Pub Date : 2019-12-16DOI: 10.14279/tuj.eceasst.78.1087
Julieth Patricia Castellanos Ardila
In some safety-critical domains, the applicable safety standards prescribe a safety lifecycle and process-related requirements. Process plans in accordance with the prescribed requirements are essential pieces of evidence for compliance assessment with such standards. However, providing this evidence is time-consuming and prone-to-error since safety standards are large, natural language-based documents with hundreds of requirements. Besides, a company may have many safety-critical-related processes to be checked. In this paper, we propose a novel approach that combines process modeling and compliance checking capabilities to provide the analysis required to conclude whether a process model corresponds to the model with compliant states. Hitherto, our proposed methodology has been evaluated with academic examples that show the potential benefits of its use.
{"title":"Facilitating Automated Compliance Checking in the Safety-critical Context","authors":"Julieth Patricia Castellanos Ardila","doi":"10.14279/tuj.eceasst.78.1087","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.78.1087","url":null,"abstract":"In some safety-critical domains, the applicable safety standards prescribe a safety lifecycle and process-related requirements. Process plans in accordance with the prescribed requirements are essential pieces of evidence for compliance assessment with such standards. However, providing this evidence is time-consuming and prone-to-error since safety standards are large, natural language-based documents with hundreds of requirements. Besides, a company may have many safety-critical-related processes to be checked. In this paper, we propose a novel approach that combines process modeling and compliance checking capabilities to provide the analysis required to conclude whether a process model corresponds to the model with compliant states. Hitherto, our proposed methodology has been evaluated with academic examples that show the potential benefits of its use.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129907016","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 : 2019-10-21DOI: 10.14279/tuj.eceasst.77.1106
C. Bernardeschi, A. Domenici, S. Saponara
Formal verification may play a central role in the development of safe controllers, such as those found in electric drives or (semi-)autonomous vehicles, whose complexity arises from the coexistence of mechanical and electrical subsystems with sophisticated electronic controllers that must implement high-level control policies according to different driving modes, while optimizing several objectives, such as safety first and foremost, efficiency, and performance among others. Model-driven development resorts to simulation to assess how well the various requirements and constraints are satisfied, but there is a growing awareness that more rigorous methods are needed to achieve the required levels of safety. This paper proposes a conceptual framework for the development of complex systems based on (i) higher-order logic specification, (ii) verification by theorem proving, and (iii) tight integration of verification with model-driven development and simulation. This framework addresses both digital and analog systems, as illustrated with some examples in different fields including implantable biomedical systems, autonomous vehicles, and electric valve actuation.
{"title":"Formal Verification in the Loop to Enhance Verification of Safety-Critical Cyber-physical Systems","authors":"C. Bernardeschi, A. Domenici, S. Saponara","doi":"10.14279/tuj.eceasst.77.1106","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.77.1106","url":null,"abstract":"Formal verification may play a central role in the development of safe controllers, such as those found in electric drives or (semi-)autonomous vehicles, whose complexity arises from the coexistence of mechanical and electrical subsystems with sophisticated electronic controllers that must implement high-level control policies according to different driving modes, while optimizing several objectives, such as safety first and foremost, efficiency, and performance among others. Model-driven development resorts to simulation to assess how well the various requirements and constraints are satisfied, but there is a growing awareness that more rigorous methods are needed to achieve the required levels of safety. This paper proposes a conceptual framework for the development of complex systems based on (i) higher-order logic specification, (ii) verification by theorem proving, and (iii) tight integration of verification with model-driven development and simulation. This framework addresses both digital and analog systems, as illustrated with some examples in different fields including implantable biomedical systems, autonomous vehicles, and electric valve actuation.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127621421","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 : 2019-10-21DOI: 10.14279/tuj.eceasst.77.1109
Robert Husák, J. Kofroň, F. Zavoral
In order to prevent and fix errors in program code, developers need to understand its semantics to a significant extent. For this purpose, they use various approaches, such as manual call graph exploration or dynamic analysis with a debugger. However, these techniques tend to be cumbersome in a larger codebase, because they provide either underapproximate or overapproximate results and it is often hard to combine them. Therefore, we present AskTheCode, a Microsoft Visual Studio extension enabling to interactively explore a call graph, ensuring that only feasible execution traces are taken into consideration. AskTheCode is based on control flow analysis and backward symbolic execution. We show its potential to significantly improve developers' experience on a complex code example.
