Load tonnage and wind area calculation model, wind area acquisition method and device

Abstract

The application discloses a load tonnage and wind area calculation model, a wind area acquisition method and device, and relates to the technical field of ship data calculation. The method comprises the following steps: acquiring ballast draft values of ships with different load tonnages according to real-time draft values of the ships; acquiring full-load wind areas of the ships with different load tonnages under full-load draft states and ballast wind areas of the ships under ballast draft states under different preset guarantee rates; establishing a ship wind area database for indicating mapping relationships between different load tonnages and corresponding full-load wind areas and ballast wind areas under different preset guarantee rates; and fitting a quantitative mapping relationship between the load tonnage and the wind area by using different preset fitting modes according to data in the ship wind area database, so as to obtain a fitting model corresponding to each preset fitting mode, and selecting a fitting model with the largest determination coefficient as a final load tonnage-wind area calculation model.

Description

Technical Field

[0001] This application relates to the field of ship data calculation technology, and in particular to a calculation model for deadweight tonnage and windward area, a method and apparatus for obtaining windward area. Background Technology

[0002] In the field of port and waterway design, the calculation of moored vessel loads is a core technical aspect that ensures the structural safety and long-term operational stability of infrastructure such as wharves and waterways. The windward area of ​​a vessel is a key fundamental parameter for calculating moored vessel loads; its calculation accuracy, acquisition efficiency, and applicable vessel types directly determine the reliability and accuracy of the load calculation results, thus fundamentally affecting the rationality and safety of port and waterway engineering design schemes.

[0003] Currently, the calculation of a ship's windward area mainly relies on the existing "Port Engineering Load Code", which only provides windward area data for specific ship types.

[0004] In port and waterway engineering design practice, when key parameters such as the target vessel's deadweight tonnage and hull dimensions are not entirely consistent with the standard vessel type recorded in the "Port Engineering Load Code," designers must first find the two sets of reference data closest to the target vessel from the limited data in the "Port Engineering Load Code," and then derive the windward area of ​​the target vessel through manual calculation using linear interpolation or nonlinear fitting. This process requires designers to compare data one by one, set interpolation formulas, and manually verify the results. This method can lead to inaccurate calculations of the vessel's windward area due to human calculation errors. Summary of the Invention

[0005] The purpose of this application is to provide a calculation model for deadweight tonnage and windward area, a method and apparatus for obtaining windward area, which can improve the accuracy of ship windward area calculation.

[0006] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a method for obtaining a calculation model for load capacity and windward area, characterized in that the method includes: Based on the real-time draft of ships with different deadweight tons, obtain the ballast draft of ships with different deadweight tons. Under different preset guarantee rates, the windward area of ​​ships with different deadweight tons under full load draft and the windward area under ballast draft are obtained; where the draft line for measuring the windward area under full load corresponds to the full load draft value, and the draft line for measuring the windward area under ballast corresponds to the ballast draft value. A ship windward area database is established, which is used to indicate the mapping relationship between different deadweight tons and the corresponding full-load windward area and ballast windward area under different preset guarantee rates; Based on data from the ship windward area database, different preset fitting methods are used to fit the quantitative mapping relationship between deadweight tonnage and windward area to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

[0007] Secondly, this application provides a device for obtaining a calculation model of load capacity and windward area, the device comprising: The first acquisition module is used to acquire the ballast draft of ships with different deadweight tons based on the real-time draft of ships with different deadweight tons. The second acquisition module is used to acquire the full-load windward area of ​​ships with different deadweight tons under different preset guarantee rates, and the ballast windward area under different ballast drafts; wherein, the draft line for measuring the full-load windward area corresponds to the full-load draft value, and the draft line for measuring the ballast windward area corresponds to the ballast draft value. A module is established to create a database of ship windward areas. This database indicates the mapping relationship between different deadweight tons and their corresponding full-load and ballast windward areas under different preset guarantee rates. The analysis module is used to fit the quantitative mapping relationship between deadweight tonnage and windward area based on data in the ship windward area database using different preset fitting methods, so as to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

[0008] Thirdly, this application provides a method for obtaining wind-receiving area, the method comprising: Obtain the current deadweight tonnage of the vessel; The windward area of ​​the current ship is obtained by using the deadweight tonnage and windward area calculation model obtained in the first aspect, and the deadweight tonnage of the current ship.

