Ship performance evaluation method, device and equipment

Abstract

The present invention provides a method, device, and apparatus for evaluating ship performance. The method comprises: obtaining target environmental data and target ship performance data during ship operation; determining an actual delivered fuel consumption rate based on the target ship performance data; determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data; determining a reference delivered fuel consumption rate based on received ship model data and sea trial data; determining a ship comprehensive energy efficiency index based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate; and evaluating ship performance based on the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result. The present invention eliminates the influence of environmental, operational, and other factors in actual testing, can reflect the actual performance of a ship, and is of great significance to ship energy conservation and emission reduction.

Description

Technical Field

[0001] The present invention relates to the technical field of ships, and also to a method, device and equipment for evaluating ship performance. Background Art

[0002] Regular maintenance of ships is crucial to reducing performance degradation caused by marine biofouling, which not only helps reduce greenhouse gas emissions from the global fleet but also cuts operating costs. However, due to the high cost of ship maintenance, shipowners are often cautious about frequent maintenance. Therefore, an effective performance indicator is needed to monitor changes in the hydrodynamic performance of ships and optimize maintenance plans.

[0003] Existing technologies have proposed multiple indicators for evaluating changes in ship performance, such as the Energy Efficiency Operational Index (EEOI) and the Annualized Efficiency Ratio (AER). However, these indicators are easily affected by multiple factors, including weather, logistics, operating mode, ship speed, loading conditions, and ship maintenance status (such as hull and propeller fouling, damage, anti-fouling paint, etc.). As a result, the rating results cannot truly reflect the ship's energy-saving level and actual performance. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method, device and equipment for evaluating ship performance, so as to improve the accuracy of ship performance evaluation.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] A first aspect of the present invention provides a method for evaluating ship performance, comprising:

[0007] Acquire target environment data and target ship performance data during ship operation;

[0008] Determine the actual delivered fuel consumption rate based on the target ship performance data;

[0009] determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data;

[0010] Determine the reference delivery fuel consumption rate based on the received ship model data and sea trial data;

[0011] determining a comprehensive energy efficiency index of the ship based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate;

[0012] The ship performance is evaluated according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result.

[0013] Optionally, target environment data and target ship performance data are obtained during ship operation, including:

[0014] Get the preset sliding window;

[0015] Determining a standard deviation of environmental data based on the preset sliding window and the initial environmental data;

[0016] determining a standard deviation of the ship performance data based on the preset sliding window and the initial ship performance data;

[0017] Obtaining stable environmental data according to the environmental data standard deviation and a preset environmental standard deviation limit;

[0018] Obtaining stable ship performance data according to the ship performance data standard deviation and a preset ship performance standard deviation limit;

[0019] Target environment data and target ship performance data are obtained according to the stable environment data, the stable ship performance data and preset filtering criteria.

[0020] Optionally, determining the actual delivered fuel consumption rate based on the target ship performance data includes:

[0021] Based on the target ship performance data and 、 Determine actual delivered fuel consumption;

[0022] in, is the actual delivered fuel consumption rate, is the shaft power in the target ship performance data, Q is the torque in the target ship performance data, PRM is the shaft revolutions in the target ship performance data, FC is the fuel consumption, is the transmission efficiency of the shaft in the target ship performance data, and T is the measurement time.

[0023] Optionally, determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data includes:

[0024] According to the target environment data and , determine the resistance caused by the environment;

[0025] According to the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate;

[0026] in, ;

[0027] in, It is the resistance caused by the environment. is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, is the water speed in the target ship performance data, is the total ship efficiency in the target ship performance data, It is the fuel consumption caused by the change of resistance. is the correction power of the environment.

[0028] Optionally, based on the received ship model data and sea trial data, determine the reference delivery fuel consumption rate, including:

[0029] Receive ship model data and sea trial data;

[0030] Correcting the ship model data according to the difference between the ship model data and the sea trial data to obtain corrected ship model data;

[0031] A reference delivery fuel consumption rate is determined based on the corrected ship model data and the sea trial data.

[0032] Optionally, determining a comprehensive energy efficiency index of a ship according to the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate includes:

[0033] According to the reference delivery fuel consumption rate, the actual delivery fuel consumption rate, the environmental correction fuel consumption rate and , determine the comprehensive energy efficiency index of ships;

[0034] Among them, SCEI is the ship comprehensive energy efficiency index, is the actual delivered fuel consumption rate, is the environmentally corrected fuel consumption, is the reference delivered fuel consumption rate.

[0035] Optionally, the ship performance is evaluated according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result, including:

[0036] Obtaining a ship performance level according to the ship comprehensive energy efficiency index and a preset index threshold;

[0037] Obtaining a ship maintenance plan based on the ship performance level and pre-stored ship maintenance data;

[0038] The ship performance is evaluated according to the ship comprehensive energy efficiency index, the preset index threshold, the ship performance level, and the ship maintenance plan to obtain a ship performance evaluation result.

[0039] A second aspect of the present invention provides a device for evaluating ship performance, comprising:

[0040] An acquisition module is used to acquire target environment data and target ship performance data during ship operation;

[0041] A processing module is configured to determine an actual delivered fuel consumption rate based on the target ship performance data; determine an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data; determine a reference delivered fuel consumption rate based on the received ship model data and sea trial data; determine a comprehensive ship energy efficiency index based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate; and evaluate ship performance based on the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result.

[0042] According to a third aspect of the present invention, a computing device is provided, comprising: a processor and a memory storing a computer program, wherein when the computer program is executed by the processor, the method according to the first aspect is executed.

[0043] A fourth aspect of the present invention provides a computer-readable storage medium storing instructions, which, when executed on a computer, causes the computer to execute the method described in the first aspect.

