Pub Date : 1990-10-31DOI: 10.1109/CMPSAC.1990.139429
R. V. Rubin, James Walker, E. Golin
The authors describe Visual Programmers Workbench (VPW), which addresses the rapid synthesis of programming environments for the specification, analysis, and execution of visual programs. A language-based environment for a specific visual language is generated in VPW from a specification of the syntactic structure, the abstract structure, the static semantics, and the dynamic semantics of the language. VPW is built around a model of distributed processing based on shared distributed memory. This framework is used both for defining the architecture of the environment and for the execution model of programming languages. The VPW has been used to experiment with visual programming environments for several visual languages. The design of the Visual Programmers Workbench and experience with using it to generate a distributed programming environment for a concurrent visual language are described.<>
{"title":"Design and implementation of programming environments in the Visual Programmers Workbench","authors":"R. V. Rubin, James Walker, E. Golin","doi":"10.1109/CMPSAC.1990.139429","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139429","url":null,"abstract":"The authors describe Visual Programmers Workbench (VPW), which addresses the rapid synthesis of programming environments for the specification, analysis, and execution of visual programs. A language-based environment for a specific visual language is generated in VPW from a specification of the syntactic structure, the abstract structure, the static semantics, and the dynamic semantics of the language. VPW is built around a model of distributed processing based on shared distributed memory. This framework is used both for defining the architecture of the environment and for the execution model of programming languages. The VPW has been used to experiment with visual programming environments for several visual languages. The design of the Visual Programmers Workbench and experience with using it to generate a distributed programming environment for a concurrent visual language are described.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124317559","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139373
Angelo J. Incorvaia, A. Davis, R. Fairley
The authors present the results of six case studies of software reuse performed in five organizations: Digital Equipment Corporation (DEC), BTG Inc., the US Army, Raytheon Company and Hartford Insurance. The authors' objectives are to (1) report on reuse efforts currently under way and (2) identify recurring factors among these efforts. Perhaps the most important observation made by the authors is that there is no right or wrong way to practice software reuse. In some organizations, a more formal approach is appropriate, while in others less formal approaches work. It seems more important to find an approach that fits the culture than to follow some textbook method. Eighteen hypotheses concerning reuse efforts are formulated on the basis of these observations.<>
{"title":"Case studies in software reuse","authors":"Angelo J. Incorvaia, A. Davis, R. Fairley","doi":"10.1109/CMPSAC.1990.139373","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139373","url":null,"abstract":"The authors present the results of six case studies of software reuse performed in five organizations: Digital Equipment Corporation (DEC), BTG Inc., the US Army, Raytheon Company and Hartford Insurance. The authors' objectives are to (1) report on reuse efforts currently under way and (2) identify recurring factors among these efforts. Perhaps the most important observation made by the authors is that there is no right or wrong way to practice software reuse. In some organizations, a more formal approach is appropriate, while in others less formal approaches work. It seems more important to find an approach that fits the culture than to follow some textbook method. Eighteen hypotheses concerning reuse efforts are formulated on the basis of these observations.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124564249","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139343
V. Sembugamoorthy, L. Brothers
Attention is given to ICICLE (intelligent code inspection in a C language environment), an intelligent assistant that augments manual code inspection by providing a rule-based static-debugging tool, hypertext-based browsers for referring to various kinds of knowledge associated with code inspection (e.g., the application domain knowledge and the knowledge of the programming environment), a powerful human interface for preparing comments on the code under inspection, and a CSCW (computer-supported cooperative work) platform for conducting code inspection meetings. ICICLE has been prototyped on UNIX workstations using a commercial multi-paradigm expert system shell and a window package for implementing CSCW. The initial prototype has been significantly enhanced based on the feedback from extensive videotaped usability testing sessions which used a real-world application. It is currently being used for live code inspection by an initial user organization. The goals, the approach, the architecture, the main components, the usability testing, and the future directions of ICICLE are described.<>