[0009] According to the specific embodiments provided in this application, the following technical effects are disclosed: In this disclosure, the corresponding ballast draft is first determined based on the real-time draft of ships with different deadweight tonnages. Then, the windward area of ​​the ship under two draft states (full load and ballast) under different preset guarantee rates is obtained, and a database containing the mapping relationship between deadweight tonnage and corresponding windward area is constructed. Subsequently, based on the data in the ship windward area database, different preset fitting methods are used to fit the quantitative mapping relationship between deadweight tonnage and windward area to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model. When obtaining the windward area, it is only necessary to substitute the deadweight tonnage of the target ship into the final deadweight tonnage-windward area calculation model to automatically calculate the windward area of ​​the target ship. In this way, designers do not need to compare data one by one, set interpolation formulas, and manually verify the results, thereby avoiding the problem of inaccurate ship windward area calculation due to human calculation errors. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a flowchart illustrating a method for obtaining a calculation model for deadweight tonnage and windward area according to an exemplary embodiment; Figure 2 This is a fitted curve diagram using a power function fitting according to an exemplary embodiment; Figure 3 This is a fitting curve diagram using polynomial (third order) fitting, as shown according to an exemplary embodiment; Figure 4 This is a fitted curve diagram using logarithmic fitting, as shown according to an exemplary embodiment; Figure 5 This is a fitted curve diagram using Logistic fitting, as illustrated in an exemplary embodiment. Figure 6 This is a schematic diagram of the functional modules of a device for obtaining a calculation model of load capacity and windward area according to an exemplary embodiment. Detailed Implementation

[0012] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0013] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0014] Figure 1 This is a flowchart illustrating a method for obtaining a calculation model for load capacity and windward area according to an exemplary embodiment, such as... Figure 1 As shown, the method includes the following steps S101-S104: In step S101, the ballast draft of ships with different deadweight tons is obtained based on the real-time draft of ships with different deadweight tons.

[0015] In one embodiment, step S101 includes the following sub-steps S1011-S1014: S1011. Obtain actual ship data and real-time draft values ​​of each deadweight tonnage vessel at different time points; the actual ship data includes: deadweight tonnage and full-load draft values ​​of each vessel.

[0016] Deadweight tonnage refers to the total weight (unit: t) that a ship can carry when fully loaded, including cargo, fuel, fresh water, crew, and supplies. It is a core parameter characterizing the size of a ship and directly determines the range of its windward area.

[0017] Full load draft refers to the depth (in meters) of a ship's hull submerged in water when it is fully loaded with its deadweight tonnage. It is the benchmark parameter for calculating the non-full load draft coefficient β.

[0018] In step S1011, the real-time draft values ​​of each deadweight tonnage vessel at different time points are obtained, including the following steps A1-A2: A1. Obtain the real-time draft values ​​of ships of various deadweight tons at different time points; A2. Delete data in the original real-time draft that is greater than the full load draft, and delete data in the original real-time draft that is less than the full load draft by a preset percentage. The remaining original real-time draft is the original real-time draft value.

[0019] This step is used to clean up outlier data in the raw real-time draft values, removing raw real-time draft values ​​of ships that meet any of the following conditions: Real-time draft value > full load draft value (exceeds the ship's full load limit, data is invalid); Real-time draft raw value < preset percentage of full-load draft value (significantly deviates from the normal draft range and is judged as abnormal data); For example, the preset percentage can be 10%, in which case the second condition can be: The original draft value is less than 10% of the full load draft value.

[0020] For example, actual ship data can be obtained through Lloyd's database.

[0021] Specifically, the Lloyd's database can be linked through the ship's unique identifier (MMSI number or IMO number) to obtain actual ship data (including but not limited to: ship name, actual ship photo or ship type diagram, deadweight tonnage, displacement, beam, depth, and full load draft).

[0022] For example, the raw draft values ​​of ships of various deadweight tons at different points in time can be obtained through the AIS database.

[0023] Specifically, the real-time draft can be obtained by linking the vessel's unique identifier (MMSI number or IMO number) to the AIS database. As a mandatory navigation device installed on ships, the AIS system can transmit real-time dynamic data of the vessel on a minute-by-minute basis. The real-time draft recorded by the system is actual measured data of the actual vessel, which can truly reflect the changes in the actual loading conditions of the vessel and is more representative than traditional experience-based estimation data.

[0024] At this point, steps A1-A2 above are used to clean up abnormal data in the raw real-time draft values ​​of the AIS database.

[0025] By implementing the above steps to remove abnormal data, only valid real-time draft values ​​are retained for calculating the non-full-load draft coefficient, thus avoiding the impact of abnormal data on the accuracy of the coefficient.