{"title":"AskTheCode: Interactive Call Graph Exploration for Error Fixing and Prevention","authors":"Robert Husák, J. Kofroň, F. Zavoral","doi":"10.14279/tuj.eceasst.77.1109","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.77.1109","url":null,"abstract":"In order to prevent and fix errors in program code, developers need to understand its semantics to a significant extent. For this purpose, they use various approaches, such as manual call graph exploration or dynamic analysis with a debugger. However, these techniques tend to be cumbersome in a larger codebase, because they provide either underapproximate or overapproximate results and it is often hard to combine them. Therefore, we present AskTheCode, a Microsoft Visual Studio extension enabling to interactively explore a call graph, ensuring that only feasible execution traces are taken into consideration. AskTheCode is based on control flow analysis and backward symbolic execution. We show its potential to significantly improve developers' experience on a complex code example.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131520338","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 : 2019-10-21DOI: 10.14279/tuj.eceasst.77.1104
Pietro Ferrara, A. K. Mandal, Agostino Cortesi, F. Spoto
The Internet of Things (IoT) is a key component for the next disruptive technologies. However, IoT merges together several diverse software layers: embedded, enterprise, and cloud programs interact with each other. In addition, security and privacy vulnerabilities of IoT software might be particularly dangerous due to the pervasiveness and physical nature of these systems. During the last decades, static analysis, and in particular taint analysis, has been widely applied to detect software vulnerabilities. Unfortunately, these analyses assume that software is entirely written in a single programming language, and they are not immediately suitable to detect IoT vulnerabilities where many different software components, written in different programming languages, interact. This paper discusses how to leverage existing static taint analyses to a cross-programming language scenario.
{"title":"Cross-Programming Language Taint Analysis for the IoT Ecosystem","authors":"Pietro Ferrara, A. K. Mandal, Agostino Cortesi, F. Spoto","doi":"10.14279/tuj.eceasst.77.1104","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.77.1104","url":null,"abstract":"The Internet of Things (IoT) is a key component for the next disruptive technologies. However, IoT merges together several diverse software layers: embedded, enterprise, and cloud programs interact with each other. In addition, security and privacy vulnerabilities of IoT software might be particularly dangerous due to the pervasiveness and physical nature of these systems. During the last decades, static analysis, and in particular taint analysis, has been widely applied to detect software vulnerabilities. Unfortunately, these analyses assume that software is entirely written in a single programming language, and they are not immediately suitable to detect IoT vulnerabilities where many different software components, written in different programming languages, interact. This paper discusses how to leverage existing static taint analyses to a cross-programming language scenario.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"159 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133939907","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 : 2019-05-14DOI: 10.14279/tuj.eceasst.76.1070
Eduard Kamburjan
We present a novel notion of deadlock for synchronization on arbitrary boolean conditions and a sound, fully automatic deadlock analysis. Contrary to other approaches, our analysis aims to detect deadlocks caused by faulty system design, rather than implementation bugs. We analyze synchronization on boolean conditions on the fields of an object instead of targeting specific synchronization primitives. As usual, a deadlock is a circular dependency between multiple tasks. A task depends on a second task if the execution of this second task has a side-effect that makes the blocking guard-condition of the first one evaluate to true. This requires an analysis of the computations in a method beyond syntactic properties and we integrate a logical validity calculus to do so.
