A site selection method for a water and electricity engineering security monitoring point

Abstract

The application discloses a kind of water and electricity engineering security monitoring point site location method, comprising: determining the management range of water and electricity engineering, corresponding topographic data and vector data are acquired;According to the boundary line of vector data acquisition management range, inflection point, cut point and management range is not covered contour line segment midpoint, determine candidate monitoring point site;According to candidate monitoring point site, build coverage evaluation model, and coverage evaluation model is used to generate optimal monitoring point site layout scheme from candidate monitoring point site;The constraint condition of coverage evaluation model is that security monitoring point site is on the boundary line of management range, the coverage range of security monitoring point site is video monitoring surveillance range, security monitoring point site distance is equivalent, the minimum overlap area of buffer zone range, the maximum range of security monitoring point site coverage range surface element;According to optimal monitoring point site layout scheme, management range and topographic data tuning, generate final monitoring point site layout scheme.According to the above technical scheme, the efficient site selection of water and electricity engineering security monitoring point site can be realized.

Description

Technical Field

[0001] This invention relates to the field of spatial data processing and analysis, and more specifically, to a method for selecting the location of security monitoring points in hydropower projects. Background Technology

[0002] In the management of hydropower projects, it is necessary to implement the requirement of full security monitoring coverage within the project management scope and clarify management responsibilities. Currently, during the project design phase, the setting of security monitoring points along the outline of the management scope is based on a 200m monitoring range as the standard for video surveillance performance parameters. Preliminary calculations and deployments are made by dividing the management scope length by 200m and rounding up, without considering actual conditions such as terrain undulations causing visual obstruction, outline shape, and subsequent installation conditions. After the project is completed, the monitoring points will be determined based on on-site surveys. Monitoring site selection methods can be divided into on-site selection and computer-aided selection. Computer-aided selection refers to manual selection based on geographic information data that reflects the environmental characteristics of the target area, such as road network data and digital elevation models (DEMs), through human-computer interaction, or by establishing a mathematical model of the monitoring site selection problem and using GIS analysis technology and intelligent optimization algorithms to solve the problem and obtain the optimal site selection and coverage optimization scheme. Traditional on-site selection methods rely on personnel experience; insufficient understanding of the overall coverage of the area and the complexity of the monitoring area increase the difficulty of on-site selection. Therefore, in practice, a combination of computer-aided and on-site surveys is adopted.

[0003] In recent years, with the rapid development of technologies such as photogrammetry, point cloud, and 3D modeling, it has become possible to obtain large-scale, high-precision, and high-quality geographic information data and models in a more efficient manner. This is of great significance for computer-aided site selection, which relies on data accuracy and quality. For example, traffic roads can be represented using vector data, and the road network can be abstracted into a graph using network topology properties. Then, the attributes of the traffic network, traffic conditions, population distribution, and road intersections can be analyzed to establish a perception probability optimization model. Finally, a permutation iterative algorithm based on the contribution of intersections can be designed to solve the model. Another example is transforming the site selection problem into a multi-objective optimization problem and using particle swarm optimization to solve it. By constructing problem models under different monitoring scenarios and different optimization objectives, the effectiveness of the optimization algorithm can be verified. Based on the solution results, the nodes of the monitoring network can be arranged and the camera orientation optimized to enhance the coverage quality of the monitoring network and save on the construction cost of the monitoring network, ultimately achieving the optimization of campus monitoring site selection. These solutions all use relatively complex models for academic research, with a high learning threshold and high requirements for users; moreover, they do not consider complex environments such as undulating terrain.

[0004] Therefore, there is an urgent need for a technical solution that, for hydropower project management scenarios, takes the management scope of the hydropower project as a benchmark and comprehensively considers multiple factors such as security monitoring performance parameters, management scope outline characteristics, and undulating terrain to achieve the site selection of security monitoring points for hydropower projects. Summary of the Invention

[0005] To achieve the above objectives, this application provides a method for selecting the location of security monitoring points in hydropower projects, comprising the following steps: Determine the management scope of the hydropower project and obtain the corresponding topographic data and vector data; among which, the vector data is used to reflect the boundary and shape information of the management scope. Based on vector data, the boundary line, inflection points, tangent points, and midpoints of the outline segments not covered by the management area are obtained to determine candidate monitoring points; among them, the tangent point is the point of tangency between the smallest bounding rectangle of the management area boundary line and the management area boundary line. A coverage evaluation model is constructed based on the candidate monitoring points. The coverage evaluation model is used to generate the optimal monitoring point layout scheme from the candidate monitoring points. The constraints of the coverage evaluation model are that the security monitoring points are on the boundary line of the management area, the coverage area of ​​the security monitoring points is the video surveillance range, the security monitoring points are relatively close together, the overlap area of ​​the buffer zone is minimized, and the coverage area of ​​the security monitoring points is maximized. The final monitoring point layout plan is generated by optimizing the optimal monitoring point layout scheme, management scope, and terrain data.

