A method for setting safety management scope of hydropower projects

Abstract

The present invention provides a method for setting the safety management scope of a hydropower project, comprising the following steps: traversing the input land acquisition red line polygon vector data, extracting the land acquisition red line polygon vector data of the land acquisition type being permanent land; obtaining the land acquisition red line polygon contour line, extracting the inflection point on the land acquisition red line polygon contour line, calculating the angle of the inflection point, the land use status classification data and the terrain slope, evaluating whether the inflection point is suitable as the boundary point of the hydropower project safety management scope, and analyzing whether the boundary point mark can be installed at the inflection point position. The present invention can automatically realize the rapid setting of the safety management scope of the hydropower project, effectively improve the setting efficiency of the boundary point, and reduce the user entry threshold.

Description

Technical Field

[0001] The invention belongs to the technical field of safety management scope boundary point location setting, and specifically relates to a method for setting the safety management scope of a hydropower project. Background Art

[0002] Under the guidance and implementation of the dual carbon goals, the hydropower industry has ushered in an opportunity for rapid development. Pumped storage has developed rapidly recently. In the operation and management of hydropower projects, the scope of project safety management should be implemented and the safety management responsibilities should be clarified. In the engineering design stage, boundary points are usually set at fixed intervals based on the permanent land acquisition red line, without considering the contour shape and direction of the red line. In the implementation stage, the location of the boundary points needs to be re-determined based on the actual situation. The setting of boundary points needs to consider many factors. At present, the boundary points are mainly set manually, which has the problem of low efficiency in setting boundary points. Summary of the invention

[0003] In view of the urgent need to solve the problems faced, the present invention provides a method for setting the safety management scope of a hydropower project, which can effectively solve the above problems.

[0004] The technical solution adopted by the present invention is as follows:

[0005] The present invention provides a method for setting a hydropower project safety management scope, comprising the following steps:

[0006] Step S1, inputting the hydropower project land acquisition red line polygon vector data; each land acquisition red line polygon has a land acquisition type attribute; the land acquisition type attribute includes two types: permanent land use and temporary land use;

[0007] Step S2, traversing the input land acquisition red line polygon vector data, extracting the land acquisition red line polygon vector data of permanent land acquisition type;

[0008] Step S3, for each extracted land acquisition red line polygon vector data of permanent land acquisition type, executing steps S4 to S10;

[0009] Step S4, traverse the surface elements formed by the land acquisition red line polygon vector data, obtain the land acquisition red line polygon contour line, extract the inflection point data on the land acquisition red line polygon contour line, and obtain the position coordinates of each inflection point, and number the inflection points in an incremental manner, Node i Indicates the number of the i-th inflection point, i = 1, 2, ..., n, n is the total number of inflection points on the polygonal contour line of the land acquisition red line, inflection point Node i The coordinates are recorded as (x i ,y i );

[0010] Step S5: Analyze and obtain the inflection point Node iThe two line segments connected to the polygonal contour line of the land acquisition red line, and the line segments on each line segment connected to the inflection point Node i Non-overlapping inflection points j 、Node k , where j = 1, 2, ..., n, k = 1, 2, ..., n, and i ≠ j ≠ k;

[0011] Step S6, inflection point Node i and inflection point Node j The connected line segment is L ij , inflection point Node i and inflection point Node k The connected line segment is L ik , calculate the line segment L ij and line segment L ik At the turning point i The angle α of the position i ;

[0012] Step S7, analyze and obtain the inflection point Node i Classification of land use status;

[0013] Step S8, analyze and obtain the inflection point Node i Slope i ;

[0014] Step S9, for the inflection point Node i The angle α i , land use classification and terrain slope i Conduct a comprehensive assessment to evaluate the inflection point Node i Is it suitable as the boundary point of the hydropower project safety management scope? At the same time, analyze the inflection point Node i Whether the location can be used to set up boundary points and stakes;

[0015] Step S10, executing steps S5 to S9 for n inflection points, obtaining multiple boundary points on each land acquisition red line polygonal contour, connecting the multiple boundary points to form a closed area, which is the safety management scope of the hydropower project.

[0016] Preferably, step S5 is specifically:

[0017] Step S5.1, interrupt the polygonal contour line of the land acquisition red line at each turning point, thereby obtaining multiple line segments; number each line segment in an incremental manner, Line w represents the number of the w-th line segment, w = 1, 2, ..., W, W is the total number of line segments;

[0018] Step S5.2, spatially connecting the line segments and the inflection points to obtain two inflection points connected to each line segment, thereby obtaining a spatial positional relationship between the line segments and the inflection points, and further obtaining a line segment association result;

[0019] Step S5.3, spatially connect the inflection point with the line segment association result of step S5.2 to obtain a set of inflection points on each inflection point and the line segment connected to it;

[0020] Step S5.4, traverse each inflection point Node i , get each inflection point Node i All other inflection point data connected to it are deduplicated from all other inflection point data, and the remaining two inflection point data are the inflection point Node i The inflection point at the other end of two adjacent line segments is the inflection point Node j and inflection point Node k .

