Pub Date : 2010-09-12DOI: 10.1109/ICSM.2010.5609577
K. Prete, Napol Rachatasumrit, Nikita Sudan, Miryung Kim
Knowing which types of refactoring occurred between two program versions can help programmers better understand code changes. Our survey of refactoring identification techniques found that existing techniques cannot easily identify complex refactorings, such as an replace conditional with polymorphism refactoring, which consist of a set of atomic refactorings. This paper presents REF-FINDER that identifies complex refactorings between two program versions using a template-based refactoring reconstruction approach—REF-FINDER expresses each refactoring type in terms of template logic rules and uses a logic programming engine to infer concrete refactoring instances. It currently supports sixty three refactoring types from Fowler's catalog, showing the most comprehensive coverage among existing techniques. The evaluation using code examples from Fowler's catalog and open source project histories shows that REF-FINDER identifies refactorings with an overall precision of 0.79 and recall of 0.95.
{"title":"Template-based reconstruction of complex refactorings","authors":"K. Prete, Napol Rachatasumrit, Nikita Sudan, Miryung Kim","doi":"10.1109/ICSM.2010.5609577","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609577","url":null,"abstract":"Knowing which types of refactoring occurred between two program versions can help programmers better understand code changes. Our survey of refactoring identification techniques found that existing techniques cannot easily identify complex refactorings, such as an replace conditional with polymorphism refactoring, which consist of a set of atomic refactorings. This paper presents REF-FINDER that identifies complex refactorings between two program versions using a template-based refactoring reconstruction approach—REF-FINDER expresses each refactoring type in terms of template logic rules and uses a logic programming engine to infer concrete refactoring instances. It currently supports sixty three refactoring types from Fowler's catalog, showing the most comprehensive coverage among existing techniques. The evaluation using code examples from Fowler's catalog and open source project histories shows that REF-FINDER identifies refactorings with an overall precision of 0.79 and recall of 0.95.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116626384","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609560
Thanh H. D. Nguyen, Bram Adams, A. Hassan
Dependency network measures capture various facets of the dependencies among software modules. For example, betweenness centrality measures how much information flows through a module compared to the rest of the network. Prior studies have shown that these measures are good predictors of post-release failures. However, these studies did not explore the causes for such good performance and did not provide guidance for practitioners to avoid future bugs. In this paper, we closely examine the causes for such performance by replicating prior studies using data from the Eclipse project. Our study shows that a small subset of dependency network measures have a large impact on post-release failure, while other network measures have a very limited impact. We also analyze the benefit of bug prediction in reducing testing cost. Finally, we explore the practical implications of the important network measures.
{"title":"Studying the impact of dependency network measures on software quality","authors":"Thanh H. D. Nguyen, Bram Adams, A. Hassan","doi":"10.1109/ICSM.2010.5609560","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609560","url":null,"abstract":"Dependency network measures capture various facets of the dependencies among software modules. For example, betweenness centrality measures how much information flows through a module compared to the rest of the network. Prior studies have shown that these measures are good predictors of post-release failures. However, these studies did not explore the causes for such good performance and did not provide guidance for practitioners to avoid future bugs. In this paper, we closely examine the causes for such performance by replicating prior studies using data from the Eclipse project. Our study shows that a small subset of dependency network measures have a large impact on post-release failure, while other network measures have a very limited impact. We also analyze the benefit of bug prediction in reducing testing cost. Finally, we explore the practical implications of the important network measures.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125135188","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609665
B. Hummel, Elmar Jürgens, L. Heinemann, M. Conradt
Although numerous different clone detection approaches have been proposed to date, not a single one is both incremental and scalable to very large code bases. They thus cannot provide real-time cloning information for clone management of very large systems. We present a novel, index-based clone detection algorithm for type 1 and 2 clones that is both incremental and scalable. It enables a new generation of clone management tools that provide real-time cloning information for very large software. We report on several case studies that show both its suitability for real-time clone detection and its scalability: on 42 MLOC of Eclipse code, average time to retrieve all clones for a file was below 1 second; on 100 machines, detection of all clones in 73 MLOC was completed in 36 minutes.