[0026] S1012. Obtain the non-full load draft coefficient of each deadweight tonnage vessel at different time points based on the full load draft value and the real-time draft value at different time points.

[0027] In one embodiment, the ratio of the real-time draft to the full-load draft of each deadweight tonnage vessel at different time points is calculated, whereby the ratio is the non-full-load draft coefficient of each deadweight tonnage vessel at different time points. .

[0028] For example, β = real-time draft / full load draft; The non-full load draft coefficient β is essentially the ratio of the ship's "draft under actual loading conditions" to "draft under full load conditions". This ratio can intuitively reflect the degree to which the ship's current loading conditions deviate from the full load state.

[0029] When β≈1, the ship is close to or fully loaded. When β < 1, the ship is not fully loaded (the smaller the β value, the smaller the ship's deadweight and the closer it is to ballast).

[0030] For a single vessel, based on its real-time draft values ​​at multiple time points, the β value corresponding to each time point is calculated to form a β value sequence for the vessel (e.g., the β values ​​of a 300,000-ton vessel on January 7, April 16, and July 21, 2024 are 0.461, 0.461, and 0.457, respectively). For multiple vessels of the same tonnage, the β value sequence for each vessel is calculated separately, and the results are accumulated to form a β value sample set for vessels of that tonnage.

[0031] S1013. Based on the non-full load draft coefficient of ships of various deadweight tons at different time points. Obtain the minimum reasonable ballast draft coefficient for ships of various deadweight tons.

[0032] In one embodiment, step S1031 includes performing the following steps B1-B3 on the non-full load draft coefficient of each deadweight tonnage vessel at different time points: B1. Non-full load draft coefficient for all time points of a ship with a current deadweight tonnage. Statistical analysis was conducted to establish the distribution intervals of the non-full load draft coefficient, as well as the proportion of the non-full load draft coefficient corresponding to each distribution interval.

[0033] The β values ​​of all ships of the same deadweight tonnage (e.g., 5000t, 300000t) are aggregated to form a total β value sample pool for that tonnage class (e.g., the total sample pool of 300,000-ton bulk carriers contains all the β values ​​of 126 ships).

[0034] Divide the data into continuous and non-overlapping distribution intervals based on the size of the β value. The interval division should take into account both the data distribution density and statistical accuracy. It is recommended that the interval span be 0.1 (such as 0.31≤β<0.4, 0.4≤β<0.5, 0.5≤β<0.6, etc.) to ensure that the β value range of all samples is covered.

[0035] The number of samples in each distribution interval is counted, and the proportion of each interval is calculated using the formula "interval proportion = (number of samples in the interval / total number of samples) × 100%" to determine the frequency of occurrence of each β value interval in the tonnage of the ship.

[0036] B2. Obtain the percentage that is less than the preset percentage.

[0037] The percentage of each distribution interval is compared with the preset percentage, and all percentages with a cumulative percentage less than the preset percentage are filtered out.

[0038] B3. The value corresponding to the largest distribution interval among the percentages less than the preset percentage is the minimum reasonable ballast draft coefficient of the ship with the current deadweight tonnage.

[0039] For example, if the percentages less than the preset percentages are 9.5%, 8.7%, and 4.0%, then the value corresponding to the distribution interval of 9.5% is selected as the minimum reasonable ballast draft coefficient β for the current deadweight tonnage of the vessel. It is worth noting that if the distribution interval corresponding to 9.5% is a single-value interval (e.g., β < 0.3), then the minimum reasonable ballast draft coefficient for the current deadweight tonnage of the vessel is 0.3. If the distribution interval corresponding to 9.5% is a single-value interval (e.g., 0.4 ≤ β < 0.5), then the minimum reasonable ballast draft coefficient for the current deadweight tonnage of the vessel is the lower limit of the interval, which is 0.4.

[0040] S1014. Obtain the ballast draft of each deadweight tonnage vessel based on the minimum reasonable ballast draft coefficient and the full load draft.

[0041] Ballast draft = minimum reasonable ballast draft coefficient × full load draft.

[0042] In step S102, the windward area of ​​ships with different deadweight tons under full load draft and the windward area of ​​ballast draft are obtained under different preset guarantee rates; wherein, the draft line for measuring the windward area under full load corresponds to the full load draft value, and the draft line for measuring the windward area under ballast corresponds to the ballast draft value.

[0043] In one embodiment, the actual ship data includes: actual ship photographs or ship type diagrams.

