Pub Date : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218390
S. Dorfman, J. Daily, T. Gonzalez, G. Kondo
Low altitude level flight segments increase fuel burn and emissions for the aircraft flying them. The number and length of level segments flown during arrival and departure operations can be reduced by procedure design which leverages the advantages of Area Navigation (RNAV) to reduce actual level flight. Such design must take into account many factors including terrain, current route of a particular flow of air traffic, other proximate air traffic flows, aircraft equipage, and air traffic control (ATC) needs. Variation of these factors between airports can make comparison difficult, whether between sites or over time. Recent studies, performed by The MITRE Corporation's Center for Advanced Aviation System Development (CAASD) on behalf of the Federal Aviation Administration (FAA), have led to the development of a methodology for analyzing traffic flow vertical profiles for the purpose of reducing fuel burn and emissions in transition airspace. The methodology is flexible enough to be meaningfully applied to airports across the United States National Airspace System (NAS), while still having the specificity to reflect site specific vertical profile improvements. For example, in one recent study using this standardized methodology, over 4,000 traffic flows were identified for 48 airports across the NAS. Results were examined at the Terminal Radar Approach Control (TRACON), airport, flow, and individual segment level of detail, enabling support for national planning efforts as well as local procedure design. Results are typically reviewed in either a tabular format or in an interactive 3-D environment.
{"title":"NAS-wide vertical profile analysis: Level segments in arrival and departure flows","authors":"S. Dorfman, J. Daily, T. Gonzalez, G. Kondo","doi":"10.1109/ICNSURV.2012.6218390","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218390","url":null,"abstract":"Low altitude level flight segments increase fuel burn and emissions for the aircraft flying them. The number and length of level segments flown during arrival and departure operations can be reduced by procedure design which leverages the advantages of Area Navigation (RNAV) to reduce actual level flight. Such design must take into account many factors including terrain, current route of a particular flow of air traffic, other proximate air traffic flows, aircraft equipage, and air traffic control (ATC) needs. Variation of these factors between airports can make comparison difficult, whether between sites or over time. Recent studies, performed by The MITRE Corporation's Center for Advanced Aviation System Development (CAASD) on behalf of the Federal Aviation Administration (FAA), have led to the development of a methodology for analyzing traffic flow vertical profiles for the purpose of reducing fuel burn and emissions in transition airspace. The methodology is flexible enough to be meaningfully applied to airports across the United States National Airspace System (NAS), while still having the specificity to reflect site specific vertical profile improvements. For example, in one recent study using this standardized methodology, over 4,000 traffic flows were identified for 48 airports across the NAS. Results were examined at the Terminal Radar Approach Control (TRACON), airport, flow, and individual segment level of detail, enabling support for national planning efforts as well as local procedure design. Results are typically reviewed in either a tabular format or in an interactive 3-D environment.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114829145","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218373
H. Crane, D. Thomson, K. Bolczak
Integrated surveillance is defined as the integration of information from cooperative and noncooperative Air Domain surveillance sources to create a common understanding (picture) of the realtime situation for providing safety, security, and efficiency in the Aviation Transportation System [1]. Integrated surveillance includes the production, dissemination, and archiving of air vehicle position and movement information (longitude, latitude, altitude, ground speed, and ground track), as well as associating this air vehicle position and movement information with relevant flight information (flight plan, aircraft and aircrew information, etc.). Integrated surveillance also includes the sharing and collaborative use of this information by government command and control centers to conduct operations.
