A ship end PNT information integrity level evaluation method based on grey correlation degree

Abstract

The application provides a ship end PNT information integrity grade evaluation method based on a grey correlation degree, comprising: constructing a ship end PNT information integrity evaluation matrix; calculating a comprehensive weight vector of ship end PNT information integrity grade influence factor indexes, wherein the comprehensive weight vector is determined according to subjective weight vectors and objective weight vectors of the ship end PNT information integrity grade influence factor indexes; calculating a grey correlation coefficient of each ship end PNT information integrity grade influence factor index based on the ship end PNT information integrity evaluation matrix, calculating a grey correlation degree based on the grey correlation coefficient and the comprehensive weight vector, and obtaining a final integrity grade evaluation result according to a ranking result of the grey correlation degree. The application evaluates the ship end PNT information integrity grade through the grey correlation degree method, so that the evaluation result is more scientific and reasonable, the efficiency of the crew operation is improved, and the risk caused by the crew's judgment on the ship end PNT information depending on human experience is greatly reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of ship positioning and navigation, and particularly relates to a ship end PNT information integrity level evaluation method based on grey correlation degree. BACKGROUND

[0002] In order to ensure the safety of marine navigation, the International Maritime Organization (IMO) adopts elastic positioning, navigation and timing (PNT) as the positioning and navigation solution for the future maritime field, especially for unmanned ships. With the increase of ship traffic density, the increase of various intentional or unintentional electromagnetic frequency interference, and the increase of PNT data sources collected by ship navigation sensors in real time, it is more and more difficult to rely on human experience to judge the PNT information output by the ship end, which cannot meet the safety requirements of ship navigation. The automatic comprehensive evaluation of the PNT information integrity of the ship end can provide accurate scientific basis for the operation of the crew, and has important significance for ensuring the safety of ship navigation.

[0003] At present, the integrity evaluation is mainly focused on reflecting the integrity performance from the parameters such as alarm time, alarm threshold and integrity risk, and the information is too scattered, so that the crew cannot directly supervise the PNT information integrity performance of the ship end. Although the PNT data processing guide released by the Navigation, Communications and Search and Rescue (NCSR) of the IMO has given four levels of None (N), Low (L), Medium (M) and High (H) for integrity evaluation, but it does not give the specific evaluation method. In view of this, it is a technical problem to be solved in the field to establish a ship end PNT information integrity level evaluation method to provide the crew with a direct comprehensive evaluation result of the PNT information integrity of the ship end, and to improve the operation efficiency of the crew. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a ship end PNT information integrity level evaluation method based on grey correlation degree, which comprehensively evaluates the PNT information integrity of the ship end to meet the navigation requirements, improves the operation efficiency of the crew, and greatly reduces the risk caused by the crew relying on human experience to judge the PNT information of the ship end.

[0005] The technical means adopted by the present application are as follows:

[0006] The present application discloses a ship end PNT information integrity level evaluation method based on grey correlation degree, comprising:

[0007] S1. Construct the ship-side PNT information integrity assessment matrix X = (x ij ) m×n , where m represents the number of integrity levels, n represents the number of influencing factors of ship-side PNT information integrity level, and x ij Represents the original data of influencing factor index j at integrity level i, i = 1, ..., m, j = 1, ..., n;

[0008] S2. Calculate a comprehensive weight vector for the ship-side PNT information integrity level influencing factor indicators, where the comprehensive weight vector is determined based on the subjective weight vector and the objective weight vector of each ship-side PNT information integrity level influencing factor indicator;

[0009] S3, based on the ship-side PNT information integrity assessment matrix X = (x ij ) m×n The grey correlation coefficient of the influencing factor index of the PNT information integrity level of each ship side is calculated, the grey correlation degree is calculated based on the grey correlation coefficient and the comprehensive weight vector, and the final integrity level assessment result is obtained according to the sorting result of the grey correlation degree.

[0010] Furthermore, S1 also includes a step of standardizing the constructed ship-side PNT information integrity assessment matrix.

