A method for estimating the position and gamma value of an ocean radioactive drifting buoy

Abstract

The present invention discloses a method for estimating the position and gamma value of a marine radioactive drifting buoy. The buoy receives positioning data and detects the radioactive nuclides in the seawater at the position during the drifting process in the seawater, and generates sampling data including the sampling time, longitude and latitude values ​​and gamma values ​​of the sampling points; the estimation method comprises: finding the sampling points where the longitude and latitude values ​​and gamma values ​​are missing in the sampling data as estimation points; extracting N sampling points with real longitude and latitude values ​​before and after the estimation points at the sampling time, and using them to perform fitting estimation on the longitude and latitude values ​​of the estimation points; extracting M sampling points with real gamma values ​​before and after the estimation points at the sampling time, and using them to perform fitting estimation on the gamma values ​​of the estimation points. The present invention can quickly fit and estimate the longitude and latitude values ​​and gamma values ​​of the missing positions according to the drifting law of the buoy and the changing trend of the radioactive nuclides at the surrounding sampling points, and provide complete seawater radioactive nuclide monitoring data for operators.

Description

Technical Field

[0001] The invention belongs to the technical field of marine environment monitoring, and in particular, relates to a method for processing positioning data of a marine radioactive drifting buoy and gamma data collected therefrom. Background Art

[0002] The marine radioactive drifting buoy is a device used to monitor radioactive nuclides in seawater. In actual use, the marine radioactive drifting buoy is usually deployed in the open sea, drifting with the ocean current, and positioning through communication with the satellite system to obtain the longitude and latitude values ​​of each drifting point, and at the same time detect the radioactive nuclides in the seawater at each drifting point, and generate sampling data including the sampling time, the longitude and latitude values ​​of the sampling point, and the gamma value of the sampling point, which is sent to the monitoring center on the shore through the satellite system, so that the shore workers can remotely monitor the distribution and change trend of radioactive nuclides in seawater and quickly warn.

[0003] The actual marine field monitoring environment is complex and changeable, with many interference factors. When the marine radioactive drifting buoy is affected by severe sea conditions at a certain sampling point, it will interfere with the reception of its positioning data and the detection of radioactive nuclides. The phenomenon is that the longitude and latitude values ​​and gamma values ​​may not be detected at a certain sampling point, resulting in incomplete data collection, which will affect the overall analysis and prediction of the distribution of radioactive nuclides in seawater by operators.

[0004] In view of this, how to combine the drifting law of ocean radioactive drifting buoys and the changing trend of radioactive nuclides at surrounding sampling points to predict and estimate the lost longitude and latitude values ​​and gamma data of a certain sampling point in order to obtain complete monitoring data is an important topic in the development of domestic marine radioactivity measurement. Summary of the invention

[0005] The purpose of the present invention is to provide a method for estimating the position and gamma value of an ocean radioactive drifting buoy, which can quickly fit and estimate the longitude and latitude values ​​and gamma values ​​of missing positions according to the drifting law of the ocean radioactive drifting buoy and the change trend of radionuclides at surrounding sampling points, so as to provide complete seawater radionuclide monitoring data for operators.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0007] A method for estimating the position and gamma value of a marine radioactive drifting buoy, wherein the marine radioactive drifting buoy receives positioning data and detects radioactive nuclides in the seawater at the position during drifting in the seawater, and generates sampling data including the sampling time, longitude and latitude values ​​and gamma value of the seawater radioactive nuclides of the sampling point; wherein the estimation method comprises:

[0008] Find the sampling points where the latitude, longitude and gamma values ​​are missing in the sampled data as the estimated point A x ;

[0009] Extract the sampling time at the estimated point A x The N sampling points before and after the time with real longitude and latitude values ​​are recorded as A1, A2, ..., A 2N , used to estimate point A x The longitude and latitude values ​​of are estimated;

[0010] Extract the sampling time at the estimated point A x The M sampling points with real gamma values ​​before and after are denoted as B1, B2, ..., B 2M , used to estimate point A x The gamma value of is estimated;

[0011] At the estimated point A x In the process of estimating the longitude and latitude values, 2N sampling points A1, A2, ..., A 2N The sampling time and longitude and latitude values ​​generate a fitting curve, and the estimated point A x Substitute the sampling time into the fitting curve and calculate the estimated point A x The latitude and longitude values ​​of

[0012] At the estimated point A x In the process of estimating the gamma value, according to 2M sampling points B1, B2, ..., B 2M With estimated point A x The distance is 2M, weights are assigned to the 2M sampling points, and the estimated point A is estimated according to the gamma values ​​of the 2M sampling points and their weights. x The gamma value of .