[0021] Preferably, step S6 specifically comprises:

[0022] Step S6.1, inflection point Node i The position coordinates are (x i ,y i );Inflection pointNode j The position coordinates are (x j ,y j );Inflection pointNode k The position coordinates are (x k ,y k );

[0023] Step S6.2, use formula 1 to get the inflection point Node i To the turning point Node j A vector, that is: vector Node i Node j :

[0024] VectorNode i Node j =(x j -x i ,y j -y i ) Formula 1 uses Formula 2 to get the inflection point Node i To the turning point Node k A vector, that is: vector Node i Node k :

[0025] VectorNode i Node k =(x k -x i,y k -y i ) Formula 2

[0026] Using formula 3, we get the vector Node i Node j and vectorNode i Node k The product of:

[0027] VectorNode i Node j Vector Node i Node k =(x j -x i )×(x k -x i )+(y j -y i )×(y k -y i )Formula 3

[0028] Using formula 4, we get the inflection point Node i To the turning point Node j Distance|Node i Node j |, which is the line segment L ij Length:

[0029]

[0030] Using formula 5, we get the inflection point Node i To the turning point Node k Distance|Node i Node k |, which is the line segment L ik Length:

[0031]

[0032] Using formula 6, we get line segment L ij and line segment L ik At the turning point i The angle N in radians of the position i :

[0033] N i =arccos(vectorNode i Node j Vector Node i Node k ) / (|Node i Node j |×|Nodei Node k |)

[0034] Formula 6

[0035] Using formula 7, we get line segment L ij and line segment L ik At the turning point i The angle α of the position i , where the angle α i The unit of is degrees:

[0036] α i =(180.0×N i ) / PI Formula 7

[0037] Among them: PI is π.

[0038] Preferably, step S7 specifically includes:

[0039] Step S7.1, input the land use status classification data of the land acquisition scope of the hydropower project; use the following formula to obtain the half of the square root of the minimum plot area Min_MJ as the grid cell size Cell_Size, and perform grid processing on the land use status classification data;

[0040]

[0041] Step S7.2, for each grid, take the land use status classification unique identification code BSM as the grid unit value, use the scan line seed point filling algorithm to realize the rasterization of vector data, obtain the land use status classification unique identification code BSM of each grid, and obtain the first layer in which each grid has the land use status classification unique identification code BSM;

[0042] Step S7.3, for the inflection point Node i The coordinates (x i ,y i ) and the angle α i The second layer uses the same grid cell size Cell_Size for rasterization, and the following formula is used to obtain each inflection point Node i The row number of the grid cell H i and column number L i :

[0043]

[0044] Where: (x0, y0) represents the coordinates of the lower left corner of the first layer;

[0045] Step S7.4, performing position overlap analysis on the first layer obtained in step S7.2 and the second layer obtained in step S7.3, and obtaining each inflection point Node i The unique identification code of land use status classification BSM can be obtained for each inflection point Node i Classification of land use status.

[0046] Preferably, step S8 is specifically:

[0047] Step S8.1, input DEM data;

[0048] Step S8.2, for the inflection point Node i , obtain the elevation of each pixel in its eight neighborhoods, namely: the elevation of the upper left pixel a is El(a), the elevation of the upper pixel b is El(b), the elevation of the upper right pixel c is El(c), the elevation of the left pixel d is El(d), the elevation of the right pixel f is El(f), the elevation of the lower left pixel g is El(g), the elevation of the lower pixel h is El(h), and the elevation of the lower right pixel I is El(I);

[0049] Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the x direction dz / dx:

[0050] dz / dx=((El(c)+2El(f)+El(I))-(El(a)+2El(d)+El(g))) / (8×x_cellsize)

[0051] Among them: x_cellsize represents the size of each pixel in the x direction;

[0052] Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the y direction dz / dy:

[0053] dz / dy=((El(g)+2El(h)+El(I))-(El(a)+2El(b)+El(c))) / (8×y_cellsize)

[0054] Among them: y_cellsize represents the size of each pixel in the y direction;

[0055] Step S8.4, use the following formula to get the inflection point Node i Slope i :

[0056]

[0057] So far, we get the inflection point Node iSlope i .

