Pub Date : 2018-09-01DOI: 10.1109/ETFA.2018.8502572
Aravind Ingalalli, Ravish Kumar, S. Bhadra
IEC 61850 and Common Information Model (CIM) (IEC 61968/61970) are predominantly used in smart grid domain to achieve the interoperability. CIM focuses on the organizational structures of different components within the smart grid while IEC 61850 focuses on the structure of information exchanges between field devices and systems. CIM can possibly be used for power system domain ontology and indeed for physical modeling too. On the other hand, the IEC 61850-7-420 defines object classes for assets such as Distributed Energy Resource (DER) which may include solar generation, storage, diesel generators etc., DER unit controllers, and other DER-associated power electronic devices (e.g., inverter). These object classes describe asset-specific attributes such as type of assets, set points, state of charge, limits, and ramp rate etc. While acknowledging the cumbersomeness involved in IEC 61850 engineering, there is a need to develop an easily engineer-able and interoperable system that would achieve the efficient operation of microgrid control system. In this paper, we have modelled a subset of microgrid system using different semantic models and tried to formulate the ontology to achieve an intended interoperable information model. The proposed model generation and deployment would achieve easy integration and autonomous operation of devices from different vendors with different information models.
{"title":"Ontological Formulation of Microgrid Control System for Interoperability","authors":"Aravind Ingalalli, Ravish Kumar, S. Bhadra","doi":"10.1109/ETFA.2018.8502572","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502572","url":null,"abstract":"IEC 61850 and Common Information Model (CIM) (IEC 61968/61970) are predominantly used in smart grid domain to achieve the interoperability. CIM focuses on the organizational structures of different components within the smart grid while IEC 61850 focuses on the structure of information exchanges between field devices and systems. CIM can possibly be used for power system domain ontology and indeed for physical modeling too. On the other hand, the IEC 61850-7-420 defines object classes for assets such as Distributed Energy Resource (DER) which may include solar generation, storage, diesel generators etc., DER unit controllers, and other DER-associated power electronic devices (e.g., inverter). These object classes describe asset-specific attributes such as type of assets, set points, state of charge, limits, and ramp rate etc. While acknowledging the cumbersomeness involved in IEC 61850 engineering, there is a need to develop an easily engineer-able and interoperable system that would achieve the efficient operation of microgrid control system. In this paper, we have modelled a subset of microgrid system using different semantic models and tried to formulate the ontology to achieve an intended interoperable information model. The proposed model generation and deployment would achieve easy integration and autonomous operation of devices from different vendors with different information models.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"55 1","pages":"1391-1398"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85322861","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 : 2018-09-01DOI: 10.1109/etfa.2018.8502570
{"title":"Industrial Communication Technologies and Systems","authors":"","doi":"10.1109/etfa.2018.8502570","DOIUrl":"https://doi.org/10.1109/etfa.2018.8502570","url":null,"abstract":"","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"2014 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86457704","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502600
Konstantinos Katsigiannis, D. Serpanos
MTF -Storm is a highly effective fuzzer for industrial systems employing Modbus/TCP connectivity. It achieves high fault coverage, while offering high performance and quick testing of the System-Under- Test (SUT). Analogously to its predecessor MTF, MTF -Storm operates in 3 phases: reconnaissance, fuzz testing and failure detection. Reconnaissance identifies the memory organization of the SUT and the supported functionality, enabling selection and synthesis of fuzz testing sequences that are effective for the specific SUT. MTF -Storm develops its test sequences systematically, starting with single field tests and proceeding with combined field tests, adopting techniques for automated combinatorial software testing and reducing the test space through partitioning field value ranges. MTF -Storm has been used to evaluate 9 different Modbus/TCP implementations and has identified issues with all of them, ranging from out-of-spec responses to successful denial-of-service attacks and crashes.