[0044] The above solution of the present invention includes at least the following beneficial effects:

[0045] The above-mentioned scheme of the present invention obtains the target environmental data and target ship performance data during the operation of the ship, determines the actual delivered fuel consumption rate, the reference delivered fuel consumption rate and the environmental corrected fuel consumption rate, and calculates the ship's comprehensive energy efficiency index. Finally, the ship performance is evaluated according to the ship's comprehensive energy efficiency index and the preset index threshold to obtain the ship performance evaluation result, which eliminates the influence of environmental, operational and other factors in the actual test, can reflect the actual performance of the ship, and is of great significance to ship energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a schematic flow chart of a method for evaluating ship performance in an embodiment of the present invention;

[0047] Figure 2 4 is a schematic structural diagram of a device for evaluating ship performance in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0049] like Figure 1 As shown, an embodiment of the present invention provides a method for evaluating ship performance, comprising the following steps:

[0050] Step 101, obtaining target environment data and target ship performance data during ship operation;

[0051] Step 102: determining the actual delivered fuel consumption rate based on the target ship performance data;

[0052] Step 103, determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data;

[0053] Step 104: determining a reference delivery fuel consumption rate based on the received ship model data and sea trial data;

[0054] Step 105: determining a comprehensive energy efficiency index of the ship based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate;

[0055] Step 106: Evaluate the ship performance according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result.

[0056] The ship performance evaluation method proposed in the embodiment of the present invention obtains target environmental data and target ship performance data during ship operation, determines the actual delivered fuel consumption rate, the reference delivered fuel consumption rate, and the environmentally corrected fuel consumption rate, and calculates the ship's comprehensive energy efficiency index. Finally, the ship's performance is evaluated based on the ship's comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result. This eliminates the influence of environmental, operational, and other factors in actual testing, can reflect the actual performance of the ship, and is of great significance to ship energy conservation and emission reduction.

[0057] In an optional embodiment of the present invention, step 101 includes:

[0058] Step 1011: using a collection device installed on board the ship to obtain initial environmental data and initial ship performance data during ship operation.

[0059] Specifically, data can be collected according to the items and collection frequencies in the collection data table shown in Table 1. In specific implementation, in addition to the data in Table 1, other data can also be collected according to actual conditions. The data in Table 1 is only for illustrative purposes.

[0060] Table 1 Collection data table

[0061] project Acquisition frequency unit route Enter each route - Collection time Real-time collection UTC latitude Real-time collection Degree (°) longitude Real-time collection Degree (°) Shaft power Real-time collection Kilowatt (kW) Shaft speed Real-time collection Revolutions per minute (r / min) course Real-time collection Degree (°) Ship position coordinates Real-time collection Degrees (°), minutes (′), seconds (″) Calculate Date Real-time collection Year / Month / Day water temperature Real-time collection Celsius (℃) wind speed Real-time collection Meter per second (m / s) wind direction Real-time collection Degree (°) wave height Real-time collection meter (m) Wave direction Real-time collection Degree (°) Wave Cycle Real-time collection Seconds (s) Ground speed Real-time collection Knot (kn) Water speed Real-time collection Knot (kn) water depth Real-time collection meter (m) Displacement Real-time collection Ton (t) First draft Real-time collection meter (m) tail draft Real-time collection meter (m) fuel consumption Real-time collection kilograms per hour (kg / h) Fuel consumption rate Real-time collection Grams per kilowatt-hour (g / kWh)

[0062] Step 1012: Obtain a preset sliding window;

[0063] Specifically, different time periods can be set based on different data to determine the size of the preset sliding window. For example, in a specific embodiment, if the time period is 15 minutes, each window will contain data points within 15 minutes. As shown in Table 2, the size of the corresponding preset sliding window can be set based on the time period corresponding to the parameter type or name (such as shaft speed or ship heading, etc.) (represented as time period in Table 2):

[0064] Table 2 Sliding windows corresponding to various parameters

[0065] parameter Preset standard deviation limits Accuracy Time period [min] Shaft speed Quasi-steady-state filter 1r / min 15 Ship heading 2 degrees 0.1 degrees 30 water temperature 0.5℃ 0.1℃ 60 Relative wind speed 15% average wind speed (m / s) 0.1 m / s 30 Relative wind direction 10 degrees 1 degree 60 Significant wave height 0.15 meters 0.01 meter 30 Primary relative wave direction 10 degrees 1 degree 60 Primary wave cycle 0.5s 0.1s 60 Ground speed 0.1 m / s 0.1 m / s 30 Underwater speed 0.1 m / s 0.1 m / s 30

[0066] Step 1013: determining a standard deviation of environmental data based on the preset sliding window and the initial environmental data; and determining a standard deviation of ship performance data based on the preset sliding window and the initial ship performance data.

[0067] Specifically, the initial ship performance data is a data sequence collected by various sensors in the acquisition device. This data exhibits time series characteristics, meaning it is arranged in chronological order. Next, an appropriate window size is selected. The window size should not be too large, otherwise it will include excessive non-stationary data, affecting the assessment of local stability; nor should it be too small, otherwise it will not fully capture the statistical characteristics of the data. This is generally determined based on the data characteristics and analysis objectives. Preliminary window time periods are shown in Table 2. Next, the step size for each sliding window is determined. A smaller step size allows for more detailed observation of data changes, but increases computational complexity; a larger step size may overlook some data details. Typically, a step size related to the window size is chosen, such as 1 / 4 or 1 / 2 of the window size. Next, relevant statistics are calculated for the data within each sliding window. Commonly used statistics include the mean, variance, and standard deviation.

