CN104766081A - Method for extracting territorial sea baseline based on natural coastline data - Google Patents
Method for extracting territorial sea baseline based on natural coastline data Download PDFInfo
- Publication number
- CN104766081A CN104766081A CN201510122765.7A CN201510122765A CN104766081A CN 104766081 A CN104766081 A CN 104766081A CN 201510122765 A CN201510122765 A CN 201510122765A CN 104766081 A CN104766081 A CN 104766081A
- Authority
- CN
- China
- Prior art keywords
- point
- territorial
- distance
- distance threshold
- area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 45
- 238000007906 compression Methods 0.000 claims abstract description 11
- 230000006835 compression Effects 0.000 claims abstract description 11
- 239000003643 water by type Substances 0.000 claims description 38
- 230000011218 segmentation Effects 0.000 claims description 26
- 239000008239 natural water Substances 0.000 claims description 21
- 239000000284 extract Substances 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 230000005540 biological transmission Effects 0.000 claims description 3
- 238000011156 evaluation Methods 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 abstract 3
- 238000010586 diagram Methods 0.000 description 8
- 230000000694 effects Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 230000000717 retained effect Effects 0.000 description 3
- 238000013144 data compression Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000000605 extraction Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000013213 extrapolation Methods 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 230000005226 mechanical processes and functions Effects 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000013535 sea water Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Landscapes
- Revetment (AREA)
- Processing Or Creating Images (AREA)
Abstract
A method for extracting a territorial sea baseline based on natural coastline data mainly comprises a natural coastline thinning method based on an improved Douglas-Peucker algorithm and a territorial sea baseline encryption algorithm based on earth spherop geodesic line resolving, and territorial area baseline delimitation is conducted. According to the method for extracting the territorial sea baseline based on the natural coastline data, in the thinning process, natural coastline salient points which have a larger influence on a sea area are extracted and taken as segment points, then two adjacent segment points are taken as a first point and a tail point for data thinning, an optimal distance threshold is selected through a fitting curve based on a least square method, thinning is conducted segment by segment, and the natural maritime rights and interests can be guaranteed under the circumstance that higher precision and compression ratio are guaranteed. The encryption algorithm is based on the earth spherop geodesic line resolving on the ground, a geodesic line is fitted between adjacent territorial sea base points, and therefore encryption calculation is conducted on adjacent base points by using a geodetic theme resolving principle. Improvement is conducted on distance judgment conditions and encryption point positions in the calculation process, the calculation rate is increased, and the position distribution of the territorial sea base points is more reasonable.
Description
Technical field
The present invention relates to territorial waters basic point to determine and the method that baselines of territorial sea delimited, encrypt in particular to a kind of natural water front vacuate and territorial waters basic point and generate the method for baselines of territorial sea, for auxiliary maritime demarcation, conscientiously safeguard that China's maritime rights and interests provide technical support.
Background technology
21 century is century of ocean, contains the resources such as abundant oil gas, fishery, mineral products in ocean, and while facilitating the developing rapidly of national economy, also become the focus of various countries' contention, therefore, the delimitation on border, ocean between specification country, practice significance is great.The determination of territorial waters basic point and the delimitation of baselines of territorial sea, for safeguarding China's maritime rights and interests, consolidate coast defence construction, protect the marine environment, strengthen marine management etc. and have long-range strategic importance and major and immediate significance.
Baselines of territorial sea be coastal state for measuring the start line of Limits of Territorial Sea and territorial waters state some other outer limit of compass of competency, its marine site of prolonging raw one fixed width to ocean is exactly territorial waters.According to the regulation (hereinafter referred to as " pact ") of the United Nations Convention on the Law of the Sea, baselines of territorial sea are divided into normal baseline, straight line basis, mixed baseline three kinds.Normal baseline, namely along subtidal line during seawater ebb tide around continental coast and island; Straight line basis, i.e. littoral some basic points that most foreign aid selectes to extra large highlight and coastal foreign aid island in continent, then to couple together with straight line the broken line formed by adjacent basic point; Mixed baseline, is namely used alternatingly normal baseline and straight line basis.
Known natural water front, according to normal baseline extrapolation boundary line of territorial waters, can because primary data dot density be too high, the speed that impact calculates further, or make calculating serious complications.In order to simplify, first can choose shoreline feature point (i.e. vacuate) according to certain density and becoming one " direction line " to replace nature water front to extrapolate.The ripe algorithm of direction line problem is not also generated at present for natural water front vacuate.But general curve compression theory is very ripe, comprises interval and get a method, angle limit value method, raster method, hang down apart from limit value method, Douglas-Pu Kefa etc.Wherein, Douglas-Pu Ke algorithm is vacuate method the most classical, and algorithm realization is simple, and efficiency is high, and abbreviation is effective.