[0011] Furthermore, S2 calculates the comprehensive weight vector of the influencing factors of the ship-side PNT information integrity level, including:

[0012] S231, calculate the distance index d according to the following formula j :

[0013]

[0014] Among them, α j is the risk preference coefficient, 0≤α j ≤1, is the objective weight vector, is the subjective weight vector,

[0015] Distance index d j α is the minimum value j Calculate according to the following formula:

[0016]

[0017] S232, based on the obtained α j The comprehensive weight vector of the influencing factors of the PNT information integrity level of each ship end is obtained according to the following formula:

[0018]

[0019] Further, the subjective weight vector of each ship end PNT information integrity level influencing factor index in S2 is obtained according to the following method:

[0020] S211, the relative relationship between each pair of ship end PNT information integrity level influencing factor indexes is measured by using a 1-9 scale, and a judgment matrix A=(a kj ) n×n :

[0021]

[0022] In the formula, a kj is a scale, reflecting the relative importance of the kth influencing factor index of the ship end PNT information integrity level and the jth influencing factor index, a jk =(a kj ) -1 ,

[0023] S212, the consistency of the judgment matrix A is checked:

[0024]

[0025] Where λ max represents the maximum eigenvalue of the judgment matrix A, n represents the order of A, CI is an evaluation factor for measuring the deviation of the judgment matrix A from consistency,

[0026] If CI=0, the judgment matrix A passes the consistency check, otherwise the ratio of CI and the average random consistency index RI, CR, needs to be calculated, and the following formula is judged:

[0027]

[0028] If the above formula is true, the judgment matrix A passes the consistency check, otherwise return to S211 to repeat the above process until the established judgment matrix A passes the consistency check;

[0029] S213, the subjective weight vector of each ship end PNT information integrity level influencing factor index is calculated according to the following formula

[0030]

[0031] Where, the vector b kj is the column normalized result of the scale a kj in the judgment matrix A.

[0032] Further, the objective weight vector of each ship end PNT information integrity level influencing factor index in S2 is obtained according to the following method:

[0033] S221, calculate the entropy value H of each ship end PNT information integrity level influencing factor index according to the following formula j :

[0034]

[0035] wherein f ij is the proportion of integrity level i in the jth ship end PNT information integrity level influencing factor index, which is calculated according to the following formula:

[0036]

[0037] S222, calculate the objective weight vector of each ship end PNT information integrity level influencing factor index according to the following formula

[0038]

[0039] Further, in S3, the ship end PNT information integrity evaluation matrix X=(x ij ) m×n The grey correlation coefficient of each ship end PNT information integrity level influencing factor index is calculated, including:

[0040] S311, obtain the subsequence X i =[x i (1), x i (2), …, x i (n)] of each ship end PNT information integrity level influencing factor index, wherein i=1, 2, …, m;

[0041] S312, obtain the reference sequence X0=[x0(1), x0(2), …, x0(n)] composed of the maximum value in the subsequence of each ship end PNT information integrity level influencing factor index;

[0042] S313, calculate the grey correlation coefficient of each ship end PNT information integrity level influencing factor index according to the following formula:

[0043]

[0044] wherein p is the resolution coefficient, taking a value between 0 and 1, and ξ i (j) is the correlation coefficient of the subsequence and the reference sequence of each ship end PNT information integrity level influencing factor index, is the minimum absolute difference between the ship end PNT information integrity level influencing factor index of the subsequence and the reference sequence index, is the maximum absolute difference between the ship end PNT information integrity level influencing factor index of the subsequence and the reference sequence index.

[0045] Further, the grey correlation degree is calculated based on the grey correlation coefficient and the comprehensive weight vector in S3, including: the grey correlation degree is calculated according to the following formula:

[0046]

[0047] Wherein, r i is the grey correlation degree of the i th integrity level.

[0048] Further, the final integrity level evaluation result is obtained according to the ranking result of the grey correlation degree in S3, including: the correlation sequence of the integrity level of the evaluation object is established according to the ranking result of the grey correlation degree of the PNT information integrity level of each ship end, and the maximum correlation degree is selected as the final integrity level evaluation result.

