Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Nautical chart isobath smoothness assessment method

A technology of isobath and smoothness, applied in image analysis, image data processing, special data processing applications, etc., can solve problems such as evaluating the smoothness of isobath lines of nautical charts, and achieve reasonable display of seabed topography, accurate navigation capability, The effect of improving navigation safety

Active Publication Date: 2018-10-19
PLA DALIAN NAVAL ACADEMY
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

After deleting the small and curved isobaths, whether its expression on the chart can meet the requirements of the clarity of the chart, and whether the isobaths trend is smooth or not, currently mainly depends on the qualitative analysis of chart charters through manual visual interpretation. However, there is no published literature that can quantitatively evaluate the smoothness of isobaths in nautical charts

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
  • Nautical chart isobath smoothness assessment method
  • Nautical chart isobath smoothness assessment method
  • Nautical chart isobath smoothness assessment method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0039] The method for evaluating the smoothness of the isobaths of the nautical charts of the present invention uses a computer to realize the evaluation of the smoothness of the isobaths of the nautical charts. Suppose a certain isobath line l on the nautical chart, adopt the method of the present invention to evaluate the smoothness of the isobath line of the nautical chart, comprising the following steps, as Figure 4 Shown:

[0040] Step a, read all nodes p on the isobath line l on the chart 1 ,p 2 ,...,p n The plane position of (x i ,y i )(i=1,2,Λ,n);

[0041] Step b, extract the first node p from the isobath line l 1 , denoted as the current node p i ;

[0042] Step c, judge whether the current node is the first (or last) node on the isobath, if yes, go to step d; otherwise, extract the previous and next nodes of the current node on the isobath, and record it as the previous node p i-1 , back node p i+1 , go to step f;

[0043] Step d, judging whether the iso...

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 nautical chart isobath smoothness assessment method. The method comprises the following steps of reading plane positions of all nodes on an isobath of a nautical chart; defining a line segment formed by connecting the current node and the front node as a front line segment, a line segment formed by connecting the current node and the rear node as a rear line segment, anda line segment formed by connecting the front node and the rear node as a paired line segment; calculating a curvature of the isobath at the current node; calculating a smooth deviation of the isobathat the current node; calculating chord distances from the front line segment and the rear line segment to a circumscribed circle; and calculating a curvature average value, a smooth deviation maximumvalue and a chord distance maximum value of the isobath at all the nodes. According to the nautical chart isobath smoothness assessment method, the isobath smoothness assessment is realized through acomputer, so that the navigation capacity of a channel can be reflected more accurately, the submarine geomorphology can be reasonably displayed, and the navigation safety is improved.

Description

technical field [0001] The invention relates to the technical field of marine surveying and mapping, in particular to a method for evaluating contours of nautical charts. Background technique [0002] Isobath refers to a smooth curve connecting adjacent points of equal seabed depth calculated from the theoretical depth datum, that is, a closed curve passing through points of the same water depth. On nautical charts, isobaths play a very important role in ensuring navigation safety, accurately reflecting the navigability of waterways, and reasonably displaying seabed landforms. [0003] The isobath line representation of nautical charts first needs to ensure the safety of the ship’s maritime navigation, and secondly, it must express the navigable resources as fully as possible. In addition, in the process of synthesizing the isobaths of the nautical chart, in order to maintain the clarity of the drawing, it is necessary to delete the small bends on the isobaths. After delet...

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): G06F17/30G06T7/00G06T7/60
CPCG06T7/0002G06T7/60
Inventor 贾帅东张立华
Owner PLA DALIAN NAVAL ACADEMY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com