[0058] The method for setting the safety management scope of a hydropower project provided by the present invention has the following advantages:

[0059] The present invention can automatically realize the rapid setting of the safety management scope of the hydropower project, effectively improve the setting efficiency of the boundary points, and lower the entry threshold for users. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A schematic diagram of a flow chart of a method for setting a hydropower project safety management scope provided by the present invention;

[0061] Figure 2 The graphical form of the land acquisition red line polygonal vector data provided by the present invention;

[0062] Figure 3 A polygonal map of the red line of the permanent land provided by the present invention;

[0063] Figure 4 A schematic diagram of obtaining the turning point of the land acquisition red line provided by the present invention;

[0064] Figure 5 A schematic diagram of the polygonal contour line of the land acquisition red line being interrupted by the turning point provided by the present invention;

[0065] Figure 6 The angle α provided by the present invention is i Schematic diagram of calculation;

[0066] Figure 7 The example result map of rasterization of land use status classification data provided by the present invention;

[0067] Figure 8 The terrain slope calculation principle diagram provided by the present invention;

[0068] Fig. 9 A schematic diagram of obtaining the inflection point slope provided by the present invention;

[0069] Fig.10 The example data 1 provided by the present invention is a result diagram of boundary point setting;

[0070] Fig.11 The example data 2 provided by the present invention is the result diagram of boundary point setting;

[0071] Fig.12 The example data 3 provided by the present invention is the result diagram of boundary point setting;

[0072] Fig.13 The example data 4 provided by the present invention is the result diagram of boundary point setting;

[0073] Fig.14 This is a diagram of the result of setting boundary points of example data 5 provided by the present invention. DETAILED DESCRIPTION

[0074] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0075] The present invention aims to adopt spatial data processing and analysis technology, combined with the actual needs of setting the safety management scope of hydropower projects, based on the permanent land acquisition red line data in the planning and design stage of hydropower projects, and comprehensively considers factors such as the angle of boundary points, land use status classification, and terrain slope, to form a method for setting the safety management scope of hydropower projects. Users only need to input the land acquisition red line data according to the process, set the process data and the final output position according to the rules, and can automatically realize the rapid setting of the safety management scope of hydropower projects. The present invention can effectively improve the setting efficiency of the boundary points of the safety management scope and reduce the entry threshold for users.

[0076] The present invention provides a method for setting the safety management scope of a hydropower project. The main idea is as follows: the present invention uses the polygonal vector data of the land acquisition red line of the hydropower project as input data, screens out the land acquisition red line data of the permanent land, traverses each surface element of the land acquisition red line data of the permanent land in turn, obtains the contour line of the permanent land acquisition red line surface element, extracts the inflection points on the line, encodes the inflection points, adds the inflection point coordinates (x, y), determines the line segments adjacent to each inflection point through the spatial position relationship, associates and obtains a set of inflection points on the line segments connected to the inflection points that do not overlap with the inflection points, and knows the coordinates of the two inflection points that are connected to each inflection point and do not overlap with the inflection points. The radian of the inflection point angle is calculated by using the vector point set method, and then the radian is converted into degrees to obtain the angle of each inflection point; the inflection point angle rule is set to extract the preliminarily set boundary points; the preliminarily set boundary points are spatially associated with the land use status classification data to obtain the inflection point land use status classification; the terrain slope data is calculated through the digital elevation model within the hydropower project area, and it is spatially associated with the inflection point data on the permanent land acquisition red line to obtain the inflection point terrain slope; the boundary point position is finally set after analysis and comprehensive evaluation, and the permanent land acquisition red line surface is traversed in turn, and the above operations are repeated to obtain the boundary point setting results.

[0077] The method for setting the scope of safety management of a hydropower project provided by the present invention can lower the entry threshold for users. Users do not need to understand the internal implementation process of the method, nor do they need to have relevant professional knowledge background in spatial data processing and analysis. They only need to choose to input the land acquisition red line data and follow the process prompts to set the output position to automatically obtain the results of setting the boundary points of the safety management scope of the hydropower project, which effectively improves the setting efficiency of the boundary points, implements the safety management responsibilities of the hydropower project, and helps to improve the safety management and operation and maintenance level of the hydropower project.

[0078] The present invention provides a method for setting a hydropower project safety management scope, comprising the following steps:

[0079] Step S1, inputting the hydropower project land acquisition red line polygon vector data; each land acquisition red line polygon has a land acquisition type attribute; the land acquisition type attribute includes two types: permanent land use and temporary land use;

[0080] Step S2, traversing the input land acquisition red line polygon vector data, extracting the land acquisition red line polygon vector data of permanent land acquisition type;

[0081] Step S3, for each extracted land acquisition red line polygon vector data of permanent land acquisition type, executing steps S4 to S10;

[0082] Step S4, traverse the surface elements formed by the land acquisition red line polygon vector data, obtain the land acquisition red line polygon contour line, extract the inflection point data on the land acquisition red line polygon contour line, and obtain the position coordinates of each inflection point, and number the inflection points in an incremental manner, Node i Indicates the number of the i-th inflection point, i = 1, 2, ..., n, n is the total number of inflection points on the polygonal contour line of the land acquisition red line, inflection point Node i The coordinates are recorded as (x i ,y i );

[0083] Step S5: Analyze and obtain the inflection point Node i The two line segments connected to the polygonal contour line of the land acquisition red line, and the line segments on each line segment connected to the inflection point Node i Non-overlapping inflection points j 、Node k , where j = 1, 2, ..., n, k = 1, 2, ..., n, and i ≠ j ≠ k;

