Ship wind resistance determination method and device, electronic equipment and readable storage medium

Abstract

The application provides a ship wind resistance determination method and device, electronic equipment and a readable storage medium, relates to the ship wind resistance prediction technical field, and aims to solve or improve the technical problem that the method for obtaining wind resistance by using a traditional sensor cannot be applied to the detection of the wind resistance of each ship in the global range in the prior art. The determination method comprises the following steps: obtaining AIS information of a ship; determining the maximum draft of the ship based on the AIS information; determining the upper deck height of the ship based on the maximum draft of the ship and the ship height of the ship; determining the current draft of the ship based on the AIS information; determining the height above the water surface of the ship based on the maximum draft, the upper deck height and the current draft; obtaining the included angle between the wind direction and the width direction of the ship; determining the actual wind receiving area of the ship based on the height above the water surface, the ship length of the ship, the ship width of the ship and the included angle between the wind direction and the width direction of the ship; obtaining the wind speed; and determining the wind resistance of the ship based on the actual wind receiving area and the wind speed.

Description

Technical Field

[0001] This invention relates to the field of ship wind resistance prediction technology, and more specifically, to a method, apparatus, electronic device, and readable storage medium for determining ship wind resistance. Background Technology

[0002] In related technologies, when measuring ship wind resistance, data such as the ship's current wind resistance can usually only be obtained through traditional sensors. However, these sensors are not required to be installed on every ship. Therefore, it is impossible to dynamically estimate the current wind resistance of millions of ships worldwide.

[0003] Therefore, in order to estimate ship wind resistance globally, inventing a method for determining ship wind resistance is a pressing technical problem that needs to be solved. Summary of the Invention

[0004] The present invention aims to solve or improve the technical problem that the traditional sensor method for obtaining wind resistance in the prior art cannot be applied to the wind resistance detection of every ship in the world.

[0005] The first aspect of the present invention is to provide a method for determining the wind resistance of a ship.

[0006] A second aspect of the present invention is to provide a device for determining ship wind resistance.

[0007] A third aspect of the present invention is to provide an electronic device.

[0008] A fourth aspect of the present invention is to provide a readable storage medium.

[0009] The method for determining ship wind resistance provided by this invention includes: acquiring the ship's AIS (Automatic-identification-System) information; determining the ship's maximum draft based on the AIS information; determining the ship's upper deck height based on the ship's maximum draft and ship height; determining the ship's current draft based on the AIS information; determining the ship's height above water based on the maximum draft, upper deck height, and current draft; acquiring the angle between the wind direction and the ship's width direction; inputting the ship's length, beam, and hull type into a first prediction model to predict the ship's block coefficient; determining the ship's actual windward area based on the ship's height above water, length, beam, angle between the wind direction and width direction, and block coefficient; acquiring the wind speed; and determining the ship's wind resistance based on the actual windward area and wind speed.

[0010] The method for determining ship wind resistance provided by this invention includes: acquiring the ship's AIS information; wherein the AIS information includes MMSI (Maritime-Mobile-Service-Identity), ship's longitude, ship's latitude, ship's length, ship's beam, etc.; determining the ship's maximum draft based on the AIS information; wherein the maximum draft is also the maximum depth the ship can penetrate below the water surface; determining the ship's upper deck height based on the ship's maximum draft and ship's height; the upper deck height is also the minimum height above the water surface when the ship is at its deepest position, i.e., upper deck height + maximum draft = ship's height; determining the ship's current draft based on the AIS information; wherein the current draft is also the current depth the ship can penetrate below the water surface; determining the ship's wind resistance based on the maximum draft, upper deck height, and current draft. The height above the waterline is determined by the ship's current height above the water. After determining this height, the angle between the wind direction and the ship's width is calculated. Then, the ship's length, width, and hull shape are input into the first prediction model to predict the ship's block coefficient. This step considers that the actual area of ​​a ship is not rectangular but slightly smaller than a rectangle, hence the introduction of the block coefficient concept. This further ensures that the calculated windward area approximates the ship's actual windward area. Based on the height above the waterline, the ship's length, width, the angle between the wind direction and the ship's width, and the block coefficient, the ship's actual windward area is determined. The ship's length is the length along the direction of navigation, and the width is the length perpendicular to the direction of navigation. After determining the actual windward area, the wind speed is obtained. Finally, the ship's wind resistance is determined based on the actual windward area and wind speed. The method of this invention combines the mandatory installation feature of AIS equipment, and its data has the advantage of wide coverage, which can more efficiently determine the wind resistance of ships and calculate the wind resistance of every ship in the sea area, providing strong data support for ship monitoring.

