Power transmission and transformation project water and soil loss area feature analysis method and system

Abstract

The invention discloses a power transmission and transformation project water and soil loss area feature analysis method, and relates to the technical field of power transmission and transformation project water and soil conservation measure governance analysis, and the method comprises the steps: obtaining the line laying information of a power transmission and transformation project, determining a plurality of water and soil erosion points based on the line laying information, and carrying out the type division; every two subsets in each erosion unit group are subjected to similarity comparison, and the two subsets with the water and soil erosion degree similarity value meeting a preset value are combined into a preferred subset pair; identifying associated erosion points of the preferred subset on the line laying information according to the first position information, judging the similarity of each associated erosion point and the water and soil erosion degree of the preferred subset, and merging the point locations meeting the requirements into a preferred set; and defining common areas in the line laying information based on the point locations involved in the preferred set, and integrating the common areas of the same kind to obtain at least one prevention and control area. According to the analysis method and system, the water and soil erosion similarity judgment is carried out on point positions of all dry lines by utilizing the characteristic that water and soil erosion point positions of a power transmission and transformation project are distributed in a point and line mode, a plurality of common areas are obtained in combination with a two-point positioning method, and finally prevention and control areas with the same kind of water and soil erosion characteristics are formed. And the rationality of subsequent regional water and soil treatment is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of soil and water conservation measures management and analysis for power transmission and transformation projects, and in particular to a method and system for analyzing regional characteristics of soil and water loss in power transmission and transformation projects. Background Art

[0002] The impact of power transmission and transformation project construction on soil erosion is closely related to the natural environment such as landform, precipitation, soil, vegetation, etc., and the influence of landform conditions on soil erosion of power transmission and transformation construction projects is particularly prominent. The steeper the mountain, the more serious the soil erosion caused by the construction of power transmission and transformation projects. However, due to the special location of the soil erosion parts of power transmission and transformation projects, it is difficult to control soil erosion, making the soil and water conservation problem of power transmission and transformation projects more and more prominent. Since the regionalized prevention and control system of soil erosion of power transmission and transformation projects in cross-hill areas is not yet mature, it is difficult to take appropriate and reasonable prevention and control measures for all regions. In addition, the soil erosion caused by power transmission and transformation projects generally presents the characteristics of "points and lines", which makes it more difficult to carry out zoning control. Especially in terms of taking prevention and control measures, there is a lack of planning strategies for the implementation of prevention and control measures, and it is impossible to carry out reasonable regionalized soil and water control operations according to the transmission line project.

[0003] At present, when regionalizing soil and water conservation according to power transmission line projects, they are divided into different areas according to the scope of each jurisdiction's geographical area. On the one hand, when dividing the areas, they only rely on geographical location, which may lead to the problem that the difference of soil and water erosion in different areas is too small or too large, and the common characteristics of soil and water erosion are not taken into consideration. On the other hand, the soil and water erosion of power transmission and transformation projects generally presents the characteristics of a combination of "points and lines". Some scattered points have not been reasonably planned according to the characteristics of soil and water erosion, resulting in unreasonable soil and water conservation measures. Summary of the invention

[0004] The purpose of the present invention is to provide a method and system for analyzing the regional characteristics of soil erosion in power transmission and transformation projects. The method and system utilize the "point and line" distribution characteristics of soil erosion points in power transmission and transformation projects to make similarity judgments on the soil erosion properties of all trunk line points, and combine the two-point positioning method to obtain multiple common areas, and finally form prevention and control areas with similar soil erosion characteristics, thereby improving the rationality of subsequent regional soil and water management.

[0005] The embodiment of the present invention is achieved as follows:

[0006] In a first aspect, a method for analyzing regional characteristics of soil erosion in a power transmission and transformation project comprises the following steps: obtaining line laying information of the power transmission and transformation project, determining a number of soil erosion points based on the line laying information, classifying the several soil erosion points into types, and obtaining a plurality of similar erosion unit groups; performing a pairwise similarity comparison on the soil erosion degree of each subset in each erosion unit group, and merging two subsets whose soil erosion degree similarity values ​​meet a preset value into a preferred subset pair; locating first position information of the preferred subset pair in the line laying information, identifying the associated erosion point of the preferred subset pair in the line laying information according to the first position information, and determining each The similarity between the associated erosion points and the preferred subset in terms of soil erosion degree is used to merge the associated erosion points and the preferred subset pairs that meet the similarity threshold into a preferred set; based on the points involved in the preferred set, common areas are delineated in the line laying information, and the similar common areas are integrated to obtain at least one prevention and control area; wherein, the line laying information includes a trunk line and at least one branch line, and when identifying the associated erosion points of the preferred subset pair in the line laying information, if two subsets of a preferred subset pair appear on two different branch lines respectively, all points passed on the shortest path of the trunk line are determined as associated erosion points.

[0007] In an optional implementation manner, the determining of the similarity between the soil and water erosion degree of each associated erosion point and the preferred subset pair, and merging the associated erosion points exceeding the similarity threshold value with the preferred subset pair into a preferred set specifically comprises the following steps: determining the similarity of soil and water erosion degree of each associated erosion point with the two subsets of the preferred subset pair one by one, and if the comparison result with either of the two subsets of the preferred subset pair exceeds the similarity threshold value, merging the associated erosion point into the preferred set.

[0008] In an optional implementation manner, the similarity judgment of the water and soil erosion degree of each associated erosion point with the two subsets of the preferred subset pair is performed one by one using the following calculation model:

[0009] The similarity between the associated erosion point P and the subset A of the preferred subset pair is judged:

[0010]

[0011] The similarity between the associated erosion point P and the subset B of the preferred subset pair is judged:

[0012]

[0013] In formula (1) and formula (2), p=(p 1 , p 2 , ..., p n) is the eigenvector of the associated erosion point P; a=(a 1 , a 2 , ..., a n ) is the eigenvector of subset A; b=(b 1 , b 2 , ..., b n ) is the eigenvector of subset B.