[0049] Compared with the prior art, the present application has the following advantages:

[0050] The ship end PNT information integrity level evaluation method of the present application evaluates the ship end PNT information integrity level by the grey correlation degree method, so that the evaluation result is more scientific and reasonable, the efficiency of the crew operation is improved, and the risk caused by the crew's judgment of the ship end PNT information depending on human experience is greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0052] Figure 1 The figure is the overall flow chart of the ship end PNT information integrity level evaluation method of the present application.

[0053] Figure 2 The figure is the specific execution flow chart of the ship end PNT information integrity level evaluation method in the embodiment. DETAILED DESCRIPTION

[0054] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0055] As Figure 1As shown, it is a ship end PNT information integrity level evaluation method based on grey correlation degree, which is provided by the embodiment of the application, and the specific steps of the method are as follows:

[0056] S1, constructing a ship end PNT information integrity evaluation matrix X=(x ij ) m×n , wherein m represents the number of integrity levels, and n represents the number of ship end PNT information integrity level influencing factor indexes; the original data of each ship end PNT information integrity level influencing factor index under different integrity levels is determined, and the steps are as follows:

[0057] S111, four integrity levels are preferably determined in this embodiment, which are N, L, M and H.

[0058] S112, considering the ship end PNT information integrity level influencing factors such as accuracy, alarm time, alarm threshold, integrity risk, navigation stage and navigation source, four ship end PNT information integrity level influencing factor indexes are preferably determined in this embodiment. Among them, the interval of the original data distribution of each ship end PNT information integrity level influencing factor index is dynamically adjusted by the navigation stage, and the navigation source is used to update the accuracy.

[0059] According to the minimum performance requirements of radio navigation in each navigation stage in IMO A.915(22) and A.1046(27) resolutions, the interval of the original data distribution of each ship end PNT information integrity level influencing factor index is shown in Table 1.

[0060] Table 1 Interval of each ship end PNT information integrity level influencing factor index

[0061]

[0062]

[0063] S113, according to the navigation data obtained in real time during ship navigation, the ship end PNT information integrity evaluation matrix X is constructed according to the distribution interval of each ship end PNT information integrity level influencing factor index in Table 1. ij (i=1,…,m,j=1,…,n) represents the original data of the ship end PNT information integrity level influencing factor index j under the integrity level i. After standardization, the evaluation matrix X is:

[0064]

[0065] S2, the comprehensive weight vector of the ship end PNT information integrity level influencing factor index is calculated, and the comprehensive weight vector is determined according to the subjective weight vector and the objective weight vector of each ship end PNT information integrity level influencing factor index;

[0066] The subjective weight vector of each ship end PNT information integrity level influencing factor index is obtained according to the following method:

[0067] S211, the relative relationship between each pair of ship end PNT information integrity level influencing factor indexes is measured by using the 1-9 scale shown in Table 2, and a judgment matrix A=(a kj ) n×n is established.

[0068]

[0069] In the formula, a kj is a scale, reflecting the relative importance of the kth influencing factor index of the ship end PNT information integrity level and the jth influencing factor index, a jk =(a kj ) -1 , and its specific meaning is shown in the following Table 2:

[0070] Table 2 Scale Table

[0071] Scale of Proportion Definition 1 i factor is equally important to j factor 3 i factor is slightly more important than j factor 5 i factor is moderately more important than j factor 7 i factor is strongly more important than j factor 9 i factor is absolutely more important than j factor 2,4,6,8 the comparison between i and j is intermediate values of the adjacent judgments

[0072] S212, the consistency of the judgment matrix A is checked:

[0073]

[0074] In this embodiment, λ max =4.264, n=4, CI=0.088001, which does not directly pass the consistency check. Further calculation of the ratio of CI and the average random consistency index RI, RI can be obtained by referring to Table 3. CR<0.1, the judgment matrix A passes the consistency check. Wherein:

[0075]

[0076] Table 3 Average Random Consistency Index

[0077] n 1 2 3 4 5 6 7 8 9 RI 0 0 0.58 0.9 1.12 1.24 1.32 1.41 1.45

[0078] S213, the subjective weight vector of each ship end PNT information integrity level influencing factor index is calculated in this embodiment according to the following formula w S =(0.4724, 0.1991, 0.0877, 0.2408):