{"title":"Integrated surveillance capability gap analysis","authors":"H. Crane, D. Thomson, K. Bolczak","doi":"10.1109/ICNSURV.2012.6218373","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218373","url":null,"abstract":"Integrated surveillance is defined as the integration of information from cooperative and noncooperative Air Domain surveillance sources to create a common understanding (picture) of the realtime situation for providing safety, security, and efficiency in the Aviation Transportation System [1]. Integrated surveillance includes the production, dissemination, and archiving of air vehicle position and movement information (longitude, latitude, altitude, ground speed, and ground track), as well as associating this air vehicle position and movement information with relevant flight information (flight plan, aircraft and aircrew information, etc.). Integrated surveillance also includes the sharing and collaborative use of this information by government command and control centers to conduct operations.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127880056","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218449
Sapna E. George, F. Wieland
Presents a collection of slides from the author's conference presentation. ◉ ACES has proven to be a useful tool, especially for NextGen concept analysis and benefits studies - ACES, developed by NASA, has many NextGen features “built in” - examples include time-based flow management, the ability to meet RTAs via KTG, the ability to specify arrival and departure routes and investigate direct routes (RNAV and Q-routes), the ability to model CNS, and other features ◉ ACES gets compared against real world data on a caseby- case basis as it is used - Several examples shown in this briefing - ACES is close to actual system but, as expected with any model, not exactly equal to it ◉ ACES run-time continues to improve - On track for a five-minute run time within 5 years (50K flights)
{"title":"The airspace concepts evaluation system: Recent improvements and analysis results","authors":"Sapna E. George, F. Wieland","doi":"10.1109/ICNSURV.2012.6218449","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218449","url":null,"abstract":"Presents a collection of slides from the author's conference presentation. ◉ ACES has proven to be a useful tool, especially for NextGen concept analysis and benefits studies - ACES, developed by NASA, has many NextGen features “built in” - examples include time-based flow management, the ability to meet RTAs via KTG, the ability to specify arrival and departure routes and investigate direct routes (RNAV and Q-routes), the ability to model CNS, and other features ◉ ACES gets compared against real world data on a caseby- case basis as it is used - Several examples shown in this briefing - ACES is close to actual system but, as expected with any model, not exactly equal to it ◉ ACES run-time continues to improve - On track for a five-minute run time within 5 years (50K flights)","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121788403","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218422
I. Gheorghisor, A. Leu
Standards are being developed for airport surface wireless networks. Such networks have been denoted as Airport Network and Location Equipment (ANLE) or Aeronautical Mobile Airport Communications System (AeroMACS). The term ANLE/AeroMACS will be used in this paper. The Federal Aviation Administration (FAA) plans to use portions of the 5000-5250 MHz band, including the 5091-5150 MHz subband, for the future implementation of ANLE/AeroMACS networks. When implemented, they must coexist with other radio-frequency (RF) systems operating in the same frequency band. The 5091-5150 MHz subband has also been allocated, on a co-primary basis, to non-geostationary mobile-satellite-service (MSS) feeder uplinks. Therefore, ANLE/AeroMACS networks need to meet the MSS RF interference (RFI) criterion identified by the ITU in order to coexist with MSS. The ANLE/AeroMACS network architecture is based on the IEEE 802.16-2009 standard, and uses a channel bandwidth of 5 MHz. To complement the initial 5-MHz scenario presented at the ICNS 2011 conference, additional scenarios are analyzed in this paper in order to more completely evaluate the impact of different 5-MHz channel configurations on ANLE/AeroMACS-to-MSS compatibility. These scenarios help determine the impact of various base station (BS) configurations and BS parameters. Our results show that, given the parameters of ANLE/AeroMACS networks and MSS feeder uplinks identified in the paper, the RFI criterion is met, and bandsharing between these systems is feasible.