[0014] In an optional embodiment, the eigenvector p, the eigenvector a and the eigenvector b are all numerical groups obtained by normalizing or standardizing soil and water erosion characteristics, wherein the soil and water erosion characteristics include at least one of soil type, slope, vegetation coverage, rainfall or runoff rate.

[0015] In an optional implementation, the method further includes the following steps after determining the similarity between each of the associated erosion points and the preferred subset for the water and soil erosion degree, and merging the associated erosion points exceeding the similarity threshold value with the preferred subset into a preferred set: constructing all the associated erosion points into a pre-subset group, marking the associated erosion points below the similarity threshold value as low-associated erosion points, determining the number of the low-associated erosion points, and calculating the ratio of the number of low-associated erosion points to the total number of the pre-subset group; if the ratio is less than a preset ratio, all the low-associated erosion points are incorporated into the preferred set.

[0016] In an optional embodiment, the step of determining the number of the low-correlation erosion points and calculating the ratio of the number of the low-correlation erosion points to the total number of the pre-subset group further includes the following steps: obtaining the second position information of each of the low-correlation erosion points in the line laying information, determining the interval distance between each two second position information, calculating the number of interval distances greater than a preset distance, and if the number is greater than a preset ratio, executing the step of incorporating all the low-correlation erosion points into the preferred set; otherwise, executing the step of not incorporating all the low-correlation erosion points into the preferred set.

[0017] In an optional implementation manner, the common areas are delineated in the line laying information based on the points involved in the preferred set, and the common areas of the same type are integrated, specifically including the following steps: obtaining the third position information of each point involved in the preferred set, and concatenating all the third position information to form the common area of ​​the preferred set; determining the water and soil erosion degree of each point involved in the preferred set, and calculating typical parameters of water and soil erosion based on all water and soil erosion degree data as representative values ​​of the corresponding common areas; identifying all common areas with representative values ​​in the same interval, and constructing them into a group of common areas with the same attributes; identifying the overlapping parameters of the common areas in each group of common areas with the same attributes, and judging whether the overlapping parameters are greater than the preset parameters, and if the overlapping parameters are greater than the preset parameters, merging the common areas involved in the overlap into the prevention and control area, wherein the overlapping parameters include the overlapping positions and their overlapping areas.

[0018] In an optional implementation, the determination of whether the overlap parameter is greater than a preset parameter and, if so, merging the common areas involved in the overlap into the prevention and control area further includes the following steps: if the overlap parameter is less than the preset parameter, calculating the difference between the overlap parameter and the preset parameter, and selecting a processing method for the common areas according to the difference; when the difference is less than the preset parameter, identifying the overlapping areas of the common areas involved in the overlap, and if the overlapping areas are greater than the preset area, merging the common areas involved in the overlap into the prevention and control area; when the difference is equal to the preset parameter, entering the step of determining whether each common area in the group of common areas with the same attributes forms a prevention and control area separately.

[0019] In an optional implementation, when the difference value is equal to a preset parameter, the interval distance between each two groups of common areas in the same attribute common area group is determined, and the representative value difference of the two groups of common areas whose interval distance is less than the preset interval value is judged. If the representative value difference is less than the preset difference, the common areas that meet the preset interval value and representative value difference requirements are merged into a prevention and control area.

[0020] In the second aspect, a system for analyzing regional characteristics of soil erosion in power transmission and transformation projects includes:

[0021] A first acquisition unit is used to acquire line laying information of a power transmission and transformation project, determine a plurality of water and soil erosion points based on the line laying information, classify the plurality of water and soil erosion points into types, and obtain a plurality of similar erosion unit groups, wherein the line laying information includes a trunk road and at least one branch road;

[0022] A first calculation unit is used to perform a pairwise similarity comparison on the water and soil erosion degree of each subset in each erosion unit group, and merge two subsets whose water and soil erosion degree similarity values ​​meet a preset value into a preferred subset pair;

[0023] A first processing unit is used to locate the first position information of the preferred subset pair in the route laying information, identify the associated erosion points of the preferred subset pair in the route laying information according to the first position information, determine the similarity between each associated erosion point and the water and soil erosion degree of the preferred subset pair, and merge the associated erosion points and the preferred subset pair that meet the similarity threshold value into a preferred set; wherein, when identifying the associated erosion points of the preferred subset pair in the route laying information, if two subsets of a preferred subset pair appear on two different branch roads respectively, all points passed on the shortest path of the main route are determined as associated erosion points;

[0024] The second processing unit demarcates common areas in the line laying information based on the points involved in the preferred set, and integrates the same type of common areas to obtain at least one prevention and control area.

[0025] The beneficial effects of the embodiments of the present invention are:

[0026] The method and system for analyzing regional characteristics of soil erosion in power transmission and transformation projects provided by the embodiment of the present invention are aimed at the soil erosion points involved in the laying lines (main lines and branch lines) of the entire power transmission and transformation project, and the similarity is judged between two soil erosion points with the same soil erosion type. The method of directly obtaining the remaining associated erosion points by two highly similar soil erosion points, that is, the method of locating the remaining associated points by two points, can efficiently obtain all similar soil erosion points, and will not miss points such as scattered branch lines. On this basis, the points selected by the similarity standard constitute a preferred set, and this preferred set can mark the same type and nature of head erosion points to facilitate area division. Finally, in the multiple divided areas, they can be sorted and merged according to the overlapping situation to obtain the prevention and control area with the same attribute. The prevention and control area has typical soil erosion regionalization characteristics, so that appropriate and reasonable prevention and control treatment operations can be carried out in a targeted manner.

