Xiaozhen Zhang, W. Kong, Jianguo Jiang, Gang Hou, Akira Fukuda
Craig interpolation has emerged as an effective approximation method and can be widely applied in hardware and software model checking. Since the quality of interpolants can critically affect the success and failure, or convergence and divergence of model checking, researchers have put forward a novel and flexible interpolation abstraction-based technique to guide the computation of promising interpolants. In this technique, abstraction lattice is constructed to arrange families of interpolation abstraction for improving the quality of resulting interpolants. However, the original search strategy to explore an abstraction lattice is not efficient when abstraction lattice enlarges and the elapsed time to perform multiple search on the same abstraction lattice is obviously distinct for many problems. In this paper, in order to alleviate these problems, we propose a top-down search space pruning-based algorithm to search the abstraction lattice and implement this algorithm in the well-known model checker Eldarica. We conduct experiments on 179 benchmarks to compare our algorithm respectively against the original search algorithm in Eldarica and the state-of-the-art SMT solver Z3. The experimental results show that our algorithm performs much better in the sense that it is more efficient than Eldarica for most of the benchmarks and it can solve much more benchmarks than Z3.
{"title":"Steering Interpolants Generation with Efficient Interpolation Abstraction Exploration","authors":"Xiaozhen Zhang, W. Kong, Jianguo Jiang, Gang Hou, Akira Fukuda","doi":"10.1109/TASE.2019.00-11","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-11","url":null,"abstract":"Craig interpolation has emerged as an effective approximation method and can be widely applied in hardware and software model checking. Since the quality of interpolants can critically affect the success and failure, or convergence and divergence of model checking, researchers have put forward a novel and flexible interpolation abstraction-based technique to guide the computation of promising interpolants. In this technique, abstraction lattice is constructed to arrange families of interpolation abstraction for improving the quality of resulting interpolants. However, the original search strategy to explore an abstraction lattice is not efficient when abstraction lattice enlarges and the elapsed time to perform multiple search on the same abstraction lattice is obviously distinct for many problems. In this paper, in order to alleviate these problems, we propose a top-down search space pruning-based algorithm to search the abstraction lattice and implement this algorithm in the well-known model checker Eldarica. We conduct experiments on 179 benchmarks to compare our algorithm respectively against the original search algorithm in Eldarica and the state-of-the-art SMT solver Z3. The experimental results show that our algorithm performs much better in the sense that it is more efficient than Eldarica for most of the benchmarks and it can solve much more benchmarks than Z3.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115192538","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}
The differential of matrix functions(DMF) plays an important role in mathematics and engineering. Common applications of it are found in optimization analysis, computer vision, robotics, etc. In this paper, a formal method based on HOL is used to construct the DMF based on Fréchet differential in matrix space. In order to illustrate the practical effectiveness of our work, we use our formalization to verify a property of matrix exponential.
{"title":"A HOL Theory of the Differential for Matrix Functions","authors":"Yuhan Nie, Zhiping Shi, Aixuan Wu, Ximeng Li, Guohui Wang, Yong Guan","doi":"10.1109/TASE.2019.00-10","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-10","url":null,"abstract":"The differential of matrix functions(DMF) plays an important role in mathematics and engineering. Common applications of it are found in optimization analysis, computer vision, robotics, etc. In this paper, a formal method based on HOL is used to construct the DMF based on Fréchet differential in matrix space. In order to illustrate the practical effectiveness of our work, we use our formalization to verify a property of matrix exponential.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115553932","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}
In this paper, we present a study on building a special SAARA (Self-Aware Automated Reasoning Agent) system for solving Freudenthal's Sum and Product puzzle, aimed to train the "self-reflection" and "subjective experience" abilities as in the Three Wise Men test performed by the Nao robots in Rensselaer Polytechnic Institute in July 2015. We show the dynamic evolution of corresponding knowledge sets in the automated reasoning process for the Sum and Product puzzle.