{"title":"Detecting Deadlocks in Formal System Models with Condition Synchronization","authors":"Eduard Kamburjan","doi":"10.14279/tuj.eceasst.76.1070","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.76.1070","url":null,"abstract":"We present a novel notion of deadlock for synchronization on arbitrary boolean conditions and a sound, fully automatic deadlock analysis. Contrary to other approaches, our analysis aims to detect deadlocks caused by faulty system design, rather than implementation bugs. We analyze synchronization on boolean conditions on the fields of an object instead of targeting specific synchronization primitives. As usual, a deadlock is a circular dependency between multiple tasks. A task depends on a second task if the execution of this second task has a side-effect that makes the blocking guard-condition of the first one evaluate to true. This requires an analysis of the computations in a method beyond syntactic properties and we integrate a logical validity calculus to do so.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114819712","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 : 2019-05-14DOI: 10.14279/tuj.eceasst.76.1072
J. Becker
In the development of safety-critical embedded systems, requirements-driven approaches are widely used. Expressing functional requirements in formal languages enables reasoning and formal testing. This paper proposes the Simplified Universal Pattern (SUP) as an easy to use formalism and compares it to SPS, another commonly used specification pattern system. Consistency is an important property of requirements that can be checked already in early design phases. However, formal definitions of consistency are rare in literature and tent to be either too weak or computationally too complex to be applicable to industrial systems. Therefore this work proposes a new formal consistency notion, called partial consistency, for the SUP that is a trade-off between exhaustiveness and complexity. Partial consistency identifies critical cases and verifies if these cause conflicts between requirements
{"title":"Analyzing Consistency of Formal Requirements","authors":"J. Becker","doi":"10.14279/tuj.eceasst.76.1072","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.76.1072","url":null,"abstract":"In the development of safety-critical embedded systems, requirements-driven approaches are widely used. Expressing functional requirements in formal languages enables reasoning and formal testing. This paper proposes the Simplified Universal Pattern (SUP) as an easy to use formalism and compares it to SPS, another commonly used specification pattern system. Consistency is an important property of requirements that can be checked already in early design phases. However, formal definitions of consistency are rare in literature and tent to be either too weak or computationally too complex to be applicable to industrial systems. Therefore this work proposes a new formal consistency notion, called partial consistency, for the SUP that is a trade-off between exhaustiveness and complexity. Partial consistency identifies critical cases and verifies if these cause conflicts between requirements","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134421515","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 : 2018-10-17DOI: 10.14279/tuj.eceasst.75.1054
Predrag Filipovikj, G. Rodríguez-Navas, C. Seceleanu
Industry relies predominantly on manual peer-review techniques for assessing the correctness of system specifications. However, with the ever increasing size, complexity and intricacy of the specifications, it becomes difficult to assure their correctness with respect to certain criteria such as consistency. To cope with this challenge, a set of techniques based on formal methods, called textit{sanity checks} have been proposed to automatically assess the quality of system specifications in a systematic and rigorous manner. The predominant way of assessing the sanity of system specifications is by model checking, which in literature is reported to be expensive for analysis as it takes a long time for the procedure to terminate. Recently, another approach for checking the consistency of a system's specification using Satisfiability Modulo Theories has been proposed in order to reduce the analysis time. In this paper, we compare the two approaches for consistency analysis, by applying them on a relevant industrial use case, using the same definition for consistency and the same set of requirements. The comparison is carried out with respect to: i) time for generating the model and the latter's complexity, and ii) consistency analysis time. Contrary to the currently available data, our preliminary results show no significant difference in analysis time when applied on the same system specification under the same definition of consistency, but show significant difference in the time of creating the model for analysis.
{"title":"Model-Checking-based vs. SMT-based Consistency Analysis of Industrial Embedded Systems Requirements: Application and Experience","authors":"Predrag Filipovikj, G. Rodríguez-Navas, C. Seceleanu","doi":"10.14279/tuj.eceasst.75.1054","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.75.1054","url":null,"abstract":"Industry relies predominantly on manual peer-review techniques for assessing the correctness of system specifications. However, with the ever increasing size, complexity and intricacy of the specifications, it becomes difficult to assure their correctness with respect to certain criteria such as consistency. To cope with this challenge, a set of techniques based on formal methods, called textit{sanity checks} have been proposed to automatically assess the quality of system specifications in a systematic and rigorous manner. The predominant way of assessing the sanity of system specifications is by model checking, which in literature is reported to be expensive for analysis as it takes a long time for the procedure to terminate. Recently, another approach for checking the consistency of a system's specification using Satisfiability Modulo Theories has been proposed in order to reduce the analysis time. In this paper, we compare the two approaches for consistency analysis, by applying them on a relevant industrial use case, using the same definition for consistency and the same set of requirements. The comparison is carried out with respect to: i) time for generating the model and the latter's complexity, and ii) consistency analysis time. Contrary to the currently available data, our preliminary results show no significant difference in analysis time when applied on the same system specification under the same definition of consistency, but show significant difference in the time of creating the model for analysis.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132098077","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 : 2018-10-17DOI: 10.14279/tuj.eceasst.75.1050
D. Kuehn
In this paper we present an approach to transform models of concrete domains specified with CINCO, a meta-modeling suite, into other CINCO domains. This procedure is demonstrated by transforming Webstory models to DIME applications. The model-to-model transformation increases benefits gained from domain-specific solutions, as shown with the DIME to web application generator, ultimately allowing for Webstories to be deployed and run as web applications.