[0013] In some embodiments of the present application, in order to facilitate calculation, when substituting the sampling times of the 2N sampling points and the estimated points into the fitting curve formula, a reference time can be first determined, and the reference time should be earlier than the sampling time of the 2N sampling points; then, the difference between the sampling time of the 2N sampling points and the estimated points and the reference time is calculated, and the difference is used instead of the sampling time to substitute into the fitting curve formula to participate in the calculation, so as to simplify the calculation process.

[0014] In some embodiments of the present application, the estimated point A x The process of estimating the longitude and latitude values ​​specifically includes:

[0015] The 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and longitude values ​​into the least squares curve fitting formula jd=kt+b, calculate the values ​​of coefficients k and b, and generate the longitude fitting curve;

[0016] Estimated point A x Substitute the sampling time into the longitude fitting curve to calculate the estimated point A x The longitude value of

[0017] The 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and latitude values ​​into the least squares curve fitting formula wd=k't+b', calculate the values ​​of coefficients k' and b', and generate the latitude fitting curve;

[0018] Estimated point A x Substitute the sampling time into the latitude fitting curve to calculate the estimated point A x The latitude value of

[0019] Among them, jd represents the longitude value, wd represents the latitude value, and t represents the sampling time.

[0020] In some embodiments of the present application, in order to improve the accuracy of longitude and latitude estimation, the 2N sampling points A1, A2, ..., A 2N It is the sampling time distance from the estimated point A among the sampling points with real latitude and longitude values. x The sampling time of the 2N most recent sampling points.

[0021] In some embodiments of the present application, in order to improve the accuracy of gamma value estimation, the 2M sampling points B1, B2, ..., B 2M Among the sampling points with true gamma values, the sampling time is far from the estimated point A x The sampling time of the 2M sampling points most recent.

[0022] In some embodiments of the present application, the value of M is 2 or 3; and N is greater than or equal to M, which ensures that the gamma value estimation result is as accurate as possible while shortening the calculation time and improving the prediction efficiency.

[0023] In some embodiments of the present application, the estimated point A x The process of estimating the gamma value includes:

[0024] Using the estimated point A x and the 2M sampling points B1, B2, ..., B 2M The latitude and longitude values ​​of each sampling point B1, B2, ..., B 2M With estimated point A x The distances between them are denoted as d1, d2, ..., d 2M ;

[0025] According to 2M distances d1, d2, ..., d 2MThe 2M sampling points B1, B2, ..., B 2M Assign weights;

[0026] Calculate the 2M sampling points B1, B2, ..., B 2M The sum of the gamma value and its weight is used as the estimated point A x The gamma value of .

[0027] In some embodiments of the present application, when calculating each of the sampling points B1, B2, ..., B 2M With estimated point A x When the distance between each sampling point B1, B2, ..., B 2M The latitude and longitude values ​​of the estimated point A x Substitute the longitude and latitude values ​​into the following distance calculation formula to obtain:

[0028] d i =R*arccos[cos(Y1)*cos(Y2)*cos(X1-X2)+sin(Y1)*sin(Y2)]*π / 180;

[0029] Among them, d i Indicates sampling point B i With estimated point A x The distance between them; R is the radius of the earth; (X1, Y1) is the sampling point B i The longitude and latitude values ​​of the estimated point A. x The longitude and latitude values ​​of .

[0030] In some embodiments of the present application, for the 2M sampling points B1, B2, ..., B 2M When allocating weights, the 2M sampling points B1, B2, ..., B 2M The weight is negatively correlated with the 2M distances.

[0031] In some embodiments of the present application, the 2M sampling points B1, B2, ..., B 2M The weight distribution process can include:

[0032] Calculate the reciprocal sum of 2M distances:

[0033] Calculate sampling point B i Weight:

[0034] Compared with the prior art, the advantages and positive effects of the present invention are as follows: the method for estimating the position and gamma value of the marine radioactive drifting buoy of the present invention is not limited by the location of the drifting buoy, nor is it affected by the interference of the marine environment. It can quickly estimate the position of the marine radioactive drifting buoy at the sampling point and the gamma value of the radioactive nuclides in the seawater at that location, thereby overcoming the problem of occasional missing data commonly existing in marine radioactive drifting buoys, and can provide complete monitoring data for the overall analysis and prediction of the distribution of radioactive nuclides in seawater for operators.

