Pub Date : 1998-10-31DOI: 10.1109/DASC.1998.741500
C. Heitmeyer
A controversial issue in the formal methods research community is the degree to which mathematical sophistication and theorem proving skills should be needed to apply a formal method. A premise of this paper is that formal methods research has produced several techniques with potential utility in practical software development, but that mathematical sophistication and theorem proving skills should not be prerequisites for using these techniques. In the paper, several attributes needed to make a formal method useful in practice are described. These attributes include user-friendly notation, automated (i.e., push-button) analysis, and easy to understand feedback. To illustrate the attributes of a practical formal method, a formal method for requirements specification called SCR (Software Cost Reduction) is introduced.
{"title":"SCR: a practical method for requirements specification","authors":"C. Heitmeyer","doi":"10.1109/DASC.1998.741500","DOIUrl":"https://doi.org/10.1109/DASC.1998.741500","url":null,"abstract":"A controversial issue in the formal methods research community is the degree to which mathematical sophistication and theorem proving skills should be needed to apply a formal method. A premise of this paper is that formal methods research has produced several techniques with potential utility in practical software development, but that mathematical sophistication and theorem proving skills should not be prerequisites for using these techniques. In the paper, several attributes needed to make a formal method useful in practice are described. These attributes include user-friendly notation, automated (i.e., push-button) analysis, and easy to understand feedback. To illustrate the attributes of a practical formal method, a formal method for requirements specification called SCR (Software Cost Reduction) is introduced.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130858559","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 : 1998-10-31DOI: 10.1109/DASC.1998.741450
H. Negele, Ernst Fricke, Stefan Wenzel
To be successful in a highly dynamic environment, with increased global competition, shorter life cycles, more demanding customers/users, and more complex products, different industries should take advantage of learning from each other's problems and solutions. On the other hand, commercial companies can learn from aerospace industries' traditional strengths, in the areas of requirements engineering, modeling and simulation, or systems engineering. A variety of potential synergies exists that should be exploited to the greatest possible extent. But what method or tool should we use, and when? For an effective application of methods and tools in product development, a comprehensive framework is needed, which supports the selection, coordination, and assessment according to domain- and company-specific needs and constraints. Unfortunately, tools and methods often are used because it is popular to use them, but not because they ideally support the solution of specific problems. Therefore, in this paper a systematic approach is proposed on how methods and tools can be selected for a successful product development system, independent of the industrial sector of a company, but dependent on its problems, market constraints, and declared goals. A structured model, the House of CE+ (CE+ means concurrent engineering and more), was derived from the analysis of different product development processes at commercial companies in Germany, England, and the US (Wenzel & Bauch 1996). In the House of CE+, the interdependencies and relations between goals and problems, essentials/processes, and practices can be structured.
{"title":"The House of CE+-a systematic framework for selecting the \"right\" practices","authors":"H. Negele, Ernst Fricke, Stefan Wenzel","doi":"10.1109/DASC.1998.741450","DOIUrl":"https://doi.org/10.1109/DASC.1998.741450","url":null,"abstract":"To be successful in a highly dynamic environment, with increased global competition, shorter life cycles, more demanding customers/users, and more complex products, different industries should take advantage of learning from each other's problems and solutions. On the other hand, commercial companies can learn from aerospace industries' traditional strengths, in the areas of requirements engineering, modeling and simulation, or systems engineering. A variety of potential synergies exists that should be exploited to the greatest possible extent. But what method or tool should we use, and when? For an effective application of methods and tools in product development, a comprehensive framework is needed, which supports the selection, coordination, and assessment according to domain- and company-specific needs and constraints. Unfortunately, tools and methods often are used because it is popular to use them, but not because they ideally support the solution of specific problems. Therefore, in this paper a systematic approach is proposed on how methods and tools can be selected for a successful product development system, independent of the industrial sector of a company, but dependent on its problems, market constraints, and declared goals. A structured model, the House of CE+ (CE+ means concurrent engineering and more), was derived from the analysis of different product development processes at commercial companies in Germany, England, and the US (Wenzel & Bauch 1996). In the House of CE+, the interdependencies and relations between goals and problems, essentials/processes, and practices can be structured.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128704313","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 : 1998-10-31DOI: 10.1109/DASC.1998.739852
R. Black
As hardware development techniques have improved, the time to market in avionics systems has become increasingly dependent upon systems analysis and software development. At the same time the lion's share of life cycle costs have migrated from development to integration and maintenance. In order to remain competitive in today's government and private sectors, avionics system developers must employ a scheme which reduces systems analysis, software development, and overall integration efforts. Such a scheme includes an effective process, a flexible architecture, and the tools necessary to greatly reduce life cycle costs. This paper presents a spiral development process with an associated architecture and tool template designed to reduce time to market. Specific uses of this template on the International Space Station and the Boeing 777 avionics system are described along with the next generation implementation.