Douglas-Pu Ke algorithm carries out vacuate with whole piece curve, and its basic thought is: setpoint distance threshold value, then junction curve head and the tail point composition straight line; In the middle of calculating, each point is to the distance of this straight line, finds out ultimate range and ultimate range point; If be less than threshold value, then replace virgin curve with this straight line, if be greater than threshold value, with this point, line segment is divided into two sections; Repeat said process to these two sections, the point finally remained is data compression result.Douglas-Pu Ke algorithm be one from entirety to the vacuate method of local, compression curve and virgin curve deviation are not quite and compressibility is higher.Compression degree and precision depend on threshold value, and threshold value is larger, and compressibility is larger, but precision step-down; Threshold value is less, and compressibility is less, and precision uprises.
Although the vacuate effect of Douglas-Pu Ke algorithm is better than other several algorithms, but still there is certain defect: part Important Characteristic Points may be cast out; Self intersection phenomenon is easily there is when line style is more complicated or threshold value is larger; The common boundary compression of adjacent two linear targets is inconsistent; Topology is inconsistent causes landform distortion etc.
Known baselines of territorial sea, consecutive point can affect computational accuracy and accurate Drawing apart from too far away.When adopting straight line basis, international mainstream scholar advises that adjacent territorial waters basic point distance can not more than 24 nautical miles, therefore, for needing interpolated point (namely encrypting) apart from excessive adjacent basic point.
Summary of the invention
The technical problem to be solved in the present invention is: the above-mentioned defect overcoming prior art, proposes a kind of method extracting baselines of territorial sea based on natural water front data.
In order to solve the problems of the technologies described above, the technical scheme that the present invention proposes extracts the method for baselines of territorial sea, it is characterized in that, comprise the steps:
Step 1, choose salient point---for nature coastline unique point point set N, utilize vector cross-products formula to select salient point, and stored in point set M;
Step 2, choose waypoint---the head and the tail point in point set N is defaulted as waypoint, directly stored in segmentation point set T; And to calculate in point set M in all the other each points and point set N successively at adjacent 2 and form leg-of-mutton area value S, if S>=S
0, then in point set M, this point judges waypoint, stored in segmentation point set T, wherein, and S
0for the area threshold preset;
Step 3, determine the optimal distance threshold value D of each segmentation---for the nature coastline unique point point set between adjacent sectional point, selected optimal distance threshold value D;
Step 4, segment data vacuate---utilize waypoint nature coastline to be divided into some segmentation shore lines, head and the tail point respectively using adjacent two waypoints as segmentation shore line, using described optimal distance threshold value D as initial distance threshold value, segmentation uses Douglas-Pu Ke algorithm to carry out data vacuate to nature coastline, obtain some alternative basic points, the line of alternative basic point forms direction line;
Step 5, distance threshold adjust---and the distance threshold in segmentation shore line is finely tuned, makes oceanic area and vacuate precision reach balance, obtain revised alternative basic point and revised direction line;
Step 6, territorial waters basic point obtain---according to the United Nations Convention on the Law of the Sea, obtain according to revised alternative basic point the basic point that borders on the sea;
Step 7, territorial waters basic point encrypt---for arbitrary neighborhood two territorial waters basic points between geodesic line length L, if be greater than default encryption distance s, then on the geodesic line of these two territorial waters basic points, increase [L/S] individual pass point, make the geodesic line length between consecutive point be no more than encryption distance s; Wherein operational symbol [] representative rounds.
The present invention also has following further feature:
1, in step 2, area threshold S
0determine by following methods: calculate adjacent 2 triangle areas formed in each salient point and virgin curve respectively, because median is not by the impact of value bigger than normal or less than normal, therefore select the median of triangle area as area threshold S
0.
2, in step 3, utilize least square curve fit distance threshold with retain the relation of counting, selected optimal distance threshold value D, specific practice is, utilize the function formula of least square curve fit distance threshold and point, according to distance threshold-optimal fitting curve of counting, find the maximum curvature point that this curve declines fast, the distance threshold at this some place is optimal distance threshold value D, represents the maximum equilibrium point between compressibility and quality.