[0035] Other features and advantages of the present invention will become more apparent after reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 It is an overall architecture diagram of an embodiment of a marine monitoring system;

[0038] Figure 2 It is a general flow chart of an embodiment of the method for estimating the position and gamma value of a marine radioactive drifting buoy proposed by the present invention;

[0039] Figure 3 It is a specific flow chart of an embodiment of a method for estimating the position of an ocean radioactive drifting buoy;

[0040] Figure 4 The present invention is a specific flow chart of an embodiment of a method for estimating the gamma value of radioactive nuclides in seawater. DETAILED DESCRIPTION

[0041] The specific implementation modes of the present invention are described in detail below with reference to the accompanying drawings.

[0042] The position and gamma value estimation method of this embodiment is based on the sampling data collected by the ocean radioactive drifting buoy, combined with the drifting law of the ocean radioactive drifting buoy and the gamma values ​​of the radioactive nuclides in the seawater at the surrounding sampling points, and performs fitting estimation of the missing data for the sampling points that have lost position information and gamma data, thereby forming complete monitoring data to make up for the defect that the ocean radioactive drifting buoy occasionally fails to detect position information and gamma data due to interference from the complex marine environment.

[0043] After being deployed in the open sea, the marine radioactive drifting buoy drifts with the current, uses the satellite system to locate, and regularly collects the gamma value of radioactive nuclides in the seawater, generates sampling data and sends it to the monitoring center on the shore through the satellite system. Figure 1 As shown, it can be provided to shoreside operators to complete the remote monitoring task of the marine environment.

[0044] The ocean radioactive drifting buoy of this embodiment generates sampling data which includes at least the sampling time of each sampling point; the physical position of the buoy drifting point at the sampling time, i.e., the longitude and latitude values; and the gamma value of the radioactive nuclides in the seawater at the drifting point.

[0045] The ocean radioactive drifting buoy sends the sampling data to the monitoring center at a regular interval. After receiving the sampling data, if the monitoring center finds that the longitude, latitude and gamma values ​​of some sampling points in the sampling data are missing, the position and gamma value estimation method of this embodiment can be used to quickly fit the longitude, latitude and gamma values ​​of the missing positions.

[0046] The estimation method of this embodiment mainly involves two parts: fitting estimation of longitude and latitude values ​​and fitting estimation of gamma values. Among them, the fitting estimation process of gamma values ​​depends on the longitude and latitude values ​​of the sampling points around the missing position. Therefore, it is necessary to first perform the fitting estimation process of longitude and latitude values ​​to estimate the position information of the sampling point where the data is missing, and then estimate the gamma value of the missing sampling point in combination with the estimated position information.

[0047] like Figure 2 As shown, the method for estimating the position and gamma value of a marine radioactive drifting buoy in this embodiment mainly includes the following processes:

[0048] S101, finding sampling points in the sampled data where the latitude, longitude and gamma values ​​are missing as estimation points.

[0049] In this embodiment, the latitude and longitude values ​​and gamma values ​​of all sampling points in the sampled data can be traversed to find sampling points with missing latitude and longitude values ​​and / or gamma values, and the sampling points are recorded as estimated points A. x , in order to distinguish it from other sampling points.

[0050] S102, extracting N sampling points with real latitude and longitude values ​​before and after the estimated point, and recording them as A1, A2, ..., A 2N .

[0051] The latitude and longitude estimation method of this embodiment is based on estimating point A x The latitude and longitude values ​​of the surrounding sampling points are fitted and estimated. Therefore, it is necessary to retrieve the sampling time at the estimated point A. x Multiple sampling points before and after the point with real longitude and latitude values ​​participate in subsequent calculations.

[0052] As a preferred embodiment, in order to improve the accuracy of the estimation result, it is best to select the sampling time closest to the estimation point A. x That is, according to the order of sampling time, select the estimated point A x The previous N sampling points with real latitude and longitude values, and the estimated point A x The next N sampling points have real longitude and latitude values, and these 2N sampling points can be recorded as A1, A2, ..., A 2N .