{"title":"Rapid development of avionics systems","authors":"R. Black","doi":"10.1109/DASC.1998.739852","DOIUrl":"https://doi.org/10.1109/DASC.1998.739852","url":null,"abstract":"As hardware development techniques have improved, the time to market in avionics systems has become increasingly dependent upon systems analysis and software development. At the same time the lion's share of life cycle costs have migrated from development to integration and maintenance. In order to remain competitive in today's government and private sectors, avionics system developers must employ a scheme which reduces systems analysis, software development, and overall integration efforts. Such a scheme includes an effective process, a flexible architecture, and the tools necessary to greatly reduce life cycle costs. This paper presents a spiral development process with an associated architecture and tool template designed to reduce time to market. Specific uses of this template on the International Space Station and the Boeing 777 avionics system are described along with the next generation implementation.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122657987","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 : 1998-10-31DOI: 10.1109/DASC.1998.739888
M.S. Gaudeski
This paper defines the next generation of the proof-of-concept Multimedia Analysis and Archive System (MAAS-2) with the initial installation being in the Joint Analysis Center at Molesworth, England in support of the Bosnia peace keeping effort. The paper describes the operational scenarios in use today at one of the premier European sites and the progression the proof-of-concept video analyst systems NTA and GD-IS have made and are proposing to make. The most sophisticated site/user of the UAV Bosnia mission video data is the Multinational Intelligence Coordination Cell, MICC, at the Joint Analysis Center, JAC, Molesworth England. This site was dominated by manual processes that require the analyst to focus on VHS video productions and editing techniques.
{"title":"Multimedia Analysis and Archive System (MAAS) for Joint Analysis Center (JAC) Molesworth, England in support of the Bosnia peace-keeping mission","authors":"M.S. Gaudeski","doi":"10.1109/DASC.1998.739888","DOIUrl":"https://doi.org/10.1109/DASC.1998.739888","url":null,"abstract":"This paper defines the next generation of the proof-of-concept Multimedia Analysis and Archive System (MAAS-2) with the initial installation being in the Joint Analysis Center at Molesworth, England in support of the Bosnia peace keeping effort. The paper describes the operational scenarios in use today at one of the premier European sites and the progression the proof-of-concept video analyst systems NTA and GD-IS have made and are proposing to make. The most sophisticated site/user of the UAV Bosnia mission video data is the Multinational Intelligence Coordination Cell, MICC, at the Joint Analysis Center, JAC, Molesworth England. This site was dominated by manual processes that require the analyst to focus on VHS video productions and editing techniques.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"46 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120978612","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 : 1998-10-31DOI: 10.1109/DASC.1998.741550
A. Helfrick, A. Wilson
The problem of interference from portable electronic devices, PEDs, to avionics systems has been known for more than 30 years. This problem has been periodically studied but other than identifying the airlines as the responsible party for policing the situation, no hardware has ever been designed to combat the problem. The latest report on the subject from the RTCA, DO-233 suggested a hardware detection system as a possible safeguard against future problems. This paper describes the preliminary design of such a detection system.