[0027] In general, the method and system for analyzing the characteristics of soil erosion areas in power transmission and transformation projects provided in the embodiments of the present invention use the similarity of the degree of soil erosion at points to define the scope and make analysis and judgments. It not only takes into account the point and line characteristics of the geographically laid lines, but also combines and divides them according to the similarity of soil erosion properties, so that the final soil erosion area has typical erosion characteristics to facilitate targeted soil and water prevention and control. At the same time, all the head erosion points involved are involved in the process analysis, and all distribution forms are covered by the line laying information, so that there will be no omission of scattered distributions (especially head erosion points of branch lines) without soil erosion characteristic analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 A flowchart of the main steps of the analysis method provided by an embodiment of the present invention;

[0030] Figure 2 for Figure 1 A flow chart of one of the main steps S300;

[0031] Figure 3 for Figure 1 A flowchart of one of the main steps S400 is shown;

[0032] Figure 4 An exemplary module diagram of an analysis system provided by an embodiment of the present invention.

[0033] Icons: 500 - analysis system; 510 - first acquisition unit; 520 - first calculation unit; 530 - first processing unit; 540 - second processing unit. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be understood that the "system", "device" and / or "module" used in the present invention is a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0037] As shown in the present invention and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular, but also include the plural. In general, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.

[0038] Flowcharts are used in the present invention to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, the various steps may be processed in reverse order or simultaneously. At the same time, other operations may also be added to these processes, or one or more operations may be removed from these processes.

[0039] Example

[0040] The technology of soil and water erosion prevention and control in power transmission and transformation projects has become a research hotspot. Through sorting, it is found that soil and water erosion in power transmission and transformation projects has certain common characteristics. This common characteristic can help to select targeted solutions and strategies for subsequent soil and water erosion control. However, at present, this common characteristic will show the characteristics of "point and line" combination as a whole along the layout direction of the power transmission and transformation project. The soil and water erosion unit points are distributed in a panoramic discrete distribution. Therefore, when selecting prevention and control measures, they are also distributed in a discrete manner. In response to this situation, we are currently dividing the geographical location of the scope of the power transmission and transformation project lines, and each area is treated with soil and water control. Although this method solves the problem that it is difficult to arrange the prevention and control plan as a whole due to the scattered distribution, there will be a situation where a certain area involves multiple soil and water erosion situations, and the complexity and difficulty of the prevention and control measures will increase. Therefore, we currently use the common characteristics of some soil erosion unit points to cluster the discrete distribution. On the one hand, it reduces the difficulty of overall prevention and control planning, and on the other hand, it also reduces the complexity of the implementation of prevention and control measures. On this basis, we also found that some too scattered soil erosion unit points have similar soil erosion characteristics to concentrated soil erosion unit points, and can also be divided together to avoid omissions and the inability to take reasonable prevention and control measures. In response to the above ideas, we proposed a method for analyzing the regional characteristics of soil erosion in power transmission and transformation projects, which is mainly used to cluster and divide areas based on the common characteristics of soil erosion. On this basis, considering the characteristics of "points and lines" combined with discrete distribution, the two-point positioning method is also used to involve all erosion points of trunk lines and branch lines in the cluster analysis to avoid omissions.

[0041] Please refer to Figure 1 The present embodiment provides a method for analyzing regional characteristics of soil erosion in a power transmission and transformation project, comprising the following steps:

[0042] S100: Obtain the line laying information of the power transmission and transformation project, determine a number of soil erosion points based on the line laying information, classify the soil erosion points into types, and obtain a plurality of similar erosion unit groups; this step means first obtaining the line laying information of the entire erection and installation of the power transmission and transformation project. The line laying information generally crosses the hilly area. The overall project line is relatively long and will cross multiple soil erosion type areas. Therefore, these areas are located in the crossed soil erosion type areas as soil erosion points. Due to the construction characteristics of the power transmission and transformation project, these soil erosion type areas generally include four types of erosion unit points, namely, tower base area, construction road area, tensioning site construction area and crossing site construction area (these erosion unit points will change according to the construction stage). Therefore, they can be classified into types according to their construction areas, and soil erosion points of the same erosion type can be divided into one group, thereby obtaining a plurality of similar erosion unit groups.

[0043] S200: For each subset of the erosion unit group, a pairwise similarity comparison is performed, and two subsets whose similarity values ​​of soil erosion meet the preset value are merged into a preferred subset pair; this step means that a similarity comparison of soil erosion is performed for each erosion unit group (as a subset) included in the same erosion unit group. The soil erosion here refers to a parameter characterizing the degree of soil erosion, such as soil characteristic parameters, terrain characteristic parameters, vegetation coverage parameters, and climate environment parameters. The parameters corresponding to the same soil erosion are compared for similarity. If the comparison result (similarity value) meets the preset value (empirical value, configured according to demand), the two subsets are combined and merged into a preferred subset pair. It should be noted that any two subsets must be compared for similarity, including the case where one subset and multiple subsets form preferred subset pairs respectively, and then the associated points are selected for each preferred subset pair, that is, clustering is performed using the two-point positioning method to avoid omissions.

[0044] S300: Locate the first position information of the preferred subset pair in the line laying information, identify the associated erosion points of the preferred subset pair in the line laying information according to the first position information, determine the similarity between each associated erosion point and the soil erosion degree of the preferred subset pair, and merge the associated erosion points that meet the similarity threshold value with the preferred subset pair into a preferred set; this step means determining the similar point set of each group of preferred subset pairs, first determining the specific position of the preferred subset pair in the entire line laying information, recording the first position information, and identifying the associated erosion points in the entire line laying information according to the first position information. This identification method is mainly a method for screening other soil erosion points that the two subsets of the preferred subset pair pass through when they are directly connected by the shortest path on the line laying information. After obtaining all the associated erosion points, similarity judgment is performed on each associated erosion point one by one, that is, the similarity between each associated erosion point and the soil erosion degree of the preferred subset pair is determined, and the associated erosion points whose similarity meets the similarity threshold value (empirical value, configured according to demand) are directly merged with the two soil erosion points of the preferred subset pair into a preferred set. It should be noted that the method of judging the similarity of associated erosion points one by one can be consistent with the judgment method of comparing the water and soil erosion degrees of each subset in the erosion unit group by pairwise similarity, but it is necessary to adjust the similarity threshold value to screen similar associated erosion points.