{"title":"Compatibility of airport surface wireless networks in the 5091–5150 MHZ band","authors":"I. Gheorghisor, A. Leu","doi":"10.1109/ICNSURV.2012.6218422","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218422","url":null,"abstract":"Standards are being developed for airport surface wireless networks. Such networks have been denoted as Airport Network and Location Equipment (ANLE) or Aeronautical Mobile Airport Communications System (AeroMACS). The term ANLE/AeroMACS will be used in this paper. The Federal Aviation Administration (FAA) plans to use portions of the 5000-5250 MHz band, including the 5091-5150 MHz subband, for the future implementation of ANLE/AeroMACS networks. When implemented, they must coexist with other radio-frequency (RF) systems operating in the same frequency band. The 5091-5150 MHz subband has also been allocated, on a co-primary basis, to non-geostationary mobile-satellite-service (MSS) feeder uplinks. Therefore, ANLE/AeroMACS networks need to meet the MSS RF interference (RFI) criterion identified by the ITU in order to coexist with MSS. The ANLE/AeroMACS network architecture is based on the IEEE 802.16-2009 standard, and uses a channel bandwidth of 5 MHz. To complement the initial 5-MHz scenario presented at the ICNS 2011 conference, additional scenarios are analyzed in this paper in order to more completely evaluate the impact of different 5-MHz channel configurations on ANLE/AeroMACS-to-MSS compatibility. These scenarios help determine the impact of various base station (BS) configurations and BS parameters. Our results show that, given the parameters of ANLE/AeroMACS networks and MSS feeder uplinks identified in the paper, the RFI criterion is met, and bandsharing between these systems is feasible.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130435967","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218461
Michael A. Garcia, Jack Dolan, R. Mueller, Ralph Smith
{"title":"Alternate position determination for aviation using SBSS","authors":"Michael A. Garcia, Jack Dolan, R. Mueller, Ralph Smith","doi":"10.1109/ICNSURV.2012.6218461","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218461","url":null,"abstract":"","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134072639","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218385
S. AhmadBeygi, E. Bromberg, M. Elliott, S. Krishna, T. Lewis, L. Schultz, J. Wetherly, V. Sud
Successful implementation of NextGen will require a critical mass of aircraft to be equipped with a range of avionics in the areas of communication, navigation, and surveillance. The equipage process has faced impediments that have slowed equipage rates below targets. It is believed that a package of financial and operational incentives can help accelerate the equipage process by incentivizing and facilitating the use of NextGen equipage. This paper focuses on Traffic Flow Management (TFM) Operational Incentives (OPIs) that can be implemented in the near-term. These incentives can help accelerate the equipage process by providing short-term benefits to early adopters until the full benefits of equipage materialize in the far term. Also, implementing equipage-aware Traffic Management Initiatives (TMIs) can enable near-term implementation of equipage-dependent concepts in a mixed-equipage environment. This, in turn, can reduce the airlines' uncertainty with respect to equipage return on investment. In this paper we conduct a high-level quantitative analysis to gain insight into the ramifications of TFM OPIs under a range of equipage levels.
{"title":"Operational incentives in Traffic Flow Management","authors":"S. AhmadBeygi, E. Bromberg, M. Elliott, S. Krishna, T. Lewis, L. Schultz, J. Wetherly, V. Sud","doi":"10.1109/ICNSURV.2012.6218385","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218385","url":null,"abstract":"Successful implementation of NextGen will require a critical mass of aircraft to be equipped with a range of avionics in the areas of communication, navigation, and surveillance. The equipage process has faced impediments that have slowed equipage rates below targets. It is believed that a package of financial and operational incentives can help accelerate the equipage process by incentivizing and facilitating the use of NextGen equipage. This paper focuses on Traffic Flow Management (TFM) Operational Incentives (OPIs) that can be implemented in the near-term. These incentives can help accelerate the equipage process by providing short-term benefits to early adopters until the full benefits of equipage materialize in the far term. Also, implementing equipage-aware Traffic Management Initiatives (TMIs) can enable near-term implementation of equipage-dependent concepts in a mixed-equipage environment. This, in turn, can reduce the airlines' uncertainty with respect to equipage return on investment. In this paper we conduct a high-level quantitative analysis to gain insight into the ramifications of TFM OPIs under a range of equipage levels.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133064808","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218440
B. Korn, S. Tittel, C. Edinger
Integration of UAS (Unmanned Aircraft Systems) into non-segregated airspace remains a major goal to be solved for future acceptance of these systems in air transport. Up to now most civil and military UAS operations are taking place in segregated airspace so that collision avoidance and separation with other traffic is of no concern. To further enable the UAS operational scope, UA (Unmanned Aircraft) must be able to fly in airspace where other traffic is operating as well. This contribution is about possibilities of a stepwise integration of UAS in non-segregated airspace following the idea of the overall equivalent level of safety between manned and unmanned traffic. E.g. higher safety requirements for UAS specific ATM procedures (higher separation distances lateral and vertical) or adapted ACAS maneuvers and ACAS avoidance logic will relax requirements for e.g. the “Sense/Detect and Avoid” capability. The concepts are supported by a series of simulations that show how conflict potential between UAS and other traffic can be reduced without impacting manned traffic.