[0053] In some embodiments, N=3 or N=4 is preferably configured. That is, the estimated points A are extracted in time order. x The 3 or 4 sampling points before and after with real latitude and longitude values ​​are used to estimate point A. x The latitude and longitude values ​​are fitted and estimated.

[0054] S103, using 2N sampling points A1, A2, ..., A 2N The sampling time and longitude and latitude values ​​are used to generate a fitting curve.

[0055] In this embodiment, 2N sampling points A1, A2, ..., A 2N The sampling time and longitude and latitude values ​​are used to generate the longitude and latitude fitting curve using the least squares curve fitting algorithm to estimate point A. x The longitude and latitude values ​​are estimated.

[0056] S104: Estimated point A x Substitute the sampling time into the longitude and latitude fitting curve to calculate the estimated point A x The latitude and longitude values ​​of .

[0057] The latitude and longitude fitting curve of this embodiment can be presented in the form of a calculation formula with sampling time and latitude and longitude values ​​as variables. After obtaining the calculation formula of the latitude and longitude fitting curve, it is only necessary to calculate the estimated point A. x Substitute the sampling time into the latitude and longitude fitting curve calculation formula to calculate the estimated point A x The latitude and longitude values ​​of .

[0058] S105: Extract the sampling time at the estimated point A. x The M sampling points with real gamma values ​​before and after are denoted as B1, B2, ..., B 2M .

[0059] The gamma value estimation method of this embodiment is based on the estimation point A x The gamma value of the surrounding sampling points is fitted and estimated. Therefore, it is necessary to retrieve the sampling time at the estimated point A. xMultiple sampling points before and after the real gamma value participate in the subsequent calculation.

[0060] As a preferred embodiment, in order to improve the accuracy of the estimation result, it is best to select the sampling time closest to the estimation point A. x That is, according to the order of sampling time, select the estimated point A x The previous M sampling points with true gamma values, and the estimated point A x The next M sampling points have real gamma values, and these 2M sampling points can be recorded as B1, B2, ..., B 2M These 2M sampling points B1, B2, ..., B 2M It can be combined with the above 2N sampling points A1, A2, ..., A 2N It can overlap completely or partially.

[0061] In some embodiments, M=2 or M=3 is preferably configured. That is, the estimated points A are extracted in time order. x 2 or 3 sampling points with real gamma values ​​before and after are used to estimate point A x The gamma value is fitted and estimated. As a preferred embodiment, M is preferably less than or equal to N. That is, the number of sampling points used for gamma value fitting estimation is less than or equal to the number of sampling points used for latitude and longitude value fitting estimation. This parameter configuration method can shorten the program running time as much as possible and improve efficiency while ensuring the credibility of the latitude and longitude value and gamma value estimation results.

[0062] S106, according to 2M sampling points B1, B2, ..., B 2M With estimated point A x The distance is 2M sampling points B1, B2, ..., B 2M Assign weights.

[0063] Since the distribution of radionuclides in seawater is continuous, it is possible to estimate point A based on x The distance between the surrounding sampling points and the estimated point A x The degree of distance is 2M sampling points B1, B2, ..., B 2M Assign appropriate weights.

[0064] S107, according to B1, B2, ..., B of 2M sampling points 2M Gamma value and its weight, estimate the estimated point A x The gamma value of .

[0065] Considering the continuity of the distribution of radionuclides in seawater, it can be combined with the estimated point A x The gamma value of the surrounding sampling points is used to estimate the estimated point Ax The gamma value of the radioactive nuclides in seawater can be more consistent with the actual distribution of the radioactive nuclides in seawater.

[0066] Combine the following Figure 3 , the position estimation method of the ocean radioactive drifting buoy is elaborated in detail, which specifically includes the following processes:

[0067] S201, using 2N sampling points A1, A2, ..., A 2N The sampling time and longitude value are used to generate the longitude fitting curve.

[0068] In this embodiment, the selected 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and longitude values ​​into the following calculation formula to fit the longitude fitting curve:

[0069] jd=kt+b (1);

[0070] Among them, jd represents the longitude value, t represents the sampling time, and k and b are coefficients.