[0084] Step S6, inflection point Node i and inflection point Node j The connected line segment is L ij , inflection point Node i and inflection point Node kThe connected line segment is L ik , calculate the line segment L ij and line segment L ik At the turning point i The angle α of the position i。

[0085] Step S7, analyze and obtain the inflection point Node i Classification of land use status;

[0086] Step S8, analyze and obtain the inflection point Node i Slope i ;

[0087] Step S9, for the inflection point Node i The angle α i , land use classification and terrain slope i Conduct a comprehensive assessment to evaluate the inflection point Node i Is it suitable as the boundary point of the hydropower project safety management scope? At the same time, analyze the inflection point Node i Whether the location can be used to set up boundary points and stakes;

[0088] Step S10, executing steps S5 to S9 for n inflection points, obtaining multiple boundary points on each land acquisition red line polygonal contour, connecting the multiple boundary points to form a closed area, which is the safety management scope of the hydropower project.

[0089] A specific embodiment is described below:

[0090] Step S1, inputting the hydropower project land acquisition red line polygon vector data; each land acquisition red line polygon has a land acquisition type attribute; the land acquisition type attribute includes two types: permanent land use and temporary land use;

[0091] Specifically, Figure 2 As shown, it is a graphical form of the land acquisition red line polygon vector data; the land acquisition red line polygon vector data is in SHP format. The experimental data has a total of 51 records. The land acquisition red line types include permanent land and temporary land. There are 9 records for permanent land and 42 records for temporary land.

[0092] In addition, the land use status classification of each grid point within the scope of land acquisition for hydropower projects is also input. The data is in SHP format, and the land use status classification includes three categories: agricultural land, construction land, and unused land, with a total of 6499 records.

[0093] The digital elevation model (DEM) of the land acquisition scope of the hydropower project is also input. The data is in TIF format, including 952 rows and 1707 columns.

[0094] Step S2, traversing the input land acquisition red line polygon vector data, extracting the land acquisition red line polygon vector data of permanent land acquisition type;

[0095] Specifically, traverse the polygonal vector data of the land acquisition red line and select the data of the land acquisition red line type as permanent land type. The extraction result is as follows Figure 3 As shown, the grey area is the red line polygon for permanent land acquisition.

[0096] Step S3, for each extracted land acquisition red line polygon vector data of permanent land acquisition type, executing steps S4 to S10;

[0097] Step S4, traverse the surface elements formed by the land acquisition red line polygon vector data, obtain the land acquisition red line polygon contour line, extract the inflection point data on the land acquisition red line polygon contour line, and obtain the position coordinates of each inflection point, and number the inflection points in an incremental manner, Node i Indicates the number of the i-th inflection point, i = 1, 2, ..., n, n is the total number of inflection points on the polygonal contour line of the land acquisition red line, inflection point Node i The coordinates are recorded as (x i ,y i );

[0098] Specifically, according to the SHP data storage format, the (X, Y) coordinates of the inflection points on each land acquisition red line polygonal contour line are read in turn to obtain the red line inflection point data, and a total of 6886 inflection points are obtained, such as Figure 4 The figure below shows the schematic diagram after obtaining the inflection point of the red line. Each inflection point is numbered in the form of "Node+Num". For example, Node1, Node2, ..., NodeNum, where Num is the total number of inflection points, and the X and Y coordinate information of the inflection point is added.

[0099] Step S5: Analyze and obtain the inflection point Node i The two line segments connected to the polygonal contour line of the land acquisition red line, and the line segments on each line segment connected to the inflection point Node i Non-overlapping inflection points j 、Node k , where j = 1, 2, ..., n, k = 1, 2, ..., n, and i ≠ j ≠ k;

[0100] Specifically, each inflection point is used to interrupt the polygonal contour of the land acquisition red line to obtain line segment data, and a total of 3443 line segments are obtained; each line segment is numbered in the form of "Line+Num", such as Line1, Line2,..., LineNum, where Num is the total number of line segments. The line segments are spatially connected with the inflection points to obtain the inflection points connected to each line segment, thereby obtaining the spatial position relationship between the line segments and the inflection points, and then obtaining the line segment association results; the inflection point data is then spatially connected with the above line segment association results to obtain all the inflection points connected to each inflection point, and the connection records with consistent inflection point coordinates among all inflection points are deleted, leaving two records, which are the inflection points at the other ends of the two adjacent line segments.