[0068] Specifically, starting from the starting point of the initial environmental data or initial ship performance data, the standard deviation within a preset sliding window is calculated. Standard deviation is an important indicator of data volatility; a smaller standard deviation indicates more stable data. Taking the shaft speed in Table 2 as an example, the corresponding preset sliding window size is 15 minutes. Starting from the starting point within the acquired shaft speed data set, the standard deviation of the data within the window from the first to the fifteenth shaft speed is calculated. The standard deviations of other parameters in the initial environmental data and initial ship performance data are calculated similarly. The standard deviations of the environmental data (including the standard deviations of various parameter data) and the ship performance data (including the standard deviations of various parameter data) can be calculated.

[0069] Step 1014: obtaining stable environmental data according to the environmental data standard deviation and a preset environmental standard deviation limit;

[0070] Specifically, the calculated standard deviation is compared with a preset standard deviation limit. If the calculated standard deviation is less than or equal to the preset standard deviation limit, the data within that window is stable and can be considered stable environmental data. Taking the water temperature in Table 2 as an example, if the standard deviation within a window (corresponding to a window size of 60) is 0.1°C, which is less than the preset standard deviation limit of 0.5°C, the data within that window can be considered stable environmental data. By sliding the window forward (or backward) by the time interval of one data point (for example, one minute for one data point per minute), the process of calculating the standard deviation and comparing the standard deviation with the preset standard deviation limit is repeated until the entire data set is processed. This process can be used to obtain stable environmental data for other parameters in the environmental data. All stable data can be considered stable environmental data. It should be noted that the preset environmental standard deviation limit includes the preset standard deviation limit corresponding to each parameter in the environmental data, such as the preset standard deviation limit corresponding to water temperature is 0.5°C, the preset standard deviation limit corresponding to relative wind speed is 15% of the average wind speed (m / s), etc.

[0071] Step 1015: obtaining stable ship performance data according to the ship performance data standard deviation and a preset ship performance standard deviation limit;

[0072] Specifically, the calculated standard deviation of the ship performance data is compared with the corresponding preset standard deviation limit. If the calculated standard deviation is less than or equal to the preset standard deviation limit, the data within that window is stable and can be considered stable ship performance data. Taking the ship heading in the ship performance data in Table 2 as an example, if the standard deviation within a window (corresponding to a window size of 30) is 1, which is less than the preset standard deviation limit of 2 degrees, the data within that window can be considered stable ship performance data. By sliding the window forward (or backward) by the time interval of one data point (for example, one minute for one data point per minute), and repeating the steps of calculating the standard deviation and comparing the standard deviation with the preset standard deviation limit to obtain stable data, stable ship performance data can be obtained until the entire data set is processed. Similarly, stable data for different parameters in the ship performance data can be obtained, and all stable data can be considered stable ship performance data. The preset standard deviation limits for shaft speed and ship heading in Table 2 can be set according to the requirements of the quasi-steady-state filter. It should be noted that the preset standard deviation limits for ship performance include the preset standard deviation limits corresponding to each parameter in the ship performance data, such as the preset standard deviation limit for ship heading is 2 degrees, the preset standard deviation limit for ground speed is 0.1 m / s, and so on.

[0073] Step 1016: Obtain target environment data and target ship performance data according to the stable environment data, the stable ship performance data, and a preset filtering standard.

[0074] Specifically, to eliminate the impact of special circumstances, such as steering and shallow water effects, and to ensure data stability, data filtering is required. Data that does not meet the preset filtering criteria can be deleted, and the remaining data is used as the target environment data and target ship performance data. For example, for water depth parameters in stable environment data, those less than or equal to 80 meters are deleted. For the difference parameter between underwater speed and ground speed in stable ship performance data, those that do not meet the difference of 0.5 knots are deleted.

[0075] Table 3 shows the preset filtering criteria for some environmental data and some ship performance data:

[0076] Table 3 Preset filtering criteria

[0077] parameter Restrictions (preset filter criteria) water depth >80 meters Water speed >11.54 & <15.2 wind speed <7.9 m / s Relative wind direction (0 and 360 degrees are headwind) <70 degrees & (110, 250) degrees & >290 degrees Significant wave height <3 meters Main wave direction (0 and 360 degrees represent top waves) <65 degrees & (115, 245) degrees > 295 degrees Difference between underwater speed and ground speed 0.5 section

[0078] In an optional embodiment of the present invention, step 103 includes:

[0079] Based on the target ship performance data and 、 Determine actual delivered fuel consumption;

[0080] in, is the actual delivered fuel consumption rate, is the shaft power in the target ship performance data, Q is the torque in the target ship performance data, PRM is the shaft revolutions in the target ship performance data, FC is the fuel consumption, is the transmission efficiency of the shaft in the target ship performance data, and T is the measurement time.

[0081] Here, the measurement time T, fuel consumption FC, and transmission system power All can be measured. Transmission efficiency of the shaft It is usually set to 0.99, depending on the location of the sensor. If it is close to the propeller, set it to 1.00. In reality, it is usually on the intermediate shaft, so set it to 0.99.

[0082] In an optional embodiment of the present invention, step 104 includes:

[0083] Step 1041, based on the target environment data and , determine the resistance caused by the environment;

[0084] Step 1042: Based on the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate;

[0085] in, ;in, is the drag caused by the environment, including wind, waves, and drag changes caused by temperature, is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, It is the water speed in the target ship performance data. It is the speed of the ship relative to the water and can be directly measured using a Doppler velocimeter or an electromagnetic velocimeter. It is the total efficiency of the target ship in the performance data, including hull efficiency, relative rotation efficiency and ship open water efficiency, which can be obtained from the ship model test. , is the hull efficiency, is the rotational efficiency, is the open water efficiency, It is the fuel consumption caused by the change of resistance. is the correction power of the environment.

[0086] Specifically, the purpose of calculating environmentally corrected fuel consumption is to eliminate the effects of weather such as waves, wind, and water temperature from the total resistance.