[0044] Geometric area measurements can be performed on actual ship photos or ship type diagrams. The waterline for measuring the windward area at full load corresponds to the full load draft, and the waterline for measuring the windward area at ballast corresponds to the ballast draft.

[0045] Specifically, for paper documents, the windward area is obtained by measuring with a ruler and converting it proportionally; for electronic documents, the windward area is obtained by using geometric measuring tools and converting it proportionally.

[0046] The wind-receiving area in this disclosure includes: the lateral wind-receiving area and the longitudinal wind-receiving area.

[0047] The transverse windward area refers to the projected area of ​​the hull above the waterline, perpendicular to the transverse wind direction, when a ship is exposed to wind laterally (perpendicular to the horizontal direction connecting the bow and stern). Essentially, it is the effective windward profile area of ​​the ship's side (hull direction), directly determining the magnitude of the transverse wind force on the ship. It is a core parameter for calculating the transverse load of moored vessels in port and waterway design.

[0048] The longitudinal windward area refers to the projected area of ​​the hull above the waterline, perpendicular to the longitudinal wind direction, when a ship is exposed to wind in the longitudinal direction (parallel to the horizontal direction connecting the bow and stern). Essentially, it is the effective windward profile area of ​​the ship in the bow-stern direction, influencing the thrust or pull of the longitudinal wind on the ship, and is a key basis for calculating the longitudinal load of moored vessels.

[0049] After obtaining the windward area, the guarantee rate analysis of the windward area can be performed using SPSS data analysis software to obtain the full-load windward area of ​​ships with different deadweight tons under full-load draft and the ballast windward area under ballast draft under different preset guarantee rates.

[0050] For example, the preset guarantee rates can include: 50%, 75%, 90%, and 95%.

[0051] In step S103, a ship windward area database is established. The ship windward area database is used to indicate the mapping relationship between different deadweight tons and the corresponding full-load windward area and ballast windward area under different preset guarantee rates.

[0052] The database of ship windward area is shown in Table 1: Table 1. Database of Ship Windward Area

[0053] Table 1 only shows the tables for 50% and 75% guarantee rates. In actual scenarios, Table 1 will show the lateral and longitudinal wind-receiving areas corresponding to all guarantee rates. Simply fill in the corresponding data in the corresponding positions in Table 1.

[0054] In step S104, based on the data in the ship windward area database, different preset fitting methods are used to fit the quantitative mapping relationship between deadweight tonnage and windward area to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

[0055] In one embodiment, the preset fitting method includes: power function fitting, polynomial fitting, logarithmic fitting, and logistic fitting.

[0056] The following four fitting formulas are used for fitting: Power function fitting was used: Where x represents deadweight tons; y represents the windward area of ​​the ship; a represents a constant term, a fixed offset obtained from the fitting calculation, which characterizes the theoretical windward area benchmark value when the deadweight tons approach 0; b represents a proportionality coefficient, which adjusts the overall amplitude of the power function and controls the rate of change of the windward area with the deadweight tons; c represents a power exponent, which determines the degree of nonlinearity of the change of the windward area with the deadweight tons. When c > 0, the windward area increases with the increase of the deadweight tons.

[0057] Polynomial fitting was used: Where x represents deadweight tons; y represents the windward area of ​​the ship; Int represents the constant term, which has the same meaning as 'a' in the power function, and is the theoretical baseline value of the windward area when deadweight tons x=0; B1 represents the linear coefficient, which characterizes the basic rate of linear growth of windward area with deadweight tons; B2 represents the quadratic coefficient, which adjusts the curvature of nonlinear growth and reflects the acceleration or deceleration trend of windward area with deadweight tons growth; B3 represents the cubic coefficient, which further corrects the details of the nonlinear relationship and optimizes the model's fitting accuracy for data of large deadweight ships (such as those over 300,000 tons).

[0058] Log-fitting was used: Where x represents deadweight tons; y represents the ship's windward surface area; This represents the principal constant term, which determines the overall height benchmark of the fitted curve and is the core offset parameter of the model. This represents the logarithmic coefficient, which adjusts the steepness of the logarithmic curve and controls the rate at which the windward area increases with load capacity in tons. This represents the offset constant term, used to adjust the starting point of the independent variable x, to avoid meaningless values ​​in ln(x) when x approaches 0, and to optimize the model's fit to data from small deadweight ships.

