Pub Date : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222945
Sofie Eskilsson, Hanna Gustafsson, Suleman Khan, A. Gurtov
Several studies have shown insufficient security in air traffic communication. Controller-Pilot Datalink Communications (CPDLC) is used to communicate in text over the VHF data link, and Automatic Dependent Surveillance – Broadcast (ADS-B) determines the position of an aircraft. The vulnerability of air data communication was confirmed by successful experiments using Software-Defined Radio, where both CPDLC and ADS-B messages were transmitted in a safe environment. Neither ADS-B messages nor CPDLC messages are encrypted during transmission. The encoding of FANS-1/A messages was demonstrated, and the experiments showed that it is possible to send such messages with relatively inexpensive technology.
{"title":"Demonstrating ADS-B AND CPDLC Attacks with Software-Defined Radio","authors":"Sofie Eskilsson, Hanna Gustafsson, Suleman Khan, A. Gurtov","doi":"10.1109/ICNS50378.2020.9222945","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222945","url":null,"abstract":"Several studies have shown insufficient security in air traffic communication. Controller-Pilot Datalink Communications (CPDLC) is used to communicate in text over the VHF data link, and Automatic Dependent Surveillance – Broadcast (ADS-B) determines the position of an aircraft. The vulnerability of air data communication was confirmed by successful experiments using Software-Defined Radio, where both CPDLC and ADS-B messages were transmitted in a safe environment. Neither ADS-B messages nor CPDLC messages are encrypted during transmission. The encoding of FANS-1/A messages was demonstrated, and the experiments showed that it is possible to send such messages with relatively inexpensive technology.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"123 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126623504","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222989
Megan N Taylor, Asya Saldanli, A. Park
Advances in technology enable the deployment of an Urban Air Mobility (UAM) transportation system for congested metropolitan areas. A key element of UAM are vertiports, the infrastructure that electric vertical takeoff and landing vehicles (eVTOLs) use to land and take-off. A Vertiport Design Tool (VDT) was developed for use by architecture firms designing vertiports to evaluate operational trade-offs between vertiport surface area and vehicle throughput. A stochastic Monte Carlo simulation was developed to calculate vehicle throughput for different vertiport design alternatives, safety risk, and noise constraints. Results show that for every 420 m2 increase in vertiport surface area, the throughput increases by one vehicle per hour. For this, the time between vehicle arrivals also needs to decrease by 5 minutes for more arrivals to occur.
{"title":"Design of a Vertiport Design Tool","authors":"Megan N Taylor, Asya Saldanli, A. Park","doi":"10.1109/ICNS50378.2020.9222989","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222989","url":null,"abstract":"Advances in technology enable the deployment of an Urban Air Mobility (UAM) transportation system for congested metropolitan areas. A key element of UAM are vertiports, the infrastructure that electric vertical takeoff and landing vehicles (eVTOLs) use to land and take-off. A Vertiport Design Tool (VDT) was developed for use by architecture firms designing vertiports to evaluate operational trade-offs between vertiport surface area and vehicle throughput. A stochastic Monte Carlo simulation was developed to calculate vehicle throughput for different vertiport design alternatives, safety risk, and noise constraints. Results show that for every 420 m2 increase in vertiport surface area, the throughput increases by one vehicle per hour. For this, the time between vehicle arrivals also needs to decrease by 5 minutes for more arrivals to occur.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114836587","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222887
Mary Taylor, L. Flenniken, Jason Nembhard, Anderson Barreal
The Washington D.C. region is ranked 5th in the U.S. by GDP per capita and 3rd worst for traffic congestion causing friction in the local economy. A confluence of technological advances enables Urban Air Mobility (UAM) transportation systems to bypass road congestion and transport passengers in electric Vertical Takeoff and Landing vehicles. Analysis of travel demand profiles have identified the initial phase of a Rapid, Reliable Urban Mobility System (RRUMS) for the D.C. Region servicing private jet owners and first-class passengers from local airports to and from central business districts, assuming relaxed aerial vehicle and FAA restrictions. A stochastic simulation with random variables for vehicle speed, boarding times, vertiport operation times, and passenger inter-arrival times identified the need for a 5 node network with 70 vehicles, 3 landing pads, and 2 UAM vehicle parking space at the business Vertiports, servicing 369 flights per day. A Return on Investment of 122% can be achieved with a break-even in 2 years on an investment of $160M.