{"title":"Stepwise integration of UAS in non-segregated airspace - The potential of tailored uas atm procedures","authors":"B. Korn, S. Tittel, C. Edinger","doi":"10.1109/ICNSURV.2012.6218440","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218440","url":null,"abstract":"Integration of UAS (Unmanned Aircraft Systems) into non-segregated airspace remains a major goal to be solved for future acceptance of these systems in air transport. Up to now most civil and military UAS operations are taking place in segregated airspace so that collision avoidance and separation with other traffic is of no concern. To further enable the UAS operational scope, UA (Unmanned Aircraft) must be able to fly in airspace where other traffic is operating as well. This contribution is about possibilities of a stepwise integration of UAS in non-segregated airspace following the idea of the overall equivalent level of safety between manned and unmanned traffic. E.g. higher safety requirements for UAS specific ATM procedures (higher separation distances lateral and vertical) or adapted ACAS maneuvers and ACAS avoidance logic will relax requirements for e.g. the “Sense/Detect and Avoid” capability. The concepts are supported by a series of simulations that show how conflict potential between UAS and other traffic can be reduced without impacting manned traffic.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115348878","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218375
M. Garcia, R. Mueller, E. Innis, Boris Veytsman
Wide Area Multilateration (WAM) is being considered as one of the primary backup sources of air traffic surveillance to Automatic Dependent Surveillance-Broadcast (ADS-B) in the National Airspace System (NAS). Radar is currently the primary source of air traffic surveillance, with ADS-B poised to succeed radar leading into the FAA ADS-B Out mandate in 2020. WAM service could serve as both a transition to full ADS-B service and a cost-saving backup surveillance alternative to radar maintenance and expansion. One of the challenges associated with WAM is the accuracy of the aircraft's reported altitude. After engaging in a trade study to investigate various alternatives to correcting aircraft altitudes in a wide region for the FAA Colorado WAM Phase II program, Exelis determined that the aircraft altitude errors could be reduced significantly (less than 200') by integrating the Rapid Update Cycle (RUC) weather data grid generated by NOAA. The altitude correction trade study for WAM approach and results are discussed and analyzed.
{"title":"An enhanced altitude correction technique for improvement of WAM position accuracy","authors":"M. Garcia, R. Mueller, E. Innis, Boris Veytsman","doi":"10.1109/ICNSURV.2012.6218375","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218375","url":null,"abstract":"Wide Area Multilateration (WAM) is being considered as one of the primary backup sources of air traffic surveillance to Automatic Dependent Surveillance-Broadcast (ADS-B) in the National Airspace System (NAS). Radar is currently the primary source of air traffic surveillance, with ADS-B poised to succeed radar leading into the FAA ADS-B Out mandate in 2020. WAM service could serve as both a transition to full ADS-B service and a cost-saving backup surveillance alternative to radar maintenance and expansion. One of the challenges associated with WAM is the accuracy of the aircraft's reported altitude. After engaging in a trade study to investigate various alternatives to correcting aircraft altitudes in a wide region for the FAA Colorado WAM Phase II program, Exelis determined that the aircraft altitude errors could be reduced significantly (less than 200') by integrating the Rapid Update Cycle (RUC) weather data grid generated by NOAA. The altitude correction trade study for WAM approach and results are discussed and analyzed.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115366077","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 : 2012-04-24DOI: 10.1109/ICNSURV.2012.6218425
G. Schwoch, F. Knabe, R. Stump
High density terminal areas of large international airports present an extra challenge to 4D ATM concepts due to their traffic volume on the one hand and the traffic complexity on the other hand. This paper presents an approach to estimate requirements and costs for applying 4D ATM in a high density Terminal Manoeuvring Area in a specific example. A scenario Utopia is constructed to represent the upper boundary for improvements through 4D ATM in certain performance areas. Simultaneously, it is used to measure the associated costs and to describe constraining requirements. Utopia contains an arrival and departure route structure for a hub airport with lateral connections as short as possible and optimized profile descents. A realistic traffic example is used to identify problem areas to be solved. The paper describes the Utopia approach, preliminary considerations on selected topics, a specific example for an additional requirement and first numerical results.
{"title":"Estimating requirements and costs of 4D ATM in high density terminal areas","authors":"G. Schwoch, F. Knabe, R. Stump","doi":"10.1109/ICNSURV.2012.6218425","DOIUrl":"https://doi.org/10.1109/ICNSURV.2012.6218425","url":null,"abstract":"High density terminal areas of large international airports present an extra challenge to 4D ATM concepts due to their traffic volume on the one hand and the traffic complexity on the other hand. This paper presents an approach to estimate requirements and costs for applying 4D ATM in a high density Terminal Manoeuvring Area in a specific example. A scenario Utopia is constructed to represent the upper boundary for improvements through 4D ATM in certain performance areas. Simultaneously, it is used to measure the associated costs and to describe constraining requirements. Utopia contains an arrival and departure route structure for a hub airport with lateral connections as short as possible and optimized profile descents. A realistic traffic example is used to identify problem areas to be solved. The paper describes the Utopia approach, preliminary considerations on selected topics, a specific example for an additional requirement and first numerical results.","PeriodicalId":126055,"journal":{"name":"2012 Integrated Communications, Navigation and Surveillance Conference","volume":"174 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116004960","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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