[0101] Take one of the records with 9 inflection point data as an example. Figure 5 As shown in the figure, it is a schematic diagram of the polygonal contour line of the land acquisition red line being interrupted by the turning point; as shown in Table 1, it is an example of obtaining the turning point result at the other end of two adjacent line segments of the turning point:

[0102] Table 1: Example of obtaining the inflection point at the other end of two adjacent line segments

[0103] POINT_X POINT_Y POINT_X1 POINT_Y1 POINT_X2 POINT_Y2 2525.917 3967.514 2519.068 3960.024 2511.467 3982.016 2519.068 3960.024 2525.917 3967.514 2512.625 3962.455 2512.625 3962.455 2519.068 3960.024 2508.299 3964.370 2508.299 3964.370 2512.625 3962.455 2504.188 3966.415 2504.188 3966.415 2508.299 3964.370 2496.933 3970.459 2496.933 3970.459 2504.188 3966.415 2493.220 3972.812 2493.220 3972.812 2496.933 3970.459 2491.582 3973.915 2491.582 3973.915 2493.220 3972.812 2511.467 3982.016 2511.467 3982.016 2491.582 3973.915 2525.917 3967.514

[0104] Step S6, inflection point Node i and inflection point Node j The connected line segment is L ij , inflection point Node i and inflection point Node k The connected line segment is L ik , calculate the line segment L ij and line segment L ik At the turning point i The angle α of the position i .

[0105] Step S6 is specifically as follows:

[0106] Step S6.1, inflection point Node i The position coordinates are (x i ,y i );Inflection pointNode j The position coordinates are (x j ,y j );Inflection pointNode k The position coordinates are (x k ,y k );

[0107] Step S6.2, use formula 1 to get the inflection point Node i To the turning point Node j A vector, that is: vector Node iNode j :

[0108] VectorNode i Node j =(x j -x i ,y j -y i ) Formula 1 uses Formula 2 to get the inflection point Node i To the turning point Node k A vector, that is: vector Node i Node k :

[0109] VectorNode i Node k =(x k -x i ,y k -y i ) Formula 2

[0110] Using formula 3, we get the vector Node i Node j and vectorNode i Node k The product of:

[0111] VectorNode i Node j Vector Node i Node k =(x j -x i )×(x k -x i )+(y j -y i )×(y k -y i )Formula 3

[0112] Using formula 4, we get the inflection point Node i To the turning point Node j Distance|Node i Node j |, which is the line segment L ij Length:

[0113]

[0114] Using formula 5, we get the inflection point Node i To the turning point Node k Distance|Node i Node k |, which is the line segment Lik Length:

[0115]

[0116] Using formula 6, we get line segment L ij and line segment L ik At the turning point i The angle N in radians of the position i :

[0117] N i =arccos(vectorNode i Node j Vector Node i Node k ) / (|Node i Node j |×|Node i Node k |)

[0118] Formula 6

[0119] Using formula 7, we get line segment L ij and line segment L ik At the turning point i The angle α of the position i , where the angle α i The unit of is degrees:

[0120] α i =(180.0×N i ) / PI Formula 7

[0121] Among them: PI is π.

[0122] For ease of understanding, Figure 6 As shown, it is the angle α i A calculation diagram of .

[0123] For the convenience of explanation, Figure 6 Inflection point Node i It is represented by point A, whose position coordinates are (x1, y1); the inflection point Node j It is represented by point B, whose position coordinates are (x2, y2); the inflection point Node k Represented by point C, its position coordinates are (x3, y3); use the vector calculation method to calculate the angle α, the calculation process is as follows:

[0124] Vector AB = (x2-x1, y2-y1) Formula 1

[0125] Vector AC = (x3-x1, y3-y1) Formula 2

[0126] AB·AC=(x2-x1)×(x3-x1)+(y2-y1)×(y3-y1) Formula 3

[0127]

[0128] cos∠A=(AB·AC) / (|AB|×|AC|) Formula 6

[0129] ∠A=arccos(AB·AC) / (|AB|×|AC|) Formula 7

[0130] α=(180.0×∠A) / PI Formula 8

[0131] Where ∠A is in radians, angle α is in degrees, and PI is π.

[0132] In this embodiment, the calculation results are shown in Table 2:

[0133] Table 2: Example of angle calculation results

[0134]

[0135] Therefore, the inflection point angles of all records are obtained by looping through each permanent red line record.

[0136] Step S7, analyze and obtain the inflection point Node i Classification of land use status;

[0137] Step S7 is specifically as follows:

[0138] Step S7.1, input the land use status classification data of the land acquisition scope of the hydropower project; use the following formula to obtain the half of the square root of the minimum plot area Min_MJ as the grid cell size Cell_Size, and perform grid processing on the land use status classification data;

[0139]

[0140] By traversing the land use status classification data, we can see that Min_MJ is 61.8m 2 , Cell_Size = 3, the rasterization example results are as follows Figure 7 shown.

[0141] Step S7.2, for each grid, take the land use status classification unique identification code BSM as the grid unit value, use the scan line seed point filling algorithm to realize the rasterization of vector data, obtain the land use status classification unique identification code BSM of each grid, and obtain the first layer in which each grid has the land use status classification unique identification code BSM;

[0142] The specific steps of this step are:

[0143] The first step is to select a grid with a unique land use classification code BSM, whose coordinates are (x, y), use it as a seed point Seed (x, y), and store it in the stack.

