Research On Ship Packet Scheduling Algorithm For Single Line Channel Based On Characteristics Of Ship Speed

With the development of large-scale and high-speed vessls and the increase of navigation density,the impact on navigation efficiency from mutual interference due to ship speed differences has also become increasingly apparent.In view of the existing problems of the research on evaluating the impact of vessel speed disturbances,this paper proposes a kind of evaluation method for navigation efficiency of single line channel which can reflect the impact of ship speed characteristics based on the analysis the space-time characteristics of ships when they are disturbed by ship speed.After that,the intrinsic relationship between ship speed characteristics and navigation efficiency is explored by simulating,and the most obvious factors for navigation efficiency is extracted.Finally,a ship packet scheduling algorithm for single line channel is proposed to reduce interference from ship speeds.The main research of this paper includes:Firstly,a navigation efficiency model of single line channel is constructed.In order to study the influence mechanism of speed characteristics to the ship navigation state,the single line channel is selected as the object of the research,and some characteristic parameters of ship deceleration behavior is extracted such as deceleration rate,deceleration distance and deceleration delay time based on analyzing the process of ship deceleration in the fairway.At the same time,the deceleration position of ship and critical condition of deceleration is determined based on the ship’s deceleration time-space relationship.At last,a navigation efficiency model is built,which takes the ship-speed interference level,channel service and number of ships deceleration as efficiency indicators.Secondly,analyzing the sensitivity of the navigation efficiency of single line waterway.The intrinsic relationship between ship speed characteristics and navigation efficiency under different conditions is explored by Monte Carlo simulation,which is based on building and verifying the validity of the ship traffic flow simulation model of single line channel by using Arena.After that,sensitivity of navigation efficiency is analyzed by the Morris screening method.The research shows that the mean values of ship speed,standard deviation and arrival rate willhave a significant impact on navigation efficiency,and the mean values of speed is the most sensitive factor of navigation efficiency,and when the average speed is less than 10 knots and the standard deviation is greater than 1.5 knots,the navigation efficiency of single line waterway will be significantly reduced.Finally,a ship packet scheduling algorithm for single line channel consisting of dynamic grouping rules and scheduling rules is designed,which is based on improving the average speed of ship as impetus according to the results of the sensitivity analysis.The dynamic grouping rules is based on the ship number threshold and time interval of ship arrive.The ship scheduling algorithm,which make the goal of reduce interference from ship speeds as the core,is proposed with fusing kinds of scheduling algorithms such minimum time delay,delay time threshold and priority sequences according to the actual navigation constraints.Simulation results show that the packet scheduling algorithm proposed in this paper can reduce the average level of interference from ship speeds by 30% to 40% in single line waterway.The research on the navigation efficiency evaluation method and ship packet scheduling algorithm for single line channel is a helpful exploration for the change mechanism of navigation efficiency under the influence of ship speed characteristics in restricted waters,and could provide a theoretical basis for actual ship traffic organization and optimization.