3, in step 5, make oceanic area and vacuate precision reach balance, evaluation factor comprises:
1), area ratio: the extra large land area ratio that direction line and natural water front enclose with interior water and inland respectively;
2), compressibility: the ratio of data volume before the data volume that Vector data compress methods falls and compression;
3), area of error: after vacuate, curve departs from the area sum of virgin curve, and after this index reflects vacuate, curve and virgin curve presses close to degree.
4, in step 7, the concrete steps of territorial waters basic point encryption are as follows:
If the projector distance sum between step a, adjacent territorial waters basic point in three coordinate axis of line under three-dimensional system of coordinate is greater than encryption distance s, then goes to step b, otherwise be not encrypted;
Step b, terrestrial coordinate according to two territorial waters basic points, utilize inverse solution of geodetic problem, obtain the geodesic line length L of two territorial waters basic points and square parallactic angle A;
If the geodesic line length L of the described two territorial waters basic points of step c is greater than encryption distance s, then need the encryption carrying out [L/S] individual point;
Steps d, according to direct solution of geodetic problem, with distance d, square parallactic angle A for known conditions, solve terrestrial coordinate and the reverse aximuth of first pass point; The reverse aximuth of first pass point deducts the square parallactic angle that 180 ° obtain first pass point; With the terrestrial coordinate of first pass point, square parallactic angle and encryption distance s for known conditions, inquire into terrestrial coordinate and its reverse aximuth of second pass point, by that analogy, until obtain the terrestrial coordinate of all pass points; Wherein d=S%s+0.5*s, operational symbol % represent remainder number.
5, in step b, use the anti-solution formula of the average argument of Gauss or the anti-resolving Algorithm of Bezier theme, calculate point-to-point transmission geodesic line length and positive reverse aximuth.
Extract a method for baselines of territorial sea based on natural water front data, mainly comprise based on the natural water front vacuate method of modified Douglas-Pu Ke algorithm and the baselines of territorial sea cryptographic algorithm resolved based on earth ellipsoid face geodesic line, to carry out baselines of territorial sea delimitation.The present invention extracts in vacuate process affects larger natural water front salient point as waypoint to oceanic area, then utilize adjacent sectional point as the head and the tail point of Douglas-Pu Ke algorithm, to select optimal distance threshold value based on the matched curve of least square method, carry out vacuate piecemeal, national marine rights and interests can be ensured when guarantee reaches degree of precision and compressibility.In cryptographic algorithm, algorithm based on the resolving of geodesic line, at adjacent territorial waters intercardinal matching geodesic line, and then utilizes earth motive calculate principle to be encrypted calculating for adjacent intercardinal on earth ellipsoid face.Adjust the distance in computation process Rule of judgment and pass point position is improved, and improve computation rate, the position distribution of territorial waters basic point is also more reasonable.Further, the extraction method of baselines of territorial sea of the present invention has higher operation efficiency.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, the present invention is further illustrated.
Fig. 1 modified segmentation Douglas-Pu Ke algorithm flow chart.
Fig. 2 tradition and natural water front vacuate exemplary plot under innovatory algorithm.
Fig. 3 Distance Judgment key diagram.
The cryptographic algorithm process flow diagram that Fig. 4 resolves based on earth ellipsoid face geodesic line.
Fig. 5 unencrypted baselines of territorial sea schematic diagram.
The baselines of territorial sea schematic diagram of Fig. 6 encryption.
Embodiment
Below for South China Sea, elaborate the present invention with reference to the accompanying drawings, make technology path of the present invention and operation steps more clear.
The present embodiment extracts the method for baselines of territorial sea based on natural water front data, and form by modified segmentation Douglas-Pu Ke algorithm (process flow diagram is shown in Fig. 1) with based on the cryptographic algorithm (process flow diagram is shown in Fig. 4) that earth ellipsoid face geodesic line resolves, overall step is as follows:
Step 1, choose salient point---for nature coastline unique point point set N, utilize vector cross-products formula to select salient point, and stored in point set M.
The feature of Douglas-Pu Ke algorithm is the increase along with distance threshold, and compressibility becomes large, but head and the tail point is retained all the time.Therefore adopt segmentation Douglas-Pu Ke algorithm to carry out curve compression, waypoint, as the head and the tail point of segmentation Douglas-Pu Ke algorithm, can be retained all the time, and compression result farthest retains the large unique point of Curvature varying.And generate in the line process of direction at natural water front vacuate, for ensureing national marine rights and interests, safeguarding that National Sea is complete, under United Nations Convention on the Law of the Sea framework, shore line salient point should be retained as much as possible, cast out concave point.Based on above-mentioned 2 considerations, the present invention's proposition take salient point as the segmentation Douglas-Pu Ke algorithm of waypoint, using the head and the tail point of salient point as each vacuate segmentation, farthest remains salient point.This algorithm under the prerequisite ensureing National Sea area, can improve precision and compressibility to greatest extent.Therefore first algorithm extracts nature water front salient point.