[0144] In the second step, if the stack is empty, the algorithm ends, otherwise execute the third step.

[0145] The third step is to take out the top element of the stack as the seed point (x, y) of the current scan line, where y is the current scan line;

[0146] Starting from the seed point (x, y), fill in the left and right directions along the current scan line until the boundary. Mark the left and right endpoints of the segment as xLeft and xRight respectively;

[0147] The fourth step is to scan the previous and next rows of the third step, and check whether all of them are boundary points or filled points within the range of xLeft≤x≤xRight. If not, the rightmost position of each segment to be filled is stored in the stack as a new seed point.

[0148] Step 5. Return to step 2.

[0149] Through this step, the area with the land use status classification unique identification code BSM can be quickly located, that is, the colored area, and each grid in the area has the land use status classification unique identification code BSM.

[0150] Step S7.3, for the inflection point Node i The coordinates (x i ,y i ) and the angle α i The second layer uses the same grid cell size Cell_Size for rasterization, and the following formula is used to obtain each inflection point Node i The row number of the grid cell H i and column number L i :

[0151]

[0152] Where: (x0, y0) represents the coordinates of the lower left corner of the first layer;

[0153] Step S7.4, performing position overlap analysis on the first layer obtained in step S7.2 and the second layer obtained in step S7.3, thereby obtaining each inflection point Node i The unique identification code of land use status classification BSM can be obtained for each inflection point Node iLand use status classification. The sample results are shown in Table 3.

[0154] Table 3: Example of classification of land use status at inflection points

[0155] PnameId POINT_X POINT_Y TDLYXZFL Node1 2525.917 3967.514 Arbor woodland Node2 2519.068 3960.024 River water surface Node3 2512.625 3962.455 River water surface Node4 2508.299 3964.370 Arbor woodland Node5 2504.188 3966.415 River water surface Node6 2496.933 3970.459 Arbor woodland Node7 2493.220 3972.812 River water surface Node8 2491.582 3973.915 River water surface Node9 2511.467 3982.016 Arbor woodland

[0156] Step S8, analyze and obtain the inflection point Node i Slope i ;

[0157] Step S8 is specifically as follows:

[0158] Step S8.1, input DEM data;

[0159] Step S8.2, for the inflection point Node i , obtain the elevation of each pixel in its eight neighborhoods, namely: the elevation of the upper left pixel a is El(a), the elevation of the upper pixel b is El(b), the elevation of the upper right pixel c is El(c), the elevation of the left pixel d is El(d), the elevation of the right pixel f is El(f), the elevation of the lower left pixel g is El(g), the elevation of the lower pixel h is El(h), and the elevation of the lower right pixel I is El(I); combined Figure 8 , is the principle diagram for terrain slope calculation. Among them, the inflection point Node i correspond Figure 8 The central pixel e in .

[0160] Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the x direction dz / dx:

[0161] dz / dx=((El(c)+2El(f)+El(I))-(El(a)+2El(d)+El(g))) / (8×x_cellsize)

[0162] Among them: x_cellsize represents the size of each pixel in the x direction;

[0163] Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the y direction dz / dy:

[0164] dz / dy=((El(g)+2El(h)+El(I))-(El(a)+2El(b)+El(c))) / (8×y_cellsize)

[0165] Among them: y_cellsize represents the size of each pixel in the y direction;

[0166] Step S8.4, use the following formula to get the inflection point Nodei Slope i :

[0167]

[0168] So far, we get the inflection point Node i Slope i .

[0169] like Fig. 9 As shown in Table 4, the calculation results of the inflection point slope are as follows:

[0170] Table 4: Example of obtaining the inflection point slope

[0171] PnameId POINT_X POINT_Y Slope Node1 2525.917 3967.514 48.625 Node2 2519.068 3960.024 9.666 Node3 2512.625 3962.455 8.655 Node4 2508.299 3964.370 7.138 Node5 2504.188 3966.415 19.606 Node6 2496.933 3970.459 12.484 Node7 2493.220 3972.812 5.609 Node8 2491.582 3973.915 5.609 Node9 2511.467 3982.016 25.477

[0172] Step S9, for the inflection point Node i The angle α i , land use classification and terrain slope i Conduct a comprehensive assessment to evaluate the inflection point Node i Is it suitable as the boundary point of the hydropower project safety management scope? At the same time, analyze the inflection point Node i Whether the location can be used to set up boundary points and stakes;

[0173] In this example, after analyzing the calculation results of the redline inflection point angle, the inflection points with angles between 30 degrees and 165 degrees were selected, and it was considered that their direction changes were large; furthermore, after analyzing the classification data of the land use status of the redline inflection points, it was considered that agricultural land was prone to damage the boundary point mark during use, so the redline inflection point at the agricultural land location was set as the boundary point; because the construction process will have a relatively large impact on the terrain slope, the original terrain slope is currently calculated and is only used to consider whether the redline inflection point is suitable for setting the boundary point mark. Finally, the boundary point and its mark position need to be verified again during the implementation stage. The example redline boundary point setting is shown in Table 5.

