CN114387120A - Euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data - Google Patents

Euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data Download PDF

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CN114387120A
CN114387120A CN202210033422.3A CN202210033422A CN114387120A CN 114387120 A CN114387120 A CN 114387120A CN 202210033422 A CN202210033422 A CN 202210033422A CN 114387120 A CN114387120 A CN 114387120A
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张衡
商宸
韩海斌
杨超
蒋沛雯
苏冰
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Shanghai Ocean University
East China Sea Fishery Research Institute Chinese Academy of Fishery Sciences
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East China Sea Fishery Research Institute Chinese Academy of Fishery Sciences
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Abstract

The invention discloses a method for finely identifying the pumping ship state of euphausia superba based on ship position monitoring data, which specifically comprises the following steps: (1) passing VSM or AIS data for the state of each ship site in the ship operation season; (2) when the difference between the navigational speed and the course is within the threshold range, the device is in an operation state; (3) correcting the state points by adopting a neighborhood steady state division method, wherein in ship points in a time sequence, in a short unit time, the front and back of a point i are the same in a short unit time; (4) wherein C isfrontAt a time earlier than point i, CbackThe state is later than the point i time. According to the method, the ship position track data of the euphausia superba pumping continuous fishing ship is utilized, and the state of the fishing ship is judged according to the navigational speed threshold and the direction angle, so that the operation rule of the euphausia superba pumping continuous fishing ship can be accurately known, and reference is provided for future euphausia superba fishing operation.

Description

Euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data
Technical Field
The invention relates to the technical field of ship position data statistical analysis and application of Euphausia superba pumping continuous fishing ship position data, in particular to a method for extracting and pumping continuous fishing ship operation states in real time through ship position data.
Background
The ship Monitoring System (VMS), the automatic ship identification System (AIS) and the ocean Monitoring platform can provide real-time longitude and latitude, course, speed and other information of the fishing ship, and have the characteristics of sufficient data source, high information accuracy and the like. Through carrying out the analysis to the ship position data, can accurately judge the operation and the non-operation state of krill pump suction continuous fishing ship. At present, existing research at home and abroad mainly aims at trawling and gill nets, and mainly focuses on analyzing the ship position states of conventional trawling and gill net fishing boats by using VMS (virtual machine system) data, but a state recognition method of a fishing boat for Antarctic krill is not reported yet. The euphausia superba pump-pumping continuous fishing boat has distinct operation characteristics, and is different from a common trawler which needs to be fished in 1-5 hours, the euphausia superba pump-pumping continuous fishing boat can continuously operate for several days, the change of the speed in the operation process is small, the change of the course difference is large, the wind wave resistance is high, and the influence of wind waves is hardly generated during operation, so that the conventional research method is not suitable for researching the ship position data of the euphausia superba pump-pumping continuous fishing boat.
Under the large background of intense competition of international krill fishery, a novel operation mode for fishing krill by a pumping continuous fishing boat is newly created in the krill fishing strong country such as Norway, and only 1 'dark blue' pumping continuous fishing boat in China just launches without trying to practice shrimp catching, so that how to finely identify and master the novel pumping continuous fishing krill operation mode and a corresponding operation fishery become one of technical bottlenecks which restrict the development of the krill fishery in China. Therefore, an appropriate method for judging the fine operation characteristics of the continuous fishing boat pumped by the antarctic krill and the state of the fishing boat needs to be constructed.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides a fine identification method for the state of a continuous fishing ship pumped by antarctic krill based on real-time ship position data.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data comprises the following steps:
(1) the states of all ship points are comprehensively judged through VSM or AIS data in the ship operation season, and the operation characteristics of the continuous fishing ship pumped by the antarctic krill are shown in a judgment formula (1):
Figure BDA0003467392980000021
(2) when the difference between the navigational speed and the course is within the threshold value range, the ship is in an operation state, wherein C is the state of the ship position point, wherein 0 is fishing operation, 1 is fluctuation attitude adjustment, 2 is high-speed navigation, V is the current navigational speed, d is the current course difference, and V is the current course differenceminFor a set minimum value of the navigational speed, V, of the fishing operation statemidFor a set maximum value of the navigational speed, V, of the fishing operation statemaxAdjusting the maximum speed for a set fluctuating attitude, DminFor a set operating state course difference minimum value of-350 DEG, DmidThe set minimum value of course difference in the non-operation state is-60 DEG DmaxThe maximum value of the course difference is 340 degrees in the set operation state;
(3) and (3) correcting the state points by adopting a neighboring steady state division method, specifically, in the ship position points in the time sequence, in a shorter unit time, in the same shorter unit time before and after the point i, the number of certain ship position state points is more, and then:
Figure BDA0003467392980000031
(4) wherein C isfrontAt a time earlier than point i, CbackIs later than the point i timeStatus.