[0087] Among them, the method for determining the resistance caused by irregular waves can be carried out in accordance with ITTC7.5-02-07-02.2, in which sea state maintenance tests are conducted in regular waves of constant wave height or steepness, different wavelengths and directions, and different speeds. Irregular waves can be expressed as a linear superposition of regular wave components. Therefore, the average resistance increase of short-peak irregular waves Raw can be calculated by linearly superposing the directional wave spectrum E and the regular wave average resistance increase response function Rwave. The resistance caused by irregular waves should use a cleaning threshold to remove high power contributions from the increased resistance in the waves. When the waves are very high, the additional resistance in the waves will also be large, and the uncertainty of the wave resistance model will also be large. Therefore, a wave resistance threshold can be set. If the power caused by wave resistance accounts for more than 20% of the total power or the wave height exceeds 3m, it is considered that the data needs to be eliminated.

[0088] The resistance caused by wind It can be calculated by the following formula:

[0089] ;

[0090] in, is the resistance caused by the wind, is the air density, is the wind resistance coefficient, It's the wind direction. is the maximum cross-sectional area exposed to the wind, is the relative wind speed, 0 means headwind, It is the ground speed.

[0091] The resistance caused by temperature can be calculated by the following formula:

[0092] ;

[0093] in, is the resistance caused by temperature in the target environment data, is the total resistance at reference water temperature and reference water density, is the density of seawater at the actual water temperature, is the density of seawater at the reference temperature, , is the frictional resistance at the actual water temperature and actual water density, is the friction coefficient at reference water temperature and reference water density, is the friction coefficient at actual water temperature and actual water density, is the roughness margin related to the Reynolds number corresponding to the actual water temperature and salinity, is the roughness margin associated with the Reynolds number corresponding to the reference water temperature and salinity.

[0094] In order to reduce uncertainty and complexity, the influence of other factors, such as trim, is ignored because the actual power change it brings is very small. The power change caused by shallow water effect and steering is filtered out in data preprocessing and is not taken into account.

[0095] In an optional embodiment of the present invention, step 105 includes:

[0096] Step 1051, receiving ship model data and sea trial data;

[0097] Specifically, the ship model data is the data obtained from the ship model test in the water tank based on the ship model designed and manufactured with the geometry similar to the actual ship. The ship model data may include the key parameters such as the speed, thrust, torque of the ship model corresponding to different loading conditions, such as light ballast, heavy ballast, full load and full load conditions of structural draft. It may also include water flow speed, water depth, wind direction, wave conditions, etc. (such as calm water surface with no wind and waves and water temperature of 15°C); the sea trial data is the data such as speed, thrust, torque, water flow speed, water depth, wind direction, wave conditions, etc. corresponding to the ship model test collected during the actual ship sea trial.

[0098] Step 1052: correcting the ship model data according to the difference between the ship model data and the sea trial data to obtain corrected ship model data;

[0099] Specifically, according to the ship model data and The effective power of the ship model is calculated respectively, where is the effective power of the ship model, is the thrust in the ship model data (which can be calculated from the torque and propeller speed in the ship model data), is the propeller efficiency in the ship model data. With the speed as the horizontal axis and the effective power as the vertical axis, the power curve under different loading conditions is drawn; according to ,in, is the corrected power, is the effective power of the ship model, is the effective power during the sea trial (which can be obtained by multiplying the thrust in the sea trial data by the propeller efficiency).

[0100] Among them, model conditions refer to the water flow velocity, water depth, wind direction, wave conditions, etc. in the model data; trial sailing conditions refer to the water flow velocity, water depth, wind direction, wave conditions, etc. in the trial sailing data; actual conditions refer to the water flow velocity, water depth, wind direction, wave conditions, etc. in the target data (expected environmental state data).

[0101] Step 1053: Determine a reference delivery fuel consumption rate based on the corrected ship model data and the sea trial data.

[0102] Specifically, the speed and load capacity are obtained from the corrected ship model data and sea trial data; then The reference delivery fuel consumption rate is calculated, where is the reference delivery fuel consumption rate, 、 、 are regression coefficients, V is the speed, W is the load (in terms of displacement express).

[0103] In an optional embodiment of the present invention, step 106 includes:

[0104] According to the reference delivery fuel consumption rate, the actual delivery fuel consumption rate, the environmental correction fuel consumption rate and , determine the comprehensive energy efficiency index of ships;

[0105] Among them, SCEI is the ship comprehensive energy efficiency index, is the actual delivered fuel consumption rate, is the environmentally corrected fuel consumption, is the reference delivered fuel consumption rate.

[0106] Specifically, the Ship Comprehensive Energy Efficiency Index (SCEI) refers to the power ratio required by an operating vessel, relative to a clean hull and polished propeller, at a specific draft and speed. Calculated using the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate, the SCEI accounts for and adjusts for relevant operational and weather factors, eliminating the influence of environmental and operational factors during actual testing, thereby improving the accuracy of subsequent assessments of a vessel's actual performance.

[0107] In an optional embodiment of the present invention, step 107 includes:

[0108] Step 1071: Obtaining a ship performance level according to the ship comprehensive energy efficiency index and a preset index threshold;

[0109] Specifically, the preset index threshold can be obtained based on the ship comprehensive energy efficiency index of multiple ships. As the ship's operating time increases, the ship comprehensive energy efficiency index will become higher. By comparing the ship comprehensive energy efficiency index with the preset index threshold, the ship performance level can be obtained. In a specific embodiment, as shown in Table 4, the ship performance level corresponding to the preset index threshold is shown. According to this table, the ship performance level corresponding to the ship comprehensive energy efficiency index can be found, so that the ship performance can be evaluated according to the level later. If the ship comprehensive energy efficiency index is 5, the obtained ship performance level is good. If the ship comprehensive energy efficiency index is 10, the obtained ship performance level is poor. It should be noted that this embodiment is only for illustration. In specific implementation, other preset index thresholds and corresponding ship performance levels can also be set.