[0079]

[0080] Wherein, the vector b kj is the scale a kjThe column normalization result is:

[0081]

[0082] The objective weight vector of each ship end PNT information integrity level influencing factor index is obtained according to the following method:

[0083] S221, the entropy value H of each ship end PNT information integrity level influencing factor index is calculated according to the following formula: j :

[0084]

[0085] Wherein, f ij is the proportion of integrity level i in the jth ship end PNT information integrity level influencing factor index, which is calculated according to the following formula:

[0086]

[0087] S222, the objective weight vector of each ship end PNT information integrity level influencing factor index calculated in this embodiment is w O =(0.2433, 0.3575, 0.2988, 0.1005):

[0088]

[0089] The comprehensive weight vector calculation of the ship end PNT information integrity level influencing factor index includes:

[0090] S231, the distance index d j is calculated according to the following formula:

[0091]

[0092] Wherein, α j is the risk preference coefficient, 0≤α j ≤1, is the objective weight vector, is the subjective weight vector.

[0093] When the distance index d j is the minimum value, α j is calculated according to the following formula:

[0094]

[0095] S232, based on the obtained α j The comprehensive weight vector of each ship end PNT information integrity level influencing factor index calculated in this embodiment is w C= (0.3813, 0.3067, 0.1484, 0.1635) :

[0096]

[0097] S3, based on the ship end PNT information integrity evaluation matrix X = (x ij ) m×n The grey correlation coefficient of each ship end PNT information integrity level influencing factor index is calculated, including:

[0098] S311, obtaining the subsequence X i = [x i (1), x i (2),..., x i (n)], wherein i = 1, 2,..., m;

[0099] S312, obtaining the reference sequence X0 = [1, 1, 1, 1] composed of the maximum value in the subsequence of each ship end PNT information integrity level influencing factor index in the embodiment;

[0100] S313, calculating the grey correlation coefficient of each ship end PNT information integrity level influencing factor index according to the following formula:

[0101]

[0102] In the formula, the resolution coefficient ρ = 0.5; ξ i (j) is the correlation coefficient of the subsequence of each ship end PNT information integrity level influencing factor index and the reference sequence.

[0103] S321, based on the grey correlation coefficient and the comprehensive weight vector, the grey correlation degree calculated in the embodiment is r i = (0.6772, 0.7484, 0.7034, 0.4972) :

[0104]

[0105] S331, according to the ranking result of the grey correlation degree of each ship end PNT information integrity level, the correlation sequence of the integrity level of the evaluation object is established as: (M, L, H, N). Therefore, it is known that the result of the ship end PNT information integrity level evaluation is M. The method realizes the automatic comprehensive evaluation of the PNT information integrity of the ship end, greatly improves the efficiency of the operation of the crew, and has important significance for ensuring the safety of ship navigation.

[0106] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for evaluating the integrity level of ship-side PNT information based on grey correlation, characterized in that: include: S1. Construct the ship-side PNT information integrity assessment matrix according to the distribution range of the influencing factor indicators of each ship-side PNT information integrity level ,in, Indicates the number of integrity levels, including N, L, M, and H. Indicates the number of indicators affecting the integrity level of ship-side PNT information. Integrity level Influencing factor indicators The original data, , The factors affecting the integrity level of ship-side PNT information include accuracy, alarm time, alarm threshold, integrity risk, navigation phase, and navigation source. The distribution range of the raw data of each ship-side PNT information integrity level influencing factor indicator is dynamically adjusted according to the navigation phase, and the navigation source is used to update the accuracy. S2. Calculate a comprehensive weight vector for the ship-side PNT information integrity level influencing factor indicators, where the comprehensive weight vector is determined based on the subjective weight vector and the objective weight vector of each ship-side PNT information integrity level influencing factor indicator; S3. Ship-side PNT information integrity assessment matrix The grey correlation coefficient of the influencing factor index of the PNT information integrity level of each ship side is calculated, the grey correlation degree is calculated based on the grey correlation coefficient and the comprehensive weight vector, and the final integrity level assessment result is obtained according to the sorting result of the grey correlation degree.