[0045] Since the erosion unit points involved in the power transmission and transformation project are characterized by a combination of "points and lines" and discrete distribution, that is, the overall distribution is arranged along the transmission line, but there will be many branches on the main layout (the distance between the line tower bases varies from tens to hundreds of meters, and the construction roads, tensioning fields and crossing fields serving the tower base construction are also scattered around the line along with the tower base). In this embodiment, the line laying information includes a trunk line and at least one branch line. When identifying associated erosion points, it is necessary to consider how to determine the associated erosion points when similar water and soil erosion points are located on the branch lines to avoid clustering omissions. That is, in this embodiment, when identifying the associated erosion points of the preferred subset pair in the line laying information, if the two subsets of a preferred subset pair appear on two different branch lines respectively, all points passed by the shortest path of the main line passing through are determined as associated erosion points, wherein the shortest path of the main line passing through refers to the shortest main line segment connecting two branch lines. The consideration is that two branch lines are more likely to have the same points of soil and water erosion on the main line with close geographical locations, and such division is easier for zoning planning.

[0046] The preferred set formed in the above manner basically has similar typical characteristics of soil erosion, and then the area division begins, that is, step S400: based on the points involved in the preferred set, common areas are delineated in the line laying information, and the same common areas are integrated to obtain at least one prevention and control area; this step means marking all the points (soil erosion points) in each preferred set obtained according to the line laying information, and dividing the area according to the area involved in the line laying information related to all the points, thereby dividing a plurality of common areas, which can have the same common characteristics, and finally superimposing and integrating these common areas to obtain at least one larger prevention and control area, which, compared with the areas previously divided only according to the geographical location, have typical soil erosion area characteristics on the one hand, and will not be fragmented and increase the complexity of the prevention and control measures on the other hand.

[0047] Through the above technical scheme, firstly, based on the line laying information of the power transmission and transformation project, multiple soil and water erosion points are determined and classified to form multiple similar erosion unit groups; then, through pairwise similarity comparison, subsets with similar soil and water erosion degrees are merged into preferred subset pairs, and erosion points adjacent to or associated with them are further identified to ensure that there are no omissions; on this basis, related erosion points are screened and merged according to the similarity of soil and water erosion degrees to form a preferred set with similar soil and water erosion characteristics; finally, based on these preferred sets, prevention and control areas with common soil and water loss characteristics are delineated and integrated, which can not only accurately identify and integrate soil and water erosion points, effectively improve the pertinence and efficiency of soil and water conservation work, but also accurately reflect the actual soil and water loss situation along the power transmission and transformation project, which is conducive to formulating more scientific and reasonable soil and water conservation measures, reducing resource waste and improving prevention and control effects.

[0048] Considering that when performing pairwise similarity comparison of the water and soil erosion degree of each subset in the erosion unit group, the similarity meets the requirement of high similarity, then when judging the similarity between each associated erosion point and the preferred subset for water and soil erosion degree, it is necessary to lower the similarity requirement (lower similarity threshold value), otherwise too few associated erosion points will be identified, which will lead to excessive fragmentation of the later prevention and control area division, and on this basis, further compatibility is required for the similarity judgment of associated erosion points, that is, in this embodiment, the similarity between each associated erosion point and the preferred subset for water and soil erosion degree is judged, and the associated erosion points exceeding the similarity threshold value are merged with the preferred subset into a preferred set, which specifically includes the following steps:

[0049] The similarity of soil and water erosion degree of each associated erosion point is judged with the two subsets of the preferred subset pair one by one, that is, each associated erosion point is judged with the two subsets in turn for similarity. If the comparison result exceeds the similarity threshold value when compared with any of the two subsets of the preferred subset pair, the associated erosion point is considered to belong to a similar associated erosion point, that is, the associated erosion point is merged into the preferred set. Therefore, when judging the similarity of soil and water erosion degree of each associated erosion point with the preferred subset pair, a more relaxed standard is adopted, that is, as long as the similarity of the associated erosion point with any subset of the preferred subset pair exceeds the preset lower threshold value, it can be regarded as a similar associated erosion point and merged into the preferred set. This method not only increases the number of associated erosion point identifications and avoids excessive fragmentation of the division of prevention and control areas, but also enhances the adaptability and compatibility to the changes in soil and water erosion characteristics under different conditions, thereby ensuring the effectiveness and rationality of soil and water conservation measures.

[0050] On the basis of the above technical solution, the similarity judgment of water and soil erosion degree between each associated erosion point and the two subsets of the preferred subset pair can be performed using the following calculation model:

[0051] The similarity between the associated erosion point P and the subset A of the preferred subset pair is judged:

[0052]

[0053] The similarity between the associated erosion point P and the subset B of the preferred subset pair is judged:

[0054]

[0055] In formula (1) and formula (2), p=(p 1 , p 2 , ..., p n ) is the eigenvector of the associated erosion point P; a=(a 1 , a 2 , ..., a n ) is the eigenvector of subset A; b=(b 1 , b 2 , ..., b n ) is the eigenvector of subset B.

[0056] In this embodiment, the eigenvector p, the eigenvector a and the eigenvector b are all numerical groups obtained by normalizing or standardizing the soil and water erosion characteristics (minimum-maximum normalization or Z-score standardization), wherein the soil and water erosion characteristics include at least one of soil type, slope, vegetation coverage, rainfall or runoff rate.