[0110] Table 4 Ship performance levels corresponding to preset index thresholds

[0111] Preset index threshold Ship performance level 5 good 10 Difference

[0112] Step 1072: Obtain a ship maintenance plan based on the ship performance level and pre-stored ship maintenance data;

[0113] Specifically, the pre-stored ship maintenance data may include different ship maintenance plans implemented for different ship performance levels over a historical period. Based on the ship performance level, the corresponding ship maintenance plan is retrieved from the pre-stored ship maintenance data. In one specific embodiment, if the ship performance level is good, only routine maintenance is required; if the ship performance level is poor, the hull and propeller cleaning are required to improve ship performance. It should be noted that the ship performance levels and ship maintenance plans in Table 5 are for illustrative purposes only; other ship performance levels and corresponding ship maintenance plans may also be set during implementation.

[0114] Table 5 Ship performance levels corresponding to preset index thresholds

[0115] Ship performance level Ship maintenance solutions good Daily maintenance Difference Hull and propeller cleaning

[0116] Step 1073: Evaluate the ship performance according to the ship comprehensive energy efficiency index, the preset index threshold, the ship performance level, and the ship maintenance plan to obtain a ship performance evaluation result.

[0117] Specifically, the evaluation result can be a ship performance evaluation report, which includes the ship's comprehensive energy efficiency index, preset index threshold, ship performance level, and ship maintenance plan. This allows users to intuitively and comprehensively understand the process and data basis for evaluating ship performance, thereby improving user satisfaction. During implementation, a template for the ship performance evaluation report can be created, and the ship's comprehensive energy efficiency index, preset index threshold, ship performance level, and ship maintenance plan can be entered into the template to form the final evaluation result, which will help improve the efficiency of the method.

[0118] A specific embodiment of the ship performance evaluation method proposed in the embodiment of the present invention includes:

[0119] Step 111, obtaining data;

[0120] By installing various sensors or other data collection tools and equipment on the ship, the initial environmental data and initial ship performance data of the ship during operation are collected. The data can be collected according to fixed periods or sections. The data within a period or section are taken as a group, and the comprehensive energy efficiency index of the ships in the group is calculated. Finally, the average value of the comprehensive energy efficiency index of all groups is taken as the final comprehensive energy efficiency index to evaluate the ship performance.

[0121] Among them, the initial environmental data may include water temperature, relative wind speed, relative wind direction, significant wave height, primary relative wave direction, primary wave period, water depth, water speed, wind speed, wave direction, resistance caused by irregular waves, resistance caused by wind, resistance caused by temperature, etc.; the initial ship performance data may include shaft speed, ship heading, ground speed, underwater speed, shaft power, torque, shaft transmission efficiency, water speed, total ship efficiency, etc.

[0122] Step 112, data preprocessing;

[0123] Because different data have varying degrees of importance, to reduce the uncertainty of subsequent SCEI calculations, data preprocessing is performed with considerations of data accuracy, sampling frequency, and processing. For highly important data such as ship speed and shaft power, higher requirements must be placed on data accuracy and sampling frequency. Furthermore, to ensure data quality, data should be as stable as possible. Therefore, a sliding window approach, as shown in Table 2, can be used to assess data stability and extract stable data. For relatively important parameters, simple standard deviation filtering can be employed, directly using a threshold to determine stability within the window period and filter the data. To eliminate the influence of special conditions, such as steering and shallow water effects, and to ensure data stability, physical filtering can be employed to eliminate data under more extreme conditions. For example, data can be filtered according to the preset filtering criteria shown in Table 3.

[0124] Step 113: Calculate the actual delivered fuel consumption rate ;

[0125] Actual delivered fuel consumption (AFC), also known as actual delivered power, is the actual power delivered by the propeller during operation. This power is composed of two components: one is the resistance consumption of the propulsion vessel and conventional ships (wind resistance and friction resistance in still water, calm water, and a water temperature of 15°C); the other is the increased resistance caused by objective uncertainties in wind, waves, and water temperature, which results in additional consumption and must be eliminated.

[0126] The actual delivered fuel consumption rate is usually measured on board an operating ship, usually by measuring the shaft power. , the unit is kW, which can be measured in combination with torque and speed. The unit is kN·m, combined with the shaft speed RPM / RPS per minute or per second, through Calculate the shaft power .

[0127] Shaft transmission efficiency It is usually set to 0.99, depending on the location of the sensor. If it is close to the propeller, set it to 1.00. In reality, it is usually on the intermediate shaft, so set it to 0.99.

[0128] Torque The measurement can refer to the strain sensor, and the shaft speed (RPM) is required to be revolutions per minute (RPM) or revolutions per second (RPS). These two data are generally available on board. These two factors directly determine The accuracy of the data is high, so the data quality requirements are relatively high. When cleaning the data, special attention should be paid to the torque. , data with high RPM change rate.

[0129] By measuring the shaft power , measurement time T, fuel consumption FC and transmission efficiency Calculate actual delivered fuel consumption :

[0130] .

[0131] Step 114, calculate the environmental corrected fuel consumption rate ;

[0132] The purpose of environmental correction is to eliminate the influence of weather such as waves, wind, and water temperature from the total resistance. The environmental correction power is: based on the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate;

[0133] in, ;

[0134] in, It is the resistance caused by the environment. is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, is the water speed in the target ship performance data, is the total ship efficiency in the target ship performance data, It is the fuel consumption caused by the change of resistance. is the correction power of the environment.