{"title":"ICICLE: Intelligent code inspection in a C language environment","authors":"V. Sembugamoorthy, L. Brothers","doi":"10.1109/CMPSAC.1990.139343","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139343","url":null,"abstract":"Attention is given to ICICLE (intelligent code inspection in a C language environment), an intelligent assistant that augments manual code inspection by providing a rule-based static-debugging tool, hypertext-based browsers for referring to various kinds of knowledge associated with code inspection (e.g., the application domain knowledge and the knowledge of the programming environment), a powerful human interface for preparing comments on the code under inspection, and a CSCW (computer-supported cooperative work) platform for conducting code inspection meetings. ICICLE has been prototyped on UNIX workstations using a commercial multi-paradigm expert system shell and a window package for implementing CSCW. The initial prototype has been significantly enhanced based on the feedback from extensive videotaped usability testing sessions which used a real-world application. It is currently being used for live code inspection by an initial user organization. The goals, the approach, the architecture, the main components, the usability testing, and the future directions of ICICLE are described.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114680699","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139342
S. Ramanna, J. Peters, E. A. Unger, K. W. Glander
The authors report on the design of a dynamic integrity constraint checker with a nonmonotonic interval logic (IL). Central to this logic is the inclusion of the unless operator which captures the nonmonotonicity of dynamic integrity constraints over temporal intervals. IL is embedded in the Ada/ISL Interval Specification Language which has been utilized in the design of the Icarus Integrity System. In this system, the answer to a query depends on the availability of an explicit body of knowledge (knowledge base) about the integrity of data items contained in the query. The principal inference mechanism in this system is the refutation of faulty beliefs about data based on partial information and intuition, with respect to facts in the knowledge base. A technique for the verification of the Icarus kernel is presented. A family of assertions about the completeness, correctness, and confidence integrity characteristics about data is included in the integrity model.<>
{"title":"Designing a dynamic integrity constraint checker with nonmonotonic logic","authors":"S. Ramanna, J. Peters, E. A. Unger, K. W. Glander","doi":"10.1109/CMPSAC.1990.139342","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139342","url":null,"abstract":"The authors report on the design of a dynamic integrity constraint checker with a nonmonotonic interval logic (IL). Central to this logic is the inclusion of the unless operator which captures the nonmonotonicity of dynamic integrity constraints over temporal intervals. IL is embedded in the Ada/ISL Interval Specification Language which has been utilized in the design of the Icarus Integrity System. In this system, the answer to a query depends on the availability of an explicit body of knowledge (knowledge base) about the integrity of data items contained in the query. The principal inference mechanism in this system is the refutation of faulty beliefs about data based on partial information and intuition, with respect to facts in the knowledge base. A technique for the verification of the Icarus kernel is presented. A family of assertions about the completeness, correctness, and confidence integrity characteristics about data is included in the integrity model.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123947852","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139426
S. Upadhyaya
Rollback recovery is a backward error recovery technique for recovering from transient faults in computing systems. Real-time systems employing fault tolerance and reconfiguration generally have time-dependent (dynamic) constraints. The author presents a novel rollback point insertion strategy which evaluates the rollback conditions on-line. The technique minimizes both time and space overhead associated with rollback, thereby making it applicable to real-time systems with dynamic constraints. The algorithm presented attains a near-optimum solution in terms of the time spent in saving the states of the system. Details of the simulation conducted to validate the technique are also given. The simulation study has established that the degradation in performance due to using the proposed algorithms is insignificant and the precomputation time is very small for programs that can be represented by general acyclic graphs. On the other hand, for structured programs that can be represented by a simple sequence of tasks, the computation overhead is almost zero.<>
{"title":"Rollback recovery in real-time systems with dynamic constraints","authors":"S. Upadhyaya","doi":"10.1109/CMPSAC.1990.139426","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139426","url":null,"abstract":"Rollback recovery is a backward error recovery technique for recovering from transient faults in computing systems. Real-time systems employing fault tolerance and reconfiguration generally have time-dependent (dynamic) constraints. The author presents a novel rollback point insertion strategy which evaluates the rollback conditions on-line. The technique minimizes both time and space overhead associated with rollback, thereby making it applicable to real-time systems with dynamic constraints. The algorithm presented attains a near-optimum solution in terms of the time spent in saving the states of the system. Details of the simulation conducted to validate the technique are also given. The simulation study has established that the degradation in performance due to using the proposed algorithms is insignificant and the precomputation time is very small for programs that can be represented by general acyclic graphs. On the other hand, for structured programs that can be represented by a simple sequence of tasks, the computation overhead is almost zero.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125970865","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139406
A. Ghafoor, I. Ahmad
