CN-115830158-B - Ship traffic flow basic diagram drawing method based on microcosmic following theory

CN115830158BCN 115830158 BCN115830158 BCN 115830158BCN-115830158-B

Abstract

The invention relates to a ship traffic flow basic map drawing method based on a microcosmic following theory, which comprises the following steps of S1, obtaining AIS data in a selected area, carrying out AIS data pretreatment, establishing a rectangular coordinate system on the area, S2, dividing a single channel according to a dividing standard, carrying out primary screening on the pretreated AIS data, S3, drawing a ship track map according to conversion information, screening out an effective ship following data pair from the primary screened AIS data, S4, drawing a speed-following interval basic map, S5, drawing a speed-density basic map, S6, drawing a speed-traffic volume basic map, and S7, drawing a traffic volume-density basic map. According to the invention, the AIS data in the selected area is processed, effective ship following data is screened, the basic diagram of the offshore traffic flow is drawn completely according to the relation between the characteristic parameters of the traffic flow, and a reference basis is provided for the traffic characteristics and traffic conditions of the water area.

Inventors

Liu Diehua
GUO RUI
LI JINSONG
LIN FEI

Assignees

上海海事大学

Dates

Publication Date: 20260508
Application Date: 20221118
Priority Date: 20221110

Claims (7)

1. A basic drawing method of a ship traffic flow based on a microscopic following theory is characterized by comprising the following steps: S1, acquiring AIS data in a selected area, preprocessing the AIS data, and establishing a rectangular coordinate system on the area; s2, dividing a single channel according to a division standard, and performing primary screening on the pretreated AIS data; s3, drawing a ship track diagram according to the conversion information, and screening out effective ship following data pairs from the AIS data after primary screening; s4, calculating the following interval between the front ship and the rear ship, and drawing a speed-following interval basic diagram; S5, calculating the density of the ship, and drawing a speed-density basic diagram; s6, calculating the following time interval of the front ship and the rear ship, and drawing a speed-traffic volume basic diagram; S7, drawing a traffic volume-density basic diagram; in step S2, dividing a single channel according to five times of standard ship width, and using AIS data points of the ship in a channel coordinate system Value, single leg left line coordinates Coordinates of right line And width of single channel Judging whether the ship runs in the selected divided single channel or not, and taking the distance of AIS data points deviating from the right line of the single channel as : If it meets And is also provided with Finding out the ship data pairs entering and exiting the single channel in the adjacent time before and after the single channel, and ensuring that the rear ship does not have a chasing behavior in the single channel, so that the ship data pairs meeting the ship following condition are screened out initially; density of ship in step S5 : Wherein, the Representing the heel-to-heel spacing of the front and rear vessels, Is the length of a unit leg, For the number of vessels in the leg, a density is obtained To the following interval For the effective ship following data pairs screened in the step S3, drawing a speed-density basic diagram according to the speed data and the density data; Step S6 is followed by a time interval : Wherein, the Represents the following time interval of the ship, Representing the heel-to-heel spacing of the front and rear vessels, Representing the sailing speed of the rear ship, which is the time taken for the rear ship to travel to the position of the front ship at the current speed; According to the following time interval To obtain the traffic volume of the ship : Wherein, the In the unit of time of the device, For the ship traffic, get the ship traffic To keep the time interval And drawing a speed-traffic base map based on the speed data and the traffic data.
2. The method for drawing the basic map of the traffic flow of the ship based on the microscopic following theory according to claim 1, wherein in the step S1, AIS data of the channel area of the selected experimental water area is obtained by utilizing a point firing method, wherein the AIS data comprises ship navigation time, MMSI, ship longitude and latitude data and ship speed, if the ship travels from the selected water area, the number of intersection points of the ray which is sent by taking the ship as the center and the boundary of the closed area is odd, and if the ship travels outside the selected water area, the number of intersection points of the ray which is sent by taking the ship as the center and the boundary of the closed area is even.
3. The method for drawing the basic map of the ship traffic flow based on the microscopic following theory according to claim 1, wherein in the step S1, the AIS data is preprocessed, specifically, abnormal data is deleted, and interpolation processing is performed on the AIS data by adopting a cubic spline interpolation method at intervals of 20 seconds.
4. The method for drawing a basic map of a ship traffic flow based on a microscopic following theory as set forth in claim 1, wherein in said step S1, longitude and latitude dynamic information in the preprocessed AIS data is converted into ordinate and abscissa in a rectangular channel coordinate system, and the abscissa Representing the actual longitudinal distance of the vessel from the reference point, the ordinate Representing the actual lateral distance of the vessel from the reference point.
5. The method for drawing a basic map of a traffic flow of a ship based on the microscopic following theory according to claim 1, wherein said step S3 uses Coordinate value is ordinate, time Drawing a ship track diagram for the abscissa, finding a starting point of fluctuation of a front ship track curve according to the drawn ship navigation track diagram, and finding out corresponding time The method is characterized in that the front ship suddenly decelerates from the moment, the rear ship also decelerates along with the front ship, the front ship track fluctuation causes the rear ship track fluctuation, the data pair conforming to the rule is an effective ship following data pair, the data of one whole year is processed, and the effective ship following data pair conforming to the rule is screened.
6. The method for drawing a basic map of traffic flow of a ship based on microscopic relaxation theory according to claim 1, wherein the following interval in the step S4 is : Wherein, the Representing the heel-to-heel spacing of the front and rear vessels, Indicating the distance of the front ship in the direction of the longitudinal axis, And (3) representing the distance of the rear ship in the longitudinal axis direction, and drawing a speed-heel interval basic diagram according to the speed data and the heel interval data for the effective ship heel interval data pair screened in the step S3.
7. The method for drawing the basic map of the traffic flow of the ship based on the microscopic following theory according to claim 1, wherein the step S7 is characterized in that the basic map of the traffic flow-density is drawn according to the two characteristic parameters of the traffic flow and the density calculated in the step S5 and the step S6.

