Pub Date : 1998-10-31DOI: 10.1109/DASC.1998.741556
S. Chappell
If a system or procedure is being developed that will be used by humans, the design should be human-centered. Human-centered design capitalizes on and accommodates human skills in perception, attention, and cognition, while minimizing the opportunities for and effects of human error. This paper describes a mature practical process for accomplishing this goal of human-centered design. Usability is the foundation of this process. The first step in creating a human-centered system is to determine who the operators are, how, where, and what they are using the system for now, and what they would like to use it for in the future. The next step is to set relevant and realistic usability goals for the user interface of the new system. These goals include the time to accomplish the task and error tolerance. The final step is to perform usability testing, starting with a prototype. Many usability issues will become apparent by creating scenarios that 1) exercise a representative sample, if not all, of the operator functions and 2) provide a realistic operational environment for testing. By collecting and analyzing usability data, specific interface features can be evaluated and any mismatch between the design and the operational use will be revealed. Through iterative design improvements the final product will be easy to use and difficult to use incorrectly.
{"title":"Certification of usability: a process for creating a human-centered system","authors":"S. Chappell","doi":"10.1109/DASC.1998.741556","DOIUrl":"https://doi.org/10.1109/DASC.1998.741556","url":null,"abstract":"If a system or procedure is being developed that will be used by humans, the design should be human-centered. Human-centered design capitalizes on and accommodates human skills in perception, attention, and cognition, while minimizing the opportunities for and effects of human error. This paper describes a mature practical process for accomplishing this goal of human-centered design. Usability is the foundation of this process. The first step in creating a human-centered system is to determine who the operators are, how, where, and what they are using the system for now, and what they would like to use it for in the future. The next step is to set relevant and realistic usability goals for the user interface of the new system. These goals include the time to accomplish the task and error tolerance. The final step is to perform usability testing, starting with a prototype. Many usability issues will become apparent by creating scenarios that 1) exercise a representative sample, if not all, of the operator functions and 2) provide a realistic operational environment for testing. By collecting and analyzing usability data, specific interface features can be evaluated and any mismatch between the design and the operational use will be revealed. Through iterative design improvements the final product will be easy to use and difficult to use incorrectly.","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":"122689603","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.1998.741587
K. Williams
This paper is a review of human factors problems associated with the user-interface design of a set of Global Positioning System (GPS) receivers, certified for use in aircraft for instrument non-precision approaches. The paper focuses on design problems associated with the interfaces and specific inconsistencies across the set of interfaces that could cause confusion or errors during operation. Some specific problems to be addressed involve the layout and design of knobs and buttons; control labeling inconsistencies across units; the placement and use of warnings; feedback, or the lack thereof; and the integration of specific flying tasks while using the receivers. Recommendations for solving some of the problems are provided, as well as suggestions to the FAA, GPS manufacturers, and pilots regarding the future development and use of these products.
{"title":"GPS user-interface design problems","authors":"K. Williams","doi":"10.1109/DASC.1998.741587","DOIUrl":"https://doi.org/10.1109/DASC.1998.741587","url":null,"abstract":"This paper is a review of human factors problems associated with the user-interface design of a set of Global Positioning System (GPS) receivers, certified for use in aircraft for instrument non-precision approaches. The paper focuses on design problems associated with the interfaces and specific inconsistencies across the set of interfaces that could cause confusion or errors during operation. Some specific problems to be addressed involve the layout and design of knobs and buttons; control labeling inconsistencies across units; the placement and use of warnings; feedback, or the lack thereof; and the integration of specific flying tasks while using the receivers. Recommendations for solving some of the problems are provided, as well as suggestions to the FAA, GPS manufacturers, and pilots regarding the future development and use of these products.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"15 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":"131570526","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.1998.739865
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}
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.1998.741454
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.1998.741516
R. Hammett
Today's aircraft use ultra-reliable real-time controls for demanding functions such as Fly-By-Wire (FBW) flight control. Future aircraft, spacecraft and other vehicles will require greater use of these types of controls for functions that currently are allowed to fail, fail to degraded operation, or require human intervention in response to failure. Fully automated and autonomous functions will require ultra-reliable control. But ultra-reliable systems are very expensive to design and require large amounts of onboard equipment. This paper will discuss how the use of low-cost sensors with digital outputs, digitally commanded fault-tolerant actuation devices and interconnecting networks of low-cost data buses offer the promise of more affordable ultra-reliable systems. Specific technologies and concepts to be discussed include low-cost automotive and industrial data buses, "smart" actuation devices with integral fault masking capabilities, management of redundant sensors, and the fault detection and diagnosis of the data network. The advantages of integrating the control and distribution of electrical power with the control system will be illustrated. The design, installation, and upgrade flexibility benefits provided by an all-digital and shared network approach are presented. The economic benefits of systems that can operate following failure and without immediate repair will be reviewed. The inherent ability of these redundant systems to provide effective built-in-test and self-diagnostics capabilities will be described. The challenges associated with developing ultra-reliable software for these systems and the difficulties associated with exhaustive verification testing will be presented as will additional development hurdles that must be overcome.