{"title":"Design of a Rapid, Reliable Urban Mobility System for the DC Region","authors":"Mary Taylor, L. Flenniken, Jason Nembhard, Anderson Barreal","doi":"10.1109/ICNS50378.2020.9222887","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222887","url":null,"abstract":"The Washington D.C. region is ranked 5th in the U.S. by GDP per capita and 3rd worst for traffic congestion causing friction in the local economy. A confluence of technological advances enables Urban Air Mobility (UAM) transportation systems to bypass road congestion and transport passengers in electric Vertical Takeoff and Landing vehicles. Analysis of travel demand profiles have identified the initial phase of a Rapid, Reliable Urban Mobility System (RRUMS) for the D.C. Region servicing private jet owners and first-class passengers from local airports to and from central business districts, assuming relaxed aerial vehicle and FAA restrictions. A stochastic simulation with random variables for vehicle speed, boarding times, vertiport operation times, and passenger inter-arrival times identified the need for a 5 node network with 70 vehicles, 3 landing pads, and 2 UAM vehicle parking space at the business Vertiports, servicing 369 flights per day. A Return on Investment of 122% can be achieved with a break-even in 2 years on an investment of $160M.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124479677","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222862
Eric J. Weis
In the search for increases in capacity, efficiencies, collaboration, and safety, organizations tend to constrain their focus on areas of technical solutions, automation advancements, process improvement, and systems development. While this type of approach is not without its merit, it bypasses the fundamental and foundational fact that regardless of environment, attempts to improve organizations must first acknowledge that we still work in a human-centric domain. Air traffic management will always remain a "people" business and any approach to improve organizational effectiveness must devote significant attention to this critical common denominator. Change efforts (even those designed to improve the safety culture) within our unique operational field usually advance at a careful, yet evolutionary pace. This paper argues that some areas, especially those related to human talent enhancement in cognitive, social and emotional domains, can evolve slightly faster than others when purposefully targeting controllers, managers, and leaders throughout the organization.
{"title":"Building Human Talent in Air Traffic Organizations","authors":"Eric J. Weis","doi":"10.1109/ICNS50378.2020.9222862","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222862","url":null,"abstract":"In the search for increases in capacity, efficiencies, collaboration, and safety, organizations tend to constrain their focus on areas of technical solutions, automation advancements, process improvement, and systems development. While this type of approach is not without its merit, it bypasses the fundamental and foundational fact that regardless of environment, attempts to improve organizations must first acknowledge that we still work in a human-centric domain. Air traffic management will always remain a \"people\" business and any approach to improve organizational effectiveness must devote significant attention to this critical common denominator. Change efforts (even those designed to improve the safety culture) within our unique operational field usually advance at a careful, yet evolutionary pace. This paper argues that some areas, especially those related to human talent enhancement in cognitive, social and emotional domains, can evolve slightly faster than others when purposefully targeting controllers, managers, and leaders throughout the organization.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130834083","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222882
Wenbo Li, Lei Yang, Yutong Chen, Haoran Zhang, Zheng Zhao
Continuous Descent Operations (CDO) can significantly reduce fuel burn and noise impact by keeping arriving aircraft at their cruise altitude for longer and then having a continuous descent at near-idle thrust with no level-flight segments. Designing concise, efficient and flexible arrival routes for high-level automation in generating conflict-free and economical trajectories, is a cornerstone for fully achieving CDO in high-density traffic scenarios. In this research, inspired by the Point Merge (PM), we design the Inverted Crown-Shaped Arrival Airspace (ICSAA) and its operational procedures in the terminal area to deliver Omni-directional CDO. In order to generate alternative optimal conflict-free trajectories for upcoming aircraft in an efficient manner, we established a multi-objective trajectory optimization model solved by Non-dominated Sorting Genetic Algorithm with Elitist Strategy (NSGA-Ⅱ). The Parote solutions of minimal fuel consumption and trip time were achieved in single aircraft and highly complex multi-aircraft scenarios. Results validated the effectiveness and acceptable computational cost (less than 5min in extremely high-density scenarios) of proposed algorithm. In addition, ICSAA seems to be a promising structure that could promote the application of CDO for its operational flexibility and capacity.