Step 2, choose waypoint---the head and the tail point in point set N is defaulted as waypoint, directly stored in segmentation point set T; And to calculate in point set M in all the other each points and point set N successively at adjacent 2 and form leg-of-mutton area value S, if S>=S
0, then in point set M, this point judges waypoint, stored in segmentation point set T, wherein, and S
0for the area threshold preset.
Utilizing area threshold to choose waypoint is one of important step of this algorithm, the natural water front salient point number gone out owing to utilizing vector cross-products formulas Extraction is often too much, if using all salient points as waypoint, will the effect of compression do not reached, therefore select part salient point as waypoint.Based on the demand of national marine interests, choose herein and contribute large part salient point as waypoint to ocean area.Concrete grammar is: setting area threshold S0, calculates adjacent 2 gore product value S formed on each salient point and virgin curve successively, if S is greater than S0, then retain this point, until judge a little complete.
Wherein, area threshold S
0determine by following methods: calculate adjacent 2 triangle areas formed in each salient point and virgin curve respectively, because median is not by the impact of value bigger than normal or less than normal, therefore select the median of triangle area as area threshold S
0.
Step 3, determine the optimal distance threshold value D of each segmentation---for the nature coastline unique point point set between adjacent sectional point, selected optimal distance threshold value D.
In this step, utilize least square curve fit distance threshold with retain the relation of counting, selected optimal distance threshold value D, specific practice is, utilize the function formula of least square curve fit distance threshold and point, according to distance threshold-optimal fitting curve of counting, find the maximum curvature point that this curve declines fast, the distance threshold at this some place is optimal distance threshold value D, represents the maximum equilibrium point between compressibility and quality.
Step 4, segment data vacuate (segmentation uses Douglas-Pu Ke algorithm)---utilize waypoint nature coastline to be divided into some segmentation shore lines, head and the tail point respectively using adjacent two waypoints as segmentation shore line, using described optimal distance threshold value D as initial distance threshold value, segmentation uses Douglas-Pu Ke algorithm to carry out data vacuate to nature coastline, obtain some alternative basic points, the line of alternative basic point forms direction line.
From first pair of adjacent sectional point, until last waypoint, for the optimal distance threshold value D that each segmentation utilizes step 3 to obtain, junction curve head and the tail point composition straight line; In the middle of calculating, each point is to the distance of this straight line, finds out ultimate range and ultimate range point; If be less than optimal distance threshold value D, then replace virgin curve with this straight line, if be greater than optimal distance threshold value D, with this point, line segment is divided into two sections; Repeat said process to these two sections, the point finally remained is data compression result.
Step 5, distance threshold adjust---and the distance threshold in segmentation shore line is finely tuned, makes oceanic area and vacuate precision reach balance, obtain revised alternative basic point and revised direction line.
In this step, make oceanic area and vacuate precision reach balance, evaluation factor comprises:
1), area ratio: the extra large land area ratio that direction line and natural water front enclose with interior water and inland respectively;
2), compressibility: the ratio of data volume before the data volume that Vector data compress methods falls and compression;
3), area of error: after vacuate, curve departs from the area sum of virgin curve, and after this index reflects vacuate, curve and virgin curve presses close to degree.
Through above-mentioned process, final direction line vacuate result can be obtained.As shown in Fig. 2 example, under various threshold value, the area ratio utilizing algorithm of the present invention to obtain adds 6.99%, 2.55%, 1.19%, 1.30% than traditional Douglas-Pu Ke algorithm respectively.And under four kinds of threshold values herein the direction line that obtains of algorithm all to get close to nature water front than traditional algorithm gained direction line, area of error decreases 0.03km2,0.44 km2,0.11 km2,0.08 km2 than traditional algorithm respectively.Can ensure the integrality of oceanic area when guarantee reaches degree of precision and compressibility, performance is obviously better than traditional algorithm, obtains better effect.
Step 6, territorial waters basic point obtain---according to the United Nations Convention on the Law of the Sea, obtain according to revised alternative basic point the basic point that borders on the sea.