[0011] In some technical solutions, optionally, the block coefficient of the vessel includes a front block coefficient and a side block coefficient. The step of determining the actual windward area of ​​the vessel based on the vessel's height above water, length, beam, angle between the wind direction and the beam direction, and the block coefficient specifically includes: determining the windward area of ​​the vessel's front based on the height above water, beam, front block coefficient, and angle between the wind direction and the beam direction; determining the windward area of ​​the vessel's sides based on the height above water, length, side block coefficient, and angle between the wind direction and the beam direction; and determining the actual windward area of ​​the vessel based on the windward areas of the front and sides.

[0012] In this technical solution, when determining the actual windward area of ​​a ship, the windward area of ​​the ship's front is first determined based on the height above the waterline, the ship's width, the frontal block coefficient, and the angle between the wind direction and the ship's width direction. Then, the windward area of ​​the ship's sides is determined based on the height above the waterline, the ship's length, the side block coefficient, and the angle between the wind direction and the ship's width direction. It is understandable that during actual ship operation, the wind direction is not directly facing the ship's front or side, but forms a certain angle with the ship's front, that is, with the ship's width direction. In the calculation process, the wind in this direction can be decomposed into two directions: wind perpendicular to the ship's front and wind perpendicular to the ship's side. Multiplying the two decomposed directions by the front area and the side area of ​​the ship respectively yields the actual windward area of ​​the ship, thereby improving the accuracy of the calculation. During navigation, the side facing forward along the navigation direction is the front, the side facing backward along the navigation direction is the stern, and the side is the side.

[0013] In some technical solutions, optionally, the height above the waterline, the ship's beam, the block coefficient of the front, the angle between the wind direction and the ship's beam direction, and the windward area of ​​the ship's front satisfy the following relationship: Windward area of ​​the ship's front = Height above the waterline × ship beam × Front square coefficient × cos(the angle between the wind direction and the ship's width); the height above the waterline, the ship's length, the block coefficient, the angle between the wind direction and the ship's width, and the windward area of ​​the ship's sides satisfy the following relationship: Windward area of ​​the ship's sides = Height above the waterline × Ship's captain × Side square coefficient × sin(the angle between the wind direction and the width direction of the ship); where cos is the cosine function and sin is the sine function.

[0014] In this technical solution, the windward area of ​​the front of the ship and the windward area of ​​the side of the ship can be determined according to the above relationship, and then the actual windward area of ​​the ship can be determined. The actual windward area of ​​the ship is the sum of the windward area of ​​the front of the ship and the windward area of ​​the side of the ship. In this way, the wind resistance of the ship can be determined based on the actual windward area of ​​the ship.

[0015] In some technical solutions, optionally, the AIS information includes MMSI information. The steps for determining the maximum draft of a vessel based on the AIS information specifically include: obtaining the vessel's registration file information based on the MMSI information; determining whether the registration file information includes the vessel's maximum draft; determining the vessel's maximum draft when the registration file information includes the vessel's maximum draft; and extracting the vessel's first feature information from the vessel's AIS information when the registration file information does not include the vessel's maximum draft, inputting the first feature information into a second prediction model, and simulating and predicting the vessel's maximum draft through the second prediction model.

[0016] In this technical solution, when determining the maximum draft of a vessel, the system first checks if the vessel's maximum draft is included in the registration file. If it is, the maximum draft can be directly extracted from the registration file. If it is not, the system extracts the vessel's first feature information from its AIS information, inputs this first feature information into a second prediction model, and uses the second prediction model to simulate and predict the vessel's maximum draft. The first feature information includes one or more of the following features: length, beam, and hull type. The second prediction model can be a decision tree model.

[0017] In some technical solutions, optionally, the AIS information includes MMSI information. The step of determining the ship's current draft based on the AIS information specifically includes: determining whether the AIS information includes the ship's current draft; if the AIS information includes the ship's current draft, determining the ship's current draft; if the AIS information does not include the ship's current draft, obtaining the ship's registration file information based on the MMSI information, extracting the ship's second feature information from the ship's registration file information, inputting the second feature information into a third prediction model, and simulating and predicting the ship's current draft through the third prediction model.

[0018] In this technical solution, when determining the current draft of a vessel, the system first checks if the AIS information includes the vessel's current draft. If it does, the current draft can be directly extracted from the AIS information. If it doesn't, the system extracts the vessel's second characteristic information from its registration file. This second characteristic information is then input into a third prediction model, which predicts the vessel's current draft. The second characteristic information includes one or more of the following: historical berthing frequency, sailing duration, sailing speed, berthing time, waiting time, average berthing rate at the target berth, standard deviation of the berthing rate at the target berth, kurtosis of the berthing rate at the target berth, and skewness of the berthing rate at the target berth. Understandably, the current draft is affected by the loading status, and this second characteristic information is used to determine the loading status. Furthermore, since some vessels call at temporary berths only for refueling or crew changes, without affecting the current draft, the target berths here can also be understood as berths with certain attributes, or as non-temporary berths. The berthing duration affects the loading capacity; the longer the operation time, the more cargo can be loaded. Therefore, if the current draft cannot be obtained from AIS information, this invention can predict the current draft based on these second feature information using a third prediction model. Optionally, the third prediction model can be an Ada-boost (an iterative algorithm) model.