[0135] Among them, the method for determining the resistance caused by irregular waves can be carried out in accordance with ITTC7.5-02-07-02.2, in which sea state maintenance tests are conducted in regular waves of constant wave height or steepness, different wavelengths and directions, and different speeds. Irregular waves can be expressed as a linear superposition of regular wave components. Therefore, the average resistance increase of short-peak irregular waves Raw can be calculated by linearly superposing the directional wave spectrum E and the regular wave average resistance increase response function Rwave. The resistance caused by irregular waves should use a cleaning threshold to remove high power contributions from the increased resistance in the waves. When the waves are very high, the additional resistance in the waves will also be large, and the uncertainty of the wave resistance model will also be large. Therefore, a wave resistance threshold can be set. If the power caused by wave resistance accounts for more than 20% of the total power or the wave height exceeds 3m, it is considered that the data needs to be eliminated.

[0136] The resistance caused by wind can be calculated by the following formula:

[0137] ;

[0138] in, is the resistance caused by the wind, is the air density, is the wind resistance coefficient, It's the wind direction. is the maximum cross-sectional area exposed to the wind, is the relative wind speed, 0 means headwind, It is the ground speed.

[0139] The resistance caused by temperature can be calculated by the following formula:

[0140] ;

[0141] in, is the resistance caused by temperature in the target environment data, is the total resistance at reference water temperature and reference water density, is the density of seawater at the actual water temperature, is the density of seawater at the reference temperature, , is the frictional resistance at the actual water temperature and actual water density, is the friction coefficient at reference water temperature and reference water density, is the friction coefficient at actual water temperature and actual water density, is the roughness margin related to the Reynolds number corresponding to the actual water temperature and salinity, is the roughness margin associated with the Reynolds number corresponding to the reference water temperature and salinity.

[0142] Step 115: Calculate the reference delivery fuel consumption rate ;

[0143] The reference delivery fuel consumption rate is a very important basic data. This data is obtained through ship model tests and sea trials. It represents the ideal conditions for cleaning the hull and polishing the propeller. It also represents the ideal conditions for wind, waves, currents and temperature. The ideal state is calm water with no wind and no waves, and the water temperature is 15°C. The ship model data is corrected using the sea trial data to obtain the power under several different speeds and loading conditions. For the actual loading and draft, the interpolation method is used to obtain. From the acquisition of the data, it can be seen that the more operating conditions calculated in the ship model test, the more stable the sea trial conditions, and the higher the quality of the sea trial data, the lower the uncertainty and the higher the data validity. Therefore, at least four loading conditions should be included, preferably including ballasted conditions, loaded conditions, and some intermediate conditions.

[0144] Step 116, calculating the ship comprehensive energy efficiency index SCEI;

[0145] Enter the calculated reference delivery fuel consumption rate, actual delivery fuel consumption rate and environmental correction fuel consumption rate into the formula , and obtain the ship comprehensive energy efficiency index SCEI.

[0146] Step 117: Ship performance evaluation.

[0147] When evaluating ship performance, you first need to determine the ship performance level based on the ship's comprehensive energy efficiency index and the preset index threshold, then determine the corresponding ship maintenance plan based on the level, and finally fill the ship's comprehensive energy efficiency index, preset index threshold, ship performance level and ship maintenance plan into the template according to the preset template to form the final evaluation results for user convenience.

[0148] The ship performance evaluation method proposed in the embodiment of the present invention eliminates the influence of environmental, operational and other factors in actual testing by calculating and adjusting relevant operational factors and weather influences, and reflects the actual performance of the ship. The ship comprehensive energy efficiency index (SCEI) reflects the changes in ship performance more accurately by correcting relevant operational and weather influences, isolating the technical performance of the ship, and is of great significance to ship energy conservation and emission reduction. It is mainly reflected in: optimizing ship maintenance plans and reducing energy consumption: During the operation of the ship, the additional dirt generated by the hull and propeller leads to increased resistance and additional power, resulting in a decline in performance. The SCEI indicates the degree of performance degradation during operation. Keeping the hull and propeller smooth and clean can improve operational efficiency and save fuel. Therefore, the value of the SCEI can be used as a basis for whether the ship needs to clean the hull and propeller.

[0149] In another specific embodiment, the trained fuel consumption rate prediction model is used to obtain the fuel consumption rate after eliminating the environmental impact, that is, and , and obtain the ship comprehensive energy efficiency index SCEI.

[0150] Among them, the environmental data such as wind, waves, water temperature, density, etc. of the fused data are first reset to the baseline value under the still water state, and all types of resistance increase are set to 0; then the reset data is input into the fuel consumption rate prediction model, and the fuel consumption rate after eliminating the environmental impact is output.

[0151] The training process of the fuel consumption rate prediction model includes:

[0152] The pre-processed ship static data, meteorological and sea condition data, ship navigation data and various resistance increase data are fused and processed. The meteorological and sea condition data, ship navigation data and various resistance increase data are matched according to time and longitude and latitude. The ship static data is matched according to the ship MMSI number (Maritime Mobile Service Identification Code) or IMO number (International Maritime Organization Identification Code). Finally, the ship static data, meteorological and sea condition data, ship navigation data and various resistance increase data are fused into a basic data as the training data for the preset network model.

[0153] Determine the neural network's architecture, including the number of neurons in the input, hidden, and output layers. The number of neurons in the input layer is typically equal to the number of independent variables after PLSR (partial least squares regression) transformation, and the number of neurons in the output layer is equal to the number of dependent variables. The number of hidden layers and neurons needs to be adjusted and optimized based on the specific problem.