[0059] Logistic fitting was used: Where x represents deadweight tonnage; y represents the windward area of ​​the ship; A1 represents the lower limit asymptotic value, which represents the theoretical minimum limit of the windward area when the deadweight tonnage approaches 0; A2 represents the upper limit asymptotic value, which represents the theoretical maximum limit of the windward area when the deadweight tonnage approaches infinity, reflecting the physical upper limit of the ship's windward area (limited by the ship's structure and dimensions). This represents the midpoint parameter, corresponding to the "inflection point" of the curve with the fastest growth rate in deadweight tons, i.e., when x = At that time, the wind-receiving area reaches (A1+A2) / 2; p represents the shape parameter, which adjusts the steepness of the S-curve. The larger the p value, the sharper the inflection point of the curve (the more concentrated the growth stage), and the smaller the p value, the smoother the curve.

[0060] For the four formulas, R squared (R 2By comparing the coefficient of determination (R²), the fitting formula corresponding to the maximum value of R² is selected to establish a load-tonnage-wind-area function fitting model.

[0061] In this disclosure, the corresponding ballast draft is first determined based on the real-time draft of ships with different deadweight tonnages. Then, the windward area of ​​the ship under two draft states (full load and ballast) under different preset guarantee rates is obtained, and a database containing the mapping relationship between deadweight tonnage and corresponding windward area is constructed. Subsequently, based on the data in the ship windward area database, different preset fitting methods are used to fit the quantitative mapping relationship between deadweight tonnage and windward area to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model. When obtaining the windward area, it is only necessary to substitute the deadweight tonnage of the target ship into the final deadweight tonnage-windward area calculation model to automatically calculate the windward area of ​​the target ship. In this way, designers do not need to compare data one by one, set interpolation formulas, and manually verify the results, thereby avoiding the problem of inaccurate ship windward area calculation due to human calculation errors.

[0062] Taking the calculation of the ballast draft of a 300,000-ton bulk carrier as an example: 1) Ship type matching.

[0063] (1) Link to Lloyd's database to obtain actual ship data for 300,000-ton bulk carriers. As of May 2024, there were 126 300,000-ton bulk carriers in operation, with a deadweight range of 275,001 to 312,500 tons. Select the ship SEABxx in the database, with IMO number 111111 and a full-load draft of 23.0m; (2) Link to the AIS database and obtain the real-time draft data of the IMO number 111111 on January 7, 2024, which is 10.6m.

[0064] 2) AIS retrieves and calculates the ship's real-time draft. .

[0065] (1) Data preprocessing: Taking a real-time draft of 10.6m as an example: (Real-time draft = 10.6m) < (Full-load draft = 23.0m); (Real-time draft = 10.6m) > (10% full load draft = 2.3m); Therefore, the original draft value of 10.6m can be judged as normal and is the real-time draft value.

[0066] The above judgment process is performed sequentially for each real-time draft value to filter out all real-time draft values.

[0067] (2) The real-time draft value is 10.6m; (3) Calculation ; = (Real-time draft = 10.6m) / (Full-load draft = 23.0m) = 0.461; (4) Repeat the above steps multiple times for the vessel with IMO number 111111 to obtain the real-time draft value of 10.6m on April 16, 2024, and calculate. The real-time draft value on July 21, 2024 was obtained as 10.5m. Calculations were performed. The real-time draft value on August 11, 2024 was obtained as 14.0m. Calculations were performed. .

[0068] 3) Establish The sample distribution was analyzed to determine the minimum reasonable ballast draft coefficient.

[0069] To obtain the minimum reasonable ballast draft coefficient, AIS data for each actual ship was collected, and the coefficient for each ship was calculated. ( The non-full load draft coefficient (i.e., the ratio of the ship's actual draft to its full load draft) was calculated. The ship's real-time draft was repeatedly checked and statistically analyzed to update the minimum ballast draft. Finally, the minimum ballast draft corresponding to each actual ship was calculated. Statistical analysis was conducted to determine the minimum reasonable ballast draft coefficient for ships of different tonnages. The statistical results are shown in Table 2. Table 2. Actual measurements of bulk carriers Sample distribution

[0070] For 300,000-ton bulk carriers The sample percentage is 9.5%, closest to 10%. Therefore, when calculating the windward area of ​​a 300,000-ton bulk carrier under ballast conditions, the minimum reasonable ballast draft coefficient is... =0.31.

[0071] Based on the minimum reasonable ballast draft coefficient of 0.31, the ballast draft of the actual ship is determined.

[0072] The ballast draft of ships with different deadweight tons can be obtained using the above method.

[0073] 4) Calculation of wind-receiving area.