[0019] In some technical solutions, optionally, in the step of determining the ship's wind resistance based on the actual wind-receiving area and wind speed, the actual wind-receiving area, wind speed, and wind resistance satisfy the following relationship: Wind resistance = 0.5 × air density × Actual wind-receiving area × drag coefficient × wind speed × Wind speed.

[0020] In this technical solution, once the actual windward area and wind speed of the ship are obtained, the ship's wind resistance can be calculated using this formula. The air density and drag coefficient are estimated constants.

[0021] A second aspect of the present invention provides a ship wind resistance determination device, comprising: an information acquisition module for acquiring AIS information of a ship; a determination module for determining the maximum draft of the ship based on the AIS information; the determination module is further configured to determine the upper deck height of the ship based on the maximum draft and the ship's height; the determination module is further configured to determine the current draft of the ship based on the AIS information; the determination module is further configured to determine the height above the waterline of the ship based on the maximum draft, the upper deck height, and the current draft; the information acquisition module is further configured to acquire the angle between the wind direction and the ship's width direction; the determination module is further configured to input the ship's length, the ship's width, and the ship's hull type into a first prediction model to predict the ship's block coefficient; the determination module is further configured to determine the actual windward area of ​​the ship based on the height above the waterline, the ship's length, the ship's width, the angle between the wind direction and the ship's width direction, and the ship's block coefficient; the information acquisition module is further configured to acquire the wind speed; and the determination module is further configured to determine the ship's wind resistance based on the actual windward area and the wind speed.

[0022] A third aspect of the present invention provides an electronic device, including a memory and a processor, wherein the memory stores a computer program or instructions, and the processor executes the computer program or instructions to implement the ship wind resistance determination method provided by any of the technical solutions of the first aspect of this application.

[0023] The fourth aspect of the present invention provides a readable storage medium storing a program or instructions, wherein when a processor executes the program or instructions, it implements the ship wind resistance determination method provided by any of the technical solutions of the first aspect of this application.

[0024] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0025] The above and / or additional aspects and advantages of embodiments of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, wherein:

[0026] Figure 1 One of the flowcharts of the ship wind resistance determination method provided by an embodiment of the present invention is shown;

[0027] Figure 2 A second schematic flowchart of the ship wind resistance determination method provided by an embodiment of the present invention is shown;

[0028] Figure 3 A block diagram of a ship wind resistance determination device provided in an embodiment of the present invention is shown;

[0029] Figure 4 A block diagram of an electronic device provided by an embodiment of the present invention is shown;

[0030] Figure 5 A schematic diagram illustrating the calculation principle of the square coefficient in this embodiment of the invention;

[0031] Figure 6 A schematic structural diagram of a ship for implementing embodiments of the present invention. Detailed Implementation

[0032] To better understand the above aspects, features, and advantages of the embodiments of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0033] Numerous specific details are set forth in the following description in order to provide a full understanding of embodiments of the invention. However, embodiments of the invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of embodiments of the invention is not limited to the specific embodiments disclosed below.

[0034] like Figure 1 As shown, the method for determining ship wind resistance provided by the present invention includes the following steps:

[0035] S102: Obtain the vessel's AIS information;

[0036] S104: Determine the maximum draft of the vessel based on AIS information;

[0037] S106: Determine the height of the upper deck of a ship based on its maximum draft and height.

[0038] S108: Determine the ship's current draft based on AIS information;

[0039] S110: Determine the ship's height above waterline based on maximum draft, upper deck height, and current draft;

[0040] S112: Obtain the angle between the wind direction and the width direction of the ship, input the ship's length, ship's width and ship type into the first prediction model, and predict the ship's block coefficient.

[0041] S114: The actual windward area of ​​a ship is determined based on its height above waterline, length, beam, the angle between the wind direction and the beam direction, and the block coefficient.

[0042] S116: Obtain wind speed and determine the ship's wind resistance based on the actual windward area and wind speed.