The authors propose a distributed task scheduling model using a simple processor architecture and a heuristic scheduling algorithm based on small message exchanges between nearest neighbors. An extensive simulation study was used to analyze the proposed model by taking into account a wide range of practical issues. Comparison with other schemes reported in the literature reveals the superiority of the proposed model in terms of various performance measures. The scheduling algorithm supported by some software components improves the response time to a great extent by trying to keep the network nodes equally busy. The exchange of load status information has low complexity. An interesting trade-off between periodic update and non-periodic information update is exhibited. The performance of the proposed algorithms does not degrade when no transfer limit is used. The communication rate of the network has a major influence on the performance but it is shown that further reduction in response time cannot be achieved after a certain increase in communication rate. Simulation experiments on various network topologies showed the adaptive nature of the proposed algorithms.<>
{"title":"An efficient model of dynamic task scheduling for distributed systems","authors":"A. Ghafoor, I. Ahmad","doi":"10.1109/CMPSAC.1990.139406","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139406","url":null,"abstract":"The authors propose a distributed task scheduling model using a simple processor architecture and a heuristic scheduling algorithm based on small message exchanges between nearest neighbors. An extensive simulation study was used to analyze the proposed model by taking into account a wide range of practical issues. Comparison with other schemes reported in the literature reveals the superiority of the proposed model in terms of various performance measures. The scheduling algorithm supported by some software components improves the response time to a great extent by trying to keep the network nodes equally busy. The exchange of load status information has low complexity. An interesting trade-off between periodic update and non-periodic information update is exhibited. The performance of the proposed algorithms does not degrade when no transfer limit is used. The communication rate of the network has a major influence on the performance but it is shown that further reduction in response time cannot be achieved after a certain increase in communication rate. Simulation experiments on various network topologies showed the adaptive nature of the proposed algorithms.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129875250","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139404
H. Wedde, B. Korel, W. G. Brown, Shengdong Chen
The authors describe the file management system of DRAGON SLAYER, a distributed operating system which provides transparent resource sharing in a heterogeneous local area network with completely decentralized control. Users are able to use any of the system files for which they have authorization, without regard to the individual characteristics of the computers on which the files reside or the physical locations of the users and files. In addition, files can be dynamically fragmented, and the fragments can be replicated and relocated dynamically. Copies are kept mutually consistent while all file operations work either transparently on the whole file or on specific fragments. The DRAGON SLAYER resource management supporting these file system operations is presented. Beyond the obvious advantages of file access reliability and flexibility, the authors present simulation results proving the superior performance of this file system as compared with conventional distributed file systems with non-fragmented files.<>
{"title":"Distributed management of replicated and partitioned files under DRAGON SLAYER","authors":"H. Wedde, B. Korel, W. G. Brown, Shengdong Chen","doi":"10.1109/CMPSAC.1990.139404","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139404","url":null,"abstract":"The authors describe the file management system of DRAGON SLAYER, a distributed operating system which provides transparent resource sharing in a heterogeneous local area network with completely decentralized control. Users are able to use any of the system files for which they have authorization, without regard to the individual characteristics of the computers on which the files reside or the physical locations of the users and files. In addition, files can be dynamically fragmented, and the fragments can be replicated and relocated dynamically. Copies are kept mutually consistent while all file operations work either transparently on the whole file or on specific fragments. The DRAGON SLAYER resource management supporting these file system operations is presented. Beyond the obvious advantages of file access reliability and flexibility, the authors present simulation results proving the superior performance of this file system as compared with conventional distributed file systems with non-fragmented files.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"600 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132056820","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139423
J. Tsai, K. Fang, Yao-Dong Bi
Testing and debugging of real-time software systems are difficult because of timing constraints imposed on them and because of their nondeterministic behavior. Conventional static analysis is not adequate to deal with the violation of timing constraints which are inherent in real-time software systems. The authors present a dynamic analysis method which uses the recorded run-time information to test and debug this kind of timing error. Based on the proposed approach, a noninterference monitoring system architecture has been developed to collect the process-level and function-level program execution data of a target real-time software system without affecting its execution. Different-leveled logical views are then reconstructed from this collected run-time information. A dynamic analysis method is then presented to analyze the timing behavior of real-time software systems.<>