{"title":"Index-based code clone detection: incremental, distributed, scalable","authors":"B. Hummel, Elmar Jürgens, L. Heinemann, M. Conradt","doi":"10.1109/ICSM.2010.5609665","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609665","url":null,"abstract":"Although numerous different clone detection approaches have been proposed to date, not a single one is both incremental and scalable to very large code bases. They thus cannot provide real-time cloning information for clone management of very large systems. We present a novel, index-based clone detection algorithm for type 1 and 2 clones that is both incremental and scalable. It enables a new generation of clone management tools that provide real-time cloning information for very large software. We report on several case studies that show both its suitability for real-time clone detection and its scalability: on 42 MLOC of Eclipse code, average time to retrieve all clones for a file was below 1 second; on 100 machines, detection of all clones in 73 MLOC was completed in 36 minutes.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133892427","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609715
A. Corazza, S. Martino, Valerio Maggio, G. Scanniello
Reusing software by copying and pasting is a common practice in software development. This phenomenon is widely known as code cloning. Problems with clones are mainly due to the need of managing each duplication, thus increasing the effort to maintain software systems. Clone detection approaches generally take into account either the syntactic structure (e.g., Abstract Syntax Tree) or lexical elements (e.g., the signature of a function). In this paper we propose an approach to detect code clones, based on syntactic information enriched by lexical elements. To this end, we have defined a Tree Kernel function to compare Abstract Syntax Trees. A preliminary investigation has been also conducted to assess the validity of the proposed approach.
{"title":"A Tree Kernel based approach for clone detection","authors":"A. Corazza, S. Martino, Valerio Maggio, G. Scanniello","doi":"10.1109/ICSM.2010.5609715","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609715","url":null,"abstract":"Reusing software by copying and pasting is a common practice in software development. This phenomenon is widely known as code cloning. Problems with clones are mainly due to the need of managing each duplication, thus increasing the effort to maintain software systems. Clone detection approaches generally take into account either the syntactic structure (e.g., Abstract Syntax Tree) or lexical elements (e.g., the signature of a function). In this paper we propose an approach to detect code clones, based on syntactic information enriched by lexical elements. To this end, we have defined a Tree Kernel function to compare Abstract Syntax Trees. A preliminary investigation has been also conducted to assess the validity of the proposed approach.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124950457","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609588
A. Rountev, Kevin Van Valkenburgh, Dacong Yan, P. Sadayappan
Many existing sequential components, libraries, and applications will need to be re-engineered for parallelism. This work proposes a dynamic analysis of sequential Java programs that helps a programmer to understand bottlenecks for parallelism. The analysis measures the parallelism available in the program by considering a hypothetical parallel execution in which the code within a method executes sequentially, but each caller will execute in parallel with its callees. A best-case scenario is assumed: every statement executes as early as possible, as long as all dependences from the sequential program are satisfied. The idealized speedup under this model is a measure of the method-level parallelism inherent in the program, independent of hardware and JVMs. The analysis employs bytecode instrumentation and an online algorithm which tracks the reads and writes of relevant memory locations during a run of the sequential program. If the best-case parallelism is low, this likely means that the program cannot be easily re-engineered into a scalable parallel version. In experiments with 26 Java programs, we observed this situation for most programs. This problem is sometimes due to programmer decisions that were perfectly reasonable for a sequential program but would be detrimental to the performance of any parallel version. To pinpoint such decisions, we propose an approach that employs the dynamic analysis to automatically find memory locations whose read and write operations decrease the available parallelism. In three case studies, we demonstrate how these bottlenecks can be identified and eliminated using the proposed approach.