[0174] Table 5: Results of setting red line boundary points in comprehensive analysis example

[0175] PnameId POINT_X POINT_Y α TDLYXZFL Slope Node1 2525.917 3967.514 92.66 Arbor woodland 48.625 Node2 2519.068 3960.024 111.77 River water surface 9.666 Node3 2512.625 3962.455 176.79 River water surface 8.655 Node4 2508.299 3964.370 177.43 Arbor woodland 7.138 Node5 2504.188 3966.415 177.31 River water surface 19.606 Node6 2496.933 3970.459 176.77 Arbor woodland 12.484 Node7 2493.220 3972.812 178.40 River water surface 5.609 Node8 2491.582 3973.915 56.13 River water surface 5.609 Node9 2511.467 3982.016 112.73 Arbor woodland 25.477

[0176] In summary, Node1, Node2, Node8, and Node9 are selected as the boundary points. Node1 needs to verify whether the boundary point markers can be buried during the implementation phase.

[0177] Step S10, executing steps S5 to S9 for n inflection points, obtaining multiple boundary points on each land acquisition red line polygonal contour, connecting the multiple boundary points to form a closed area, which is the safety management scope of the hydropower project.

[0178] The turning point angle, land use classification and terrain slope of each record are calculated cyclically, and the location of the boundary points is comprehensively analyzed to finally determine the safety management scope of the hydropower project. The permanent land acquisition red line of the hydropower project includes the land acquisition red line of the narrow road. Since the number of turning point angles is relatively large within the setting rules, this method can be used as a reference when setting the actual boundary points to optimize the boundary point setting.

[0179] like Figure 10 to Figure 14 As shown, they are respectively the boundary point setting results of example data 1, the boundary point setting results of example data 2, the boundary point setting results of example data 3, the boundary point setting results of example data 4, and the boundary point setting results of example data 5.

[0180] The present invention belongs to the application field of the technical method for setting the position of the boundary point of the safety management scope of the hydropower project. It mainly adopts the spatial data processing and analysis technology based on the scope of the project land acquisition red line, extracts the permanent land acquisition red line scope by inputting the land acquisition red line vector data, calculates the angle formed by the permanent land acquisition red line turning point and the two connected line segments, sets the boundary point setting rules, comprehensively considers the land use status classification and terrain slope of the boundary point, and can quickly set the boundary point of the safety management scope. The method can automatically and quickly set the position of the boundary point of the safety management scope of the hydropower project and its related application analysis.

[0181] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be considered as the scope of protection of the present invention.

Claims

1. A method for setting the safety management scope of a hydropower project, characterized in that: The following steps are involved: Step S1, inputting the hydropower project land acquisition red line polygon vector data; each land acquisition red line polygon has a land acquisition type attribute; the land acquisition type attribute includes two types: permanent land use and temporary land use; Step S2, traversing the input land acquisition red line polygon vector data, extracting the land acquisition red line polygon vector data of permanent land acquisition type; Step S3, for each extracted land acquisition red line polygon vector data of permanent land acquisition type, executing steps S4 to S10; Step S4, traverse the surface elements formed by the land acquisition red line polygon vector data, obtain the land acquisition red line polygon contour line, extract the inflection point data on the land acquisition red line polygon contour line, and obtain the position coordinates of each inflection point, and number the inflection points in an incremental manner, Node i Indicates the number of the i-th inflection point, i = 1, 2, ..., n, n is the total number of inflection points on the polygonal contour line of the land acquisition red line, inflection point Node i The coordinates are recorded as (x i ,y i ); Step S5: Analyze and obtain the inflection point Node i The two line segments connected to the polygonal contour line of the land acquisition red line, and the line segments on each line segment connected to the inflection point Node i Non-overlapping inflection points j Node k , where j = 1, 2, ..., n, k = 1, 2, ..., n, and i ≠ j ≠ k; Step S6, inflection point Node i and inflection point Node j The connected line segment is L ij , inflection point Node i and inflection point Node k The connected line segment is L ik , calculate the line segment L ij and line segment L ik At the inflection point i The angle α of the position i ; Step S7, analyze and obtain the inflection point Node i Classification of land use status; Step S7 is specifically as follows: Step S7.1, input the land use status classification data of the land acquisition scope of the hydropower project; use the following formula to obtain the half of the square root of the minimum plot area Min_MJ as the grid cell size Cell_Size, and perform grid processing on the land use status classification data; Step S7.2, for each grid, take the land use status classification unique identification code BSM as the grid unit value, use the scan line seed point filling algorithm to realize the rasterization of vector data, obtain the land use status classification unique identification code BSM of each grid, and obtain the first layer in which each grid has the land use status classification unique identification code BSM; Step S7.3, for the inflection point Node i The coordinates (x i ,y i ) and the angle α i The second layer uses the same grid cell size Cell_Size for rasterization, and the following formula is used to obtain each inflection point Node i The row number of the grid cell H i and column number L i : Where: (x0, y0) represents the coordinates of the lower left corner of the first layer; Step S7.4, performing position overlap analysis on the first layer obtained in step S7.2 and the second layer obtained in step S7.3, and obtaining each inflection point Node i The unique identification code of land use classification BSM can be obtained for each inflection point Node i Land use status classification; Step S8: Analyze and obtain the inflection point Node i Slope i ; Step S9, for the inflection point Node i The angle α i , land use classification and terrain slope i Conduct a comprehensive assessment to evaluate the inflection point Node i Is it suitable as the boundary point of the hydropower project safety management scope? At the same time, analyze the inflection point Node i Whether the location can be used to set up boundary points and stakes; Step S10, executing steps S5 to S9 for n inflection points, obtaining multiple boundary points on each land acquisition red line polygonal contour, connecting the multiple boundary points to form a closed area, which is the safety management scope of the hydropower project.