[0071] In order to facilitate calculation, a reference time can be determined first. The reference time should be earlier than 2N sampling points A1, A2, ..., A 2N The sampling time is then calculated for 2N sampling points A1, A2, ..., A 2N The difference between the sampling time and the reference time is used to replace the 2N sampling points A1, A2, ..., A 2N Substitute the sampling time into the fitting curve formula (1) for calculation.

[0072] Set 2N sampling points A1, A2, ..., A 2N The sampling time (difference) and longitude values ​​are substituted into formula (1) to obtain multiple sets of k and b values. The optimal solutions of k and b are calculated using the least squares method and substituted into formula (1) to generate the longitude fitting curve calculation formula.

[0073] S202, estimate point A x Substitute the sampling time into the longitude fitting curve to calculate the estimated point A x The longitude value of .

[0074] Estimated point A x Substitute the sampling time t into the above formula (1), and the calculated jd is the estimated point A x The longitude value of .

[0075] In this embodiment, the estimated point A can be calculated first x The difference between the sampling time and the reference time is taken as t and substituted into formula (1) to calculate the estimated point A.x The longitude value is jd.

[0076] S203, using 2N sampling points A1, A2, ..., A 2N The sampling time and latitude values ​​are used to generate the latitude fitting curve.

[0077] In this embodiment, the selected 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and latitude values ​​into the following calculation formula to fit the latitude fitting curve:

[0078] wd=k't+b' (2);

[0079] Among them, wd represents the latitude value, t represents the sampling time, and k' and b' are coefficients.

[0080] Similarly, t here is preferably substituted into 2N sampling points A1, A2, ..., A 2N The difference between the sampling time and the reference time is used to simplify the calculation process.

[0081] Set 2N sampling points A1, A2, ..., A 2N The sampling time (difference) and latitude values ​​are substituted into formula (2) to obtain multiple sets of k' and b' values. The optimal solutions of k' and b' are calculated using the least squares method and substituted into formula (2) to generate the latitude fitting curve calculation formula.

[0082] S204, estimate point A x Substitute the sampling time into the latitude fitting curve to calculate the estimated point A x The latitude value of .

[0083] Estimated point A x Substituting the sampling time t into the above formula (2), the calculated wd is the estimated point A x The latitude value of .

[0084] In this embodiment, the estimated point A can be calculated first x The difference between the sampling time and the reference time is taken as t and substituted into formula (2) to calculate the estimated point A. x The latitude value wd.

[0085] Thus, the estimation point A is completed. x position estimate.

[0086] Combine the following Figure 4 , the gamma value estimation method of seawater radionuclides is elaborated in detail, which specifically includes the following processes:

[0087] S301, calculate B1, B2, ..., B of 2M sampling points 2MEach sampling point in the estimated point A x The distance between.

[0088] In this embodiment, the estimated point A can be used x and sampling points B1, B2, ..., B 2M Calculate the distance between two points using their latitude and longitude values.

[0089] Specifically, if the longitude and latitude values ​​of two sampling points on the earth are known, the distance between the two sampling points can be calculated by substituting them into the following distance calculation formula:

[0090] d i =R*arccos[cos(Y1)*cos(Y2)*cos(X1-X2)+sin(Y1)*sin(Y2)]*π / 180 (3).

[0091] In formula (3), (X1, Y1) can be substituted into one of the sampling points B i The longitude and latitude values ​​of the estimated point A. x The longitude and latitude values; R is the radius of the earth, which can be taken as R = 6371km; π is taken as 3.1415926, and the distance d calculated from this i Sampling point B i With estimated point A x Here, the distance d i The units are the same as the units of the Earth's radius R.

[0092] The extracted 2M sampling points B1, B2, ..., B 2M Substituting the longitude and latitude values ​​into the above distance calculation formula (3), the distance between each sampling point B1, B2, ..., B 2M With estimated point A x The distances between them can be recorded as d1, d2, ..., d 2M .

[0093] S302, 2M sampling points B1, B2, ..., B 2M Assign weights.

[0094] In this embodiment, 2M sampling points B1, B2, ..., B 2M With estimated point A x The distance between each sampling point B1, B2, ..., B 2M Allocate weight values ​​reasonably.