{"title":"Ultra-reliable real-time control systems-future trends","authors":"R. Hammett","doi":"10.1109/DASC.1998.741516","DOIUrl":"https://doi.org/10.1109/DASC.1998.741516","url":null,"abstract":"Today's aircraft use ultra-reliable real-time controls for demanding functions such as Fly-By-Wire (FBW) flight control. Future aircraft, spacecraft and other vehicles will require greater use of these types of controls for functions that currently are allowed to fail, fail to degraded operation, or require human intervention in response to failure. Fully automated and autonomous functions will require ultra-reliable control. But ultra-reliable systems are very expensive to design and require large amounts of onboard equipment. This paper will discuss how the use of low-cost sensors with digital outputs, digitally commanded fault-tolerant actuation devices and interconnecting networks of low-cost data buses offer the promise of more affordable ultra-reliable systems. Specific technologies and concepts to be discussed include low-cost automotive and industrial data buses, \"smart\" actuation devices with integral fault masking capabilities, management of redundant sensors, and the fault detection and diagnosis of the data network. The advantages of integrating the control and distribution of electrical power with the control system will be illustrated. The design, installation, and upgrade flexibility benefits provided by an all-digital and shared network approach are presented. The economic benefits of systems that can operate following failure and without immediate repair will be reviewed. The inherent ability of these redundant systems to provide effective built-in-test and self-diagnostics capabilities will be described. The challenges associated with developing ultra-reliable software for these systems and the difficulties associated with exhaustive verification testing will be presented as will additional development hurdles that must be overcome.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"10 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":"115118065","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.1998.741441
C. J. Sitter, G. Provan
We present a flexible, powerful, easily maintainable avionics diagnostics system that integrates diagnostic development functions into product development tools and processes.
我们提出了一个灵活，强大，易于维护的航空电子诊断系统，将诊断开发功能集成到产品开发工具和流程中。
{"title":"Advanced maintenance using causal networks","authors":"C. J. Sitter, G. Provan","doi":"10.1109/DASC.1998.741441","DOIUrl":"https://doi.org/10.1109/DASC.1998.741441","url":null,"abstract":"We present a flexible, powerful, easily maintainable avionics diagnostics system that integrates diagnostic development functions into product development tools and processes.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"6 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":"115611539","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.1998.741498
J. Sutton
Avionics system development offers us a dilemma. You know how you'd like to develop systems...highest possible integrity, lowest failure rates, best ergonomics. You also know what will price you out of the market and abandon the business to your competitors: "bleeding edge" efforts to extract a theoretical last advantage from your product. What we really need is a "Club Med" experience on a survivable "Motel 6" budget.
{"title":"\"Club Med\"/sup TM/ avionics at \"Motel 6\"/sup TM/ costs: win/win development strategies","authors":"J. Sutton","doi":"10.1109/DASC.1998.741498","DOIUrl":"https://doi.org/10.1109/DASC.1998.741498","url":null,"abstract":"Avionics system development offers us a dilemma. You know how you'd like to develop systems...highest possible integrity, lowest failure rates, best ergonomics. You also know what will price you out of the market and abandon the business to your competitors: \"bleeding edge\" efforts to extract a theoretical last advantage from your product. What we really need is a \"Club Med\" experience on a survivable \"Motel 6\" budget.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"176 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":"115889565","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.1998.741553
M. Malekpour
The design and development of a closed-loop system to study and evaluate the performance of the Honeywell recoverable computer system (RCS) in electromagnetic environments (EME) is presented. The development of a Windows-based software package to handle the time critical communication of data and commands between the RCS and flight simulation code in real-time, while meeting the stringent hard deadlines is also presented. The performance results of the RCS while exercising flight control laws under ideal conditions as well as in the presence of electromagnetic fields is also discussed.
{"title":"Evaluation of Honeywell recoverable computer system (RCS) in presence of electromagnetic effects","authors":"M. Malekpour","doi":"10.1109/DASC.1998.741553","DOIUrl":"https://doi.org/10.1109/DASC.1998.741553","url":null,"abstract":"The design and development of a closed-loop system to study and evaluate the performance of the Honeywell recoverable computer system (RCS) in electromagnetic environments (EME) is presented. The development of a Windows-based software package to handle the time critical communication of data and commands between the RCS and flight simulation code in real-time, while meeting the stringent hard deadlines is also presented. The performance results of the RCS while exercising flight control laws under ideal conditions as well as in the presence of electromagnetic fields is also discussed.","PeriodicalId":335827,"journal":{"name":"17th DASC. AIAA/IEEE/SAE. Digital Avionics Systems Conference. Proceedings (Cat. No.98CH36267)","volume":"37 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":"123344655","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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