在本文中，我们研究了构建一个特殊的SAARA (Self-Aware Automated Reasoning Agent)系统来解决Freudenthal的Sum and Product谜题，旨在训练“自我反思”和“主观体验”的能力，就像2015年7月由Rensselaer理工学院的Nao机器人进行的三智人测试一样。我们展示了在求和和积难题的自动推理过程中相应知识集的动态演变。
{"title":"Multi-Agent Automated Reasoning Toward Machine Self-Awareness: A Case Study","authors":"Zhenbing Zeng, Jianlin Wang, Zhengfeng Yang","doi":"10.1109/TASE.2019.00-17","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-17","url":null,"abstract":"In this paper, we present a study on building a special SAARA (Self-Aware Automated Reasoning Agent) system for solving Freudenthal's Sum and Product puzzle, aimed to train the \"self-reflection\" and \"subjective experience\" abilities as in the Three Wise Men test performed by the Nao robots in Rensselaer Polytechnic Institute in July 2015. We show the dynamic evolution of corresponding knowledge sets in the automated reasoning process for the Sum and Product puzzle.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122713575","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}
With the emergence of mobile and adaptive computing, dynamic architectures have become increasingly important. In such architectures, components can appear and disappear, and connections between them can change over time. Verification of such architectures is performed over the composition of its components, which is usually defined in an operational style. Sometimes however, a denotational style might be more convenient for verification. Thus, in the following paper, we propose a denotational semantics for composition in dynamic architectures based on fixed points in lattices. We show that it is well-defined by proving that fixed points are guaranteed to exist. Finally, we use our definition to derive a logical characterization of composition, which forms the basis of a framework for the interactive verification of dynamic architectures.
{"title":"A Denotational Semantics for Dynamic Architectures","authors":"Diego Marmsoler","doi":"10.1109/TASE.2019.000-8","DOIUrl":"https://doi.org/10.1109/TASE.2019.000-8","url":null,"abstract":"With the emergence of mobile and adaptive computing, dynamic architectures have become increasingly important. In such architectures, components can appear and disappear, and connections between them can change over time. Verification of such architectures is performed over the composition of its components, which is usually defined in an operational style. Sometimes however, a denotational style might be more convenient for verification. Thus, in the following paper, we propose a denotational semantics for composition in dynamic architectures based on fixed points in lattices. We show that it is well-defined by proving that fixed points are guaranteed to exist. Finally, we use our definition to derive a logical characterization of composition, which forms the basis of a framework for the interactive verification of dynamic architectures.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114903611","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}
When evaluating Static Application Security Testing (SAST) tools, benchmarks based on real-world softwares are considered more representative than synthetic micro benchmarks. Generated from real-world software, the test cases in such kind of benchmarks usually contain multiple syntactic features which affect the vulnerability detection results reflecting SAST tools' capabilities in real-world settings. However, most existing benchmarks based on real-world software pay little attention to these syntactic features so that only limited information about the capabilities of SAST tools can be obtained from the evaluation results. In this paper, we provide a method of constructing benchmarks and evaluating SAST tools, which leverages the syntactic features to support the evaluation to be more explainable. To demonstrate the effectiveness, we applied our method to the benchmark built by Misha Zitser et al., generated 10 groups of test cases, and evaluated 2 SAST tools with them. The result shows that, with the benchmark constructed by our method, the evaluation could be more explainable which helps us to gain more information about the SAST tools' capabilities of vulnerability detection.
{"title":"Constructing Benchmarks for Supporting Explainable Evaluations of Static Application Security Testing Tools","authors":"Gaojian Hao, Feng Li, Wei Huo, Qing Sun, Wei Wang, Xinhua Li, Wei Zou","doi":"10.1109/TASE.2019.00-18","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-18","url":null,"abstract":"When evaluating Static Application Security Testing (SAST) tools, benchmarks based on real-world softwares are considered more representative than synthetic micro benchmarks. Generated from real-world software, the test cases in such kind of benchmarks usually contain multiple syntactic features which affect the vulnerability detection results reflecting SAST tools' capabilities in real-world settings. However, most existing benchmarks based on real-world software pay little attention to these syntactic features so that only limited information about the capabilities of SAST tools can be obtained from the evaluation results. In this paper, we provide a method of constructing benchmarks and evaluating SAST tools, which leverages the syntactic features to support the evaluation to be more explainable. To demonstrate the effectiveness, we applied our method to the benchmark built by Misha Zitser et al., generated 10 groups of test cases, and evaluated 2 SAST tools with them. The result shows that, with the benchmark constructed by our method, the evaluation could be more explainable which helps us to gain more information about the SAST tools' capabilities of vulnerability detection.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129710083","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}
To BMC of timed automata network, we present a novel time stamp semantics model for timed automata network with synchronization and shared variables, which allows not only mutually independent transitions but also dependent transitions to be compressed together between two states in succession. A key ingredient of our BMC encoding is the use of time stamp variables for shared variable accesses, which are overlooked in previous approaches. The proposed semantics represents the timed automata network in a significantly more compact way than previous step semantics, which allows maximally compressed steps of transitions and therefore is in this sense optimal. A preliminary experimental evaluation shows a significant performance improvement in the number of unrolling of BMC steps and run times as well.