{"title":"Multi-Objective Optimization of CDO Trajectory in a Flexible Airspace Structure","authors":"Wenbo Li, Lei Yang, Yutong Chen, Haoran Zhang, Zheng Zhao","doi":"10.1109/ICNS50378.2020.9222882","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222882","url":null,"abstract":"Continuous Descent Operations (CDO) can significantly reduce fuel burn and noise impact by keeping arriving aircraft at their cruise altitude for longer and then having a continuous descent at near-idle thrust with no level-flight segments. Designing concise, efficient and flexible arrival routes for high-level automation in generating conflict-free and economical trajectories, is a cornerstone for fully achieving CDO in high-density traffic scenarios. In this research, inspired by the Point Merge (PM), we design the Inverted Crown-Shaped Arrival Airspace (ICSAA) and its operational procedures in the terminal area to deliver Omni-directional CDO. In order to generate alternative optimal conflict-free trajectories for upcoming aircraft in an efficient manner, we established a multi-objective trajectory optimization model solved by Non-dominated Sorting Genetic Algorithm with Elitist Strategy (NSGA-Ⅱ). The Parote solutions of minimal fuel consumption and trip time were achieved in single aircraft and highly complex multi-aircraft scenarios. Results validated the effectiveness and acceptable computational cost (less than 5min in extremely high-density scenarios) of proposed algorithm. In addition, ICSAA seems to be a promising structure that could promote the application of CDO for its operational flexibility and capacity.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115496805","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9223013
Chengtao Xu, Bowen Chen, Yongxin Liu, Fengyu He, Houbing Song
Underlying the easy accessibility and popularity of amateur unmanned aerial vehicles (UAVs, or drones), an effective multi-UAV detection method is desired. In this paper, we proposed a novel radio frequency (RF) signal detection method for recognizing multiple UAVs’ intrusion. The single transient control and video signal is transformed by Short Time Fourier Transform (STFT) to obtain its time-frequency-energy distribution features. To reduce the dimensionality of the RF feature vector, the principal component analysis (PCA) is applied in the signal characteristic subspace transformation. A remapped UAVs RF signal feature data is used in the training of the support vector machine (SVM) and K-nearest neighbor (KNN) algorithm for classifying the presence and number of intruding UAVs. In addition, a real-time test of UAV attacks on an airport area is implemented. The test results show that the accuracy for detecting the number of intruding UAVs is effective. This method could similarly apply to protect the public from unsafe and unauthorized UAV operations near security sensitive facilities.
{"title":"RF Fingerprint Measurement For Detecting Multiple Amateur Drones Based on STFT and Feature Reduction","authors":"Chengtao Xu, Bowen Chen, Yongxin Liu, Fengyu He, Houbing Song","doi":"10.1109/ICNS50378.2020.9223013","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9223013","url":null,"abstract":"Underlying the easy accessibility and popularity of amateur unmanned aerial vehicles (UAVs, or drones), an effective multi-UAV detection method is desired. In this paper, we proposed a novel radio frequency (RF) signal detection method for recognizing multiple UAVs’ intrusion. The single transient control and video signal is transformed by Short Time Fourier Transform (STFT) to obtain its time-frequency-energy distribution features. To reduce the dimensionality of the RF feature vector, the principal component analysis (PCA) is applied in the signal characteristic subspace transformation. A remapped UAVs RF signal feature data is used in the training of the support vector machine (SVM) and K-nearest neighbor (KNN) algorithm for classifying the presence and number of intruding UAVs. In addition, a real-time test of UAV attacks on an airport area is implemented. The test results show that the accuracy for detecting the number of intruding UAVs is effective. This method could similarly apply to protect the public from unsafe and unauthorized UAV operations near security sensitive facilities.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129962570","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 : 2020-09-01DOI: 10.1109/icns50378.2020.9222922
Leonhard Korowajczuk
The apron area is key for an airport operation, but today it lacks automation and visibility. The industry has assigned to it a valuable exclusive spectrum under ITU AM(R)S (Aeronautical Mobile (Radiocommunication) Service) and a dedicated technology known as Aeronautical Mobile Airport Communication System (AeroMACS), which should be used to provide the required automation and visibility. However, this spectrum must be used wisely, and the worst decision is to allow it to be used on as required basis. The spectrum usage should provide enough capacity for all applications that can be developed over time, including video capability across the apron surface. The visibility referred here, refers not only to the visual content, but also its analytical analysis and all kinds of data that can be beneficial to the airport operation. This information must be made available to airplanes and across the entire apron area, so it can be accessed from anywhere. This accessibility requires that the wireless coverage be planned from start to support the long-term technological applications that will be developed. This will allow the incremental implementation in a consistent and coherent manner. The apron design should address the requirements of the next 20 years, so its implementation will not be disruptive over time.In this paper, we analyze the impact of video streaming and how it can be addressed in a large airport. We also analyze the usage of available spectrum in the apron and dimension the wireless facilities required to cope with this demand.The proposed plan foresees the future demand and allows for its gradual implementation over the years without disruption.We suggest that a pilot deployment be done to validate/improve the assumptions and establish the guidelines for implementing apron visibility in the airports.