{"title":"MTF -Storm: a High Performance Fuzzer for Modbus/TCP","authors":"Konstantinos Katsigiannis, D. Serpanos","doi":"10.1109/ETFA.2018.8502600","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502600","url":null,"abstract":"MTF -Storm is a highly effective fuzzer for industrial systems employing Modbus/TCP connectivity. It achieves high fault coverage, while offering high performance and quick testing of the System-Under- Test (SUT). Analogously to its predecessor MTF, MTF -Storm operates in 3 phases: reconnaissance, fuzz testing and failure detection. Reconnaissance identifies the memory organization of the SUT and the supported functionality, enabling selection and synthesis of fuzz testing sequences that are effective for the specific SUT. MTF -Storm develops its test sequences systematically, starting with single field tests and proceeding with combined field tests, adopting techniques for automated combinatorial software testing and reducing the test space through partitioning field value ranges. MTF -Storm has been used to evaluate 9 different Modbus/TCP implementations and has identified issues with all of them, ranging from out-of-spec responses to successful denial-of-service attacks and crashes.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"29 1","pages":"926-931"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79735642","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502510
Marcus Lindner, J. A. Rivera, Henrik Tjader, P. Lindgren, Johan Eriksson
C programming dominates the mainstream of embedded development as of today. To aid the development, hardware abstractions, libraries, kernels, and light-weight operating systems are commonplace. However, these typically offer little or no help to automatic worst-case execution time (WCET) estimation, and thus manual test and measurement based approaches remain the de facto standard. For this paper, we take the outset from the Real-Time For the Masses (RTFM) framework, which is developed to facilitate embedded software development for IoT devices and provides highly efficient implementations, suitable to the mainstream of embedded system design. Although the Rust language plays currently a minor part in embedded development, we believe its properties add significant improvements and thus implement our RTFM framework in Rust. We present an approach to worst-case execution time estimation in the context of RTFM tasks and critical sections, which renders sufficient information for further response time and schedulability analysis. We introduce our test bench, which utilizes the KLEE tool for automatic test vector generation and subsequently performs cycle accurate hardware-in-the-loop measurements of the generated tests. The approach is straightforward and fully automatic. Our solution bridges the gap in between measurement based and static analysis methods for WCET estimation. We demonstrate the feasibility of the approach on a running example throughout the paper and conclude with a discussion on its implications and limitations.
{"title":"Hardware-in-the-loop based WCET analysis with KLEE","authors":"Marcus Lindner, J. A. Rivera, Henrik Tjader, P. Lindgren, Johan Eriksson","doi":"10.1109/ETFA.2018.8502510","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502510","url":null,"abstract":"C programming dominates the mainstream of embedded development as of today. To aid the development, hardware abstractions, libraries, kernels, and light-weight operating systems are commonplace. However, these typically offer little or no help to automatic worst-case execution time (WCET) estimation, and thus manual test and measurement based approaches remain the de facto standard. For this paper, we take the outset from the Real-Time For the Masses (RTFM) framework, which is developed to facilitate embedded software development for IoT devices and provides highly efficient implementations, suitable to the mainstream of embedded system design. Although the Rust language plays currently a minor part in embedded development, we believe its properties add significant improvements and thus implement our RTFM framework in Rust. We present an approach to worst-case execution time estimation in the context of RTFM tasks and critical sections, which renders sufficient information for further response time and schedulability analysis. We introduce our test bench, which utilizes the KLEE tool for automatic test vector generation and subsequently performs cycle accurate hardware-in-the-loop measurements of the generated tests. The approach is straightforward and fully automatic. Our solution bridges the gap in between measurement based and static analysis methods for WCET estimation. We demonstrate the feasibility of the approach on a running example throughout the paper and conclude with a discussion on its implications and limitations.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"05 1","pages":"345-352"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80083923","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502480
Yang Liu, Xin Li
The rapid development of industry 4.0 has promoted the extensive adoption of big data analytics for manufacturing industry. In this domain, virtual metrology is a critical technique that is able to reduce manufacturing cost over a large amount of practical applications. In this paper, we propose a novel tree-based approach for simultaneous feature selection and predictive modeling to facilitate efficient virtual metrology. The proposed method accurately identifies multiple feature sets and then chooses the best candidate to minimize modeling error. As demonstrated by the experimental results based on two industrial examples, the proposed method can achieve higher modeling accuracy and find a more complete feature set than the conventional approach implemented with orthogonal matching pursuit (OMP).
