The existence of a hybrid relationship connecting departure delay and resulting en-route conflicts remains a significant gap in the air transportation literature.This paper aims to establish a hybrid relationship to q...The existence of a hybrid relationship connecting departure delay and resulting en-route conflicts remains a significant gap in the air transportation literature.This paper aims to establish a hybrid relationship to quantify the impact of departure delays on both the probability of en-route conflicts and the number of such conflicts.The proposed relationship is modelled using a binomial logistic regression framework,where the dependent variable,referred to as the conflict outcome at an en-route waypoint,is binary.It takes one of two possible levels:Conflict or No Conflict.The independent variables in the model are departure delay and the number of waypoints crossed since take-off.By utilising the logistic regression equation and assuming a binomial distribution for the number of conflicts,the model computes the expected number of conflicts at any given en-route waypoint.The logistic regression model parameters are estimated using maximum likelihood estimation,utilising data obtained from the Flight Data Processing System at Anna International Airport,Chennai,India.The relationship is then validated for multiple scenarios.Results and findings reinforce the hypothesised relationship,indicating an increase in delay and the number of waypoints crossed corresponds to higher conflict probabilities.Moreover,the impact of delay on conflict likelihood increases with an increase in the number of waypoints crossed.The hybrid relationship demonstrates flexibility and sufficient generalizability to account for multi-airport delay scenarios.Validation tests do not show any statistically significant difference between the observed conflict counts and the expected values predicted by the proposed relationship.Further post-estimate analyses confirm the robustness and stability of the relationship parameters.The primary recommendations hint towards the potential integration of this relationship into system-level delay management frameworks,encompassing both optimal departure and arrival management strategies.When incorporated,the proposed relationship enables the possibility of pragmatic,conflict-aware departure and arrival management.展开更多
In order to improve the accuracy of free flight conflict detection and reduce the false alarm rate, an improved flight conflict detection algorithm is proposed based on Gauss-Hermite particle filter（GHPF）. The algor...In order to improve the accuracy of free flight conflict detection and reduce the false alarm rate, an improved flight conflict detection algorithm is proposed based on Gauss-Hermite particle filter（GHPF）. The algorithm improves the traditional flight conflict detection method in two aspects：（i） New observation data are integrated into system state transition probability, and Gauss-Hermite Filter（GHF） is used for generating the importance density function.（ii） GHPF is used for flight trajectory prediction and flight conflict probability calculation. The experimental results show that the accuracy of conflict detection and tracing with GHPF is better than that with standard particle filter. The detected conflict probability is more precise with GHPF, and GHPF is suitable for early free flight conflict detection.展开更多
Describing spatial safety status is crucial for high-density air traffic involving multiple unmanned aerial vehicles （UAVs） in a complex environment. A probabilistic approach is proposed to measure safety situation ...Describing spatial safety status is crucial for high-density air traffic involving multiple unmanned aerial vehicles （UAVs） in a complex environment. A probabilistic approach is proposed to measure safety situation in congested airspace. The occupancy distribution of the airspace is represented with conflict probability between spatial positions and UAV. The concept of a safety envelope related to flight performance and response time is presented first instead of the conventional fixed-size protected zones around aircraft. Consequently, the conflict probability is performance-dependent, and effects of various UAVs on safety can be distinguished. The uncertainty of a UAV future position is explicitly accounted for as Brownian motion. An analytic approximate algorithm for the conflict probability is developed to decrease the computational consumption. The relationship between safety and flight performance are discussed for different response times and prediction intervals. To illustrate the applications of the approach, an experiment of three UAVs in formation flight is performed. In addition, an example of trajectory planning is simulated for one UAV flying over airspace where five UAVs exist. The validation of the approach shows its potential in guaranteeing flight safety in highly dynamic environment.展开更多
文摘The existence of a hybrid relationship connecting departure delay and resulting en-route conflicts remains a significant gap in the air transportation literature.This paper aims to establish a hybrid relationship to quantify the impact of departure delays on both the probability of en-route conflicts and the number of such conflicts.The proposed relationship is modelled using a binomial logistic regression framework,where the dependent variable,referred to as the conflict outcome at an en-route waypoint,is binary.It takes one of two possible levels:Conflict or No Conflict.The independent variables in the model are departure delay and the number of waypoints crossed since take-off.By utilising the logistic regression equation and assuming a binomial distribution for the number of conflicts,the model computes the expected number of conflicts at any given en-route waypoint.The logistic regression model parameters are estimated using maximum likelihood estimation,utilising data obtained from the Flight Data Processing System at Anna International Airport,Chennai,India.The relationship is then validated for multiple scenarios.Results and findings reinforce the hypothesised relationship,indicating an increase in delay and the number of waypoints crossed corresponds to higher conflict probabilities.Moreover,the impact of delay on conflict likelihood increases with an increase in the number of waypoints crossed.The hybrid relationship demonstrates flexibility and sufficient generalizability to account for multi-airport delay scenarios.Validation tests do not show any statistically significant difference between the observed conflict counts and the expected values predicted by the proposed relationship.Further post-estimate analyses confirm the robustness and stability of the relationship parameters.The primary recommendations hint towards the potential integration of this relationship into system-level delay management frameworks,encompassing both optimal departure and arrival management strategies.When incorporated,the proposed relationship enables the possibility of pragmatic,conflict-aware departure and arrival management.
基金Supported by the Joint Project of National Natural Science Foundation of ChinaCivil Aviation Administration of China(U1333116)
文摘In order to improve the accuracy of free flight conflict detection and reduce the false alarm rate, an improved flight conflict detection algorithm is proposed based on Gauss-Hermite particle filter（GHPF）. The algorithm improves the traditional flight conflict detection method in two aspects：（i） New observation data are integrated into system state transition probability, and Gauss-Hermite Filter（GHF） is used for generating the importance density function.（ii） GHPF is used for flight trajectory prediction and flight conflict probability calculation. The experimental results show that the accuracy of conflict detection and tracing with GHPF is better than that with standard particle filter. The detected conflict probability is more precise with GHPF, and GHPF is suitable for early free flight conflict detection.
基金supported by the National Basic Research Program of China (No.2011CB707002)
文摘Describing spatial safety status is crucial for high-density air traffic involving multiple unmanned aerial vehicles （UAVs） in a complex environment. A probabilistic approach is proposed to measure safety situation in congested airspace. The occupancy distribution of the airspace is represented with conflict probability between spatial positions and UAV. The concept of a safety envelope related to flight performance and response time is presented first instead of the conventional fixed-size protected zones around aircraft. Consequently, the conflict probability is performance-dependent, and effects of various UAVs on safety can be distinguished. The uncertainty of a UAV future position is explicitly accounted for as Brownian motion. An analytic approximate algorithm for the conflict probability is developed to decrease the computational consumption. The relationship between safety and flight performance are discussed for different response times and prediction intervals. To illustrate the applications of the approach, an experiment of three UAVs in formation flight is performed. In addition, an example of trajectory planning is simulated for one UAV flying over airspace where five UAVs exist. The validation of the approach shows its potential in guaranteeing flight safety in highly dynamic environment.