[0057] After calculating the similarity between each associated erosion point P and subsets A and B according to the above formula, they are compared according to the set similarity threshold. If any comparison result meets the similarity threshold, the two are judged to be similar. For example, the feature vector of the associated erosion point P: p = (0.3, 0.7, 0.5, 0.2); the feature vector of subset A: a = (0.2, 0.6, 0.4, 0.1); the feature vector of subset B: b = (0.4, 0.8, 0.6, 0.3); the similarity threshold T = 0.5.

[0058] Then calculate the similarity between P and A:

[0059]

[0060] Then calculate the similarity between P and B:

[0061]

[0062] Because the similarities between P and subsets A and B are both less than T=0.5, P is merged with A and B into the preferred set.

[0063] Considering that there may be a large number of associated erosion points on the direct path in the preferred subset, if the associated erosion points are screened using the above similarity judgment method, most of the associated erosion points may meet the similarity threshold requirement, while a small number of associated erosion points may not meet it. At this time, if the small number of associated erosion points are formed into a separate prevention and control area, it will also lead to the problem of excessive regional fragmentation. To deal with this problem, please refer to Figure 2 The method further comprises the following steps after determining the similarity between each associated erosion point and the preferred subset for water and soil erosion degree, and merging the associated erosion points and the preferred subset pairs exceeding the similarity threshold into a preferred set:

[0064] S310: construct all the associated erosion points into a pre-subset group, mark the associated erosion points below the similarity threshold as low associated erosion points, and determine the number of the low associated erosion points; this step means first constructing a set of all the associated erosion points corresponding to the preferred subset pair in the line laying information as a pre-subset group, and determining the number of all subsets in the pre-subset group. Then, statistics are performed on the similarity results of all the associated erosion points in the pre-subset group, and the associated erosion points below the similarity threshold (which do not meet the similarity threshold requirements with any subset of the preferred subset pair) are marked as low associated erosion points, and then the number of the low associated erosion points is counted, and subsequent steps are performed.

[0065] S320: Calculate the ratio of the number of low-correlated erosion points to the total number of the pre-subset group. If the ratio is less than the preset ratio, all the low-correlated erosion points are incorporated into the preferred set. This step means calculating the ratio of the number of low-correlated erosion points obtained in step S310 to the total number of the pre-subset group to determine the proportion. If the calculated ratio is less than the preset ratio (empirical value, determined according to the fragmentation control requirements), in order to avoid the problem of excessive fragmentation, all the low-correlated erosion points are incorporated into the preferred set. Otherwise, they are not incorporated into the preferred set or are processed in other ways.

[0066] Through the above technical solution, strategies are used to optimize the screening of correlated erosion points and the division of prevention and control areas, and further analysis and judgment are carried out on the remaining low-correlated erosion points. If the proportion of low-correlated erosion points is small, in order to avoid excessive fragmentation, they can be incorporated into the preferred set to reduce regional segmentation problems, thereby improving prevention and control efficiency and maintaining regional integrity.

[0067] On the basis of the above scheme, although low-correlation erosion points can be incorporated into the preferred set to solve the problem of excessive fragmentation of the prevention and control area when their proportion is small, these low-correlation erosion points may be concentrated or scattered. If they are scattered, these low-correlation erosion points may have soil and water erosion similarities with their adjacent associated erosion points that meet the similarity threshold. However, if they are concentrated, these low-correlation erosion points may be in other typical features that characterize soil and water erosion, and other corresponding prevention and control measures need to be taken, which makes it inconvenient to merge them into the preferred set to form the same common area.

[0068] Please refer again for details Figure 2 , determining the number of the low correlation erosion points, and calculating the ratio of the number of the low correlation erosion points to the total number of the pre-subset group, further comprising the following steps:

[0069] S330: Obtain the second position information of each low-correlation erosion point in the line laying information, determine the interval distance between every two second position information, and calculate the number of interval distances greater than the preset distance. This step indicates that the interval distances of the low-correlation erosion points are analyzed, and their positions in the line laying information are further determined to determine whether they are concentrated distribution, that is, the interval distance between the second position information of every two low-correlation erosion points is determined. If the interval distance is greater than the preset distance (also an empirical value, which can be a multiple of the span distance of a water and soil erosion point), it is recorded, and finally the number of records is determined to determine the distribution form. If the number is greater than the preset ratio (empirical value, for example, 80%), it indicates a scattered distribution, and the step of incorporating all low-correlation erosion points into the preferred set is executed. Otherwise, it is a concentrated distribution, and the step of not incorporating all low-correlation erosion points into the preferred set is executed (the step of judging these low-correlation erosion points can be judged separately).

[0070] Through the above technical solution, low-correlation erosion points can be further analyzed and judged. Although a small number of low-correlation erosion points may not be highly correlated with the preferred set, if they are unevenly distributed (scattered distribution), the distance to the adjacent erosion points meets certain similarity standards and can be considered for merging; but if they are concentrated, they may have unique erosion characteristics and need to be processed separately. That is, by analyzing the interval distance and proportion of low-correlation erosion points in the line laying information to determine whether they are scattered or concentrated, the rationality of the division of prevention and control areas can be further improved or optimized.