Further, the AIS data comprises time, position, ship speed and heading.
Further, the fishing operation in the step (2) is that v is more than or equal to 0.8 section and less than 2.5 sections and d is more than or equal to-350 degrees and less than or equal to 340 degrees.
Further, the fluctuation posture in the step (2) is adjusted to be v which is more than or equal to 2.5 sections and less than or equal to 4.7 sections, and d which is more than or equal to-350 degrees and less than or equal to 340 degrees.
Further, v is more than or equal to 4.7 sections and d is more than or equal to-60 degrees and less than or equal to 340 degrees in the high-speed sailing behavior in the step (2).
Further, state C earlier than point i timefrontFrom state (P)1，P2，P3…Pi-1) The value of the middle distance point i with the shortest time interval and the most state is determined, and the state C is later than the time of the point ibackFrom state (P)i+1，Pi+2，Pi+3…Pn) And determining the value with the shortest time interval and the most states at the intermediate distance point i.
Further, the maximum value and the minimum value of the heading difference in the fishing operation state are obtained according to the operation characteristics and the historical experience of the pumping ship of the antarctic krill and time interval analysis of VMS data of the annual ocean platform of a plurality of ships.
Further, the maximum value of the heading difference of the working state is 340 degrees, the median value of the heading difference is-60 degrees, and the minimum value of the heading difference is-350 degrees.
Further, the set minimum value and the set maximum value of the navigational speed are obtained according to a two-month course navigational speed chart of the pumping ship and annual statistical data analysis of a plurality of ships.
Further, during the fishing season, points were removed where the boat speed was 0 or undetected, and during the working period, the boat speed minimum was 0.1 knots and the boat speed maximum was 14.4 knots.
Has the advantages that:
above-mentioned technical scheme has filled the blank that krill pump suction was catched boats and ships state and is judged in succession, compares with prior art, has following advantage and positive effect: according to the method, the comprehensive judgment is carried out on each ship position point state through the real-time ship position data characteristics (position, speed and course difference) in combination with the operation characteristics of the euphausia superba pumping continuous fishing ship, so that the refined operation state of the euphausia superba pumping continuous fishing ship can be extracted based on a ship position data mining method.
Drawings
FIG. 1 is a chart showing the speed course of a continuous fishing vessel pumping Antarctic Endurance krill in Norway at 14:35 on 6/22/2021-19: 09 on 7/17/2021.
Fig. 2 is a graph of the number percentage of boat positions in 6-7 months of a continuous fishing boat pumped by a plurality of krills in 2021 as a function of speed.
Fig. 3 is a state diagram of a state division and state correction adopted by the continuous fishing vessel pumping by Antarctic Endurance krill in Norway.
Detailed Description
The embodiments of the present invention will be described in detail below with reference to the accompanying drawings: the present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.
Example 1:
the embodiment of the invention relates to a method for finely identifying the state of a euphausia superba pumping continuous fishing ship based on real-time ship position data, wherein the state of each ship position is judged by the combination of speed and course difference, and is corrected by a neighborhood state division method, and the method comprises the following steps: (1) judging the speed and course difference threshold of the fishing state according to the speed change frequency change rate; (2) the state of each ship site is judged by combining the navigational speed and the course difference, and is judged by the formula (1), and when the navigational speed and the course are within the threshold range, the ship is in a fishing state; (3) and (3) correcting the state points divided in the step (2) by using a neighboring steady state division method.
Figure BDA0003467392980000051
The midpoint C in the formula (1) is the state of a ship position point, wherein the state 0 is fishing operation, the state 1 is fluctuation attitude adjustment, and the state 2 is high-speed sailing.
The heading of the euphausia superba pumping continuous fishing boat is a horizontal included angle between a north-seeking direction line of the center and a target direction line along the clockwise direction, wherein the fishing boat position is used as the center on the horizontal plane, and the heading value is 0-360 degrees. In order to further analyze the actual change condition of the course, the difference value calculation is carried out on the course angle to obtain the course difference, the course difference is the difference value between the course of two adjacent times and the course of the last time, the positive value reflects the clockwise rotation of the course, and the negative value reflects the anticlockwise rotation of the course of the fishing boat. The time interval of VMS data actually received by the far fishing platform is longer, and the course change is larger.
By taking yearly statistics for a number of vessels, points where the speed of the vessel is 0 or undetected, i.e. points where the actual speed of the vessel is undetected, such as the speed of the vessel and the flow velocity of the ocean current, are removed during the fishing season. And secondly, in the operation period, the minimum value of the ship speed is set as the minimum value of the ship speed, and the maximum value of the ship speed is set as the maximum value of the ship speed.