[0095] Since the distribution of radionuclides in seawater is continuous, the distance estimation point A xThe closer the sampling point, the closer the gamma value is to the estimated point A. x In view of this, this embodiment uses 2M sampling points B1, B2, ..., B 2M With estimated point A x Based on the distance between, the distance estimation point A x The weight coefficient assigned to the distant sampling point is small, and the distance to the estimated point A x The weight coefficient assigned to the closest sampling points is large, that is, the 2M sampling points B1, B2, ..., B 2M The weight of the calculated 2M distances d1, d2, ..., d 2M There is a negative correlation between them, thus achieving a reasonable distribution of weight coefficients.

[0096] Specifically, 2M distances d1, d2, ..., d 2M The reciprocal sum of , that is:

[0097]

[0098] Then, each sampling point B1, B2, ..., B 2M With estimated point A x The reciprocal of the distance between divided by the reciprocal sum Sum, get the weight assigned to the sampling point. That is:

[0099]

[0100] Among them, W i is sampling point B i The assigned weights are i=1, 2, ..., 2M.

[0101] S303, according to 2M sampling points B1, B2, ..., B 2M The gamma value component is calculated based on the gamma value of and the weight assigned to it.

[0102] In this embodiment, 2M sampling points B1, B2, ..., B 2M The gamma value of each sampling point in is multiplied by its assigned weight to obtain the gamma value component corresponding to the sampling point. That is:

[0103] G i =W i ×g i ;

[0104] Among them, g i Sampling point B i The gamma value is the real value, that is, the gamma value actually collected by the ocean radioactive drifting buoy; G i Sampling point B iThe corresponding gamma value components. Thus, 2M gamma value components can be calculated.

[0105] S304, taking the sum of 2M gamma value components as the estimated point A x The gamma value of .

[0106] In this embodiment, the estimated point A can be obtained by adding 2M gamma value components. x The gamma value of . That is:

[0107]

[0108] Where G is the estimated point A x The gamma value of .

[0109] The process of estimating the gamma value of seawater radionuclides is completed.

[0110] For example:

[0111] Assume that a set of sampling data collected by an ocean radioactive drifting buoy is as follows:

[0112] A1: 2019-7-10 11:57 Longitude: 119.831535 Latitude: 35.615856 g1 = 0.044;

[0113] A2 / B1: 2019-7-10 12:0 Longitude: 119.831474 Latitude: 35.616001 g2=0.05;

[0114] A3 / B2: 2019-7-10 12:2 Longitude: 119.831383 Latitude: 35.616215 g3 = 0.063996;

[0115] A x :2019-7-10 12:4

[0116] A4 / B3: 2019-7-10 12:6 Longitude: 119.831245 Latitude: 35.616520g4=0.063996;

[0117] A5 / B4: 2019-7-10 12:9 Longitude: 119.831108 Latitude: 35.616776g5=0.066568;

[0118] A6: 2019-7-10 12:10 Longitude: 119.831062 Latitude: 35.616856g5=0.062456.

[0119] From the above sampling data, it can be seen that sampling point A xThe latitude and longitude values ​​and gamma values ​​of the sampling point A are lost. x As the estimation point, configure N = 3, M = 2, and start from the estimation point A in the order of sampling time. x Select three sampling points A1, A2, and A3 with real longitude and latitude values, and then select three sampling points A4, A5, and A6 with real longitude and latitude values ​​to estimate point A. x The latitude and longitude values ​​of the estimated point A are fitted. x Select two sampling points B1 and B2 with real gamma values ​​forward, and then select two sampling points B3 and B4 with real gamma values ​​backward to estimate point A. x The gamma value of is fitted to estimate .

[0120] Taking the time 2019-7-10 11:50 as the reference time, the difference between the sampling time and the reference time of the six sampling points A1, A2, A3, A4, A5, and A6 is calculated, and the longitude values ​​of the six sampling points A1, A2, A3, A4, A5, and A6 are extracted to form six groups of data, namely: (7,119.831535), (10,119.831474), (12,119.831383), (16,119.831245), (19,119.831108), (20,119.831062).

[0121] Substitute the above six sets of data into the longitude fitting curve formula: jd=kt+b, and calculate six sets of (k,b) coefficients. Use the least squares method to calculate the optimal solution of coefficients k and b, and generate the longitude fitting curve formula:

[0122] jd = 9.4 × 10 -5 ×t+119.83 (4).