[0006] The process of determining candidate monitoring points includes the following steps: Determine the minimum bounding rectangle of the management area boundary; The first candidate site selection point is determined as the point where the boundary line of the management area is tangent to the smallest bounding rectangle; Based on the video surveillance monitoring range, and combined with the first candidate site selection point and supplemented with inflection points, a second candidate site selection point is generated; Based on the second candidate site selection point, supplementary candidate sites are generated to form a third candidate site selection point, thus forming a pre-selected security monitoring point.

[0007] The process of determining the minimum bounding rectangle of the management area boundary includes the following steps: The coordinates of the midpoint of the management area are: ( , ),in, ... , ... The coordinates of N inflection points on the boundary line of the management area are given by ( ). ), ( ), ..., ( ); The inflection point on the boundary line of the management area is circled around the midpoint ( Rotate counterclockwise by angle A; Based on the coordinate set of the rotated coordinate points, the coordinates of the four corner points of the circumscribed rectangle are defined as follows: ( ), ( ), ( ), ( Record the coordinates of the corner points and the rotation angle of the circumscribed rectangle, and calculate the area of ​​the circumscribed rectangle; Repeat the rotation N times, where the total angle A of the N rotations does not exceed 90 degrees. Calculate the area of ​​the bounding rectangle after each rotation. Compare the areas of the bounding rectangles after N rotations to determine the minimum bounding rectangle; The boundary line of the management range corresponding to the minimum bounding rectangle is restored to its original position, and the bounding rectangle is determined based on the coordinates of the four corner points of the minimum bounding rectangle.

[0008] The methods for determining the first candidate site include: Let there be three points A on the plane. B () ), C ( Points A and B are the endpoints of any side of the minimum bounding rectangle, and point C is the inflection point. Determine the relationship between point C and vector. The positional relationship is represented as: , If S(A,B,C) is greater than 0, then C is to the left of vector AB; if S(A,B,C) is less than 0, then C is to the right of vector AB; if S(A,B,C) is equal to 0, then C is on line AB. If point C lies on line AB, then point C is the first candidate location point.

[0009] Furthermore, generating a second candidate site includes the following steps: Calculate the buffer range of the first candidate address point; Calculate the inflection point angle, extract important inflection points based on the inflection point angle, eliminate important inflection points within the buffer zone, and retain important inflection points and the first candidate site selection point to form the second candidate site selection point.

[0010] When extracting important inflection points based on the angle between inflection points: a threshold angle is set. When the angle between the inflection points is greater than the threshold angle, the direction of the inflection point changes significantly, and the inflection point is considered an important inflection point.

[0011] Furthermore, supplementary candidate points based on the second candidate site selection point include: Obtain the n inflection points of the boundary line of the management area, which are: ( ), ( ), ( ...、( ); Sequentially determine whether the adjacent inflection points of the n inflection points are within the buffer of the second candidate location point. If two adjacent inflection points are not in the same buffer, only one is in the buffer, or neither is in the buffer, record the segment identifier code formed by the inflection point and the adjacent inflection points, and calculate the intersection point of the segment with the buffer. The intersection point of the segment with the buffer is realized by solving the equation of the circle and the equation of the line. Supplementary candidate points are determined based on the intersections of the line segment and the buffer zone.

[0012] The steps for determining supplementary candidate points based on the intersection of the line segment and the buffer zone include: Obtain the intersection point A of the line segment and the buffer. Inflection point B, which is not in the buffer zone and is adjacent to the intersection point ( ); Define line segment AB as the uncovered contour line segment, and calculate the length of each uncovered contour line segment. , represented as: ; if ≤2×D, where D is the buffer radius, divide the uncovered contour line segment into two segments, and extract the midpoint ( As a supplementary candidate point, it is represented as: , ; if Given a length >2×D, determine the midpoint of the uncovered contour segment AB. Divide the uncovered contour segment into two segments using this midpoint. Determine if the length of each uncovered contour segment is ≤2×D. If not, continue to obtain midpoints and use these midpoints to further divide the segment into uncovered contour segments until the length of each uncovered contour segment is ≤2×D. Then, obtain the midpoint (…). () as supplementary candidate points.