[0071] Through the above technical solution, the selection and merging of the preferred sets can be reasonably analyzed and processed, and then the common areas can be divided based on each preferred set. At this time, the common areas obtained not only have typical common characteristics of soil erosion, but also cover an appropriate geographical range, which can facilitate targeted prevention and control management. On this basis, the common areas obtained may not overlap, overlap or completely overlap, so these common areas can be further integrated into prevention and control areas. For details, please refer to Figure 3 Based on the points involved in the preferred set, common areas are demarcated in the line laying information, and the common areas of the same type are integrated, which specifically includes the following steps:

[0072] S410: Obtain the third position information of each point involved in the preferred set, and concatenate all the third position information to form a common area of ​​the preferred set; this step means determining the position information (third position information) of all points (soil and water erosion points) included in each determined preferred set in the line laying information, and then connecting these third position information to obtain the path spanning range of the preferred set (for example, the preferred set points of the path are represented by solid lines, and the points of the path that do not pass through the preferred set are represented by dotted lines), and based on the path spanning range, the common area division is realized, that is, the geographical areas spanned by the points of the path itself are merged to obtain the common area. If the common area is continuous (continuous solid line), it can be represented by a single circle and the same identification (color outline, filled outline, etc.), and if it is non-continuous (including dotted line parts), it can be represented by multiple circles and the same identification (color outline, filled outline, etc.).

[0073] S420: Determine the degree of soil and water erosion of each point involved in the preferred set, and calculate typical parameters of soil and water erosion based on all soil and water erosion degree data as representative values ​​of the corresponding common areas; this step represents obtaining representative parameters of soil and water erosion for each common area in order to facilitate corresponding integration operations, first obtaining the degree of soil and water erosion of each point involved in the preferred set, and then calculating (for example, using the mean method) the typical parameters of soil and water erosion of the preferred set based on all soil and water erosion degree data, and the obtained typical parameters of soil and water erosion are used as representative values ​​of the common area, and subsequently similar common area identification operations are performed based on the representative values.

[0074] S430: Identify all common areas with representative values ​​in the same interval, and construct them into a group of common areas with the same attributes; this step means judging the numerical interval of the representative values ​​of all common areas, and constructing the common areas corresponding to the representative values ​​in the same interval into a group of common areas with the same attributes, in preparation for subsequent merging, that is, common areas in different intervals are established as different groups of common areas with the same attributes.

[0075] S440: Identify the overlapping parameters of the common areas in each of the common area groups with the same attributes, and determine whether the overlapping parameters are greater than the preset parameters. If the overlapping parameters are greater than the preset parameters, the common areas involved in the overlap will be merged into the control area, wherein the overlapping parameters include the overlapping positions and their overlapping areas. This step indicates that a merging operation is performed on the common area groups with the same attributes, and the common area groups within the common area groups with the same attributes are overlapped. The overlap identification can be judged based on the overlapping parameters, that is, the overlap situation within the entire common area group with the same attributes is judged based on the specific overlapping positions and their overlapping areas, and whether the overlapping parameters are greater than the preset parameters (empirical values, determined according to the fragmentation control requirements). If the overlapping parameters are greater than the preset parameters, the common areas involved in the overlap will be merged into the control area, that is, when the overlapping parameters are greater than the preset parameters, all the common areas involved in the overlapping positions will be merged to form a control area. The common areas in non-overlapping positions can be further judged whether a separate control area is required.

[0076] Through the above technical scheme, according to the third position information of the points in the preferred set, the common areas are determined, their connectivity is marked, and their representative values ​​are calculated. Then, according to these representative values, the common areas are classified into corresponding intervals, and the common areas with overlapping degrees greater than the preset parameters are merged to form prevention and control areas. This can effectively integrate the characteristics of soil and water erosion, divide targeted prevention and control areas, contribute to refined management, and avoid regional fragmentation.

[0077] Considering the low overlap in the common area group with the same attribute (the overlap parameter of each common area is low and cannot meet the preset parameter requirements), it is necessary to consider this situation to prevent the problem of excessive fragmentation of the prevention and control area. Then, based on the above technical solution, it is determined whether the overlap parameter is greater than the preset parameter. If the overlap parameter is greater than the preset parameter, the common area involved in the overlap is merged into the prevention and control area, and then the following steps are further included:

[0078] S450: If the overlap parameter is less than the preset parameter, the difference between the overlap parameter and the preset parameter is calculated, and the processing method for the common area is selected according to the difference value; this step indicates how to process the common area when low overlap occurs, and whether it is necessary to form a separate prevention and control area can be judged according to the difference with the preset parameter, that is, whether it is a low overlap or no overlap situation is judged according to the difference between the overlap parameter and the preset parameter.

[0079] When the difference value is less than the preset parameter, it is a low overlap situation. In this case, the overlapping area of ​​the common areas involved in the overlap will be identified. If the overlapping area is larger than the preset area (empirical value, the secondary guarantee value after the preset parameter), the common areas involved in the overlap will be merged into a prevention and control area. This processing means that when the overlap parameter is lower than the low overlap situation of the preset parameter, it is further determined which positions the overlapping common areas involved are. A secondary judgment of the overlapping area is made based on the common areas at these overlapping positions. The common areas that are larger than the preset area and involve overlap can be merged into prevention and control areas. The remaining non-overlapping common areas will not be merged to form a prevention and control area or undergo other processing.

[0080] When the difference value is equal to the preset parameter, it is a non-overlapping situation. Then, the step of whether each common area in the common area group with the same attribute forms a prevention and control area separately is entered. In this case, it is generally not merged with the common area group with the same attribute to form a prevention and control area. However, considering the fragmentation control problem, it is further judged whether there are problems of similar intervals and soil erosion characteristics in the non-overlapping common areas, that is, the subsequent judgment steps are carried out:

[0081] When the difference value is equal to the preset parameter, the interval distance between each two groups of common areas in the same attribute common area group is judged, and the representative value difference judgment is performed on the two groups of common areas whose interval distance is less than the preset interval value (empirical value, set as needed); if the representative value difference is less than the preset difference (empirical value, set as needed), the common areas that meet the preset interval value and representative value difference requirements are merged into prevention and control areas; this step means that in non-overlapping groups of common areas with the same attribute, all non-overlapping common areas are judged for interval distance, common areas with similar intervals are judged for representative value difference, and common areas with similar intervals and smaller difference values ​​are merged to form prevention and control areas, so as to control the problem of regional fragmentation.