{"title":"Optimized Step Semantics Encoding for Bounded Model Checking of Timed Automata","authors":"Zuxi Chen, Huixing Fang, Xiangyu Luo","doi":"10.1109/TASE.2019.00-14","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-14","url":null,"abstract":"To BMC of timed automata network, we present a novel time stamp semantics model for timed automata network with synchronization and shared variables, which allows not only mutually independent transitions but also dependent transitions to be compressed together between two states in succession. A key ingredient of our BMC encoding is the use of time stamp variables for shared variable accesses, which are overlooked in previous approaches. The proposed semantics represents the timed automata network in a significantly more compact way than previous step semantics, which allows maximally compressed steps of transitions and therefore is in this sense optimal. A preliminary experimental evaluation shows a significant performance improvement in the number of unrolling of BMC steps and run times as well.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130076954","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}
Cyber-physical systems (CPS) are taking a crucial role in various areas of our society and industry. Yet, because of their hybrid nature (i.e. the integration of both continuous and discrete features), their design and verification are not easy to handle, in particular when they are part of a critical system. Their certification requires to exhibit a formal argumentation that formal methods should be able to provide. This paper addresses the formal development of CPS using correct-by-construction refinement and proof based approaches. It relies on the Event-B formal method. In addition to modeling both the discrete and continuous parts of a CPS, this paper presents a novel approach in two steps. First it shows that the generic formal model we have defined, integrating both discrete and continuous behaviors, can be instantiated by various kinds of CPS. Fundamentally, continuous behaviors modeled by differential equations mingle with discrete transition systems (mode automaton), which model discrete behaviors. Here, refinement is used as a decomposition mechanism. Second, it expands the refinement operation, well mastered in the discrete world, to cover continuous behaviors. We show that different levels of abstraction of continuous aspects can be glued in a refinement chain. The proposed approach has been completely formalized using Event-B on the Rodin platform and a case study based on water tanks is used to illustrate it.
{"title":"Handling Refinement of Continuous Behaviors: A Proof Based Approach with Event-B","authors":"G. Dupont, Y. A. Ameur, M. Pantel, N. Singh","doi":"10.1109/TASE.2019.00-25","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-25","url":null,"abstract":"Cyber-physical systems (CPS) are taking a crucial role in various areas of our society and industry. Yet, because of their hybrid nature (i.e. the integration of both continuous and discrete features), their design and verification are not easy to handle, in particular when they are part of a critical system. Their certification requires to exhibit a formal argumentation that formal methods should be able to provide. This paper addresses the formal development of CPS using correct-by-construction refinement and proof based approaches. It relies on the Event-B formal method. In addition to modeling both the discrete and continuous parts of a CPS, this paper presents a novel approach in two steps. First it shows that the generic formal model we have defined, integrating both discrete and continuous behaviors, can be instantiated by various kinds of CPS. Fundamentally, continuous behaviors modeled by differential equations mingle with discrete transition systems (mode automaton), which model discrete behaviors. Here, refinement is used as a decomposition mechanism. Second, it expands the refinement operation, well mastered in the discrete world, to cover continuous behaviors. We show that different levels of abstraction of continuous aspects can be glued in a refinement chain. The proposed approach has been completely formalized using Event-B on the Rodin platform and a case study based on water tanks is used to illustrate it.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133096928","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}
Stutter equivalences are important for system synthesis as well as system analysis. In this paper, we study stutter trace equivalences for Markov automata (MAs) and how they relate to metric temporal logic (MTL) formulas. We first define several variants of stutter trace equivalence for closed MA models. We perform button pushing experiments with a black box model of MA to obtain these equivalences. For every class of MA scheduler, a corresponding variant of stutter trace equivalence is defined. Then we investigate the relationship among these equivalences and also compare them with bisimulation for MAs. Finally, we prove that maximum and minimum probabilities of satisfying properties specified using metric temporal logic (MTL) formulas are preserved under some of these equivalences.