[0123] Calculate the estimated point A x The difference between the sampling time 2019-7-10 12:4 and the reference time 2019-7-10 11:50 is 14. Substitute t=14 into the longitude fitting curve formula (4) to calculate the estimated point A. x Longitude value: jd = 9.4 × 10 -5 ×14+119.83=119.831316.

[0124] The latitude values ​​of the six sampling points A1, A2, A3, A4, A5, and A6 are extracted, and combined with the difference between the sampling time and the reference time of the six sampling points A1, A2, A3, A4, A5, and A6, six groups of data are formed, namely: (7, 35.615856), (10, 35.616001), (12, 35.616215), (16, 35.616520), (19, 35.616776), (20, 35.616856).

[0125] Substitute the above six sets of data into the latitude fitting curve formula: wd = k't + b', and calculate six sets of (k', b') coefficients. Use the least squares method to calculate the optimal solution of the coefficients k' and b', and generate the latitude fitting curve formula:

[0126] wd=9.77×10 -5 ×t+35.615 (5).

[0127] Calculate the estimated point A x The difference between the sampling time 2019-7-10 12:4 and the reference time 2019-7-10 11:50 is 14. Substituting t=14 into the latitude fitting curve formula (5), the estimated point A is calculated. x Latitude value: wd = 9.77 × 10 -5 ×14+35.615=35.6163678.

[0128] Thus, we get the estimated point A x The latitude and longitude values ​​are (119.831316, 35.6163678).

[0129] The latitude and longitude values ​​of the four sampling points B1, B2, B3, B4 and the estimated point A x Substitute the longitude and latitude values ​​of into the distance calculation formula (3) to calculate the distance from each sampling point to the estimated point. That is:

[0130] d1 = 6371*arccos[cos(35.616001)*cos(35.6163678)*cos(119.831474-119.831316)+sin(35.616001)*sin(35.6163678)*3.1415926 / 180 = 0.042881 km = 42.881 m;

[0131] d2 = 6371*arccos[cos(35.616215)*cos(35.616378)*cos(119.831383-119.831316)+sin(35.616215)*sin(35.616378)*3.1415926 / 180 = 0.017703 km = 17.703 m;

[0132] d3 = 6371*arccos[cos(35.616520)*cos(35.616378)*cos(119.831245-119.831316)+sin(35.616520)*sin(35.616378)*3.1415926 / 180 = 0.018434 km = 18.434 m;

[0133] d4=6371*arccos[cos(35.616776)*cos(35.616378)*cos(119.831108-119.831316)+sin(35.616776)*sin(35.616378)*3.1415926 / 180=0.049477 km=49.477 m.

[0134] Calculate the reciprocal sum of the four distances, namely:

[0135]

[0136] Calculate the weights assigned to the four sampling points B1, B2, B3, and B4, namely:

[0137]

[0138]

[0139]

[0140]

[0141] Calculate the gamma value components corresponding to the four sampling points B1, B2, B3, and B4. That is:

[0142] G1=W1×g1=15%×0.05=0.0075;

[0143] G 12 =W2×g2=37%×0.063996=0.02367852;

[0144] G3=W3×g3=35%×0.063996=0.0223986;

[0145] G4=W4×g4=13%×0.066568=0.00865384.

[0146] Calculate the estimated point A x The gamma value is:

[0147] G=G1+G2+G3+G4=0.0075+0.02367852+0.0223986+0.00865384=0.06223096.

[0148] The calculated gamma value G is used as the radionuclide gamma value of seawater at the longitude 119.831316 and latitude 35.616378 to complete the gamma value estimation process.

[0149] Thus, we obtain the estimated point A x The complete sampling data is:

[0150] A x :2019-7-10 12:4 Longitude: 119.831316 Latitude: 35.616378g=0.06223096.