[0074] Measure the windward area under full load based on the ship's form drawing. The waterline corresponds to the full load draft during this measurement. Measure the windward area under ballast based on the ship's form drawing. The waterline corresponds to the ballast draft during this measurement. Analyze the windward area values ​​of the ship under full load and ballast conditions at four guarantee rates: 50%, 75%, 90%, and 95%.

[0075] 5) Establish a database of the windward area of ​​ships.

[0076] Statistical analysis and deadweight tonnage classification are performed using real ship data from the Lloyd's database. Ship data is stored by tonnage level, and a database of ship windward area is established.

[0077] Measure the full-load windward area according to the hull form. When measuring the full-load windward area, the waterline corresponds to the full-load draft. For some vessels for which the hull form is not available, first compare the hull dimensions. If they are sister ships, use their full-load windward area; if they are not sister ships, measure the area based on the actual ship photos and hull dimensions provided in relevant documents, combined with the hull form of a vessel of the same tonnage.

[0078] The obtained database of ship windward areas is shown in Tables 3 and 4: Table 3. Ship Windward Area Database

[0079] Table 4. Ship Windward Area Database II

[0080] 6) Fitting analysis of load capacity to wind-receiving area.

[0081] Wind-receiving area A with a 75% guarantee rate xw For example: By accessing the deadweight tonnage and corresponding windward area values ​​from the "Ship Windward Area Database," the following four fitting formulas are used for fitting analysis: Power function fitting was used: The fitted curve is as follows Figure 2 As shown in Table 5: Table 5. Power function fitting results

[0082] Polynomial (third order) fitting was used: The fitted curve is as follows Figure 3 As shown in Table 6: Table 6. Polynomial (Third Order) Fitting Results

[0083] Log-fitting was used: The fitted curve is as follows Figure 4 As shown in Table 7, the fitting results are as follows: Table 7 Log-fit results

[0084] Logistic fitting was used: The fitted curve is as follows Figure 5 As shown in Table 8: Table 8 Logistic Fitting Results

[0085] When the sample size is expanded to all deadweight tons, the R-squared values ​​of all types of curves can reach 0.99, indicating a good fit. The power function fitting formula corresponding to the maximum R-squared value is selected to establish a deadweight ton-wind-area function fitting model.

[0086] Similarly, the wind-receiving area A with a 75% guarantee rate can be obtained. yw The load-wind area function fitting model, and the load-wind area function fitting model for windward area under other guarantee rates.

[0087] This disclosure has the following groundbreaking breakthroughs compared to the prior art: 1) A novel method for calculating the windward area of ​​ships based on real-time AIS data is proposed for the first time; 2) A method for calculating the windward area of ​​ultra-large ships is proposed for the first time; 3) A hierarchical statistical calculation model for ballast draft coefficient with dynamic threshold adjustment is proposed for the first time; 4) The standard for determining the minimum reasonable ballast draft coefficient is proposed for the first time; 5) For the first time, a calculation model for the minimum reasonable ballast draft coefficient and ballast wind-receiving area was established; 6) For the first time, a standard for determining the minimum reasonable ballast draft coefficient for a certain type of cargo is proposed, categorized by tonnage and cargo type; 7) For the first time, a calculation model for the minimum reasonable ballast draft coefficient and ballast wind-receiving area was established by tonnage and cargo type; 8) For the first time, a fitting analysis was conducted on the windward area of ​​ships under different deadweight tonnage and different guarantee rates, and a fitting formula was compiled.

[0088] This disclosure has the following significant advantages over the prior art: 1. Improved work efficiency.

[0089] By combining AIS real-time data with Lloyd's static database, the user's work efficiency will be greatly improved compared to obtaining data through table lookup and interpolation in the "Port Engineering Load Code".

[0090] 2. Improved accuracy.

[0091] By using a dynamic draft correction algorithm, the calculation error of the windward area is reduced compared to the interpolation process in the "Port Engineering Load Code".

[0092] 3. Real-time breakthrough.

[0093] Based on AIS data streams, updates are achieved at the minute level, enabling real-time updates compared to the static data in the "Port Engineering Load Code".

[0094] 4. Expanded coverage.

[0095] For the first time, it supports vessels of all tonnage scales, including very large bulk carriers of 300,000 tons and above.

[0096] Based on the same inventive concept, this application also provides a device for obtaining the load capacity and windward area calculation model to implement the above-mentioned method for obtaining the load capacity and windward area calculation model. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the device for obtaining the load capacity and windward area calculation model provided below can be found in the limitations of the method for obtaining the load capacity and windward area calculation model above, and will not be repeated here.