{"title":"Investigations into a system for the detection and location of potentially harmful radiation from portable electronics carried onboard aircraft","authors":"A. Helfrick, A. Wilson","doi":"10.1109/DASC.1998.741550","DOIUrl":"https://doi.org/10.1109/DASC.1998.741550","url":null,"abstract":"The problem of interference from portable electronic devices, PEDs, to avionics systems has been known for more than 30 years. This problem has been periodically studied but other than identifying the airlines as the responsible party for policing the situation, no hardware has ever been designed to combat the problem. The latest report on the subject from the RTCA, DO-233 suggested a hardware detection system as a possible safeguard against future problems. This paper describes the preliminary design of such a detection system.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"04 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127169487","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 : 1998-10-31DOI: 10.1109/DASC.1998.741559
A. Dillard
The increased speed with which new technologies are being introduced into the modern aviation operating environment has made it necessary to find new ways of evaluating certification, human factors, operational and safety issues. We no longer have the luxury of an extended development program, followed by an evolutionary period of products maturing into more complex forms, with an extended useful life. Modern technology delivers fully formed products to the marketplace with rapid wide distribution and, in many cases, a limited operating life due to forced obsolescence caused by new advances and technologies. Aviation has always been a technology leader, and this hasn't changed, so the introduction of new communication, navigation, surveillance and display technology is moving forward at a fast pace. Aviation is also a very competitive business, and maximum benefit comes from the early implementation of innovative new products and applications. While some time elements of the product life cycle have changed, critical requirements for validating safety, reliability and system integrity in civil aviation have not. The process of operationally integrating a new technology into an existing, highly complex, costly and potentially hazardous domain, such as airports and aircraft cockpits, demands an exhaustive evaluation of their effects on the existing system, while maintaining safety and performance standards, support logistics and affordability. To shorten the time required for equipment and procedural development, and operational implementation, the use of simulation has grown in importance. Simulation can consist of virtual modeling on a computer workstation, part task devices with actual system hardware and software, or full-mission man-in-the-loop simulators with visual systems and motion. All have their place in the process, and all play a role in shortening development time and cost. We will be looking at the use of full-mission simulators for piloted operational evaluations.
{"title":"Real-time operational evaluations using advanced flight simulators","authors":"A. Dillard","doi":"10.1109/DASC.1998.741559","DOIUrl":"https://doi.org/10.1109/DASC.1998.741559","url":null,"abstract":"The increased speed with which new technologies are being introduced into the modern aviation operating environment has made it necessary to find new ways of evaluating certification, human factors, operational and safety issues. We no longer have the luxury of an extended development program, followed by an evolutionary period of products maturing into more complex forms, with an extended useful life. Modern technology delivers fully formed products to the marketplace with rapid wide distribution and, in many cases, a limited operating life due to forced obsolescence caused by new advances and technologies. Aviation has always been a technology leader, and this hasn't changed, so the introduction of new communication, navigation, surveillance and display technology is moving forward at a fast pace. Aviation is also a very competitive business, and maximum benefit comes from the early implementation of innovative new products and applications. While some time elements of the product life cycle have changed, critical requirements for validating safety, reliability and system integrity in civil aviation have not. The process of operationally integrating a new technology into an existing, highly complex, costly and potentially hazardous domain, such as airports and aircraft cockpits, demands an exhaustive evaluation of their effects on the existing system, while maintaining safety and performance standards, support logistics and affordability. To shorten the time required for equipment and procedural development, and operational implementation, the use of simulation has grown in importance. Simulation can consist of virtual modeling on a computer workstation, part task devices with actual system hardware and software, or full-mission man-in-the-loop simulators with visual systems and motion. All have their place in the process, and all play a role in shortening development time and cost. We will be looking at the use of full-mission simulators for piloted operational evaluations.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129118065","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 : 1998-10-31DOI: 10.1109/DASC.1998.741454
M. Broy, P. Scholz
Today, more and more electronic parts of automobiles or aircrafts are realized as software, often distributed on a network of high-performance processors that are embedded in the car or airplane. In the systematic development of a distributed interactive system, we distinguish the following views: the interface view, the data view, the distribution view, and the process view. Each of these views is helpful and has its place in the development and design process of systems. We show how to formalize these different views by logical means. The development of a system is carried through several levels of abstraction. We also demonstrate how to formalize the typical steps in the development process. In particular we may identify three directions of development: refinement within one level of abstraction transition from one level of abstraction to another incremental development by enlarging the functionality. We introduce refinement relations to capture these three dimensions of the development space. We give verification conditions for these refinement steps. In this way, a logical basis for the development of systems is created.
