Self-adaptive threshold compression ship track compression method

An adaptive threshold and ship trajectory technology, applied in special data processing applications, electrical components, structured data retrieval, etc., can solve problems such as failure, poor compression effect, and difficult determination of threshold

Active Publication Date: 2020-06-30
SHANGHAI MARITIME UNIVERSITY
View PDF3 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art, and provide a method for compressing ship trajectory with adaptive threshold value, aiming at problems such as low efficiency of traditional ship trajectory compression, poor compression effect or even compression failure, difficulty in determining the threshold value, etc. , the method is simple and efficient

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Self-adaptive threshold compression ship track compression method
  • Self-adaptive threshold compression ship track compression method
  • Self-adaptive threshold compression ship track compression method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0081] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0082] as attached figure 1 As shown, an adaptive threshold ship trajectory compression method, taking the ship trajectory of the Yangtze River Estuary as an example, the specific steps are as follows:

[0083] Step 1. Data preprocessing;

[0084] Decode the AIS of a ship in a water area, and the decoded original ship trajectory is as follows figure 2 as shown, figure 2 It is the original trajectory map of the test set of the present invention that does not clear the abnormal trajectory points, and the ship trajectory after deleting the trajectory points with no static information and abnormal ship position is as follows: image 3 as shown, image 3 The ship trajectory map after removing the abnormal trajectory for the test set of the present invention.

[0085] Step 2: Coordinate conversion of track points—convert geographic coordinates...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a self-adaptive threshold compression ship track compression method which comprises the following specific steps: (1) data preprocessing: decoding a ship AIS (Automatic Identification System) of a water area and cleaning abnormal track points; (2) track point coordinate conversion: converting original geographic coordinates into Mercator projection; (3) calculating a point-to-line distance; (4) calculating an optimal threshold change rate; (5) calculating the threshold change rate of each track point; (6) compressing a single track; and (7) compressing all tracks. The method solves the problems that a traditional compression method is low in compression efficiency, poor in compression effect and even failed in compression, is only suitable for simultaneous compression of a single water area and is not suitable for simultaneous compression of multiple water areas, and has the advantages of being high in operation efficiency, stable in compression effect, free ofthreshold setting and the like.

Description

technical field [0001] The invention relates to the field of data compression, in particular to a ship track compression method with an adaptive threshold. Background technique [0002] A large amount of AIS data has problems such as storage difficulties, low calculation efficiency, and information redundancy. Therefore, it is very important to compress ship trajectory compression. In most studies, there is a problem of compression efficiency in the compression of ship trajectories; the determination of the distance threshold is based on the length and width of the ship, and there is a problem that the compression effect is poor or even fails due to the error of the ship information; the optimal threshold varies with the water area. It varies from person to person, and is often only suitable for a single water area but not for simultaneous compression of multiple water areas. Contents of the invention [0003] The purpose of the present invention is to overcome the defici...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G06F16/29H03M7/30
CPCG06F16/29H03M7/30
Inventor 唐春华肖英杰闫化然关克平
Owner SHANGHAI MARITIME UNIVERSITY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products