{"title":"Predictive Modeling for Advanced Virtual Metrology: A Tree-Based Approach","authors":"Yang Liu, Xin Li","doi":"10.1109/ETFA.2018.8502480","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502480","url":null,"abstract":"The rapid development of industry 4.0 has promoted the extensive adoption of big data analytics for manufacturing industry. In this domain, virtual metrology is a critical technique that is able to reduce manufacturing cost over a large amount of practical applications. In this paper, we propose a novel tree-based approach for simultaneous feature selection and predictive modeling to facilitate efficient virtual metrology. The proposed method accurately identifies multiple feature sets and then chooses the best candidate to minimize modeling error. As demonstrated by the experimental results based on two industrial examples, the proposed method can achieve higher modeling accuracy and find a more complete feature set than the conventional approach implemented with orthogonal matching pursuit (OMP).","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"360 1","pages":"845-852"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80224261","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502608
Weili Yan, Jun-Hong Zhou
In this paper, a classification-based anomaly detection model is proposed to detect the aircraft component fault by exploring the historical flight sensor data. Detection of the aircraft component fault is formulated as a classification problem. Firstly, several sensors relevant to the fault are selected using statistical analysis. Secondly, flight phase-based statistical features are extracted using the selected sensors. Thirdly, several important features are selected using correlation analysis with the flight label. Finally, the random forest algorithm is applied to build the fault classification model based on the selected features. Experimental results show the proposed method can detect the component fault earlier than or as early as the current aircraft alarming system.
{"title":"Early Fault Detection of Aircraft Components Using Flight Sensor Data","authors":"Weili Yan, Jun-Hong Zhou","doi":"10.1109/ETFA.2018.8502608","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502608","url":null,"abstract":"In this paper, a classification-based anomaly detection model is proposed to detect the aircraft component fault by exploring the historical flight sensor data. Detection of the aircraft component fault is formulated as a classification problem. Firstly, several sensors relevant to the fault are selected using statistical analysis. Secondly, flight phase-based statistical features are extracted using the selected sensors. Thirdly, several important features are selected using correlation analysis with the flight label. Finally, the random forest algorithm is applied to build the fault classification model based on the selected features. Experimental results show the proposed method can detect the component fault earlier than or as early as the current aircraft alarming system.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"382 1","pages":"1337-1342"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84006410","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502533
Le Anh Dao, Alireza Dehghani Pilehvarani, L. Ferrarini
This paper addresses the problem of sharing a private Electrical energy Storage System (ESS) for thermoelectrical energy management in a group of buildings. Each building is equipped with an ESS which can be used partly or completely by other buildings in the same group. This sharing strategy creates coupling constraints among the controllers of each individual building. In this context, an increment proximal minimization method has been employed to manage the energy flows among the various ESS's through a distributed approach. The local controller of each building employs a Model Predictive Control (MPC) which focuses on balancing economic optimization and occupant comfort while fulfilling various local technical constraints. The proposed technique allows local controllers to operate with maximum autonomy and privacy since, at each iteration, a little amount of information is exchanged between each local controller to a centralized coordination unit. Indeed, only the information related to the coupling constraints is required to exchange with the centralized unit. The most significant advantage of the method is to allow the individual building to exploit effectively not only its own ESS but also any excess power and energy capacity of the ESSs of other buildings. The simulation results show the accuracy and efficiency of the proposed method.
{"title":"A Consensus-Based Distributed MPC Approach for Batteries Sharing in Group of Buildings","authors":"Le Anh Dao, Alireza Dehghani Pilehvarani, L. Ferrarini","doi":"10.1109/ETFA.2018.8502533","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502533","url":null,"abstract":"This paper addresses the problem of sharing a private Electrical energy Storage System (ESS) for thermoelectrical energy management in a group of buildings. Each building is equipped with an ESS which can be used partly or completely by other buildings in the same group. This sharing strategy creates coupling constraints among the controllers of each individual building. In this context, an increment proximal minimization method has been employed to manage the energy flows among the various ESS's through a distributed approach. The local controller of each building employs a Model Predictive Control (MPC) which focuses on balancing economic optimization and occupant comfort while fulfilling various local technical constraints. The proposed technique allows local controllers to operate with maximum autonomy and privacy since, at each iteration, a little amount of information is exchanged between each local controller to a centralized coordination unit. Indeed, only the information related to the coupling constraints is required to exchange with the centralized unit. The most significant advantage of the method is to allow the individual building to exploit effectively not only its own ESS but also any excess power and energy capacity of the ESSs of other buildings. The simulation results show the accuracy and efficiency of the proposed method.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"60 1","pages":"871-878"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82959327","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502647