Step 7, territorial waters basic point encrypt---for arbitrary neighborhood two territorial waters basic points between geodesic line length L, if be greater than default encryption distance s, then on the geodesic line of these two territorial waters basic points, increase [L/S] individual pass point, make the geodesic line length between consecutive point be no more than encryption distance s; Wherein operational symbol [] representative rounds.
In the present embodiment, the concrete steps of territorial waters basic point encryption are as follows:
If the projector distance sum between step a, adjacent territorial waters basic point in three coordinate axis of line under three-dimensional system of coordinate is greater than encryption distance s, then goes to step b, otherwise be not encrypted.
Distance Judgment is the most desirable is directly contrast in encryption distance geodesic line distance between 2 o'clock, but the calculating of geodesic line is too loaded down with trivial details, therefore Rule of judgment of adjusting the distance in the present embodiment is optimized.As Fig. 3, suppose have adjacent 2 A (x1, y1, z1) and D (x2, y2, z2), its geodesic line on ellipsoid is the camber line of connection 2.The length of camber line is less than the length of line segment AB+BC+CD, the length of (| x2-x1|+|y2-y1|+|z2-z1|) is less than encryption distance s so projector distance sum between 2 in three coordinate axis of line under three-dimensional system of coordinate, illustrate that this geodesic line length of 2 must be less than encryption distance s, do not need encryption.Only having and work as | x2-x1|+|y2-y1|+|z2-z1| is greater than encryption distance s, just needs to utilize the earth normal solution to calculate geodesic line length and judges further.In actual mechanical process, first terrestrial coordinate is converted to rectangular space coordinate.Due to most of territorial waters basic point close together, the Distance Judgment of improvement can greatly reduce workload, improves operation efficiency.
Step b, terrestrial coordinate according to two territorial waters basic points, utilize inverse solution of geodetic problem, obtain the geodesic line length L of two territorial waters basic points and square parallactic angle A.Inverse solution of geodetic problem is the terrestrial coordinate of known 2, calculates point-to-point transmission geodesic line length and positive and negative azimuthal method, and conventional specific algorithm has the anti-solution formula of the average argument of Gauss and Bezier theme is counter separates.
If the geodesic line length L of the described two territorial waters basic points of step c is greater than encryption distance s, then need the encryption carrying out [L/S] individual point.
Steps d, according to direct solution of geodetic problem, with distance d, square parallactic angle A for known conditions, solve terrestrial coordinate and the reverse aximuth of first pass point; The reverse aximuth of first pass point deducts the square parallactic angle that 180 ° obtain first pass point; With the terrestrial coordinate of first pass point, square parallactic angle and encryption distance s for known conditions, inquire into terrestrial coordinate and its reverse aximuth of second pass point, by that analogy, until obtain the terrestrial coordinate of all pass points; Wherein d=S%s+0.5*s, operational symbol % represent remainder number.
Be illustrated in figure 5 unencrypted baselines of territorial sea schematic diagram, Fig. 6 is encryption distance s=24 encryption schematic diagram in the sea.
When carrying out normal solution and resolving pass point, if be encrypted from starting point to encrypt distance s, easily cause final pass point from terminating point excessively close to, be unfavorable for display effect and performance baselines of territorial sea tracing pattern.Therefore all pass points are moved to the middle position of geodesic line by required distance, make the distance of last pass point of Distance geometry of first pass point and starting point Q1 and terminating point Q2 roughly the same, move distance d by all pass points to starting point Q1 direction.Concrete way is when solving first pass point, separates using distance d as known elements is counter.Pass point afterwards, solves to encrypt distance s as known elements.Concrete formula refers in steps d.
The cryptographic algorithm of baselines of territorial sea adopts earth motive calculate method, and adjust the distance Rule of judgment and encrypted location improve, and are encrypted baselines of territorial sea by matching geodesic line.Pass point can be used as the auxiliary point of baselines of territorial sea, generates the baselines of territorial sea meeting international norm, meets the fairness doctrine of maritime demarcation, is conducive to the expansion of next step maritime demarcation operation.The Distance Judgment condition improved can simplify calculating, raises the efficiency, especially for the situation that part territorial waters basic point is intensive.Encrypted location after improvement is expressed, and makes pass point position distribution reasonable, obtains good display effect.
In addition to the implementation, the present invention can also have other embodiments.All employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop on the protection domain of application claims.