In order to improve the accuracy of judging the state of the ship position point, a neighboring steady state division method is adopted for correction, and in a shorter unit time and the same shorter unit time before and after the point P, more ship position states exist, so that the ship position state is considered to be in a certain ship position state
Figure BDA0003467392980000061
In the formula (2), the state C earlier than the point ifrontFrom state (P)1，P2，P3…Pi-1) The value of the middle distance point A with the shortest time interval and the most state is determined, and the state C is later than the time of the point ibackFrom state (P)i+1，Pi+2，Pi+3…Pn) And determining the value with the shortest time interval and the most states at the intermediate distance point i.
Judging C by the above formulaiThere are a total of four cases. Cfront、Ci、CbackIf the three states are different, the original state value is kept; if CbackThe number of ship position states is more than CfrontNumber of ship site states, and CiAnd CbackThe state is the same, then CiIs CbackA state; if CfrontThe number of ship position states is more than CbackShip positionNumber of dot states, and CiAnd CbackIf the states are the same, Ci is CfrontA state; if CfrontThe number of the ship position point states is equal to CbackNumber of ship site states, and Ci、Cback、CfrontThe state is the same, then CiIs CbackOr CfrontStatus.
Example 2:
1. determination of Dmin、DmidAnd Dmax
In 2021 Antarctic Endurance Euphausia superba pumping continuous fishing vessel, MMSI: 257400000 (hereinafter referred to as anti reduce) boat position, 255 points from 22/6/2021 to 16/7/2021, 23/41 were selected as samples for analysis. During the period, the ship position points can be divided into 7 sections according to the speed, as shown in fig. 1, the fishing operation in the state 0 (the section C, the section E and the section G) and the fluctuation posture adjustment in the state 1 (the section B, the section D and the section F) are carried out, and the high-speed navigation in the state 2 (the section A) is carried out, namely 3 states. The A section of krill pump-pumping continuous fishing boat sails to a designated fishing ground at a high speed; the section B is to adjust the posture of the ship to be caught in a designated fishing ground; the section C is used for fishing when the ship arrives at the fishing ground 1; the D section is that the operation of the fishing ground 1 is finished, and the fluctuation posture is adjusted and moved to the fishing ground 2; the section E is used for fishing operation when the ship arrives at a fishing ground 2; the F section is the end of the operation of the fishing ground 2, and the fluctuation posture is adjusted and moved to the fishing ground 3; and the G section is used for fishing operation when the ship arrives at the fishing ground 3. The operation of the euphausia superba pumping continuous fishing boat has obvious characteristics, different from the operation that the net is required to be collected every several hours of a common fishing boat, the euphausia superba pumping continuous fishing boat can continuously operate for several days, and the operation time is hardly influenced by wind waves.
The heading of the euphausia superba pumping continuous fishing boat is a horizontal included angle between a north-pointing direction line of the horizontal plane and a target direction line along the clockwise direction by taking the position of the fishing boat as the center, and the heading value is 0-360 degrees. In order to further analyze the actual change condition of the course, the difference value calculation is carried out on the course angle to obtain the course difference, the course difference is the difference value between the course of two adjacent times and the course of the next time and the course of the previous time, and the positive value is oppositeThe negative number reflects the anticlockwise rotation of the course of the fishing boat. The time interval of VMS data actually received by the far fishing platform is longer, the course change is larger, and the course difference D of the operation state is set by referring to the statistics of figure 1 and data of a plurality of shipsmax、DmidAnd Dmin340 deg., -60 deg. and-350 deg., respectively.
2. Determining Vmin、VmidAnd Vmax
The number of boat positions during the 2020 fishing season was recorded as a function of speed, and fig. 2 is a statistical plot of Antarctic end, Saga Sea and Antarctic Sea point speeds (from VMS data) of the Antarctic krill pumping successive fishing boats as a percentage of the total boat position during the fishing season. Since the time interval of the VMS data actually received is long and part of the data is equal to the local flow velocity, the values of 0m/s and Null data are generated, and this part of the data cannot be used as the set V in the judgment of the state of the fishing boatmin、VmidAnd VmaxThe value of (c), is left off.
The euphausia superba pump-pumping continuous fishing boat mainly sails at a low speed during operation, the fishing operation speed is 0.8-2.5 knots, and as can be seen from the figure, the data of the euphausia superba pump-pumping boat are mainly concentrated on 0-2.5 knots, so that the boat speed is 0 or a point which is not detected is removed during the fishing season, the minimum value of the boat speed is 0.1kn/h and the maximum value of the boat speed is 14.4kn/h and the maximum value of the boat speed is the maximum value of the boat speed during the operation period.