M. Kaspar, Jürgen Bock, Y. Kogan, P. Venet, Michael Weser, U. Zimmermann
We present a way of modelling device functionality in an OPC VA information model, leveraging the OPC UA programs specification. This allows for tool-independent orchestration of distributed and heterogeneous devices, while legacy devices can easily be included into the system by creating an OPC VA wrapper according to our specification.1
{"title":"Tool and Technology Independent Function Interfaces by Using a Generic OPC UA Representation","authors":"M. Kaspar, Jürgen Bock, Y. Kogan, P. Venet, Michael Weser, U. Zimmermann","doi":"10.1109/ETFA.2018.8502647","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502647","url":null,"abstract":"We present a way of modelling device functionality in an OPC VA information model, leveraging the OPC UA programs specification. This allows for tool-independent orchestration of distributed and heterogeneous devices, while legacy devices can easily be included into the system by creating an OPC VA wrapper according to our specification.1","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"17 1","pages":"1183-1186"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82792402","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502573
Marcos A. Pisching, Marcosiris A. O. Pessoa, F. Junqueira, P. E. Miyagi
The Industry 4.0 is changing the scenario of production systems by the information and communication technologies (ICT), Cyber-Physical Systems (CPS), Internet of Things (IoT) to provide on-demand and personalized goods and services. In this context, to guide the development of Industry 4.0 systems was designed a reference architecture model for Industry 4.0 (RAMI 4.0). However, the RAMI 4.0 is in early stage, consequently requiring formal techniques to model and specify the components involved in Industry 4.0 systems. Therefore, this paper introduces the use of the formal technique derived from Petri net (PN) called Production Flow Schema (PFS) as a procedure for the analysis and specification of the parts that compose RAMI 4.0. To exemplify the proposal effectiveness, a modular productive system (MPS) is used as an application case.
{"title":"PFS/PN Technique to Model Industry 4.0 Systems Based on RAMI 4.0","authors":"Marcos A. Pisching, Marcosiris A. O. Pessoa, F. Junqueira, P. E. Miyagi","doi":"10.1109/ETFA.2018.8502573","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502573","url":null,"abstract":"The Industry 4.0 is changing the scenario of production systems by the information and communication technologies (ICT), Cyber-Physical Systems (CPS), Internet of Things (IoT) to provide on-demand and personalized goods and services. In this context, to guide the development of Industry 4.0 systems was designed a reference architecture model for Industry 4.0 (RAMI 4.0). However, the RAMI 4.0 is in early stage, consequently requiring formal techniques to model and specify the components involved in Industry 4.0 systems. Therefore, this paper introduces the use of the formal technique derived from Petri net (PN) called Production Flow Schema (PFS) as a procedure for the analysis and specification of the parts that compose RAMI 4.0. To exemplify the proposal effectiveness, a modular productive system (MPS) is used as an application case.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"90 1","pages":"1153-1156"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81009524","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 : 2018-09-01DOI: 10.1109/ETFA.2018.8502559
G. Kalogeras, C. Koulamas, A. Kalogeras, A. Moronis
Software models that simulate the energy performance and behavior of buildings provide experts, engineers and building administrators with a powerful predictive tool that allows users to analyze and predict the future impact of a possible energy saving measure without any costly physical intervention or the need for measurements. To achieve this, models have to be validated and tested for precision robustness, in order to be able to maintain an acceptable predictive capability. The present work deals with the implementation a calculation-based monthly quasi-steady state simulation model for energy use in buildings based on the ISO 13790 standard methodologies and presents its robustness testing methodology.
{"title":"Precision Robustness Testing of a Simulation Model for Energy Use in Buildings","authors":"G. Kalogeras, C. Koulamas, A. Kalogeras, A. Moronis","doi":"10.1109/ETFA.2018.8502559","DOIUrl":"https://doi.org/10.1109/ETFA.2018.8502559","url":null,"abstract":"Software models that simulate the energy performance and behavior of buildings provide experts, engineers and building administrators with a powerful predictive tool that allows users to analyze and predict the future impact of a possible energy saving measure without any costly physical intervention or the need for measurements. To achieve this, models have to be validated and tested for precision robustness, in order to be able to maintain an acceptable predictive capability. The present work deals with the implementation a calculation-based monthly quasi-steady state simulation model for energy use in buildings based on the ISO 13790 standard methodologies and presents its robustness testing methodology.","PeriodicalId":6566,"journal":{"name":"2018 IEEE 23rd International Conference on Emerging Technologies and Factory Automation (ETFA)","volume":"41 1","pages":"932-939"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90544831","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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