Claims (6)
1. extract the method for baselines of territorial sea based on natural water front data, it is characterized in that, comprise the steps:
Step 1, choose salient point---for nature coastline unique point point set N, utilize vector cross-products formula to select salient point, and stored in point set M;
Step 2, choose waypoint---the head and the tail point in point set N is defaulted as waypoint, directly stored in segmentation point set T; And to calculate in point set M in all the other each points and point set N successively at adjacent 2 and form leg-of-mutton area value S, if S>=S
0, then in point set M, this point judges waypoint, stored in segmentation point set T, wherein, and S
0for the area threshold preset;
Step 3, determine the optimal distance threshold value D of each segmentation---for the nature coastline unique point point set between adjacent sectional point, selected optimal distance threshold value D;
Step 4, segment data vacuate---utilize waypoint nature coastline to be divided into some segmentation shore lines, head and the tail point respectively using adjacent two waypoints as segmentation shore line, using described optimal distance threshold value D as initial distance threshold value, segmentation uses Douglas-Pu Ke algorithm to carry out data vacuate to nature coastline, obtain some alternative basic points, the line of alternative basic point forms direction line;
Step 5, distance threshold adjust---and the distance threshold in segmentation shore line is finely tuned, makes oceanic area and vacuate precision reach balance, obtain revised alternative basic point and revised direction line;
Step 6, territorial waters basic point obtain---according to the United Nations Convention on the Law of the Sea, obtain according to revised alternative basic point the basic point that borders on the sea;
Step 7, territorial waters basic point encrypt---for arbitrary neighborhood two territorial waters basic points between geodesic line length L, if be greater than default encryption distance s, then on the geodesic line of these two territorial waters basic points, increase [L/S] individual pass point, make the geodesic line length between consecutive point be no more than encryption distance s; Wherein operational symbol [] representative rounds.
2. the method extracting baselines of territorial sea based on natural water front data according to claim 1, is characterized in that: in step 2, area threshold S
0determine by following methods: calculate adjacent 2 triangle areas formed in each salient point and virgin curve respectively, because median is not by the impact of value bigger than normal or less than normal, therefore select the median of triangle area as area threshold S
0.
3. the method extracting baselines of territorial sea based on natural water front data according to claim 1; it is characterized in that: in step 3; utilize least square curve fit distance threshold with retain the relation of counting; selected optimal distance threshold value D; specific practice is; utilize the function formula of least square curve fit distance threshold and point; according to distance threshold-optimal fitting curve of counting; find the maximum curvature point that this curve declines fast; the distance threshold at this some place is optimal distance threshold value D, represents the maximum equilibrium point between compressibility and quality.
4. the method extracting baselines of territorial sea based on natural water front data according to claim 1, it is characterized in that: in step 5, make oceanic area and vacuate precision reach balance, evaluation factor comprises:
1), area ratio: the extra large land area ratio that direction line and natural water front enclose with interior water and inland respectively;
2), compressibility: the ratio of data volume before the data volume that Vector data compress methods falls and compression;
3), area of error: after vacuate, curve departs from the area sum of virgin curve, and after this index reflects vacuate, curve and virgin curve presses close to degree.
5. the method extracting baselines of territorial sea based on natural water front data according to claim 1, is characterized in that: in step 7, and the concrete steps of territorial waters basic point encryption are as follows:
If the projector distance sum between step a, adjacent territorial waters basic point in three coordinate axis of line under three-dimensional system of coordinate is greater than encryption distance s, then goes to step b, otherwise be not encrypted;
Step b, terrestrial coordinate according to two territorial waters basic points, utilize inverse solution of geodetic problem, obtain the geodesic line length L of two territorial waters basic points and square parallactic angle A;
If the geodesic line length L of the described two territorial waters basic points of step c is greater than encryption distance s, then need the encryption carrying out [L/S] individual point;
Steps d, according to direct solution of geodetic problem, with distance d, square parallactic angle A for known conditions, solve terrestrial coordinate and the reverse aximuth of first pass point; The reverse aximuth of first pass point deducts the square parallactic angle that 180 ° obtain first pass point; With the terrestrial coordinate of first pass point, square parallactic angle and encryption distance s for known conditions, inquire into terrestrial coordinate and its reverse aximuth of second pass point, by that analogy, until obtain the terrestrial coordinate of all pass points; Wherein d=S%s+0.5*s, operational symbol % represent remainder number.
