE 20th Conference on Emerging Technologies & Factory Automation (ETFA)","volume":"5 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2015-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74874499","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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