[0151] Of course, the above is only 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 principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for estimating the position and gamma value of a marine radioactive drifting buoy, wherein the marine radioactive drifting buoy receives positioning data during drifting in seawater and detects seawater radionuclides at the position, generating sampling data including sampling time, longitude and latitude values ​​and gamma values ​​of seawater radionuclides of the sampling point; characterized in that: The estimation method includes: Find the sampling points where the latitude, longitude and gamma values ​​are missing in the sampled data as the estimated point A x ; Extract the sampling time at the estimated point A x The N sampling points before and after the time with real longitude and latitude values ​​are recorded as A1, A2, ..., A 2N , used to estimate point A x The longitude and latitude values ​​of are estimated; Extract the sampling time at the estimated point A x The M sampling points with real gamma values ​​before and after are denoted as B1, B2, ..., B 2M , used to estimate point A x The gamma value of is estimated; At the estimated point A x In the process of estimating the longitude and latitude values, 2N sampling points A1, A2, ..., A 2N The sampling time and longitude and latitude values ​​generate a fitting curve, and the estimated point A x Substitute the sampling time into the fitting curve and calculate the estimated point A x The latitude and longitude values ​​of At the estimated point A x In the process of estimating the gamma value, according to 2M sampling points B1, B2, ..., B 2M With estimated point A x The distance is 2M, weights are assigned to the 2M sampling points, and the estimated point A is estimated according to the gamma values ​​of the 2M sampling points and their weights. x The gamma value of .

2. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 1, characterized in that: The estimated point A x The process of estimating the longitude and latitude values ​​includes: The 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and longitude values ​​into the least squares curve fitting formula jd=kt+b, calculate the values ​​of coefficients k and b, and generate the longitude fitting curve; Estimated point A x Substitute the sampling time into the longitude fitting curve to calculate the estimated point A x The longitude value of The 2N sampling points A1, A2, ..., A 2N Substitute the sampling time and latitude values ​​into the least squares curve fitting formula wd=k't+b', calculate the values ​​of coefficients k' and b', and generate the latitude fitting curve; Estimated point A x Substitute the sampling time into the latitude fitting curve to calculate the estimated point A x The latitude value of Among them, jd represents the longitude value, wd represents the latitude value, and t represents the sampling time.

3. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 2, characterized in that: When substituting the sampling times of the 2N sampling points and the estimation points into the fitting curve formula, firstly determining a reference time, the reference time being earlier than the sampling times of the 2N sampling points; Then, the difference between the sampling time of the 2N sampling points and the estimation point and the reference time is calculated, and the difference is used to replace the sampling time and substituted into the fitting curve formula for calculation.

4. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 1, characterized in that: The 2N sampling points A1, A2, ..., A 2N It is the sampling time distance from the estimated point A among the sampling points with real latitude and longitude values. x The sampling time of the 2N most recent sampling points.

5. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 1, characterized in that: The 2M sampling points B1, B2, ..., B 2M Among the sampling points with true gamma values, the sampling time is far from the estimated point A x The sampling time of the 2M sampling points most recent.

6. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 1, characterized in that: The value of M is 2 or 3; the value of N is greater than or equal to M.

7. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to any one of claims 1 to 6, characterized in that: The estimated point A x The process of estimating the gamma value includes: Using the estimated point A x and the 2M sampling points B1, B2, ..., B 2M The latitude and longitude values ​​of each sampling point B1, B2, ..., B 2M With estimated point A x The distances between them are denoted as d1, d2, ..., d 2M ; According to 2M distances d1, d2, ..., d 2M The 2M sampling points B1, B2, ..., B 2M Assign weights; Calculate the 2M sampling points B1, B2, ..., B 2M The sum of the gamma value and its weight is used as the estimated point A x The gamma value of .

8. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 7, characterized in that: In calculating each of the sampling points B1, B2, ..., B 2M With estimated point A x When the distance between each sampling point B1, B2, ..., B 2M The latitude and longitude values ​​of the estimated point A x Substitute the longitude and latitude values ​​into the following distance calculation formula to obtain: d i =R*arccos[cos(Y1)*cos(Y2)*cos(X1-X2)+sin(Y1)*sin(Y2)]*π / 180; Among them, d i Indicates sampling point B i With estimated point A x The distance between them; R is the radius of the earth; (X1, Y1) is the sampling point B i The longitude and latitude values ​​of the estimated point A. x The longitude and latitude values ​​of .

9. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 7, characterized in that: For the 2M sampling points B1, B2, ..., B 2M When allocating weights, the 2M sampling points B1, B2, ..., B 2M The weight of the 2M distances d1, d2, ..., d 2M Negatively correlated.

10. The method for estimating the position and gamma value of a marine radioactive drifting buoy according to claim 9, characterized in that: The 2M sampling points B1, B2, ..., B 2M The weight distribution process includes: Calculate the reciprocal sum of 2M distances: Calculate sampling point B i Weight:

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