{"title":"Model-to-Model Transformation in Meta-Modeled CINCO Domains","authors":"D. Kuehn","doi":"10.14279/tuj.eceasst.75.1050","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.75.1050","url":null,"abstract":"In this paper we present an approach to transform models of concrete domains specified with CINCO, a meta-modeling suite, into other CINCO domains. This procedure is demonstrated by transforming Webstory models to DIME applications. The model-to-model transformation increases benefits gained from domain-specific solutions, as shown with the DIME to web application generator, ultimately allowing for Webstories to be deployed and run as web applications.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114803174","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 : 2018-10-17DOI: 10.14279/tuj.eceasst.75.1053
Fayola Peters
Software development produces large amounts of data both from the process, as well as the usage of the software product. Software engineering data science turns this data into actionable insights for improving software quality. However, the processing of this data can raise privacy concerns for organizations, which are obligated by law, regulations and polices, to protect personal and business sensitive data. Early data privacy studies in sub-disciplines of software engineering found that applying privacy algorithms often degraded the usefulness of data. Hence, there is a recognized need for finding a balance between privacy and utility. A survey of data privacy solutions for software engineering data was conducted. Overall, researchers found that a combination of data minimization and obfuscation of data, produced results with high levels of privacy while allowing data to remain useful.
{"title":"On Privacy and Utility while Improving Software Quality","authors":"Fayola Peters","doi":"10.14279/tuj.eceasst.75.1053","DOIUrl":"https://doi.org/10.14279/tuj.eceasst.75.1053","url":null,"abstract":"Software development produces large amounts of data both from the process, as well as the usage of the software product. Software engineering data science turns this data into actionable insights for improving software quality. However, the processing of this data can raise privacy concerns for organizations, which are obligated by law, regulations and polices, to protect personal and business sensitive data. Early data privacy studies in sub-disciplines of software engineering found that applying privacy algorithms often degraded the usefulness of data. Hence, there is a recognized need for finding a balance between privacy and utility. A survey of data privacy solutions for software engineering data was conducted. Overall, researchers found that a combination of data minimization and obfuscation of data, produced results with high levels of privacy while allowing data to remain useful.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123109939","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 : 2018-07-18DOI: 10.14279/TUJ.ECEASST.76.1075.1042
Nicolas Schnepf, Rémi Badonnel, Abdelkader Lahmadi, Stephan Merz
Software-defined networks (SDN) offer a high degree of programmabil-ity for handling and forwarding packets. In particular, they allow network administrators to combine different security functions, such as firewalls, intrusion detection systems, and external services, into security chains designed to prevent or mitigate attacks against end user applications. These chains can benefit from formal techniques for their automated construction and verification. We propose in this paper a rule-based system for automating the composition and configuration of such chains for Android applications. Given the network characterization of an application and the set of permissions it requires, our rules construct an abstract representation of a custom security chain. This representation is then translated into a concrete implementation of the chain in Pyretic, a domain-specific language for programming SDN controllers. We prove that the chains produced by our rules satisfy a number of correctness properties such as the absence of black holes or loops, and shadowing freedom, and that they are coherent with the underlying security policy.
{"title":"Rule-Based Synthesis of Chains of Security Functions for Software-Defined Networks","authors":"Nicolas Schnepf, Rémi Badonnel, Abdelkader Lahmadi, Stephan Merz","doi":"10.14279/TUJ.ECEASST.76.1075.1042","DOIUrl":"https://doi.org/10.14279/TUJ.ECEASST.76.1075.1042","url":null,"abstract":"Software-defined networks (SDN) offer a high degree of programmabil-ity for handling and forwarding packets. In particular, they allow network administrators to combine different security functions, such as firewalls, intrusion detection systems, and external services, into security chains designed to prevent or mitigate attacks against end user applications. These chains can benefit from formal techniques for their automated construction and verification. We propose in this paper a rule-based system for automating the composition and configuration of such chains for Android applications. Given the network characterization of an application and the set of permissions it requires, our rules construct an abstract representation of a custom security chain. This representation is then translated into a concrete implementation of the chain in Pyretic, a domain-specific language for programming SDN controllers. We prove that the chains produced by our rules satisfy a number of correctness properties such as the absence of black holes or loops, and shadowing freedom, and that they are coherent with the underlying security policy.","PeriodicalId":115235,"journal":{"name":"Electron. Commun. Eur. Assoc. Softw. Sci. Technol.","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125799702","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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