2. The method for evaluating ship-side PNT information integrity based on grey relational degree according to claim 1, characterized in that: S1 also includes a step of standardizing the constructed ship-side PNT information integrity assessment matrix.

3. According to the method for evaluating the integrity level of ship-side PNT information based on grey correlation, the step S2 of calculating the comprehensive weight vector of the influencing factors of the integrity level of ship-side PNT information comprises: S231. Calculate the distance index according to the following formula : in, is the risk preference coefficient, , is the objective weight vector, is the subjective weight vector, Distance indicator When the minimum Calculate according to the following formula: ； S232, based on the obtained The comprehensive weight vector of the influencing factors of the PNT information integrity level of each ship end is obtained according to the following formula: : 。 4. According to the method for evaluating ship-side PNT information integrity level based on grey relational degree in claim 1, the subjective weight vector of each ship-side PNT information integrity level influencing factor index in S2 is obtained according to the following method: S211. Use a 1-9 scale to measure the relative relationship between the influencing factors of the PNT information integrity level of each ship, and establish a judgment matrix : In the formula It is a scale that reflects the integrity level of the ship-side PNT information. The influencing factor index and The relative importance of the influencing factor indicators, , S212, the judgment matrix Perform consistency check: in Represents the judgment matrix The maximum eigenvalue of express The order of To measure the judgment matrix The evaluation factor of deviation from consistency, like , judgment matrix Pass the consistency check directly, otherwise further calculation is required and the average random consistency index Ratio , and determine whether the following formula is true: If the above formula is established, then the judgment matrix If the consistency check is passed, return to S211 and repeat the above process until the judgment matrix is ​​established. Pass the consistency test; S213. Calculate the subjective weight vector of the influencing factors of the PNT information integrity level of each ship according to the following formula: : in, vector is the judgment matrix The scale in Normalize the results by columns.

5. According to the method for evaluating the integrity level of ship-side PNT information based on grey correlation, the objective weight vector of each ship-side PNT information integrity level influencing factor index in S2 is obtained according to the following method: S221. Calculate the entropy value of the influencing factor index of the PNT information integrity level of each ship according to the following formula: : in, Is the integrity level In the The weight of the influencing factors of the ship-side PNT information integrity level is calculated according to the following formula: ； S222. Calculate the objective weight vector of the influencing factors of the PNT information integrity level of each ship according to the following formula: : 。 6. According to the method for evaluating the integrity level of ship-side PNT information based on grey correlation degree in claim 1, the ship-side PNT information integrity evaluation matrix in S3 is used. Calculate the grey correlation coefficient of the influencing factors of the PNT information integrity level of each ship, including: S311. Obtain the subsequence of the influencing factor indicators of the PNT information integrity level of each ship side ,in ; S312: Obtain a reference sequence consisting of the maximum values ​​of the subsequences of the influencing factors of the PNT information integrity level at each ship end. ; S313. Calculate the grey correlation coefficient of the influencing factor index of the PNT information integrity level at each ship end according to the following formula: in, is the resolution coefficient, which ranges from 0 to 1. is the correlation coefficient between the index subsequence of the factors affecting the integrity level of PNT information at each ship end and the reference sequence, is the minimum absolute difference between the subsequence's ship-side PNT information integrity level influencing factor index and the reference sequence index, It is the maximum absolute difference between the influencing factor index of the subsequence's ship-side PNT information integrity level and the reference sequence index.

7. The method for evaluating ship-side PNT information integrity level based on grey correlation according to claim 1, wherein the step S3 calculates the grey correlation based on the grey correlation coefficient and the comprehensive weight vector, comprising: The grey relational degree is calculated according to the following formula: in, For the The grey relational degree of each integrity level.

8. The method for evaluating ship-side PNT information integrity based on grey correlation according to claim 1, wherein S3 obtains a final integrity evaluation result based on the sorting result of the grey correlation, comprising: According to the sorting results of the grey correlation degree of the integrity level of each ship's PNT information, a correlation sequence of the integrity level of the assessment object is established, and the maximum correlation degree is selected as the final integrity level assessment result.

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