[0082] Through the above technical solution, further processing will be carried out for low overlap (including no overlap) situations: when there is low overlap, the relevant overlapping common areas will be merged as prevention and control areas; when there is no overlap, the proximity and characteristic consistency of the common areas will be considered to ensure that in low overlap and no overlap situations, the common areas are merged through refined judgment to improve the prevention and control effect and optimize the regional division.

[0083] This embodiment also provides a system 500 for analyzing regional characteristics of soil erosion in power transmission and transformation projects. Figure 4The modular schematic diagram of the system 500 for analyzing regional characteristics of water and soil erosion in power transmission and transformation projects is mainly used to divide the functional modules of the system 500 for analyzing regional characteristics of water and soil erosion in power transmission and transformation projects according to the embodiment of the above method. For example, each functional module can be divided, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the present invention is schematic and is only a logical functional division. There may be other division methods in actual implementation. For example, in the case of dividing each functional module according to each function, Figure 4 What is shown is only a schematic diagram of a system / device, wherein the power transmission and transformation project soil erosion regional characteristic analysis system 500 may include a first acquisition unit 510, a first calculation unit 520, a first processing unit 530 and a second processing unit 540. The functions of each unit module are described below.

[0084] A first acquisition unit 510 is used to acquire line laying information of a power transmission and transformation project, determine a plurality of water and soil erosion points based on the line laying information, classify the plurality of water and soil erosion points into types, and obtain a plurality of similar erosion unit groups, wherein the line laying information includes a trunk road and at least one branch road;

[0085] A first calculation unit 520 is used to perform a pairwise similarity comparison on the water and soil erosion degree of each subset in each erosion unit group, and combine two subsets whose water and soil erosion degree similarity values ​​meet a preset value into a preferred subset pair;

[0086] The first processing unit 530 is used to locate the first position information of the preferred subset pair in the route laying information, identify the associated erosion points of the preferred subset pair in the route laying information according to the first position information, judge the similarity of each associated erosion point with the water and soil erosion degree of the preferred subset pair, and merge the associated erosion points and the preferred subset pair that meet the similarity threshold value into a preferred set; wherein, when identifying the associated erosion points of the preferred subset pair in the route laying information, if two subsets of a preferred subset pair appear on two different branch roads respectively, all points passed on the shortest path of the main route are determined as associated erosion points; in some embodiments, the first processing unit 530 is also used to judge the similarity of water and soil erosion degree of each associated erosion point with the two subsets of the preferred subset pair one by one, and if the similarity is with the two subsets of the preferred subset pair, If any one of the subsets is compared and the comparison result exceeds the similarity threshold, the associated erosion point is merged into the preferred set; and it is also used to construct all the associated erosion points into a pre-subset group, mark the associated erosion points below the similarity threshold as low-associated erosion points, determine the number of low-associated erosion points, calculate the ratio of the number of low-associated erosion points to the total number of the pre-subset group, and if the ratio is less than a preset ratio, all the low-associated erosion points are merged into the preferred set; it is also used to obtain the second position information of each low-associated erosion point in the line laying information, determine the interval distance between each two second position information, calculate the number of interval distances greater than the preset distance, and if the number is greater than the preset ratio, execute the step of merging all the low-associated erosion points into the preferred set, otherwise execute the step of not merging all the low-associated erosion points into the preferred set.

[0087] The second processing unit 540 is configured to delineate common areas in the line laying information based on the points involved in the preferred set, integrate the common areas of the same type, and obtain at least one prevention and control area. In some embodiments, the second processing unit 540 is also configured to obtain the third position information of each point involved in the preferred set, concatenate all the third position information to form the common area of ​​the preferred set; determine the degree of soil and water erosion of each point involved in the preferred set, calculate typical parameters of soil and water erosion based on all soil and water erosion degree data, and use them as representative values ​​of the corresponding common areas; identify all common areas with the same representative value in the same interval, and construct them into a group of common areas with the same attributes; identify the overlapping parameters of the common areas in each group of common areas with the same attributes, and determine whether the overlapping parameters are greater than the preset parameters. If the overlapping parameters are greater than the preset parameters, The common areas involved in the overlap are merged into the prevention and control area, wherein the overlap parameter includes the overlap position and its overlap area; it is also used to calculate the difference between the overlap parameter and the preset parameter if the overlap parameter is less than the preset parameter, and select the processing method for the common area according to the difference value; and it is used to judge when the difference value is equal to the preset parameter, judge the interval distance between each two groups of common areas with the same attribute in the common area group, and judge the representative value difference of the two groups of common areas with an interval distance less than the preset interval value; if the representative value difference is less than the preset difference, the common areas that meet the preset interval value and representative value difference requirements are merged into the prevention and control area.

[0088] In the above embodiments, the more specific working process of each functional unit can refer to the corresponding content disclosed in the aforementioned method embodiment. In addition, each functional unit can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired or wireless means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state hard disk (sol-identified state disk, SSD)), etc.

[0089] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0090] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0091] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0092] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for analyzing regional characteristics of soil erosion in power transmission and transformation projects, characterized in that: The steps include: Acquire line laying information of a power transmission and transformation project, determine a number of water and soil erosion points based on the line laying information, classify the number of water and soil erosion points into types, and obtain a plurality of erosion unit groups of the same type; Performing pairwise similarity comparison on the water and soil erosion degree of each subset in each erosion unit group, and merging two subsets whose water and soil erosion degree similarity values ​​meet a preset value into a preferred subset pair; Locating first position information of the preferred subset pair in the route laying information, identifying associated erosion points of the preferred subset pair in the route laying information according to the first position information, determining similarity between each associated erosion point and the water and soil erosion degree of the preferred subset pair, and merging the associated erosion points and the preferred subset pair that meet a similarity threshold into a preferred set; Based on the points involved in the preferred set, common areas are delineated in the line laying information, and similar common areas are integrated to obtain at least one prevention and control area; The line laying information includes a trunk line and at least one branch line. When identifying the associated erosion points of the preferred subset pair in the line laying information, if two subsets of a preferred subset pair appear on two different branch lines respectively, all points passed on the shortest path of the trunk line are determined as associated erosion points.

2. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 1 is characterized in that: The step of judging the similarity between each associated erosion point and the preferred subset pair in terms of water and soil erosion degree, and merging the associated erosion points exceeding the similarity threshold value with the preferred subset pair into a preferred set specifically comprises the following steps: judging the similarity between the water and soil erosion degree of each associated erosion point and the two subsets of the preferred subset pair one by one, and if the comparison result with either of the two subsets of the preferred subset pair exceeds the similarity threshold value, merging the associated erosion point into the preferred set.

3. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 2 is characterized in that: The similarity judgment of water and soil erosion degree between each associated erosion point and the two subsets of the preferred subset pair is performed one by one using the following calculation model: The similarity between the associated erosion point P and the subset A of the preferred subset pair is judged: ; （1） The similarity between the associated erosion point P and the subset B of the preferred subset pair is judged: ; （2） In formula (1) and formula (2), is the eigenvector of the associated erosion point P; is the eigenvector of subset A; is the eigenvector of subset B.

4. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 3 is characterized in that: Eigenvector , eigenvector and the eigenvector They are all value groups obtained by normalizing or standardizing soil and water erosion characteristics, wherein the soil and water erosion characteristics include at least one of soil type, slope, vegetation coverage, rainfall or runoff rate.

5. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 2 is characterized in that: The step of determining the similarity between each associated erosion point and the preferred subset of water and soil erosion degree, and merging the associated erosion points exceeding the similarity threshold and the preferred subset into a preferred set further includes the following steps: All the associated erosion points are constructed into a pre-subset group, the associated erosion points below the similarity threshold are marked as low-associated erosion points, the number of the low-associated erosion points is determined, and the ratio of the number of low-associated erosion points to the total number of the pre-subset group is calculated. If the ratio is less than a preset ratio, all the low-associated erosion points are incorporated into the preferred set.

6. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 5, characterized in that: After determining the number of the low correlation erosion points and calculating the ratio of the number of the low correlation erosion points to the total number of the pre-subset group, the following steps are also included: The second position information of each of the low-correlation erosion points in the line laying information is obtained, the interval distance between each two second position information is determined, and the number of interval distances greater than a preset distance is calculated. If the number is greater than a preset ratio, the step of incorporating all the low-correlation erosion points into the preferred set is executed; otherwise, the step of not incorporating all the low-correlation erosion points into the preferred set is executed.

7. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 1 or 6, characterized in that: The step of demarcating common areas in the line laying information based on the points involved in the preferred set and integrating similar common areas specifically includes the following steps: Obtain the third position information of each point involved in the preferred set, and concatenate all the third position information to form a common area of ​​the preferred set; determine the water and soil erosion degree of each point involved in the preferred set, and calculate typical parameters of water and soil erosion based on all water and soil erosion degree data as representative values ​​of the corresponding common areas; identify all common areas with the same representative value interval, and construct them into a group of common areas with the same attributes; identify the overlapping parameters of the common areas in each group of common areas with the same attributes, and determine whether the overlapping parameters are greater than a preset parameter. If the overlapping parameters are greater than the preset parameters, the common areas involved in the overlap are merged into the prevention and control area, wherein the overlapping parameters include overlapping positions and overlapping areas.

8. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 7, characterized in that: The method further comprises the following steps: if the overlap parameter is less than the preset parameter, calculating the difference between the overlap parameter and the preset parameter, and selecting a processing method for the common area according to the difference; When the difference value is less than the preset parameter, the overlapping area of ​​the common areas involved in the overlap is identified. If the overlapping area is greater than the preset area, the common areas involved in the overlap are merged into a prevention and control area. When the difference value is equal to the preset parameter, the process proceeds to the step of determining whether each common area in the group of common areas with the same attributes forms a separate prevention and control area.

9. The method for analyzing regional characteristics of soil erosion in power transmission and transformation projects according to claim 8, characterized in that: When the difference value is equal to the preset parameter, the interval distance between each two groups of common areas in the same attribute common area group is judged, and the representative value difference of the two groups of common areas whose interval distance is less than the preset interval value is judged. If the representative value difference is less than the preset difference, the common areas that meet the preset interval value and representative value difference requirements are merged into prevention and control areas.

10. A system for analyzing regional characteristics of soil erosion in power transmission and transformation projects, characterized in that: include: A first acquisition unit is used to acquire line laying information of a power transmission and transformation project, determine a plurality of water and soil erosion points based on the line laying information, classify the plurality of water and soil erosion points into types, and obtain a plurality of similar erosion unit groups, wherein the line laying information includes a trunk road and at least one branch road; A first calculation unit is used to perform a pairwise similarity comparison on the water and soil erosion degree of each subset in each erosion unit group, and merge two subsets whose water and soil erosion degree similarity values ​​meet a preset value into a preferred subset pair; A first processing unit is used to locate the first position information of the preferred subset pair in the route laying information, identify the associated erosion points of the preferred subset pair in the route laying information according to the first position information, determine the similarity between each associated erosion point and the water and soil erosion degree of the preferred subset pair, and merge the associated erosion points and the preferred subset pair that meet the similarity threshold value into a preferred set; wherein, when identifying the associated erosion points of the preferred subset pair in the route laying information, if two subsets of a preferred subset pair appear on two different branch roads respectively, all points passed on the shortest path of the main route are determined as associated erosion points; The second processing unit demarcates common areas in the line laying information based on the points involved in the preferred set, and integrates the same type of common areas to obtain at least one prevention and control area.

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