[0013] Furthermore, the overall objective function of the coverage evaluation model is: ,in, For the spacing between dots, To minimize the weight of overlap, Coverage maximizes weight. Optimize the objective function for the pixel spacing. The objective is to minimize buffer overlap. To maximize the objective by overlapping with the polygon, the weight constraints are expressed as: ; in, ,in, It represents the target's equidistant distance, where L is the perimeter of the polygon, and |*| represents the Euclidean distance; ,in, Let P represent the buffer zone of point P, and A(x) represent the area function. ,in, Represents surface elements.

[0014] Furthermore, generating the final monitoring point layout scheme includes: Obtain the optimal layout of monitoring points and terrain data; By using field-of-view analysis and considering the occlusion effect of terrain on the line of sight, the line of sight range of the monitoring equipment is simulated, and the presence of line-of-view obstruction is checked at each point. For locations where the line of sight is obstructed, adjustments are made or new locations are selected to generate the final monitoring point layout plan. A visual site selection analysis report and layout diagram are generated based on the final monitoring point layout scheme.

[0015] This invention utilizes spatial data processing and analysis technology to deeply integrate the actual needs of security monitoring point selection within the management scope of hydropower projects. Based on the management scope of the hydropower project, it comprehensively considers multiple dimensions of factors, including security monitoring performance parameters, the outline characteristics of the management scope, and the obstruction effect of terrain on the line of sight. This effectively solves problems such as traditional site selection methods neglecting terrain, outline, and installation conditions; reliance on experience and insufficient overall understanding in on-site site selection; and the impact of data accuracy and quality on computer-aided site selection. It achieves automated, intelligent, and precise site selection for security monitoring points within the management scope of hydropower projects, lowering the user's operational threshold, improving site selection efficiency and accuracy, and providing a solid and reliable technical guarantee for the safe operation and management of hydropower projects. Attached Figure Description

[0016] Figure 1 This is a step diagram of the method for selecting the location of security monitoring points in hydropower projects according to an embodiment of the present invention; Figure 2 This is a flowchart illustrating the process of determining candidate monitoring points during the site selection process according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the location selection process provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a hydropower project security monitoring point location selection system provided in an embodiment of the present invention. Detailed Implementation

[0017] The method for selecting security monitoring points in hydropower projects provided by this invention takes the management scope of the hydropower project as a benchmark. Under the premise that the monitoring range of the security monitoring points fully covers the management scope, it uses spatial data processing and analysis technology to obtain the smallest bounding rectangle of the management scope based on the vector data of the management scope. Then, it obtains candidate points based on the inflection points of the management scope, the angle between two adjacent line segments, and the uncovered line segments on the boundary line of the management scope. Furthermore, it considers the influence of terrain on the line of sight, improves the selection of security monitoring points, and quickly realizes the selection of security monitoring points on the boundary line of the management scope.

[0018] The specific implementation of the present invention will now be described in detail with reference to the accompanying drawings.

[0019] The implementation steps of the hydropower project security monitoring point selection method provided by this invention are as follows: Figure 1 As shown, it includes the following steps: Step S100: Determine the management scope of the hydropower project and obtain the corresponding topographic data and vector data. The vector data is obtained based on the project land acquisition boundary line and can accurately reflect the boundary and shape information of the management scope. The topographic data can be obtained through a digital elevation model (DEM).

[0020] This invention provides a specific embodiment where the terrain data within the management area of ​​the hydropower project is TIF format vector data, comprising 353 rows and 252 columns. As shown in part (a) of Figure 3, the background portion is the terrain data.

[0021] Step S110: Based on the vector data, obtain the inflection point of the management range, the tangent point of the boundary line of the management range, and the midpoint of the outline segment of the management range not covered, and determine the candidate monitoring point location; In this step, the vector data corresponding to the management area is traversed row by row to obtain the boundary line of the management area and the inflection points on the line. As shown in part (a) of Figure 3, the black line represents the boundary line of the management area. Key points and key angles are calculated and determined along the boundary line of the management area to filter candidate monitoring points. Specific processing steps are as follows... Figure 2 As shown, it includes the following steps: Step S111: Determine the minimum circumscribed rectangle of the management area boundary line using the rotating caliper method; In this step, vector data is processed using a rotating coordinate system: by continuously rotating the coordinate system, the inflection points, rotation angles, and areas of each bounding rectangle are calculated; the calculated areas of multiple bounding rectangles are compared and analyzed, and the bounding rectangle with the smallest area is selected; then, through a reverse coordinate rotation operation, the bounding rectangle with the smallest area is restored to the original graphic coordinate system, thus obtaining the smallest bounding rectangle of the original graphic and the inflection points tangent to that rectangle. The determination steps are as follows: 1) First, determine the coordinates of the midpoint of the management area as follows: ( , ),in, ... , ... The coordinates of N inflection points on the boundary line of the management area are given by ( ). ), ( ), ..., ( ); 2) Determine the circumscribed rectangle based on the rotation angle A, specifically: The inflection point on the boundary line of the management scope ( ) around the midpoint ( Rotate counterclockwise by angle A, and the coordinate point of the inflection point after rotation is ( ),and: Based on the coordinate set of the rotated coordinate points, define the coordinates of the four corner points of the circumscribed rectangle. The coordinates of the four corner points of the circumscribed rectangle are as follows: ( ), ( ), ( ), ( Simultaneously, record the coordinates of the corner points and the rotation angle of the circumscribed rectangle, and calculate the area of ​​the circumscribed rectangle; 3) Based on the boundary line of the management area after rotation, determine the circumscribed rectangle again according to the rotation angle A; repeat the rotation N times, and the total rotation angle A of N times shall not exceed 90 degrees; record the coordinates of the four corner points and the rotation angle of the circumscribed rectangle for each rotation, and calculate the area of ​​the circumscribed rectangle after each rotation. 4) Compare the areas of the circumscribed rectangles after N rotations to determine the minimum circumscribed rectangle; 5) Based on the total rotation angle of the management range boundary lines when the minimum bounding rectangle is obtained, rotate the corresponding management range boundary lines in the opposite direction around the midpoint to restore them to their original positions. Determine the bounding rectangle based on the coordinates of the four corner points of the minimum bounding rectangle, such as... Figure 3 As shown in part (b).