[0097] In one exemplary embodiment, such as Figure 6 As shown, a device for obtaining a calculation model of load capacity and windward area is provided, comprising: The first acquisition module is used to acquire the ballast draft of ships with different deadweight tons based on the real-time draft of ships with different deadweight tons. The second acquisition module is used to acquire the full-load windward area of ​​ships with different deadweight tons under different preset guarantee rates, and the ballast windward area under different ballast drafts; wherein, the draft line for measuring the full-load windward area corresponds to the full-load draft value, and the draft line for measuring the ballast windward area corresponds to the ballast draft value. A module is established to create a database of ship windward areas. This database indicates the mapping relationship between different deadweight tons and their corresponding full-load and ballast windward areas under different preset guarantee rates. The analysis module is used to fit the quantitative mapping relationship between deadweight tonnage and windward area based on data in the ship windward area database using different preset fitting methods, so as to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

[0098] In one embodiment, in the aspect of obtaining the ballast draft of ships with different deadweight tons based on their real-time draft values, the first obtaining module is specifically used for: Acquire actual ship data and real-time draft values ​​of ships of various deadweight tons at different points in time; the actual ship data includes: deadweight tons and full-load draft values ​​of each ship. The non-full load draft coefficient of each deadweight tonnage vessel at different time points is obtained based on the full load draft value and the real-time draft value at different time points. The minimum reasonable ballast draft coefficient for each deadweight tonnage vessel is obtained based on the non-full load draft coefficient at different time points. The ballast draft of each deadweight tonnage vessel is obtained based on the minimum reasonable ballast draft coefficient and the full load draft.

[0099] In one embodiment, regarding the acquisition of the real-time draft values ​​of ships of various deadweight tons at different points in time, the first acquisition module is specifically used for: Obtain the real-time raw draft values ​​of ships of various deadweight tons at different points in time; Delete data in the original real-time draft that is greater than the full load draft, and delete a preset percentage of data in the original real-time draft that is less than the full load draft. The remaining original real-time draft is the original real-time draft value.

[0100] In one embodiment, in obtaining the non-full-load draft coefficient of each deadweight tonnage vessel at different time points based on the full-load draft value of each deadweight tonnage vessel and the real-time draft value at different time points, the first acquisition module is specifically used for: Calculate the ratio of the real-time draft to the full-load draft of each deadweight tonnage vessel at different time points. The ratio is the non-full-load draft coefficient of each deadweight tonnage vessel at different time points.

[0101] In one embodiment, In the aspect of obtaining the minimum reasonable ballast draft coefficient of each deadweight tonnage vessel based on the non-full load draft coefficient at different time points, the first acquisition module is specifically used for: The following steps were performed on the non-full load draft coefficient of ships of various deadweight tons at different time points: Statistical analysis was conducted on the non-full load draft coefficient of ships with current deadweight tonnage at all time points to establish various distribution intervals of the non-full load draft coefficient and the proportion of the non-full load draft coefficient corresponding to each distribution interval. Get the percentage that is less than a preset percentage; The value corresponding to the largest distribution interval among the percentages less than the preset percentage is the minimum reasonable ballast draft coefficient for the current deadweight tonnage of the vessel.

[0102] In one embodiment, the preset fitting method includes: Power function fitting, polynomial fitting, logarithmic fitting, and logistic fitting.

[0103] In one embodiment, regarding the acquisition of actual ship data, the first acquisition module is specifically used for: Obtain actual ship data from Lloyd's database.

[0104] In one embodiment, regarding the acquisition of the real-time draft of each deadweight tonnage vessel at different time points, the first acquisition module is specifically used for: The raw draft values ​​of ships of various deadweight tons at different points in time are obtained through the AIS database.

[0105] This disclosure also provides a method for obtaining wind-receiving area, the method comprising: Obtain the current deadweight tonnage of the vessel; The windward area of ​​the current ship is obtained by using the deadweight tonnage and windward area calculation model obtained by any of the above embodiments and the deadweight tonnage of the current ship.

[0106] This disclosure also provides a windward area acquisition device, the device comprising: The third acquisition module is used to acquire the current deadweight tonnage of the ship; The fourth acquisition module is used to acquire the windward area of ​​the current ship using the deadweight tonnage and windward area calculation model obtained as in any of the above embodiments, and the deadweight tonnage of the current ship.