[0043] The method for determining ship wind resistance provided by this invention includes: acquiring the ship's AIS information; wherein the AIS information includes MMSI, ship's longitude, ship's latitude, ship's length, ship's beam, etc.; determining the ship's maximum draft based on the AIS information; wherein the maximum draft is also the maximum depth the ship can penetrate below the water surface; determining the ship's upper deck height based on the ship's maximum draft and ship's height; the upper deck height is also the minimum height the ship can float above the water surface, i.e., upper deck height + maximum draft = ship's height; determining the ship's current draft based on the AIS information; wherein the current draft is also the current depth the ship can penetrate below the water surface; determining the ship's height above the water surface based on the maximum draft, upper deck height, and current draft; wherein the water... The height above the waterline, i.e., the current height of the vessel above the water, is determined by obtaining the angle between the wind direction and the vessel's width direction. Then, the vessel's length, beam, and hull type are input into the first prediction model to predict the vessel's block coefficient. This step considers that the actual area of ​​a vessel is not a standard rectangle, but slightly smaller. Therefore, the concept of a block coefficient is introduced to further approximate the calculated windward area of ​​the vessel. Based on the vessel's height above the waterline, length, beam, angle between the wind direction and the vessel's width direction, and block coefficient, the actual windward area of ​​the vessel is determined. After determining the actual windward area, the wind speed is obtained. Based on the actual windward area and wind speed, the vessel's wind resistance is determined. This invention's method, combined with the mandatory installation of AIS equipment, offers the advantage of wide data coverage and more frequent determination of the wind resistance experienced by vessels. It can calculate the wind resistance of every vessel in the sea area, providing strong data support for vessel monitoring.

[0044] In some embodiments, optionally, the block factor of the vessel includes a front block factor and a side block factor. The step of determining the actual windward area of ​​the vessel based on the vessel's height above water, the vessel's length, the vessel's beam, the angle between the wind direction and the vessel's beam direction, and the vessel's block factor specifically includes: determining the windward area of ​​the vessel's front based on the height above water, the vessel's beam, the front block factor, and the angle between the wind direction and the vessel's beam direction; wherein the front of the vessel is the surface formed by the vessel's beam and the vessel's height; determining the windward area of ​​the vessel's sides based on the height above water, the vessel's length, the side block factor, and the angle between the wind direction and the vessel's beam direction; wherein the sides of the vessel are the surface formed by the vessel's length and the vessel's height; and determining the actual windward area of ​​the vessel based on the windward area of ​​the vessel's front and the windward area of ​​the vessel's sides.

[0045] In this embodiment, when determining the actual windward area of ​​the ship, the windward area of ​​the front of the ship is first determined based on the height above the water surface, the ship's width, the frontal block coefficient, and the angle between the wind direction and the width direction of the ship. Then, the windward area of ​​the side of the ship is determined based on the height above the water surface, the ship's length, the side block coefficient, and the angle between the wind direction and the width direction of the ship.

[0046] Understandably, during actual ship operation, the wind direction is not directly facing the front or side of the ship, but rather forms an angle with the front, or an angle with the width of the ship. In the calculation process, this wind direction can be decomposed into two directions: wind perpendicular to the front and wind perpendicular to the side. Multiplying these two directions by the front and side areas of the ship respectively yields the actual wind-receiving area of ​​the ship, thus improving the accuracy of the calculation.

[0047] The concept of the square coefficient of the present invention will be described in further detail below:

[0048] Considering that the actual area of ​​a ship is not rectangular, but slightly smaller than a rectangle, the concept of a square coefficient is introduced, such as... Figure 5 As shown, the block coefficient refers to the ratio of the volume of the ship's hull below the waterline (▽) to the volume of the cuboid formed by the ship's length (L), beam (B), and draft (d). The size of the block coefficient indicates the plumpness or slenderness of the volume below the waterline. A larger block coefficient indicates that the ship appears fuller and closer to a rectangle, while a smaller block coefficient indicates that the ship appears slimmer. Since the actual shape of a ship is not rectangular but slightly smaller than a rectangle, the concept of the block coefficient is introduced to further approximate the calculated windward area of ​​the ship.

[0049] Among them, such as Figure 6 As shown, points a, b, c, d, e, f, g, and h are the vertices of the ship. Let side cd be the front of the ship, side ae be the side of the ship, the width of the ship be the length of ab, and the length of the ship be the length of cg.

[0050] Frontal squareness coefficient = Actual area of ​​the frontal section above waterline / (ship beam) × (Height above water surface);

[0051] The actual area of ​​the frontal cross-section above the waterline is the area of ​​the cross-section above the waterline obtained by cutting the ship vertically downwards along side cd, where the ship's width is ab. × The height above the waterline represents the ideal frontal wind-receiving area. Therefore, the larger the frontal squareness coefficient, the closer cd is to ab, indicating a more robust ship. Conversely, the smaller the frontal squareness coefficient, the smaller cd is, indicating a more slender ship.

[0052] Similarly, the side squareness coefficient = actual area of ​​the side section above the waterline / (ship length) × (Height above water surface);

[0053] The actual area of ​​the side section above the waterline is the area of ​​the section above the waterline obtained by cutting the ship vertically downwards along side ae, where the ship length is cg. × The height above the waterline represents the ideal side wind-receiving area. Therefore, the larger the side block coefficient, the closer ae is to cg, indicating a more robust ship. Conversely, the smaller the side block coefficient, the smaller ae is, indicating a more slender ship.

[0054] It is generally believed that the block coefficient is a constant for the same ship and is related to the ship's "width" or "height". However, for different ships, a decision tree model can be built in advance to link factors such as ship type, length, width and block coefficient. In this way, the block coefficient of different ship types can be calculated on the ground with the ship type, length and width as input, thus optimizing the ship's windward area and improving the accuracy of the calculation.