[0022] Step S112: Determine the first candidate site selection point as the point where the boundary line of the management area is tangent to the minimum bounding rectangle; Given the coordinates of the corner points of the circumscribed rectangle and the coordinates of the inflection points of the management area, the inflection points on the sides of the circumscribed rectangle, i.e., the points where the boundary line of the management area is tangent to the smallest circumscribed rectangle, are determined as follows: 1) Let there be three points A ( ) on the plane. B () ), C ( Points A and B are the endpoints of any side of the smallest bounding rectangle, and point C is the inflection point; 2) Determine the relationship between point C and vector. The positional relationship is represented as: , If S(A,B,C) is greater than 0, then C is to the left of vector AB; if S(A,B,C) is less than 0, then C is to the right of vector AB; if S(A,B,C) is equal to 0, then C is on line AB.

[0023] Based on video surveillance performance parameters, such as the effective monitoring radius, buffer analysis is performed on inflection points tangent to the minimum bounding rectangle. A buffer is generated centered on each inflection point according to the effective radius of the video surveillance, used to initially determine the coverage area of ​​the monitoring point. Therefore, points where the management range boundary line is tangent to the minimum bounding rectangle are selected as the first candidate site selection points.

[0024] The first candidate site obtained through this step is as follows: Figure 3 As shown in part (c).

[0025] Step S113: Based on the video surveillance monitoring range and combined with the first candidate location point to supplement the inflection point, generate the second candidate location point. The specific implementation steps include: 1) Calculate the buffer zone of the first candidate site selection point: Use the video surveillance monitoring range as the buffer radius D (e.g., the video surveillance monitoring range is 200m), and the first candidate site selection point as the center of the buffer zone. Assume the coordinates of the inflection point are ( Then the buffer range of the first candidate address point is as follows: Figure 3 As shown in section (d); the monitoring range of the video surveillance is expressed by the formula: + ≤40000; 2) Calculate the angle between the line segments on both sides of the turning point of the management area, i.e. the turning point angle. Extract important turning points based on the turning point angle, and form a second candidate site selection point with the first candidate site selection point. First, calculate the angle between each inflection point on the boundary line of the management area: Given three inflection points A (… B () ), C ( The angle between inflection point A is calculated using vector calculation methods, and the calculation process is shown below: Where β is in radians, α is in degrees, and PI is π.

[0026] Extract inflection points at specified angles to form important inflection points, such as... Figure 3As shown in section (e), in this invention, inflection points with significant directional changes are extracted as important inflection points. Specifically, an angle threshold is set; when the angle between an inflection point is greater than the threshold, the inflection point is considered to have a significant directional change and can be considered an important inflection point. To avoid important inflection points being on a single line or having excessively small angles, the angle threshold is typically set within the range of [30°, 165°].

[0027] like Figure 3 As shown in section (f), since important inflection points may be within the buffer zone, important inflection points within the buffer zone are removed, and the remaining important inflection points, together with the first candidate location point, constitute the second candidate location point. At this time, the second candidate location point is as follows: Figure 3 As shown in section (g), the important inflection points retained in this processing are the red inflection points in the figure.