{"title":"Stuttering for Markov Automata","authors":"Arpit Sharma","doi":"10.1109/TASE.2019.000-7","DOIUrl":"https://doi.org/10.1109/TASE.2019.000-7","url":null,"abstract":"Stutter equivalences are important for system synthesis as well as system analysis. In this paper, we study stutter trace equivalences for Markov automata (MAs) and how they relate to metric temporal logic (MTL) formulas. We first define several variants of stutter trace equivalence for closed MA models. We perform button pushing experiments with a black box model of MA to obtain these equivalences. For every class of MA scheduler, a corresponding variant of stutter trace equivalence is defined. Then we investigate the relationship among these equivalences and also compare them with bisimulation for MAs. Finally, we prove that maximum and minimum probabilities of satisfying properties specified using metric temporal logic (MTL) formulas are preserved under some of these equivalences.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116238260","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}
Software transactional memory (STM) provides programmers with a high-level programming abstraction for synchronization of parallel processes, allowing blocks of codes that execute in an interleaved manner to be treated as an atomic block. Python Software Transactional Memory (PSTM) is an STM implementation in Python language. Its presentation fills a gap that Python lacks an applicable and reliable software transactional memory. PSTM satisfies the basic transaction properties, however it does not satisfy opacity, which defines conditions for serialising concurrent transaction. To alleviate this issue, we modify the PSTM implementation and present a new PSTM called PSTM-M. Based on PSTM-M, we verify opacity of this implementation. We present the formalization of opacity which is based on the history model of transaction. Further, we explain why PSTM does not satisfy opacity and present a modified PSTM called PSTM-M. Finally, we give a machine-checked proof for the opacity of PSTM-M based on the theorem prover Coq.
{"title":"Verifying Opacity of a Modified PSTM","authors":"Yucheng Fang, Huibiao Zhu, Jiaqi Yin","doi":"10.1109/TASE.2019.00008","DOIUrl":"https://doi.org/10.1109/TASE.2019.00008","url":null,"abstract":"Software transactional memory (STM) provides programmers with a high-level programming abstraction for synchronization of parallel processes, allowing blocks of codes that execute in an interleaved manner to be treated as an atomic block. Python Software Transactional Memory (PSTM) is an STM implementation in Python language. Its presentation fills a gap that Python lacks an applicable and reliable software transactional memory. PSTM satisfies the basic transaction properties, however it does not satisfy opacity, which defines conditions for serialising concurrent transaction. To alleviate this issue, we modify the PSTM implementation and present a new PSTM called PSTM-M. Based on PSTM-M, we verify opacity of this implementation. We present the formalization of opacity which is based on the history model of transaction. Further, we explain why PSTM does not satisfy opacity and present a modified PSTM called PSTM-M. Finally, we give a machine-checked proof for the opacity of PSTM-M based on the theorem prover Coq.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127518165","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}
Yi Xu, Weimin Ge, Xiaohong Li, Zhiyong Feng, Xiaofei Xie, Yude Bai
To guarantee the quality of software, specifying security requirements (SRs) is essential for developing systems, especially for security-critical software systems. However, using security threat to determine detailed SR is quite difficult according to Common Criteria (CC), which is too confusing and technical for non-security specialists. In this paper, we propose a Co-occurrence Recommend Model (CoRM) to automatically recommend software SRs. In this model, the security threats of product are extracted from security target documents of software, in which the related security requirements are tagged. In order to establish relationships between software security threat and security requirement, semantic similarities between different security threat is calculated by Skip-thoughts Model. To evaluate our CoRM model, over 1000 security target documents of 9 types software products are exploited. The results suggest that building a CoRM model via semantic similarity is feasible and reliable.
{"title":"A Co-Occurrence Recommendation Model of Software Security Requirement","authors":"Yi Xu, Weimin Ge, Xiaohong Li, Zhiyong Feng, Xiaofei Xie, Yude Bai","doi":"10.1109/TASE.2019.00-21","DOIUrl":"https://doi.org/10.1109/TASE.2019.00-21","url":null,"abstract":"To guarantee the quality of software, specifying security requirements (SRs) is essential for developing systems, especially for security-critical software systems. However, using security threat to determine detailed SR is quite difficult according to Common Criteria (CC), which is too confusing and technical for non-security specialists. In this paper, we propose a Co-occurrence Recommend Model (CoRM) to automatically recommend software SRs. In this model, the security threats of product are extracted from security target documents of software, in which the related security requirements are tagged. In order to establish relationships between software security threat and security requirement, semantic similarities between different security threat is calculated by Skip-thoughts Model. To evaluate our CoRM model, over 1000 security target documents of 9 types software products are exploited. The results suggest that building a CoRM model via semantic similarity is feasible and reliable.","PeriodicalId":183749,"journal":{"name":"2019 International Symposium on Theoretical Aspects of Software Engineering (TASE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127538499","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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