{"title":"Full Apron Visibility Design","authors":"Leonhard Korowajczuk","doi":"10.1109/icns50378.2020.9222922","DOIUrl":"https://doi.org/10.1109/icns50378.2020.9222922","url":null,"abstract":"The apron area is key for an airport operation, but today it lacks automation and visibility. The industry has assigned to it a valuable exclusive spectrum under ITU AM(R)S (Aeronautical Mobile (Radiocommunication) Service) and a dedicated technology known as Aeronautical Mobile Airport Communication System (AeroMACS), which should be used to provide the required automation and visibility. However, this spectrum must be used wisely, and the worst decision is to allow it to be used on as required basis. The spectrum usage should provide enough capacity for all applications that can be developed over time, including video capability across the apron surface. The visibility referred here, refers not only to the visual content, but also its analytical analysis and all kinds of data that can be beneficial to the airport operation. This information must be made available to airplanes and across the entire apron area, so it can be accessed from anywhere. This accessibility requires that the wireless coverage be planned from start to support the long-term technological applications that will be developed. This will allow the incremental implementation in a consistent and coherent manner. The apron design should address the requirements of the next 20 years, so its implementation will not be disruptive over time.In this paper, we analyze the impact of video streaming and how it can be addressed in a large airport. We also analyze the usage of available spectrum in the apron and dimension the wireless facilities required to cope with this demand.The proposed plan foresees the future demand and allows for its gradual implementation over the years without disruption.We suggest that a pilot deployment be done to validate/improve the assumptions and establish the guidelines for implementing apron visibility in the airports.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"24 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120896508","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9223005
Scott James, R. Raheb, Allison Hudak
We present an algorithm for the modeling and management of groups of autonomous Unmanned Aerial Vehicles (UAV). The algorithm extends a previous work in which aircraft were considered individually. In this paper, we decompose the algorithm into two computational levels: one for the centralized control of groups of UAVs, or "swarms", and one modeling the distributed behavior of individual UAVs within these swarms. We examine a number of scenarios and compare the impact of communication latency on the intra-swarm and inter-swarm separations.
{"title":"UAV Swarm Path Planning","authors":"Scott James, R. Raheb, Allison Hudak","doi":"10.1109/ICNS50378.2020.9223005","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9223005","url":null,"abstract":"We present an algorithm for the modeling and management of groups of autonomous Unmanned Aerial Vehicles (UAV). The algorithm extends a previous work in which aircraft were considered individually. In this paper, we decompose the algorithm into two computational levels: one for the centralized control of groups of UAVs, or \"swarms\", and one modeling the distributed behavior of individual UAVs within these swarms. We examine a number of scenarios and compare the impact of communication latency on the intra-swarm and inter-swarm separations.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":" 38","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133421119","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 : 2020-09-01DOI: 10.1109/ICNS50378.2020.9222903
Vanessa Kuroda, M. Egorov, Steven Munn, A. Evans
Effective Remote Identification of unmanned aircraft is critical to their integration into civil airspaces. This paper assesses the ability of proposed unlicensed technologies (Bluetooth and WiFi) to support Remote Identification, and also creates a framework for modeling communication performance for unmanned aircraft, both at scale. Through simulation, we show that most currently commercially available Bluetooth and WiFi implementations would require significant ground antenna support in order to be able to avoid saturation situations at even low demand rates. We also show the flexibility of the simulation framework to study regional coverage and the effect of tuning different parameters on performance.
{"title":"Unlicensed Technology Assessment for Uas Communications","authors":"Vanessa Kuroda, M. Egorov, Steven Munn, A. Evans","doi":"10.1109/ICNS50378.2020.9222903","DOIUrl":"https://doi.org/10.1109/ICNS50378.2020.9222903","url":null,"abstract":"Effective Remote Identification of unmanned aircraft is critical to their integration into civil airspaces. This paper assesses the ability of proposed unlicensed technologies (Bluetooth and WiFi) to support Remote Identification, and also creates a framework for modeling communication performance for unmanned aircraft, both at scale. Through simulation, we show that most currently commercially available Bluetooth and WiFi implementations would require significant ground antenna support in order to be able to avoid saturation situations at even low demand rates. We also show the flexibility of the simulation framework to study regional coverage and the effect of tuning different parameters on performance.","PeriodicalId":424869,"journal":{"name":"2020 Integrated Communications Navigation and Surveillance Conference (ICNS)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134223162","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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