[0028] Step S114: Supplement candidate points and generate a third candidate site point based on the second candidate site point; like Figure 3 As shown in section (g), some line segments on the boundary of the management area are not covered by the buffer zone. These uncovered segments may be weak areas in the monitoring coverage, requiring further monitoring point setup. In this step, candidate points are added for these segments, as detailed below: 1) Obtain the n inflection points of the boundary line of the management area, which are: ( ), ( ), ( ...、( ); 2) Sequentially determine whether the adjacent inflection points of the n inflection points are within the buffers of the second candidate location points. If two adjacent inflection points are in the same buffer, the line segment is covered by the buffer and no processing is required. Otherwise, if two adjacent inflection points are not in the same buffer, only one is in the buffer, or neither is in the buffer, the line segment identifier code formed by the inflection point and the adjacent inflection points needs to be recorded, and the intersection of the line segment and the buffer needs to be calculated. The intersection point (x, y) of the line segment and the buffer zone is determined by solving a system of equations for the line and the circle; the equation of the circle is: + ≤40000, the equation of the line is: .

[0029] At this point, after obtaining the coordinates of the intersection points between the line segments and the buffer zone, the uncovered contour line segments are formed by connecting the line segments between multiple intersection points. Figure 3 As shown in the (h) part.

[0030] 3) Determine supplementary candidate points based on the intersections of the line segment and the buffer zone; Specifically, obtain the intersection point A of the line segment and the buffer. Inflection point B, which is not in the buffer zone and is adjacent to the intersection point ( Define line segment AB as the uncovered contour line segment, and calculate the length of each uncovered contour line segment. , represented as: ; if ≤2×D, where D is the buffer radius (e.g., 200m), divide the uncovered contour line segment into two segments and extract the midpoint ( As a supplementary candidate point, it is represented as: , .

[0031] if Given a length >2×D, determine the midpoint of the uncovered contour segment AB. Divide the uncovered contour segment into two segments using the midpoint. Determine if the length of each uncovered contour segment is ≤2×D. If not, continue to find the midpoint and use it to further divide the segment into uncovered contour segments until the length of each uncovered contour segment is ≤2×D. Then, find the midpoint again. () as supplementary candidate points.

[0032] Supplementary candidate points such as Figure 3 The black dots in part (i) are shown.

[0033] At this point, the supplementary candidate point is merged with the second candidate point to form a third candidate point, thus creating a pre-selected security monitoring point. Figure 3 As shown in part (j).

[0034] Step S120: Construct a coverage evaluation model based on the candidate monitoring points. The coverage evaluation model is used to generate the optimal monitoring point layout scheme from the candidate monitoring points. like Figure 3 As shown in part (j), some of the pre-selected security monitoring points are too close together, leading to overlapping coverage and wasted resources. Therefore, a more reasonable monitoring point layout scheme is generated by using the constraints of the coverage evaluation model.

[0035] Specifically, the monitoring point layout plan involves selecting a certain number of points from the candidate monitoring points.

[0036] In the process of obtaining the optimal monitoring point layout scheme, the coverage evaluation model continuously optimizes the monitoring point layout through local optimization until the monitoring point layout can no longer be significantly optimized; through global optimization, the scheme with the largest coverage efficiency index is selected from the final set of preferred schemes as the globally optimal monitoring point layout scheme.

[0037] Specifically, the coverage assessment model is defined by the following constraints: the security monitoring points are located on the boundary line of the management area, the coverage area of ​​the security monitoring points is the video surveillance range D, the distance between video points is relatively equal, the overlap area of ​​the buffer zone is minimized, and the coverage area of ​​the security monitoring points is maximized.

[0038] The overall objective function is defined as follows: ,in, For the spacing between dots, To minimize the weight of overlap, Coverage maximizes weight. Optimize the objective function for the pixel spacing. The objective is to minimize buffer overlap. Maximize the target by overlapping with the polygon; The weight limit is represented as: , ,in, It represents the target's equidistant distance, where L is the perimeter of the polygon, and |*| represents the Euclidean distance; ,in, Let P represent the buffer zone of point P, and A(x) represent the area function.

[0039] ,in, Represents surface elements.

[0040] At this point, a monitoring point layout scheme can be generated, such as... Figure 3 The (k) part is shown.

[0041] Step S130: Optimize the monitoring point layout scheme based on the optimal monitoring point layout scheme, management scope and terrain data to generate the final monitoring point layout scheme.