[0154] Select an appropriate activation function, such as Sigmoid (S-shaped function) or Tanh (hyperbolic tangent function). Determine an optimization algorithm, such as Stochastic Gradient Descent (SGD) or Adagrad (adaptive gradient algorithm), to update the neural network weights. Then, input the training set independent variables and the corresponding dependent variables into the pre-set network model for training. During training, the weights of the neural network in the pre-set network model are continuously adjusted based on the selected optimization algorithm to minimize the loss function. Common loss functions include mean squared error (MSE) and cross entropy loss.

[0155] Use the test set to evaluate the trained fuel consumption rate prediction model and calculate the evaluation index. When the evaluation index meets the preset index, the training ends and the fuel consumption rate prediction model is obtained. The evaluation index can be the root mean square error (RMSE) or the mean absolute error (MAE) or the coefficient of determination ( ) to measure the prediction performance of the model. Figure 2 As shown, an embodiment of the present invention provides a ship performance evaluation device 200, comprising:

[0156] An acquisition module 201 is used to acquire target environment data and target ship performance data during ship operation;

[0157] The processing module 202 is used to determine the actual delivery fuel consumption rate based on the target ship performance data; determine the corrected fuel consumption rate for the environment based on the target environment data and the target ship performance data; determine the reference delivery fuel consumption rate based on the received ship model data and sea trial data; determine the ship's comprehensive energy efficiency index based on the reference delivery fuel consumption rate, the actual delivery fuel consumption rate and the corrected fuel consumption rate for the environment; and evaluate the ship's performance based on the ship's comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result.

[0158] Optionally, target environment data and target ship performance data are obtained during ship operation, including:

[0159] Get the preset sliding window;

[0160] Determining a standard deviation of environmental data based on the preset sliding window and the initial environmental data;

[0161] determining a standard deviation of the ship performance data based on the preset sliding window and the initial ship performance data;

[0162] Obtaining stable environmental data according to the environmental data standard deviation and a preset environmental standard deviation limit;

[0163] Obtaining stable ship performance data according to the ship performance data standard deviation and a preset ship performance standard deviation limit;

[0164] Target environment data and target ship performance data are obtained according to the stable environment data, the stable ship performance data and preset filtering criteria.

[0165] Optionally, determining the actual delivered fuel consumption rate based on the target ship performance data includes:

[0166] Based on the target ship performance data and 、 Determine actual delivered fuel consumption;

[0167] in, is the actual delivered fuel consumption rate, is the shaft power in the target ship performance data, Q is the torque in the target ship performance data, PRM is the shaft revolutions in the target ship performance data, FC is the fuel consumption, is the transmission efficiency of the shaft in the target ship performance data, and T is the measurement time.

[0168] Optionally, determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data includes:

[0169] According to the target environment data and , determine the resistance caused by the environment;

[0170] According to the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate;

[0171] in, ;

[0172] in, It is the resistance caused by the environment. is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, is the water speed in the target ship performance data, is the total ship efficiency in the target ship performance data, It is the fuel consumption caused by the change of resistance. is the correction power of the environment.

[0173] Optionally, based on the received ship model data and sea trial data, determine the reference delivery fuel consumption rate, including:

[0174] Receive ship model data and sea trial data;

[0175] Correcting the ship model data according to the difference between the ship model data and the sea trial data to obtain corrected ship model data;

[0176] A reference delivery fuel consumption rate is determined based on the corrected ship model data and the sea trial data.

[0177] Optionally, determining a comprehensive energy efficiency index of a ship according to the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate includes:

[0178] According to the reference delivery fuel consumption rate, the actual delivery fuel consumption rate, the environmental correction fuel consumption rate and , determine the comprehensive energy efficiency index of ships;

[0179] Among them, SCEI is the ship comprehensive energy efficiency index, is the actual delivered fuel consumption rate, is the environmentally corrected fuel consumption, is the reference delivered fuel consumption rate.

[0180] Optionally, the ship performance is evaluated according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result, including:

[0181] Obtaining a ship performance level according to the ship comprehensive energy efficiency index and a preset index threshold;

[0182] Obtaining a ship maintenance plan based on the ship performance level and pre-stored ship maintenance data;

[0183] The ship performance is evaluated according to the ship comprehensive energy efficiency index, the preset index threshold, the ship performance level, and the ship maintenance plan to obtain a ship performance evaluation result.

[0184] The ship performance evaluation device proposed in an embodiment of the present invention obtains target environmental data and target ship performance data during ship operation, determines the actual delivered fuel consumption rate, the reference delivered fuel consumption rate, and the environmentally corrected fuel consumption rate, and calculates the ship's comprehensive energy efficiency index. Finally, the ship's performance is evaluated based on the ship's comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result. This eliminates the influence of environmental, operational, and other factors in actual testing, can reflect the actual performance of the ship, and is of great significance to ship energy conservation and emission reduction.

[0185] It should be noted that the device is a device corresponding to the above method, and all implementations in the above method embodiment are applicable to the embodiment of the device and can achieve the same technical effects, which will not be described in detail in this embodiment.

[0186] An embodiment of the present invention further provides a computing device comprising: a processor and a memory storing a computer program. When the computer program is executed by the processor, the computer program performs the method described in any of the above embodiments. All implementations in the above method embodiments are applicable to the embodiments of this device and can achieve the same technical effects. These are not further described in this embodiment.

[0187] An embodiment of the present invention further provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the method described in any of the above embodiments. All implementations in the above method embodiments are applicable to the embodiments of the device and can achieve the same technical effects. These are not further described in this embodiment.

[0188] It should be noted that, in the apparatus and method of the present invention, it is apparent that each component or step can be decomposed and / or recombined. Such decomposition and / or recombination should be considered equivalent solutions of the present invention. Furthermore, the steps of performing the above series of processes can naturally be performed in chronological order according to the order described, but do not necessarily need to be performed in chronological order. Certain steps can be performed in parallel, interleaved, or independently of each other.