{"title":"Understanding parallelism-inhibiting dependences in sequential Java programs","authors":"A. Rountev, Kevin Van Valkenburgh, Dacong Yan, P. Sadayappan","doi":"10.1109/ICSM.2010.5609588","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609588","url":null,"abstract":"Many existing sequential components, libraries, and applications will need to be re-engineered for parallelism. This work proposes a dynamic analysis of sequential Java programs that helps a programmer to understand bottlenecks for parallelism. The analysis measures the parallelism available in the program by considering a hypothetical parallel execution in which the code within a method executes sequentially, but each caller will execute in parallel with its callees. A best-case scenario is assumed: every statement executes as early as possible, as long as all dependences from the sequential program are satisfied. The idealized speedup under this model is a measure of the method-level parallelism inherent in the program, independent of hardware and JVMs. The analysis employs bytecode instrumentation and an online algorithm which tracks the reads and writes of relevant memory locations during a run of the sequential program. If the best-case parallelism is low, this likely means that the program cannot be easily re-engineered into a scalable parallel version. In experiments with 26 Java programs, we observed this situation for most programs. This problem is sometimes due to programmer decisions that were perfectly reasonable for a sequential program but would be detrimental to the performance of any parallel version. To pinpoint such decisions, we propose an approach that employs the dynamic analysis to automatically find memory locations whose read and write operations decrease the available parallelism. In three case studies, we demonstrate how these bottlenecks can be identified and eliminated using the proposed approach.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132603018","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609680
Maryam Hasan, Eleni Stroulia, Denilson Barbosa, Manar H. Alalfi
Software teams, as they communicate throughout the life-cycle of their projects, generate a substantial stream of textual data. Through emails and chats, developers discuss the requirements of their software system, they negotiate the distribution of tasks among them, and they make decisions about the system design, and the internal structure and functionalities of its code modules. The software research community has long recognized the importance and potential usefulness of such textual information. In this paper, we discuss our recent work on systematically analyzing several textual streams collected through our WikiDev2.0 tool. We use two different text-analysis methods to examine five different sources of textual data. We report on our experience using our method on analyzing the communications of a nine-member team over four months.
{"title":"Analyzing natural-language artifacts of the software process","authors":"Maryam Hasan, Eleni Stroulia, Denilson Barbosa, Manar H. Alalfi","doi":"10.1109/ICSM.2010.5609680","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609680","url":null,"abstract":"Software teams, as they communicate throughout the life-cycle of their projects, generate a substantial stream of textual data. Through emails and chats, developers discuss the requirements of their software system, they negotiate the distribution of tasks among them, and they make decisions about the system design, and the internal structure and functionalities of its code modules. The software research community has long recognized the importance and potential usefulness of such textual information. In this paper, we discuss our recent work on systematically analyzing several textual streams collected through our WikiDev2.0 tool. We use two different text-analysis methods to examine five different sources of textual data. We report on our experience using our method on analyzing the communications of a nine-member team over four months.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122225298","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609672
Lingming Zhang, Tao Xie, Lu Zhang, N. Tillmann, J. D. Halleux, Hong Mei
Mutation testing has been used to assess and improve the quality of test inputs. Generating test inputs to achieve high mutant-killing ratios is important in mutation testing. However, existing test-generation techniques do not provide effective support for killing mutants in mutation testing. In this paper, we propose a general test-generation approach, called PexMutator, for mutation testing using Dynamic Symbolic Execution (DSE), a recent effective test-generation technique. Based on a set of transformation rules, PexMutator transforms a program under test to an instrumented meta-program that contains mutant-killing constraints. Then PexMutator uses DSE to generate test inputs for the meta-program. The mutant-killing constraints introduced via instrumentation guide DSE to generate test inputs to kill mutants automatically. We have implemented our approach as an extension for Pex, an automatic structural testing tool developed at Microsoft Research. Our preliminary experimental study shows that our approach is able to strongly kill more than 80% of all the mutants for the five studied subjects. In addition, PexMutator is able to outperform Pex, a state-of-the-art test-generation tool, in terms of strong mutant killing while achieving the same block coverage.
{"title":"Test generation via Dynamic Symbolic Execution for mutation testing","authors":"Lingming Zhang, Tao Xie, Lu Zhang, N. Tillmann, J. D. Halleux, Hong Mei","doi":"10.1109/ICSM.2010.5609672","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609672","url":null,"abstract":"Mutation testing has been used to assess and improve the quality of test inputs. Generating test inputs to achieve high mutant-killing ratios is important in mutation testing. However, existing test-generation techniques do not provide effective support for killing mutants in mutation testing. In this paper, we propose a general test-generation approach, called PexMutator, for mutation testing using Dynamic Symbolic Execution (DSE), a recent effective test-generation technique. Based on a set of transformation rules, PexMutator transforms a program under test to an instrumented meta-program that contains mutant-killing constraints. Then PexMutator uses DSE to generate test inputs for the meta-program. The mutant-killing constraints introduced via instrumentation guide DSE to generate test inputs to kill mutants automatically. We have implemented our approach as an extension for Pex, an automatic structural testing tool developed at Microsoft Research. Our preliminary experimental study shows that our approach is able to strongly kill more than 80% of all the mutants for the five studied subjects. In addition, PexMutator is able to outperform Pex, a state-of-the-art test-generation tool, in terms of strong mutant killing while achieving the same block coverage.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116421623","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609719
M. Collard, Jonathan I. Maletic, Brian P. Robinson
An approach to automate adaptive maintenance changes on large-scale software systems is presented. This approach uses lightweight parsing and lightweight on-the-fly static analysis to support transformations that make corrections to source code in response to adaptive maintenance changes, such as platform changes. SrcML, an XML source code representation, is used and transformations can be performed using either XSLT or LINQ. A number of specific adaptive changes are presented, based on recent adaptive maintenance needs from products at ABB Inc. The transformations are described in detail and then demonstrated on a number of examples from the production systems. The results are compared with manual adaptive changes that were done by professional developers. The approach performed better than the manual changes, as it successfully transformed instances missed by the developers while not missing any instances itself. The work demonstrates that this lightweight approach is both efficient and accurate with an overall cost savings in development time and effort.