[0042] In this step, terrain data is overlaid on the monitoring point layout plan to conduct viewpoint analysis, determine which areas within the coverage area are obstructed by the terrain, and whether removal is necessary during later construction, ultimately refining the site selection for security monitoring points. Specifically, this includes the following steps: 1) Data integration: Combine the optimal monitoring point layout scheme based on the coverage optimization goal (including: final point, buffer zone, management area) and terrain data to prepare for field of view analysis; 2) Conduct a field of view analysis: Using field of view analysis technology, consider the obstruction effect of terrain on the line of sight, simulate the line of sight range of the monitoring equipment, and check whether each point can cover the key areas within the management range without obstruction. 3) Location adjustment and optimization: For locations with obstructed views, adjust or reselect suitable locations based on the analysis results to generate the final monitoring point layout plan, ensuring that the monitoring points can effectively cover the management area; 4) Integration with other modules: Outputs the final monitoring point layout plan, and generates a visual site selection analysis report and layout diagram to provide users with an intuitive display.

[0043] like Figure 3 As shown in part (l), the red line in the figure represents the upper reservoir of a pumped storage power station in the design. The red dots represent the optimized video point locations, and the green area represents the visible range of the monitoring points in the design phase. The reservoir within the design red line needs to be excavated and expanded to form a reservoir basin in the later stage. It has been verified that the formation of the reservoir basin will not obstruct the video monitoring range, and can realize all-round monitoring without blind spots in the management scope of hydropower projects.

[0044] On the other hand, the present invention provides a site selection system for security monitoring points in hydropower projects, such as... Figure 4 As shown, it includes: The P400 data management module is used to determine the management scope of hydropower projects based on basic data and to obtain the corresponding topographic and vector data for that scope. Specifically, the data management module includes: 1) Data import unit, used to interact with management terminals and third-party systems, supports the import of geographic information data in various formats (such as vector data and raster data), including vector data of hydropower project management scope and digital elevation model (DEM) data; it also supports the input of video surveillance performance parameters (such as effective monitoring radius and viewing angle range).

[0045] 2) Data storage unit, used to store imported data, supports reasonable data structure for organization and management, so as to facilitate subsequent querying and analysis.

[0046] 3) Data editing unit, used to interact with user terminal and data storage unit; supports user terminal to edit imported data, such as modifying nodes and adjusting line segments of vector data within the management scope, to meet the data correction needs in practical applications; and transmits the edited data to data storage unit for storage.

[0047] The data export unit is used to respond to user terminal requests and export the processed data in a specific format to facilitate data interaction and sharing with other systems.

[0048] The connecting unit is used to provide basic data support for the subsequent calculation and analysis modules. During the operation of the calculation and data analysis modules, the modules need to read the required data from the data management module and store the processing results back to the database.

[0049] The P410 data analysis module is used to determine candidate monitoring points based on vector data. Specifically, the data analysis module includes: 1) Rectangular calculation unit, used to process vector data using the rotating caliper method, calculate the circumscribed rectangle with the smallest area, and determine its relative positional relationship with the original graphic.

[0050] 2) Point calculation unit, used to calculate inflection points based on the boundary line of the management range and the outer rectangle with the smallest area, and to calculate candidate monitoring points in combination with buffer analysis unit and line segment calculation unit.

[0051] The calculation of candidate monitoring points includes: calculating the included angle between the line segments on both sides of the inflection point on the boundary line of the management range; extracting important inflection points based on the set included angle threshold, with the selection of those with significant changes in direction as the basis; combining the buffers of each inflection point output by the buffer analysis unit to eliminate important inflection points with overlapping buffers; and supplementing inflection points by combining the center point of the line segment outside the buffer output by the line segment calculation unit to generate candidate monitoring points.

[0052] 3) The line segment calculation unit combines the point calculation unit and the buffer analysis unit to determine line segments outside the buffer based on the boundary line of the management range. When determining line segments outside the buffer, the buffer of important inflection points and tangent points of the circumscribed rectangle is superimposed and analyzed with the boundary line of the management range to filter out uncovered contour line segments not covered by the buffer, calculate the midpoint of the uncovered contour line segments, and provide it to the point calculation unit.

[0053] 4) Buffer analysis unit, used to generate buffers at inflection points on the boundary line of the management range according to the effective monitoring radius set in the video surveillance performance parameters. The buffers can reflect the coverage of the set monitoring points.

[0054] The P420 coverage assessment module is used to construct a coverage assessment model based on candidate monitoring points. This model generates the optimal monitoring point layout scheme from the candidate points. Specifically, the coverage assessment model aims to maximize the coverage area of ​​the monitoring points while minimizing overlapping coverage areas. A coverage efficiency index is defined to measure the merits of different layout schemes. After defining the coverage assessment model, a certain number of point combinations are randomly selected from the candidate monitoring points obtained from the data analysis module to form an initial set of layout schemes. The coverage efficiency index of each initial scheme is calculated using the coverage assessment model, and the schemes are sorted according to the index value to select a set of preferred schemes. Each scheme in the preferred scheme set is locally optimized by fine-tuning the point positions or replacing some points to generate a new scheme, and the coverage efficiency index of the new scheme is calculated. If the new scheme is better, it is replaced until the scheme can no longer be significantly optimized. The scheme with the highest coverage efficiency index from the locally optimized scheme set is selected as the globally optimal monitoring point layout scheme.