6. the method extracting baselines of territorial sea based on natural water front data according to claim 5, is characterized in that: in step b, uses the anti-solution formula of the average argument of Gauss or the anti-resolving Algorithm of Bezier theme, calculates point-to-point transmission geodesic line length and positive reverse aximuth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510122765.7A CN104766081B (en) | 2015-03-19 | 2015-03-19 | Method based on natural water front data extraction baselines of territorial sea |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510122765.7A CN104766081B (en) | 2015-03-19 | 2015-03-19 | Method based on natural water front data extraction baselines of territorial sea |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104766081A true CN104766081A (en) | 2015-07-08 |
| CN104766081B CN104766081B (en) | 2017-12-29 |
Family
ID=53647895
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510122765.7A Expired - Fee Related CN104766081B (en) | 2015-03-19 | 2015-03-19 | Method based on natural water front data extraction baselines of territorial sea |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104766081B (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106528622A (en) * | 2016-10-08 | 2017-03-22 | 南通赛洋电子有限公司 | S57 sea chart data-oriented thinning method |
| CN107644069A (en) * | 2017-09-11 | 2018-01-30 | 千寻位置网络有限公司 | High density Monitoring Data vacuates method |
| CN107907101A (en) * | 2017-11-16 | 2018-04-13 | 彭认灿 | The geodesic interpolating method of the earth line length limit difference constraint |
| CN107917694A (en) * | 2017-11-16 | 2018-04-17 | 董箭 | The geodesic interpolating method of geodesic sagitta limit difference constraint |
| CN111006638A (en) * | 2019-12-18 | 2020-04-14 | 中国人民解放军海军大连舰艇学院 | Method for optimally selecting territorial sea base points |
| CN111159321A (en) * | 2019-12-13 | 2020-05-15 | 智慧航海（青岛）科技有限公司 | Ship track data screening method and device |
| CN111399493A (en) * | 2018-12-29 | 2020-07-10 | 北京奇虎科技有限公司 | Path display method and device of intelligent equipment |
| CN111641632A (en) * | 2020-05-28 | 2020-09-08 | 青岛铁木真软件技术有限公司 | Data compression method, system, device and storage medium |
| CN112562079A (en) * | 2020-12-22 | 2021-03-26 | 中铁第四勘察设计院集团有限公司 | Method, device and equipment for thinning topographic section data |
| CN113360837A (en) * | 2021-07-28 | 2021-09-07 | 国家海洋信息中心 | Sea area middle line demarcation method based on earth ellipsoid |
| CN117082474A (en) * | 2023-10-17 | 2023-11-17 | 国家海洋局北海预报中心((国家海洋局青岛海洋预报台)(国家海洋局青岛海洋环境监测中心站)) | System for acquiring marine environment forecast data in real time by scientific investigation ship |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104008276A (en) * | 2014-05-08 | 2014-08-27 | 中国科学院南海海洋研究所 | Sea power indexes and method for calculating island reef marine rights and interests quantitatively |
-
2015
- 2015-03-19 CN CN201510122765.7A patent/CN104766081B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104008276A (en) * | 2014-05-08 | 2014-08-27 | 中国科学院南海海洋研究所 | Sea power indexes and method for calculating island reef marine rights and interests quantitatively |
Non-Patent Citations (2)
| Title |
|---|
| JING YU等: ""An Improved Douglas-Peucker Algorithm Aimed at Simplifying Natural Shoreline into Direction-line"", 《2013 21ST INTERNATIONAL CONFERENCE》 * |
| 姚晓静等: ""基于遥感技术的近30 a 海南岛海岸线时空变化"", 《自燃资源学报》 * |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106528622B (en) * | 2016-10-08 | 2019-05-14 | 南通赛洋电子有限公司 | It is a kind of to vacuate method towards S57 chart data |
| CN106528622A (en) * | 2016-10-08 | 2017-03-22 | 南通赛洋电子有限公司 | S57 sea chart data-oriented thinning method |
| CN107644069B (en) * | 2017-09-11 | 2021-03-19 | 千寻位置网络有限公司 | Method for thinning high-density monitoring data |
| CN107644069A (en) * | 2017-09-11 | 2018-01-30 | 千寻位置网络有限公司 | High density Monitoring Data vacuates method |
| CN107907101A (en) * | 2017-11-16 | 2018-04-13 | 彭认灿 | The geodesic interpolating method of the earth line length limit difference constraint |
| CN107917694A (en) * | 2017-11-16 | 2018-04-17 | 董箭 | The geodesic interpolating method of geodesic sagitta limit difference constraint |
| CN107907101B (en) * | 2017-11-16 | 2020-09-11 | 彭认灿 | Large ground wire interpolation method based on large ground wire length tolerance constraint |
| CN111399493A (en) * | 2018-12-29 | 2020-07-10 | 北京奇虎科技有限公司 | Path display method and device of intelligent equipment |