[0055] In some embodiments, optionally, the height above water, the ship's beam, the block coefficient of the facade, the angle between the wind direction and the ship's beam direction, and the windward area of ​​the ship's facade satisfy the following relationship: Windward area of ​​the ship's facade = Height above water × ship beam × Front square coefficient × cos(the angle between the wind direction and the ship's width); the height above the waterline, the ship's length, the block coefficient, the angle between the wind direction and the ship's width, and the windward area of ​​the ship's sides satisfy the following relationship: Windward area of ​​the ship's sides = Height above the waterline × Ship's captain × Side square coefficient × sin (the angle between the wind direction and the width direction of the ship).

[0056] In this embodiment, the windward area of ​​the front of the ship and the windward area of ​​the side of the ship can be determined according to the above relationship, and then the actual windward area of ​​the ship can be determined. The actual windward area of ​​the ship is the sum of the windward area of ​​the front of the ship and the windward area of ​​the side of the ship. In this way, the wind resistance of the ship can be determined according to the actual windward area of ​​the ship.

[0057] In some embodiments, optionally, the AIS information includes MMSI information. The step of determining the maximum draft of a vessel based on the AIS information specifically includes: obtaining the vessel's registration file information based on the MMSI information; determining whether the registration file information includes the vessel's maximum draft; if the registration file information includes the vessel's maximum draft, determining the vessel's maximum draft; if the registration file information does not include the vessel's maximum draft, extracting the vessel's first feature information from the vessel's AIS information, inputting the first feature information into a second prediction model, and simulating and predicting the vessel's maximum draft through the second prediction model.

[0058] In this embodiment, when determining the maximum draft of a vessel, the system first checks whether the vessel's maximum draft is included in the registration file information. If the registration file information includes the maximum draft, it can be directly extracted from the registration file information. If the registration file information does not include the maximum draft, the system extracts the vessel's first feature information from its AIS information, inputs this first feature information into a second prediction model, and uses the second prediction model to simulate and predict the vessel's maximum draft. The first feature information includes one or more of the following features: length, beam, and hull type. The second prediction model can be a decision tree model.

[0059] In some embodiments, optionally, the AIS information includes MMSI information. The step of determining the current draft of the vessel based on the AIS information specifically includes: determining whether the current draft of the vessel is included in the AIS information; if the current draft of the vessel is included in the AIS information, determining the current draft of the vessel; if the current draft of the vessel is not included in the AIS information, obtaining the vessel's registration file information based on the MMSI information, extracting the vessel's second feature information from the vessel's registration file information, inputting the second feature information into a third prediction model, and simulating and predicting the current draft of the vessel through the third prediction model.

[0060] In this embodiment, when determining the ship's current draft, the system first checks if the AIS information includes the ship's current draft. If it does, the current draft can be directly extracted from the AIS information. If it doesn't, the system extracts the ship's second characteristic information from its registration file, inputs this second characteristic information into a third prediction model, and then predicts the ship's current draft using the third prediction model. The second characteristic information includes one or more of the following: historical berthing frequency, sailing duration, sailing speed, berthing time, waiting time, average berthing rate at the target berth, standard deviation, kurtosis, and skewness. It's understandable that the current draft is affected by the loading situation, and this second characteristic information is used to determine the loading situation. Furthermore, since some ships call at temporary berths only for refueling or crew changes, which doesn't affect the current draft, the target berth can also be understood as a berth with certain attributes, or a non-temporary berth. The berthing time affects the loading capacity; the longer the operation time, the more cargo is loaded, and the greater the current draft. Therefore, if the current draft cannot be directly obtained from AIS information, this invention can predict the current draft based on these second feature information using a third prediction model. Optionally, the third prediction model can be the Ada-boost model.

[0061] In some embodiments, optionally, in the step of determining the ship's wind resistance based on the actual wind-receiving area and wind speed, the actual wind-receiving area, wind speed, and wind resistance satisfy the following relationship: Wind resistance = 0.5 × air density × actual wind-receiving area × drag coefficient × wind speed × wind speed.

[0062] In this embodiment, once the actual windward area and wind speed of the ship are obtained, the ship's wind resistance can be calculated using this formula. The air density and drag coefficient are estimated constants.

[0063] like Figure 2 As shown, another embodiment of the present invention provides a method for determining ship wind resistance, comprising the following steps:

[0064] S202: Obtain AIS information and use the Douglas-Puk algorithm to thin out the trajectory position;

[0065] The AIS information includes: MMSI, longitude of the ship's track position, latitude of the ship's track position, ship length, ship beam, and current draft;

[0066] By using the Douglas-Puk algorithm to thin out the trajectory positions, the storage size can be reduced and the computational efficiency can be improved.