[0055] The coverage assessment module also includes a connection unit, which is used to pass the globally optimal monitoring point layout scheme to the monitoring point layout module and the visualization display module, and store the results in the database of the data management module.

[0056] The P430 monitoring point layout module is used to optimize the monitoring point layout, management area, and terrain data output by the coverage assessment module, generating the final monitoring point layout scheme. Specifically, the monitoring point layout module includes: 1) Data integration unit, used to load the final point location provided by the point layout optimization module based on the coverage optimization target, the buffer generated by the data management module, the management range and terrain data, to prepare for view analysis.

[0057] 2) The line-of-sight analysis unit is used to combine line-of-sight analysis technology, consider the occlusion effect of terrain on the line of sight, simulate the line of sight range of the monitoring equipment, and check whether each point can cover the key area within the management range without obstruction.

[0058] 3) The point adjustment unit is used to adjust or reselect suitable points where there is obstruction of sight, so as to ensure that the monitoring points can effectively cover the management area.

[0059] 4) Connection Unit: The final monitoring point layout results after field of view analysis and optimization are fed back to the data management module for storage. At the same time, a visual site selection analysis report and layout diagram are generated and provided to the visualization module to provide users with an intuitive display.

[0060] The P440 visualization module is used to retrieve final data from the database and perform operations such as map display, chart display, and report generation, providing users with intuitive site selection results display and interactive functions.

[0061] The present invention provides a method and system for selecting security monitoring points in hydropower projects. Using a map as a background, it displays information such as the management scope of the hydropower project, the layout of monitoring points, and buffer zones, distinguished by different colors and symbols, facilitating a clear understanding of the distribution of monitoring points for users. Through visualization technology, various statistical charts are generated based on the results of the selected security monitoring points, such as coverage efficiency index change curves and comparative bar charts of different schemes, helping users analyze the advantages and disadvantages of different point layout schemes. Detailed site selection analysis reports can also be generated according to user needs, including the basis and methods for site selection, problems encountered during the process and their solutions, and the final point layout scheme.

[0062] The above-disclosed embodiments are merely a few specific examples of the present invention. However, the present invention is not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A method for selecting the location of security monitoring points in hydropower projects, characterized in that, Includes the following steps: The management scope of the hydropower project is determined, and the corresponding topographic data and vector data are obtained; wherein, the vector data is used to reflect the boundary and shape information of the management scope; Based on the vector data, obtain the boundary line, inflection point, tangent point, and midpoint of the outline segment not covered by the management range, and determine the candidate monitoring points; wherein, the tangent point is the point of tangency between the minimum bounding rectangle of the management range boundary line and the management range boundary line; A coverage evaluation model is constructed based on the candidate monitoring points. The coverage evaluation model is used to generate the optimal monitoring point layout scheme from the candidate monitoring points. The constraints of the coverage evaluation model are that the security monitoring points are on the boundary line of the management range, the coverage range of the security monitoring points is the video surveillance range, the security monitoring points are relatively close together, the overlap area of ​​the buffer zone is minimized, and the range of surface elements of the coverage range of the security monitoring points is maximized. The final monitoring point layout plan is generated by optimizing the optimal monitoring point layout scheme, management scope, and terrain data.

2. The method for selecting locations for security monitoring points in hydropower projects according to claim 1, characterized in that, Determining candidate monitoring locations includes the following steps: Determine the minimum bounding rectangle of the management area boundary; The first candidate site selection point is determined as the point where the boundary line of the management area is tangent to the smallest bounding rectangle; Based on the video surveillance monitoring range, and combined with the first candidate site selection point and supplemented with inflection points, a second candidate site selection point is generated; Based on the second candidate site selection point, supplementary candidate sites are generated, and a third candidate site selection point is generated to form a pre-selected security monitoring point.

3. The method for selecting locations for security monitoring points in hydropower projects according to claim 2, characterized in that, Determining the minimum circumscribed rectangle of the management area boundary line includes the following steps: The coordinates of the midpoint of the management area are: ( , ),in, ... , ... The coordinates of N inflection points on the boundary line of the management area are given by ( ). ), ( ), ..., ( ); The inflection point on the boundary line of the management area is circled around the midpoint ( Rotate counterclockwise by angle A; Based on the coordinate set of the rotated coordinate points, the coordinates of the four corner points of the circumscribed rectangle are defined as follows: ( ), ( ), ( ), ( Record the coordinates of the corner points and the rotation angle of the circumscribed rectangle, and calculate the area of ​​the circumscribed rectangle; Repeat the rotation N times, where the total angle A of the N rotations does not exceed 90 degrees. Calculate the area of ​​the bounding rectangle after each rotation. Compare the areas of the bounding rectangles after N rotations to determine the minimum bounding rectangle; The boundary line of the management range corresponding to the minimum bounding rectangle is restored to its original position, and the bounding rectangle is determined based on the coordinates of the four corner points of the minimum bounding rectangle.