[0189] It should be noted that, in the above embodiments, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be pointed out that the scope of the methods and devices in the implementation methods of the above embodiments is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0190] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for evaluating ship performance, characterized in that: include: Acquire target environment data and target ship performance data during ship operation; Determine the actual delivered fuel consumption rate based on the target ship performance data; determining an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data; Determine the reference delivery fuel consumption rate based on the received ship model data and sea trial data; determining a comprehensive energy efficiency index of the ship based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate; Evaluate the ship performance according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result; The actual delivered fuel consumption rate is determined based on the target ship performance data, including: Based on the target ship performance data and 、 Determine actual delivered fuel consumption; in, is the actual delivered fuel consumption rate, is the shaft power in the target ship performance data, Q is the torque in the target ship performance data, PRM is the shaft revolutions in the target ship performance data, FC is the fuel consumption, is the transmission efficiency of the shaft in the target ship performance data, and T is the measurement time; The step of determining the corrected fuel consumption rate for the environment based on the target environment data and the target ship performance data includes: According to the target environment data and , determine the resistance caused by the environment; According to the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate; in, ; in, It is the resistance caused by the environment. is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, is the water speed in the target ship performance data, is the total ship efficiency in the target ship performance data, It is the fuel consumption caused by the change of resistance. is the correction power of the environment; The ship comprehensive energy efficiency index is determined based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate, including: According to the reference delivery fuel consumption rate, the actual delivery fuel consumption rate, the environmental correction fuel consumption rate and , determine the comprehensive energy efficiency index of ships; Among them, SCEI is the ship comprehensive energy efficiency index, is the actual delivered fuel consumption rate, is the environmentally corrected fuel consumption, is the reference delivered fuel consumption rate.

2. The method for evaluating ship performance according to claim 1, characterized in that: Obtain target environmental data and target ship performance data during ship operation, including: Get the preset sliding window; Determining a standard deviation of environmental data based on the preset sliding window and the initial environmental data; determining a standard deviation of the ship performance data based on the preset sliding window and the initial ship performance data; Obtaining stable environmental data according to the environmental data standard deviation and a preset environmental standard deviation limit; Obtaining stable ship performance data according to the ship performance data standard deviation and a preset ship performance standard deviation limit; Target environment data and target ship performance data are obtained according to the stable environment data, the stable ship performance data and preset filtering criteria.

3. The method for evaluating ship performance according to claim 1, wherein: Determine the reference delivery fuel consumption rate based on the received ship model data and sea trial data, including: Receive ship model data and sea trial data; Correcting the ship model data according to the difference between the ship model data and the sea trial data to obtain corrected ship model data; A reference delivery fuel consumption rate is determined based on the corrected ship model data and the sea trial data.

4. The method for evaluating ship performance according to claim 1, wherein: The ship performance is evaluated according to the ship comprehensive energy efficiency index and the preset index threshold, and a ship performance evaluation result is obtained, including: Obtaining a ship performance level according to the ship comprehensive energy efficiency index and a preset index threshold; Obtaining a ship maintenance plan based on the ship performance level and pre-stored ship maintenance data; The ship performance is evaluated according to the ship comprehensive energy efficiency index, the preset index threshold, the ship performance level, and the ship maintenance plan to obtain a ship performance evaluation result.

5. A device for evaluating ship performance, characterized in that: include: An acquisition module is used to acquire target environment data and target ship performance data during ship operation; a processing module, configured to determine an actual delivered fuel consumption rate based on the target ship performance data; determine an environmentally corrected fuel consumption rate based on the target environmental data and the target ship performance data; determine a reference delivered fuel consumption rate based on the received ship model data and sea trial data; and determine a comprehensive ship energy efficiency index based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate; Evaluate the ship performance according to the ship comprehensive energy efficiency index and a preset index threshold to obtain a ship performance evaluation result; The actual delivered fuel consumption rate is determined based on the target ship performance data, including: Based on the target ship performance data and 、 Determine actual delivered fuel consumption; in, is the actual delivered fuel consumption rate, is the shaft power in the target ship performance data, Q is the torque in the target ship performance data, PRM is the shaft revolutions in the target ship performance data, FC is the fuel consumption, is the transmission efficiency of the shaft in the target ship performance data, and T is the measurement time; The step of determining the corrected fuel consumption rate for the environment based on the target environment data and the target ship performance data includes: According to the target environment data and , determine the resistance caused by the environment; According to the resistance caused by the environment, the target ship performance data and , determine the environmentally corrected fuel consumption rate; in, ; in, It is the resistance caused by the environment. is the resistance caused by irregular waves in the target environment data, is the resistance caused by the stroke in the target environment data, is the resistance caused by temperature in the target environment data, is the environmentally corrected fuel consumption, is the water speed in the target ship performance data, is the total ship efficiency in the target ship performance data, It is the fuel consumption caused by the change of resistance. is the correction power of the environment; The ship comprehensive energy efficiency index is determined based on the reference delivered fuel consumption rate, the actual delivered fuel consumption rate, and the environmentally corrected fuel consumption rate, including: According to the reference delivery fuel consumption rate, the actual delivery fuel consumption rate, the environmental correction fuel consumption rate and , determine the comprehensive energy efficiency index of ships; Among them, SCEI is the ship comprehensive energy efficiency index, is the actual delivered fuel consumption rate, is the environmentally corrected fuel consumption, is the reference delivered fuel consumption rate.

6. A computing device, characterized in that include: A processor and a memory storing a computer program, wherein when the computer program is executed by the processor, the method according to any one of claims 1 to 4 is performed.

7. A computer-readable storage medium, characterized in that The device stores instructions, which, when executed on a computer, enable the computer to execute the method according to any one of claims 1 to 4.

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