[0067] S204: Use the clustering segmented trajectory algorithm to determine whether the trajectory position is valid; if yes, proceed to S208; otherwise, proceed to S206.

[0068] S206: Fill in the invalid trajectory locations using Lagrange interpolation;

[0069] S208: Use the length and width scatter matrix region method to determine whether the ship length and width are valid; if yes, then execute S212; otherwise, execute S210.

[0070] S210: Using historical berth attributes, ship speed, and ship type as features, the decision tree method is used to simulate and calculate the ship length and beam.

[0071] S212: Determine if the upper deck height exists in the MMSI information and if the upper deck height is valid; if yes, execute S216; otherwise, execute S214.

[0072] S214: Using ship length, beam, and hull type as features, a decision tree model is used to simulate and calculate the height of the ship's upper deck.

[0073] S216: Determine if the maximum draft exists in the MMSI information; if yes, execute S220; otherwise, execute S218.

[0074] S218: Using ship length, beam, and hull type as features, a decision tree model is used to simulate and calculate the maximum draft;

[0075] S220: Determine if the current draft exists in the AIS information; if yes, execute S224; otherwise, execute S222.

[0076] S222: Using statistical indicators such as the average, standard deviation, kurtosis, and skewness of historical berthing frequency, sailing duration, sailing speed, berthing time, waiting time, and berthing rate of different berth attributes as features, the Ada-boost model is used to simulate and calculate the current draft.

[0077] S224: Calculate the height of the ship above the waterline using the height of the upper deck, maximum draft, and current draft;

[0078] S226: Use the grid of latitude and longitude corresponding to the ship's position to obtain meteorological information, and obtain the wind speed and wind direction in the meteorological values;

[0079] S228: Calculate the cross-sectional area exposed to wind when the wind is directly facing the bow of the ship, and calculate the cross-sectional area exposed to wind when the wind is directly facing the side of the ship;

[0080] S230: Introducing the wind angle parameter, the wind is decomposed into the direction directly facing the ship and the side facing the ship, the actual wind-receiving area of ​​the ship is calculated, and the final wind resistance value is calculated through the wind resistance formula.

[0081] Another embodiment of the present invention provides a method for determining ship wind resistance, comprising the following steps:

[0082] Step 1: Obtain AIS information, which includes: MMSI information, ship's longitude, ship's latitude, ship's length, ship's beam, and current draft;

[0083] Step 2: Use the Douglas-Puk algorithm to thin out the trajectory positions, reducing storage requirements and improving computational efficiency;

[0084] Step 3: Use the clustering segmentation trajectory algorithm to determine the validity of the trajectory point positions, and use the Lagrange interpolation method to fill in the invalid trajectory point positions;

[0085] Step 4: Use the length and width scatter matrix region method to determine the validity of the ship's length and width. For obviously invalid length and width values, use the historical berth attributes, ship speed, and ship type as features, and use the decision tree method to simulate and calculate the length and width values.

[0086] Step 5: Use MMSI information to obtain the ship's upper deck height. If there is no valid upper deck height data, use the ship's length, beam, and type as features and use a decision tree model to simulate and calculate the ship's upper deck height.

[0087] Step 6: Use MMSI information to obtain the maximum draft of the ship. If there is no valid maximum draft data, use the ship length, beam and hull type as features and use a decision tree model to simulate and calculate the maximum draft of the ship.

[0088] Step 7: Use the grid of latitude and longitude corresponding to the ship's position to obtain meteorological information, and extract the wind speed and wind direction from the meteorological values;

[0089] Step 8: Use MMSI information to obtain the current draft. If there is no valid current draft, use statistical indicators such as the average, standard deviation, kurtosis, and skewness of the ship's historical call-in frequency, sailing time, sailing speed, berthing time, waiting time, and call-in rate of different berth attributes as features, and use the Ada-boost model to simulate and calculate the current draft.

[0090] Step Nine: Calculate the ship's height above waterline using the upper deck height, maximum draft, and current draft, using the following formula:

[0091] Height above water = Height of upper deck + Maximum draft - Current draft;

[0092] The formula for calculating the cross-sectional area exposed to wind when it is directly facing the bow of the ship is as follows:

[0093] Windward cross-sectional area = Height above water surface × boat width× Front square coefficient;

[0094] The formula for calculating the cross-sectional area exposed to wind when it is directly facing the side of the ship is as follows:

[0095] Windward cross-sectional area = Height above water surface × captain × Side squareness coefficient;

[0096] Step 10: Introduce the wind angle parameter, decompose the wind into the direction directly facing the ship and the side facing the ship, and calculate the actual wind-receiving area. The formula is as follows:

[0097] Actual wind-receiving area = cross-sectional area of ​​the ship's bow directly exposed to wind × cos(wind angle) + cross-sectional area of ​​the ship's side directly exposed to the wind × sin (wind angle); the wind angle is the angle between the wind direction and the width direction of the ship.