3. Euphausia superba pumping continuous fishing vessel state correction
In order to improve the accuracy of judging the state of the ship position point, a neighboring steady state division method is adopted for correction, and in a shorter unit time and the same shorter unit time before and after the point P, more ship position states exist, so that the ship position state is considered to be in a certain ship position state
Figure BDA0003467392980000091
State C earlier than point i timefrontFrom state (P)1，P2，P3…Pi-1) The time interval of the middle distance point i is shortest,The most significant value of the state determines the state C later than the time of point ibackFrom state (P)i+1，Pi+2，Pi+3…Pn) And determining the value with the shortest time interval and the most states at the intermediate distance point i.
The method can better divide the intermediate point of two adjacent states, judge the starting and stopping points of three states of fishing operation, fluctuation attitude adjustment and high-speed sailing, and further realize more accurate fishing vessel state division, and fig. 3 is a state diagram of a continuous fishing vessel pumped by Antarctic Endurance krill in Norway after state division and state correction.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. A euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data is characterized by comprising the following steps:
(1) the states of all ship points are comprehensively judged through VSM or AIS data in the ship operation season, and the operation characteristics of the continuous fishing ship pumped by the antarctic krill are shown in a judgment formula (1):
Figure FDA0003467392970000011
(2) when the difference between the navigational speed and the course is within the threshold value range, the ship is in an operation state, wherein C is the state of the ship position point, wherein 0 is fishing operation, 1 is fluctuation attitude adjustment, 2 is high-speed navigation, V is the current navigational speed, d is the current course difference, and V is the current course differenceminFor a set minimum value of the navigational speed, V, of the fishing operation statemidFor maximum value of speed of fishing operation state，VmaxAdjusting the maximum speed for a set fluctuating attitude, DminFor a set operating state course difference minimum value of-350 DEG, DmidThe set minimum value of course difference in the non-operation state is-60 DEG DmaxThe maximum value of the course difference is 340 degrees in the set operation state;
(3) and (3) correcting the state points by adopting a neighboring steady state division method, specifically, in the ship position points in the time sequence, in a shorter unit time, in the same shorter unit time before and after the point i, the number of certain ship position state points is more, and then:
Figure FDA0003467392970000012
(4) wherein C isfrontAt a time earlier than point i, CbackThe state is later than the point i time.
2. The method for finely identifying the state of the Antarctic krill pumping continuous fishing vessel based on real-time ship position data according to claim 1, wherein the AIS data comprises time, position, ship speed and heading.
3. The method for finely identifying the state of the Euphausia superba pumping continuous catching ship based on real-time ship position data is characterized in that the catching operation in the step (2) is 0.8 knots v < 2.5 knots, -350 DEG and d < 340 deg.
4. The method for finely identifying the state of the Euphausia superba pumping continuous catching ship based on the real-time ship position data is characterized in that the fluctuation posture in the step (2) is adjusted to be 2.5 knots v < 4.7 knots, -350 DEG d < 340 deg.
5. The method for finely identifying the state of the Euphausia superba pumping continuous catching ship based on the real-time ship position data is characterized in that the high-speed sailing behavior in the step (2) is 4.7 knots v-60 degrees d-340 degrees.
6. The method for finely identifying the state of the Euphausia superba pumping continuous catching ship based on real-time ship position data as claimed in claim 1, wherein the state C is earlier than the time of point ifrontFrom state (P)1，P2，P3…Pi-1) The value of the middle distance point i with the shortest time interval and the most state is determined, and the state C is later than the time of the point ibackFrom state (P)i+1，Pi+2，Pi+3…Pn) And determining the value with the shortest time interval and the most states at the intermediate distance point i.
7. The method for finely identifying the states of the Euphausia superba pumping continuous fishing vessel based on real-time vessel position data is characterized in that the maximum value and the minimum value of the heading difference of the fishing operation states are obtained according to the characteristics, the historical experience and the VMS data time interval analysis of the annual ocean platform of the Euphausia superba pumping vessel.
8. The method for finely identifying the state of the Antarctic krill pumping continuous fishing vessel based on the real-time ship position data is characterized in that the maximum value of the heading difference of the working state is 340 degrees, the median value of the heading difference is-60 degrees, and the minimum value is-350 degrees.
9. The method for finely identifying the state of the Euphausia superba pumping continuous catching ship based on the real-time ship position data is characterized in that the set minimum value and maximum value of the navigational speed are obtained according to a two-month heading navigational speed chart of the pumping ship and the annual statistical data analysis of a plurality of ships.
10. The method for finely identifying the state of the Euphausia superba pumping continuous fishing vessel based on real-time ship position data is characterized in that points with the ship speed of 0 or undetected are removed during the fishing season, and the minimum value of the ship speed is 0.1 knots and the maximum value of the ship speed is 14.4 knots during the working period.
CN202210033422.3A 2022-01-12 2022-01-12 Euphausia superba pumping continuous fishing ship state fine identification method based on real-time ship position data Pending CN114387120A (en)

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