{"title":"A lightweight transformational approach to support large scale adaptive changes","authors":"M. Collard, Jonathan I. Maletic, Brian P. Robinson","doi":"10.1109/ICSM.2010.5609719","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609719","url":null,"abstract":"An approach to automate adaptive maintenance changes on large-scale software systems is presented. This approach uses lightweight parsing and lightweight on-the-fly static analysis to support transformations that make corrections to source code in response to adaptive maintenance changes, such as platform changes. SrcML, an XML source code representation, is used and transformations can be performed using either XSLT or LINQ. A number of specific adaptive changes are presented, based on recent adaptive maintenance needs from products at ABB Inc. The transformations are described in detail and then demonstrated on a number of examples from the production systems. The results are compared with manual adaptive changes that were done by professional developers. The approach performed better than the manual changes, as it successfully transformed instances missed by the developers while not missing any instances itself. The work demonstrates that this lightweight approach is both efficient and accurate with an overall cost savings in development time and effort.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115737898","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5609583
H. Sneed
This paper is an industrial report on a project for migrating an airport management system from a Bull mainframe using COBOL as a programming language and IDS as a database system to a distributed UNIX platform using Java and Oracle. The focus here is on the automated language transformation, performed in three phases - reengineering, conversion and refinement. The tools used are COBRedo for reengineering the COBOL code, COB2Java for converting COBOL to Java and JavRedoc for documenting the converted Java code. The paper describes the migration process and the tools used in it and the reviews the current state of the project. Keywords: Migration, Reengineering, Legacy systems, COBOL, Java, Object-oriented transformation.
{"title":"Migrating from COBOL to Java","authors":"H. Sneed","doi":"10.1109/ICSM.2010.5609583","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5609583","url":null,"abstract":"This paper is an industrial report on a project for migrating an airport management system from a Bull mainframe using COBOL as a programming language and IDS as a database system to a distributed UNIX platform using Java and Oracle. The focus here is on the automated language transformation, performed in three phases - reengineering, conversion and refinement. The tools used are COBRedo for reengineering the COBOL code, COB2Java for converting COBOL to Java and JavRedoc for documenting the converted Java code. The paper describes the migration process and the tools used in it and the reviews the current state of the project. Keywords: Migration, Reengineering, Legacy systems, COBOL, Java, Object-oriented transformation.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127339957","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 : 2010-09-12DOI: 10.1109/ICSM.2010.5610422
S. Tilley, T. Parveen
Regression testing is often performed as part of the software maintenance process. The amount of tests cases for a large-scale system can range from several hundred to many thousands, requiring significant computing resources and lengthy execution times, often precluding their use in an interactive setting. Traditional approaches to reduce the execution time for regression testing typically focus on excluding selected tests from the suite that need to be run after a change is made to the system.
{"title":"Migrating software testing to the cloud","authors":"S. Tilley, T. Parveen","doi":"10.1109/ICSM.2010.5610422","DOIUrl":"https://doi.org/10.1109/ICSM.2010.5610422","url":null,"abstract":"Regression testing is often performed as part of the software maintenance process. The amount of tests cases for a large-scale system can range from several hundred to many thousands, requiring significant computing resources and lengthy execution times, often precluding their use in an interactive setting. Traditional approaches to reduce the execution time for regression testing typically focus on excluding selected tests from the suite that need to be run after a change is made to the system.","PeriodicalId":101801,"journal":{"name":"2010 IEEE International Conference on Software Maintenance","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132455082","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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