{"title":"On real-time software testing and debugging","authors":"J. Tsai, K. Fang, Yao-Dong Bi","doi":"10.1109/CMPSAC.1990.139423","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139423","url":null,"abstract":"Testing and debugging of real-time software systems are difficult because of timing constraints imposed on them and because of their nondeterministic behavior. Conventional static analysis is not adequate to deal with the violation of timing constraints which are inherent in real-time software systems. The authors present a dynamic analysis method which uses the recorded run-time information to test and debug this kind of timing error. Based on the proposed approach, a noninterference monitoring system architecture has been developed to collect the process-level and function-level program execution data of a target real-time software system without affecting its execution. Different-leveled logical views are then reconstructed from this collected run-time information. A dynamic analysis method is then presented to analyze the timing behavior of real-time software systems.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123744606","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139455
M. R. Basila, G. Stefanek, A. Çinar
A supervisory control expert system with object-based knowledge representation has been developed such that the general knowledge confined to classes and subclasses forms a core knowledge base which can be used as primitives for rapid prototyping of intelligent control systems for various chemical processes. The expert system is embedded in an application program and communicates with the control system structured in the form of control blocks. The expert system prototype is developed for retuning model-based controllers to improve the controlled behavior of a packed-bed chemical reactor system. The knowledge base of the model-object-based expert control system captures the complex structure and interdependencies of process control systems into a compact form that includes structure, declarative and heuristic relationships, and procedural and model based knowledge.<>
{"title":"A model-object based expert system for real-time intelligent control of chemical processes","authors":"M. R. Basila, G. Stefanek, A. Çinar","doi":"10.1109/CMPSAC.1990.139455","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139455","url":null,"abstract":"A supervisory control expert system with object-based knowledge representation has been developed such that the general knowledge confined to classes and subclasses forms a core knowledge base which can be used as primitives for rapid prototyping of intelligent control systems for various chemical processes. The expert system is embedded in an application program and communicates with the control system structured in the form of control blocks. The expert system prototype is developed for retuning model-based controllers to improve the controlled behavior of a packed-bed chemical reactor system. The knowledge base of the model-object-based expert control system captures the complex structure and interdependencies of process control systems into a compact form that includes structure, declarative and heuristic relationships, and procedural and model based knowledge.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122901649","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 : 1990-10-31DOI: 10.1109/CMPSAC.1990.139374
Kazuo Matsumura, Akihiro Yamashiro, Toshiyuki Tanaka, I. Takahashi
A technique to reuse standardized software components is presented which features a component development process and component-oriented object layers together with validity demonstrated through applications. The approach is called the 'standardized components and their composition approach.' The technique, on the condition that the architecture of a product family is fixed for a certain period of time, has the following features: (1) development of software components and that of software products are performed independently, and (2) guidelines for software component analysis/design can be obtained using an object layer which is based on shared software resources (called objects). This software component development approach has been applied to three different cases: process monitoring and control software (mainly Fortran); distributed information processing system software (Cobol); and microcomputer embedded product control software (C and assembler). Excellent results have been obtained.<>
{"title":"Modeling of software reusable component approach and its case study","authors":"Kazuo Matsumura, Akihiro Yamashiro, Toshiyuki Tanaka, I. Takahashi","doi":"10.1109/CMPSAC.1990.139374","DOIUrl":"https://doi.org/10.1109/CMPSAC.1990.139374","url":null,"abstract":"A technique to reuse standardized software components is presented which features a component development process and component-oriented object layers together with validity demonstrated through applications. The approach is called the 'standardized components and their composition approach.' The technique, on the condition that the architecture of a product family is fixed for a certain period of time, has the following features: (1) development of software components and that of software products are performed independently, and (2) guidelines for software component analysis/design can be obtained using an object layer which is based on shared software resources (called objects). This software component development approach has been applied to three different cases: process monitoring and control software (mainly Fortran); distributed information processing system software (Cobol); and microcomputer embedded product control software (C and assembler). Excellent results have been obtained.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"208 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122932804","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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