| CN111159321A (en) * | 2019-12-13 | 2020-05-15 | 智慧航海（青岛）科技有限公司 | Ship track data screening method and device |
| CN111006638A (en) * | 2019-12-18 | 2020-04-14 | 中国人民解放军海军大连舰艇学院 | Method for optimally selecting territorial sea base points |
| CN111641632A (en) * | 2020-05-28 | 2020-09-08 | 青岛铁木真软件技术有限公司 | Data compression method, system, device and storage medium |
| CN112562079A (en) * | 2020-12-22 | 2021-03-26 | 中铁第四勘察设计院集团有限公司 | Method, device and equipment for thinning topographic section data |
| CN112562079B (en) * | 2020-12-22 | 2022-05-13 | 中铁第四勘察设计院集团有限公司 | Method, device and equipment for thinning topographic section data |
| CN113360837A (en) * | 2021-07-28 | 2021-09-07 | 国家海洋信息中心 | Sea area middle line demarcation method based on earth ellipsoid |
| CN113360837B (en) * | 2021-07-28 | 2023-03-10 | 国家海洋信息中心 | Sea area middle line demarcation method based on earth ellipsoid |
| CN117082474A (en) * | 2023-10-17 | 2023-11-17 | 国家海洋局北海预报中心((国家海洋局青岛海洋预报台)(国家海洋局青岛海洋环境监测中心站)) | System for acquiring marine environment forecast data in real time by scientific investigation ship |
| CN117082474B (en) * | 2023-10-17 | 2024-02-02 | 国家海洋局北海预报中心((国家海洋局青岛海洋预报台)(国家海洋局青岛海洋环境监测中心站)) | System for acquiring marine environment forecast data in real time by scientific investigation ship |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104766081B (en) | 2017-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104766081A (en) | Method for extracting territorial sea baseline based on natural coastline data | |
| Fietta et al. | A practitioner's guide to maritime boundary delimitation | |
| CN101739887B (en) | Method and device for acquiring three-dimensional paleotopographic map | |
| CN106022259A (en) | Laser-point cloud based method for extracting mountainous road by use of three-dimensional characteristic description model | |
| CN109960838B (en) | River terrain automatic generation method for embodying river basic characteristics | |
| CN102831645A (en) | Method for establishing digital elevation model applied to submarine topography | |
| CN109544691B (en) | MF (multi-frequency) method for automatically fusing multi-source heterogeneous water depth data to construct high-resolution DBM (database management system) | |
| CN109033494A (en) | A kind of coastal remote region tidal level projectional technique | |
| CN110135056A (en) | Bridge pier effectively blocks water the fast automatic analysis method of ratio in a kind of river | |
| Pan et al. | Impacts of deep waterway project on morphological changes within the north passage of the Changjiang Estuary, China | |
| CN108469263A (en) | A kind of method and system carrying out form point optimization based on curvature | |
| Zhou et al. | Compressing AIS trajectory data based on the multi-objective peak Douglas–Peucker algorithm | |
| Hodgson et al. | The technical delimitation of a modern equidistant boundary | |
| CN104123671B (en) | Meteorological reference station partition method | |
| WO2023116825A1 (en) | Method for rapid generation of external boundary line of continental shelf based on formula lines and limit lines | |
| Lin | Long live China's boom | |
| CN112767549B (en) | Contour surface generation method of high-frequency ground wave radar sea state data | |
| Zhang et al. | A collaborative simplification method for multiple coastlines based on the hierarchical triangulation network partition | |
| Marchuk et al. | Trans-boundary realization of the nested-grid algorithm for trans-pacific and regional tsunami modeling | |
| Lee et al. | Construction of Tidal Datums Based on Ellipsoid Using Spatial Interpolation | |
| CN103927432A (en) | Constrained spatial clustering method for facility location programming | |
| Sultan et al. | Preview on the demarcation process of the maritime border between Iraq and Kuwait by using GIS and satellite image (landsat8) | |
| Hu et al. | The digital generalization principle of digital elevation model | |
| Kamal | Inland electronic navigation charts for enhancing the efficiency of navigational waterway in the Nile River Case Study-El-Wasta Reach | |
| Xie et al. | Method for Delineating the Formula Limit of the Continental Shelf under the Maximum Area Principle Constraint |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| EXSB | Decision made by sipo to initiate substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20171229 Termination date: 20190319 |