2. A method for setting the scope of safety management of a hydropower project according to claim 1, characterized in that: Step S5 is specifically as follows: Step S5.1, interrupt the polygonal contour line of the land acquisition red line at each turning point, thereby obtaining multiple line segments; number each line segment in an incremental manner, Line w represents the number of the w-th line segment, w = 1, 2, ..., W, W is the total number of line segments; Step S5.2, spatially connecting the line segments and the inflection points to obtain two inflection points connected to each line segment, thereby obtaining a spatial positional relationship between the line segments and the inflection points, and further obtaining a line segment association result; Step S5.3, spatially connect the inflection point with the line segment association result of step S5.2 to obtain a set of inflection points on each inflection point and the line segment connected to it; Step S5.4, traverse each inflection point Node i , get each inflection point Node i All other inflection point data connected to it are deduplicated from all other inflection point data, and the remaining two inflection point data are the inflection point Node i The inflection point at the other end of two adjacent line segments is the inflection point Node j and inflection point Node k .

3. A method for setting the scope of safety management of a hydropower project according to claim 1, characterized in that: Step S6 is specifically as follows: Step S6.1, inflection point Node i The position coordinates are (x i ,y i );Inflection pointNode j The position coordinates are (x j ,y j );Inflection pointNode k The position coordinates are (x k ,y k ); Step S6.2, use formula 1 to get the inflection point Node i To the turning point Node j A vector, that is: vector Node i Node j : VectorNode i Node j =(x j -x i ,y j -y i ) Formula 1 uses Formula 2 to get the inflection point Node i To the turning point Node k A vector, that is: vector Node i Node k : VectorNode i Node k =(x k -x i ,y k -y i ) Formula 2 Using formula 3, we get the vector Node i Node j and vectorNode i Node k The product of: VectorNode i Node j Vector Node i Node k =(x j -x i )×(x k -x i )+(y j -y i )×(y k -y i )Formula 3 Using formula 4, we can get the inflection point Node i To the turning point Node j Distance|Node i Node j |, which is the line segment L ij Length: Using formula 5, we get the inflection point Node i To the turning point Node k Distance|Node i Node k |, which is the line segment L ik Length: Using formula 6, we get line segment L ij and line segment L ik At the inflection point i The angle N in radians of the position i : N i = arccos(direction Node i Node j ·Direction Node i Node k ) / (|Node i Node j |×|Node i Node k |) Formula 6 Using formula 7, we get line segment L ij and line segment L ik At the inflection point i The angle α of the position i , where the angle α i The unit of is degrees: α i =(180.0×N i ) / PI Formula 7 Among them: PI is π.

4. A method for setting the scope of safety management of a hydropower project according to claim 1, characterized in that: Step S8 is specifically as follows: Step S8.1, input DEM data; Step S8.2, for the inflection point Node i , obtain the elevation of each pixel in its eight neighborhoods, namely: the elevation of the upper left pixel a is El(a), the elevation of the upper pixel b is El(b), the elevation of the upper right pixel c is El(c), the elevation of the left pixel d is El(d), the elevation of the right pixel f is El(f), the elevation of the lower left pixel g is El(g), the elevation of the lower pixel h is El(h), and the elevation of the lower right pixel I is El(I); Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the x direction dz / dx: dz / dx=((El(c)+2El(f)+El(I))-(El(a)+2El(d)+El(g))) / (8×x_cellsize) Among them: x_cellsize represents the size of each pixel in the x direction; Step S8.3, use the following formula to get the inflection point Node i The rate of change of elevation in the y direction dz / dy: dz / dy=((El(g)+2El(h)+El(I))-(El(a)+2El(b)+El(c))) / (8×y_cellsize) Among them: y_cellsize represents the size of each pixel in the y direction; Step S8.4, use the following formula to get the inflection point Node i Slope i : So far, we get the inflection point Node i Slope i .

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