Description

Ship traffic flow basic diagram drawing method based on microcosmic following theory Technical Field The invention relates to the field of marine traffic flow, in particular to a basic drawing method of a ship traffic flow based on a microcosmic following theory. Background The water transportation industry is an important prop industry for social economic development, and the annual increasing freight transportation capacity and channel mileage indicate that the water transportation in China occupies larger and larger proportion in the economy and transportation industry, but the problems of channel congestion, running efficiency reduction, frequent water traffic accidents and the like are caused, so that huge losses are brought to world economy. The method makes full use of limited water area resources, improves the channel service quality, and ensures that the safety, high efficiency and economic navigation of the ship become the focus problem of sustainable development of water traffic. The basic diagram of the sea traffic flow can determine the maximum traffic capacity, the optimal density and the optimal navigational speed of the navigation channel theoretically, and provides scientific theoretical decision basis for traffic control of sea traffic authorities. However, due to the characteristics of large self-scale, slow rudder performance and the like of the ship, the maneuverability of the ship is far less than the flexibility of road vehicles, and the influence of meteorological factors such as wind, flow, waves and the like on the width of a ship track belt is also required to be considered when the ship sails in water. Due to the existence of the reasons, the following interval of the ship is larger when the ship runs in the navigation channel, so that the density in the navigation section is smaller, the traffic flow is not large, and the congestion condition basically does not occur, so that the basic diagram of the marine traffic flow cannot show the whole view. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a basic drawing method of a ship traffic flow based on a microscopic following theory by considering characteristic factors such as the following interval between two ships and the following time interval. The aim of the invention can be achieved by the following technical scheme: a basic drawing method of a ship traffic flow based on a microcosmic following theory comprises the following steps: S1, acquiring AIS data in a selected area, preprocessing the AIS data, and establishing a rectangular coordinate system on the area; s2, dividing a single channel according to a division standard, and performing primary screening on the pretreated AIS data; s3, drawing a ship track diagram according to the conversion information, and screening out effective ship following data pairs from the AIS data after primary screening; s4, calculating the following interval between the front ship and the rear ship, and drawing a speed-following interval basic diagram; S5, calculating the density of the ship, and drawing a speed-density basic diagram; s6, calculating the following time interval of the front ship and the rear ship, and drawing a speed-traffic volume basic diagram; And S7, drawing a traffic volume-density basic diagram. Further, in the step S1, AIS data of the channel area of the selected experimental water area is obtained by using a point-shooting method, wherein the AIS data includes a ship navigation time, MMSI (on-water mobile communication service identification code), ship longitude and latitude data and a ship speed, if the ship travels from the selected water area, the number of intersection points of the ray emitted by taking the ship as the center and the boundary of the closed area is odd, and if the ship travels outside the selected water area, the number of intersection points of the ray emitted by taking the ship as the center and the boundary of the closed area is even. Further, in the step S1, the AIS data is preprocessed, specifically, abnormal data is deleted, and a cubic spline interpolation method is adopted, and interpolation processing is performed on the AIS data at intervals of 20 seconds. Further, in the step S1, the latitude and longitude dynamic information in the preprocessed AIS data is converted into an ordinate and an abscissa in a rectangular channel coordinate system, the abscissa x represents an actual longitudinal distance between the ship and the reference point, and the ordinate y represents an actual transverse distance between the ship and the reference point. Further, in the step S2, a single channel is divided according to five times of the standard ship width d, and whether the ship runs in the selected divided single channel is judged according to the relationship among the y i value of the ship AIS data point in the channel coordinate system, the left line coordinate y 1 of the single channel, the rig