[0098] Step 11: Calculate the final wind resistance value using the wind resistance formula, in Newtons (N). The wind speed is measured in meters per second (m / s). The wind resistance calculation formula is as follows:

[0099] Wind resistance = 0.5 × air density × Actual wind-receiving area × drag coefficient × Ship wind speed × For ship wind speed;

[0100] The values ​​for air density and drag coefficient are estimated constants.

[0101] The beneficial effects of this invention are as follows:

[0102] 1. Combining the mandatory installation of AIS equipment, its data has the advantage of wide coverage and can determine the wind resistance of ships more frequently, providing strong data support for ship monitoring.

[0103] 2. Before inputting data into the model, perform a preliminary judgment and use an algorithm to fill in the gaps to avoid outliers affecting the calculation.

[0104] 3. The stress projection section is modeled differently according to various parameters, which improves the accuracy of the estimation.

[0105] The inventive point of this solution is:

[0106] 1. Remotely simulate and monitor ship wind resistance using AIS spatiotemporal data.

[0107] 2. Before inputting data into the model, perform a preliminary judgment and use an algorithm to fill in the gaps to avoid outliers affecting the calculation.

[0108] like Figure 3 As shown, a second aspect of the present invention provides a ship wind resistance determination device 1, including an information acquisition module 12 and a determination module 14. The information acquisition module 12 is used to acquire the ship's AIS information; the determination module 14 is used to determine the ship's maximum draft based on the AIS information; the determination module 14 is also used to determine the ship's upper deck height based on the ship's maximum draft and ship height; the determination module 14 is also used to determine the ship's current draft based on the AIS information; and the determination module 14 is also used to determine the ship's water surface elevation based on the maximum draft, upper deck height, and current draft. The information acquisition module 12 is also used to acquire the angle between the wind direction and the width direction of the ship; the determination module 14 is also used to input the ship's length, ship's width and ship type into the first prediction model to predict the ship's block coefficient; the determination module 14 is also used to determine the ship's actual windward area based on the height above the water surface, the ship's length, the ship's width, the angle between the wind direction and the width direction of the ship and the ship's block coefficient; the information acquisition module 12 is also used to acquire the wind speed; the determination module 14 is also used to determine the ship's wind resistance based on the ship's actual windward area and wind speed.

[0109] like Figure 4 As shown, the third aspect of the present invention provides an electronic device 700, including a processor 701, a memory 702, and a program or instructions stored in the memory 702 and executable on the processor 701. When the program or instructions are executed by the processor 701, they implement the above-mentioned method for determining ship wind resistance and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0110] A fourth aspect of the present invention provides a readable storage medium storing a program or instructions, wherein a processor executes the program or instructions to implement the ship wind resistance determination method provided in any embodiment of the first aspect of this application.

[0111] In embodiments of the present invention, the terms "first," "second," and "third" are used only for descriptive purposes and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise expressly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in embodiments of the present invention according to the specific circumstances.

[0112] Furthermore, although the operations are described in a specific order, this should be understood as requiring that such operations be performed in a specific order or sequential order, or requiring that all illustrated operations be performed to achieve the desired result. In certain environments, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of the invention. Certain features described in the context of individual embodiments may also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation may also be implemented individually or in any suitable sub-combination in multiple implementations.

[0113] Although the subject matter has been described using language describing specific structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

[0114] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Those skilled in the art will recognize that various modifications and variations are possible with respect to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of the present invention should be included within the protection scope of the embodiments of the present invention.

Claims

1. A method for determining ship wind resistance, characterized in that, include: Obtain the ship's AIS information; Based on the AIS information, the maximum draft of the vessel is determined; The height of the upper deck of the vessel is determined based on the vessel's maximum draft and the vessel's height. Based on the AIS information, the current draft of the vessel is determined; The height of the vessel above the waterline is determined based on the maximum draft, the upper deck height, and the current draft. Obtain the angle between the wind direction and the width direction of the vessel; The ship's length, beam, and hull type are input into the first prediction model to predict the ship's block coefficient. The actual windward area of ​​the vessel is determined based on the vessel's height above the waterline, the vessel's length, the vessel's width, the angle between the wind direction and the vessel's width direction, and the vessel's block coefficient. Get wind speed; The wind resistance of the ship is determined based on the actual wind-receiving area and the wind speed. The AIS information includes MMSI information. The step of determining the maximum draft of the vessel based on the AIS information specifically includes: The vessel's registration file information is obtained based on the MMSI information; Determine whether the registration file information includes the maximum draft of the vessel; When the registration file information includes the maximum draft of the vessel, the maximum draft of the vessel is determined; When the registration file information does not include the maximum draft of the vessel, the first feature information of the vessel is extracted from the vessel's AIS information, the first feature information is input into the second prediction model, and the maximum draft of the vessel is simulated and predicted by the second prediction model. The step of determining the ship's current draft based on the AIS information specifically includes: Determine whether the AIS information includes the ship's current draft; When the AIS information includes the ship's current draft, determine the ship's current draft; When the AIS information does not include the ship's current draft, the ship's registration file information is obtained based on the MMSI information, the ship's second feature information is extracted from the registration file information, the second feature information is input into the third prediction model, and the ship's current draft is simulated and predicted by the third prediction model.