[0107] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for obtaining a calculation model for load capacity and windward area, characterized in that, The method includes: Based on the real-time draft of ships with different deadweight tons, obtain the ballast draft of ships with different deadweight tons. Under different preset guarantee rates, the windward area of ​​ships with different deadweight tons under full load draft and the windward area under ballast draft are obtained; where the draft line for measuring the windward area under full load corresponds to the full load draft value, and the draft line for measuring the windward area under ballast corresponds to the ballast draft value. A ship windward area database is established, which is used to indicate the mapping relationship between different deadweight tons and the corresponding full-load windward area and ballast windward area under different preset guarantee rates; Based on data from the ship windward area database, different preset fitting methods are used to fit the quantitative mapping relationship between deadweight tonnage and windward area to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

2. The method according to claim 1, characterized in that, The process of obtaining the ballast draft of ships with different deadweight tons based on their real-time draft includes: Acquire actual ship data and real-time draft values ​​of ships of various deadweight tons at different points in time; the actual ship data includes: deadweight tons and full-load draft values ​​of each ship. The non-full load draft coefficient of each deadweight tonnage vessel at different time points is obtained based on the full load draft value and the real-time draft value at different time points. The minimum reasonable ballast draft coefficient for each deadweight tonnage vessel is obtained based on the non-full load draft coefficient at different time points. The ballast draft of each deadweight tonnage vessel is obtained based on the minimum reasonable ballast draft coefficient and the full load draft.

3. The method according to claim 2, characterized in that, The acquisition of the real-time draft values ​​of ships of various deadweight tons at different time points includes: Obtain the real-time raw draft values ​​of ships of various deadweight tons at different points in time; Delete data in the original real-time draft that is greater than the full load draft, and delete a preset percentage of data in the original real-time draft that is less than the full load draft. The remaining original real-time draft is the original real-time draft value.

4. The method according to claim 3, characterized in that, The process of obtaining the non-full load draft coefficient of each deadweight tonnage vessel at different time points based on the full load draft and real-time draft at different time points includes: Calculate the ratio of the real-time draft to the full-load draft of each deadweight tonnage vessel at different time points. The ratio is the non-full-load draft coefficient of each deadweight tonnage vessel at different time points.

5. The method according to claim 4, characterized in that, The process of obtaining the minimum reasonable ballast draft coefficient for each deadweight tonnage vessel based on its non-full load draft coefficient at different time points includes: The following steps were performed on the non-full load draft coefficient of ships of various deadweight tons at different time points: Statistical analysis was conducted on the non-full load draft coefficient of ships with current deadweight tonnage at all time points to establish various distribution intervals of the non-full load draft coefficient and the proportion of the non-full load draft coefficient corresponding to each distribution interval. Get the percentage that is less than a preset percentage; The value corresponding to the largest distribution interval among the percentages less than the preset percentage is the minimum reasonable ballast draft coefficient for the current deadweight tonnage of the vessel.

6. The method according to claim 1, characterized in that, The preset fitting method includes: Power function fitting, polynomial fitting, logarithmic fitting, and logistic fitting.

7. The method according to claim 2, characterized in that, The acquisition of actual ship data includes: Obtain actual ship data from Lloyd's database.

8. The method according to claim 3, characterized in that, The process of obtaining the real-time draft values ​​of ships of various deadweight tons at different points in time includes: The raw draft values ​​of ships of various deadweight tons at different points in time are obtained through the AIS database.

9. A device for obtaining a calculation model of load capacity and windward area, characterized in that, The device includes: The first acquisition module is used to acquire the ballast draft of ships with different deadweight tons based on the real-time draft of ships with different deadweight tons. The second acquisition module is used to acquire the full-load windward area of ​​ships with different deadweight tons under different preset guarantee rates, and the ballast windward area under different ballast drafts; wherein, the draft line for measuring the full-load windward area corresponds to the full-load draft value, and the draft line for measuring the ballast windward area corresponds to the ballast draft value. A module is established to create a database of ship windward areas. This database indicates the mapping relationship between different deadweight tons and their corresponding full-load and ballast windward areas under different preset guarantee rates. The analysis module is used to fit the quantitative mapping relationship between deadweight tonnage and windward area based on data in the ship windward area database using different preset fitting methods, so as to obtain the fitting model corresponding to each preset fitting method. The fitting model with the largest determination coefficient among the preset fitting methods is selected as the final deadweight tonnage-windward area calculation model.

10. A method for obtaining wind-receiving area, characterized in that, The method includes: Obtain the current deadweight tonnage of the vessel; The deadweight tonnage and windward area calculation model obtained by the method of obtaining the deadweight tonnage and windward area calculation model as described in any one of claims 1-8, and the deadweight tonnage of the current ship, are used to obtain the windward area of ​​the current ship.

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