{"title":"Systems engineering needs a formal basis","authors":"M. Broy, P. Scholz","doi":"10.1109/DASC.1998.741454","DOIUrl":"https://doi.org/10.1109/DASC.1998.741454","url":null,"abstract":"Today, more and more electronic parts of automobiles or aircrafts are realized as software, often distributed on a network of high-performance processors that are embedded in the car or airplane. In the systematic development of a distributed interactive system, we distinguish the following views: the interface view, the data view, the distribution view, and the process view. Each of these views is helpful and has its place in the development and design process of systems. We show how to formalize these different views by logical means. The development of a system is carried through several levels of abstraction. We also demonstrate how to formalize the typical steps in the development process. In particular we may identify three directions of development: refinement within one level of abstraction transition from one level of abstraction to another incremental development by enlarging the functionality. We introduce refinement relations to capture these three dimensions of the development space. We give verification conditions for these refinement steps. In this way, a logical basis for the development of systems is created.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114938916","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 : 1998-10-31DOI: 10.1109/DASC.1998.739834
P.J. Smith, C. Billings, D. Woods, C. McCoy
Air carriers have indicated a need for a less constrained, more flexible air traffic management (ATM) system. In response to this need, RTCA (1995) advanced proposals for a "free flight" system in which the airlines will be able to pursue their objectives more efficiently. The RTCA proposal assumes a higher level of automation to assist air traffic service providers to detect and resolve short-term tactical conflicts, reducing the need to impose strategic constraints on the airspace system, It also implies that human operator roles and responsibilities in the future system may be markedly different from those in today's air traffic management system.
{"title":"Human factors issues in a future air traffic management system","authors":"P.J. Smith, C. Billings, D. Woods, C. McCoy","doi":"10.1109/DASC.1998.739834","DOIUrl":"https://doi.org/10.1109/DASC.1998.739834","url":null,"abstract":"Air carriers have indicated a need for a less constrained, more flexible air traffic management (ATM) system. In response to this need, RTCA (1995) advanced proposals for a \"free flight\" system in which the airlines will be able to pursue their objectives more efficiently. The RTCA proposal assumes a higher level of automation to assist air traffic service providers to detect and resolve short-term tactical conflicts, reducing the need to impose strategic constraints on the airspace system, It also implies that human operator roles and responsibilities in the future system may be markedly different from those in today's air traffic management system.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133988492","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 : 1998-10-31DOI: 10.1109/DASC.1998.739848
G. W. Mitschang
Much excellent work has been sponsored in further defining open system approaches for the next generation of systems. However, putting open system design into practice when one deals with legacy systems and interface, form/fit, and performance requirements is a significant challenge. Add to this, a typical company's own internal processes for system, hardware, and software design, which typically are aimed at optimizing single function performance, and the challenge is increased. For the future programmable CNI systems' market, this paper examines some of these issues, identifies additional business considerations that come into play and briefly describes work underway at GEC Marconi Hazeltine.
{"title":"Open system design for communications navigation and identification (CNI) avionics","authors":"G. W. Mitschang","doi":"10.1109/DASC.1998.739848","DOIUrl":"https://doi.org/10.1109/DASC.1998.739848","url":null,"abstract":"Much excellent work has been sponsored in further defining open system approaches for the next generation of systems. However, putting open system design into practice when one deals with legacy systems and interface, form/fit, and performance requirements is a significant challenge. Add to this, a typical company's own internal processes for system, hardware, and software design, which typically are aimed at optimizing single function performance, and the challenge is increased. For the future programmable CNI systems' market, this paper examines some of these issues, identifies additional business considerations that come into play and briefly describes work underway at GEC Marconi Hazeltine.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133603700","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 : 1998-10-31DOI: 10.1109/DASC.1998.739865
M. Fodor, J. Yester, D. Hrovat
The overview presented here only begins to address some of the basic design aspects of three systems which are either commonly available as products or have been extensively researched. The depth of design considerations in this field is considerable. As each of these considerations is mastered by the engineering community, vehicle dynamic controls will continue to deliver safer, more pleasing products to consumers at greater value. Ultimately, the influence of these systems on automobiles will approach the influence that aircraft controls have had in their industry. Active control of vehicle dynamics has become a rich field of study and innovation for the automotive industry and will become increasingly more critical to the marketability of automotive products in the future.
{"title":"Active control of vehicle dynamics","authors":"M. Fodor, J. Yester, D. Hrovat","doi":"10.1109/DASC.1998.739865","DOIUrl":"https://doi.org/10.1109/DASC.1998.739865","url":null,"abstract":"The overview presented here only begins to address some of the basic design aspects of three systems which are either commonly available as products or have been extensively researched. The depth of design considerations in this field is considerable. As each of these considerations is mastered by the engineering community, vehicle dynamic controls will continue to deliver safer, more pleasing products to consumers at greater value. Ultimately, the influence of these systems on automobiles will approach the influence that aircraft controls have had in their industry. Active control of vehicle dynamics has become a rich field of study and innovation for the automotive industry and will become increasingly more critical to the marketability of automotive products in the future.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134190272","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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