4. The method for selecting locations for security monitoring points in hydropower projects according to claim 2, characterized in that, The method for determining the first candidate site includes: Let there be three points A on the plane. B () ), C ( Points A and B are the endpoints of any side of the minimum bounding rectangle, and point C is the inflection point. Determine the relationship between point C and vector. The positional relationship is represented as: ， If S(A,B,C) is greater than 0, then C is to the left of vector AB; if S(A,B,C) is less than 0, then C is to the right of vector AB; if S(A,B,C) is equal to 0, then C is on line AB. If point C lies on line AB, then point C is the first candidate location point.

5. The method for selecting locations for security monitoring points in hydropower projects according to claim 2, characterized in that, The process of generating the second candidate site includes the following steps: Calculate the buffer range of the first candidate address point; Calculate the inflection point angle, extract important inflection points based on the inflection point angle, eliminate important inflection points within the buffer zone, and retain important inflection points and the first candidate site selection point to form the second candidate site selection point.

6. The method for selecting locations for security monitoring points in hydropower projects according to claim 5, characterized in that, When extracting important inflection points based on the included angle of the inflection point: a threshold angle is set. When the included angle of the inflection point is greater than the threshold angle, it is determined that the direction of the inflection point changes significantly, and the inflection point is an important inflection point.

7. The method for selecting locations for security monitoring points in hydropower projects according to claim 2, characterized in that, The supplementary candidate points based on the second candidate site selection point include: Obtain the n inflection points of the boundary line of the management area, which are: ( ), ( ), ( ...、( ); Sequentially determine whether the adjacent inflection points of the n inflection points are within the buffer of the second candidate location point. If two adjacent inflection points are not in the same buffer, only one is in the buffer, or neither is in the buffer, record the segment identifier code formed by the inflection point and the adjacent inflection points, and calculate the intersection point of the segment with the buffer. The intersection point of the segment with the buffer is realized by solving the equation of the circle and the equation of the line. Supplementary candidate points are determined based on the intersection of the line segment and the buffer zone.

8. The method for selecting locations for security monitoring points in hydropower projects according to claim 7, characterized in that, The step of determining supplementary candidate points based on the intersection of the line segment and the buffer zone includes: Obtain the intersection point A of the line segment and the buffer. Inflection point B, which is not in the buffer zone and is adjacent to the intersection point ( ); Define line segment AB as the uncovered contour line segment, and calculate the length of each uncovered contour line segment. , is represented as: ； if ≤2×D, where D is the buffer radius, divide the uncovered contour line segment into two segments, and extract the midpoint ( As a supplementary candidate point, it is represented as: , ; if Given a length >2×D, determine the midpoint of the uncovered contour segment AB. Divide the uncovered contour segment into two segments using this midpoint. Determine if the length of each uncovered contour segment is ≤2×D. If not, continue to obtain midpoints and use these midpoints to further divide the segment into uncovered contour segments until the length of each uncovered contour segment is ≤2×D. Then, obtain the midpoint (…). () as supplementary candidate points.

9. The method for selecting locations for security monitoring points in hydropower projects according to claim 1, characterized in that, The overall objective function of the coverage assessment model is: ,in, For the spacing between dots, To minimize the weight of overlap, Coverage maximizes weight. Optimize the objective function for the pixel spacing. The objective is to minimize buffer overlap. To maximize the objective by overlapping with the polygon, the weight constraints are expressed as follows: ; in, ,in, It represents the target equidistant distance, where L is the perimeter of the polygon, and |*| represents the Euclidean distance; ,in, Let P represent the buffer zone of point P, and A(x) represent the area function. ,in, Represents surface elements.

10. The method for selecting the location of security monitoring points in hydropower projects according to claim 1, characterized in that, The final monitoring point layout scheme includes: Obtain the optimal layout of monitoring points and terrain data; By using field-of-view analysis, considering the occlusion effect of terrain on the line of sight, the line of sight range of the monitoring equipment is simulated, and the presence of line-of-view obstruction is checked at each point. For locations where the line of sight is obstructed, adjustments are made or new locations are selected to generate the final monitoring point layout plan. A visual site selection analysis report and layout diagram are generated based on the final monitoring point layout scheme.

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