2. The method for determining ship wind resistance according to claim 1, characterized in that, The block factor of the vessel includes the front block factor and the side block factor. The step of determining the actual windward area of ​​the vessel based on the vessel's height above water, the vessel's length, the vessel's beam, the angle between the wind direction and the vessel's beam direction, and the vessel's block factor specifically includes: The windward area of ​​the ship's front is determined based on the height above the water surface, the ship's width, the frontal squareness coefficient, and the angle between the wind direction and the ship's width direction. The windward area of ​​the ship's side is determined based on the height above the water surface, the ship's length, the side block coefficient, and the angle between the wind direction and the ship's width direction. The actual windward area of ​​the vessel is determined based on the windward area of ​​its front and sides.

3. The method for determining ship wind resistance according to claim 2, characterized in that, The height above the waterline, the beam of the vessel, the frontal block coefficient, the angle between the wind direction and the beam direction of the vessel, and the windward area of ​​the vessel's front satisfy the following relationship: The windward area of ​​a ship's front = height above water × ship's beam × frontal block coefficient × cos (angle between wind direction and ship's beam direction). The height above the waterline, the length of the vessel, the block coefficient of the sides, the angle between the wind direction and the width direction of the vessel, and the windward area of ​​the vessel's sides satisfy the following relationship: The windward area of ​​a ship's side = height above water × ship's length × side block coefficient × sin (angle between wind direction and the ship's width direction).

4. The method for determining ship wind resistance according to claim 1, characterized in that, The first feature information includes one or more of the following features: ship length, ship width, and ship type.

5. The method for determining ship wind resistance according to claim 1, characterized in that, The second feature information includes one or more of the following features: The historical frequency of vessel calls, sailing duration, sailing speed, berthing time, waiting time, average of the target berth call rate, standard deviation of the target berth call rate, kurtosis of the target berth call rate, and skewness of the target berth call rate.

6. The method for determining ship wind resistance according to claim 1, characterized in that, In the step of determining the ship's wind resistance based on the actual wind-receiving area and the wind speed, the actual wind-receiving area, the wind speed, and the wind resistance satisfy the following relationship: Wind resistance = 0.5 × air density × actual wind-receiving area × drag coefficient × wind speed × wind speed.

7. A device for determining ship wind resistance, characterized in that, include: The information acquisition module is used to acquire the ship's AIS information; The determination module is used to determine the maximum draft of the vessel based on the AIS information; The determining module is further configured to determine the height of the upper deck of the vessel based on the vessel's maximum draft and the vessel's height. The determining module is further configured to determine the current draft of the vessel based on the AIS information; The determining module is further configured to determine the height of the vessel above the waterline based on the maximum draft, the upper deck height, and the current draft; The information acquisition module is also used to acquire the angle between the wind direction and the width direction of the ship; The determining module is further configured to input the ship's length, the ship's beam, and the ship's type into the first prediction model to predict the ship's block coefficient. The determining module is further configured to determine the actual windward area of ​​the vessel based on the height above the water surface, the length of the vessel, the width of the vessel, the angle between the wind direction and the width direction of the vessel, and the block coefficient of the vessel. The information acquisition module is also used to acquire wind speed; The determining module is also used to determine the wind resistance of the ship based on the ship's actual windward area and the wind speed; The AIS information includes MMSI information. The determining module is specifically used for: obtaining the ship's registration file information based on the MMSI information; determining whether the registration file information includes the ship's maximum draft; when the registration file information includes the ship's maximum draft, determining the ship's maximum draft; when the registration file information does not include the ship's maximum draft, extracting the ship's first feature information from the ship's AIS information, inputting the first feature information into a second prediction model, and simulating and predicting the ship's maximum draft through the second prediction model. The determining module is further specifically used for: determining whether the AIS information includes the current draft of the vessel; when the AIS information includes the current draft of the vessel, determining the current draft of the vessel; when the AIS information does not include the current draft of the vessel, obtaining the vessel's registration file information based on the MMSI information, extracting the vessel's second feature information from the registration file information, inputting the second feature information into a third prediction model, and simulating and predicting the current draft of the vessel through the third prediction model.

8. An electronic device, characterized in that, include: A memory and a processor, wherein the memory stores a computer program or instructions, and the processor executes the computer program or instructions to implement the ship wind resistance determination method as described in any one of claims 1 to 6.

9. A readable storage medium, characterized in that, The readable storage medium stores a program or instructions, and when the processor executes the program or instructions, it implements the ship wind resistance determination method as described in any one of claims 1 to 6.

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