Boundary decomposition-based spatial management range four-to-quantization determination method and system

Abstract

The application discloses a boundary decomposition-based spatial management range four-adjacent-plot quantization judgment method and system, relates to the technical field of spatial data processing and management, and constructs a cross-format and multi-coordinate-system spatial management range batch automation processing method and system through spatial management range data reading and preprocessing, boundary decomposition and azimuth angle calculation, direction classification and adjacent object identification, attribute assignment and structured storage, and four-adjacent-plot comprehensive judgment, and outputs the result in a structured and unified coded form, so as to meet the efficient, accurate and standardized requirements of water conservancy management, land right confirmation, real estate registration and other businesses on four-adjacent-plot information.

Description

Technical Field

[0001] This invention relates to the field of spatial data processing and management technology, specifically to a method and system for quantitatively determining the boundaries of spatial management range based on boundary decomposition. Background Technology

[0002] In the water conservancy industry, the information on the boundaries of the management scope is one of the core spatial attributes. It describes the east, south, west, and north boundaries of the management boundary and the situation of adjacent objects. It is used to clarify the boundary location and adjacency relationship of rivers, reservoirs, canals, irrigation areas, etc. in the spatial database. It is an important basic data for ownership definition, spatial query and data exchange.

[0003] In current production practices, the extraction of boundary information for water conservancy management is still mainly done manually or through semi-automated processing. Operators manually identify adjacent management units or engineering facilities using GIS software such as CAD and ArcGIS by identifying boundary points and lines; they infer the directions of the management area based on the overall orientation or the location of the enclosing rectangle, and then manually fill in the boundary attribute table. This method is applicable when the data volume is small and the boundary shape is regular. However, in actual water conservancy operations, the river network is dense, the boundaries are complex, the adjacency relationships are diverse, and the amount of boundary data spanning administrative regions and management units is enormous. Existing methods are clearly insufficient in terms of efficiency, accuracy, and batch processing capabilities.

[0004] Existing commonly used algorithms rely on the overall geometric location of the management area, such as calculating the four adjacent objects of the circumscribed rectangle of the management area; or determining the four boundaries of adjacent objects by using the azimuth angle as a reference point, using the geometric center of the management area as a reference point. This overall orientation method is easily affected by local boundary morphology in water conservancy and other spatial boundary operations, leading to deviations in direction determination, especially in cases of meandering rivers, multi-segmented polylines in channels, complex reservoir shoreline curves, and irregular parcel boundaries. The adjacency relationship output is incomplete, especially when there are multiple adjacencies or discontinuous boundaries, which can easily lead to omissions, such as multiple management units adjacent to one side of a river or different land use types adjacent to one side of a parcel. It has poor adaptability to curves, multi-segmented polylines, and irregular boundaries, and cannot effectively handle complex boundaries caused by natural terrain or engineering structures. Batch processing relies on manual intervention, lacking fully automated and standardized output, making it difficult to meet the needs of rapid updating and sharing of river, lake, water conservancy project, and large-scale spatial boundary data. Similar problems also exist in other spatial boundary operations such as land registration, real estate registration, and cadastral management.

[0005] To address the problems of the existing technologies, our research team proposes a method and system for determining the spatial management range boundaries based on boundary decomposition. Summary of the Invention

[0006] To overcome the shortcomings of existing technologies, the purpose of this invention is to provide a method and system for determining the boundaries of spatial management range based on boundary decomposition. This method utilizes spatial data processing platforms such as FME (Feature Manipulation Engine) to automatically and standardizedly extract and structure the boundary information of multi-source spatial vector data, including rivers, reservoirs, pumping stations, canals, irrigation areas, water source protection areas, and land parcel boundaries, and supports batch processing across formats and coordinate systems.

[0007] This invention provides a method for determining the boundaries of a spatial management area based on boundary decomposition, comprising the following steps:

[0008] S10. Spatial management scope data reading and data preprocessing: Input multi-source spatial management scope data files, automatically identify the coordinate system type of the data, uniformly convert the coordinate system, perform topology checks, clean up redundancy, and correct boundary data by combining buffer preprocessing methods.

[0009] S20. Boundary decomposition and azimuth calculation: The closed boundary line is decomposed into the smallest indivisible boundary segment. The smallest boundary segment is a continuous boundary unit with boundary points at both ends and no other boundary points in the middle. The segments are filtered according to the length threshold, and then the azimuth of the filtered segments is calculated to obtain the azimuth data.

[0010] S30. Direction classification and adjacent object identification: Based on the acquired azimuth data, the line segment is divided into eight regional direction groups according to the preset azimuth threshold range. The spatial topology analysis method identifies the spatial objects on both sides of each line segment, extracts the identifiers of adjacent objects and records their side positions, and associates them with the direction classification results.

[0011] S40. Boundary segment boundary determination: Based on the partition direction of the segment and the lateral position of the adjacent object, the boundary attributes are assigned according to the preset determination rules.

[0012] S50. Structured attribute storage: The direction attribute, adjacent object identifier, determination method and four-boundary attribute of each boundary line segment are written into a structured attribute table with unified coding and stored according to unified coding and format standards, consistent with the coding rules of the water conservancy management system and land registration management system.

[0013] S60, Boundary Comprehensive Determination: For all boundary segments within the same management area, directional merging and deduplication are performed. For multiple segments in the same direction, they are grouped according to the adjacent object identifier. The cumulative adjacent length of the adjacent boundary is calculated as the priority sorting basis, and the identifier and corresponding area of ​​the adjacent object are recorded. Priority determination is performed according to business rules, and complete and unique boundary information is output.

[0014] S70. Output and system interface: Perform the above processing steps in batches across formats and coordinate systems, generate standard GIS data files or write them to the database, and interface with the water conservancy management system and land registration management system.

[0015] Further, step S10, spatial management scope data reading and preprocessing, specifically involves inputting a multi-source spatial management scope data file. This multi-source spatial management scope data includes water conservancy management boundaries and land parcel boundaries, and is not limited to various formats such as Shapefile, GeoDatabase, and CAD drawing files. Water conservancy management boundaries include rivers, reservoirs, pumping stations, canals, irrigation areas, and water source protection areas. The coordinate system type of the data is identified, such as geographic coordinate system or projected coordinate system. For data lacking coordinate system attributes, the coordinate system is manually specified. The input multi-source spatial management scope data undergoes format and coordinate system checks. Data from different sources is converted to a regionally unified projected coordinate system. Topological structure checks are performed, cleaning up redundant nodes, dangling lines, and duplicate points to ensure boundary closure and topological correctness. A buffer preprocessing method is used to correct boundary data, addressing minor gaps, coordinate accuracy deviations, or node misalignments, providing a stable and reliable spatial data foundation for subsequent boundary decomposition, adapting to complex situations such as river and lake shorelines, canal polylines, and irregular land parcel boundaries. The buffer preprocessing method includes:

[0016] (1) Use spatial analysis tools, such as the NeighborFinder module of the FME platform, to detect whether there are gaps between objects in the spatial management range and calculate the shortest distance between object boundaries; if the shortest distance is greater than zero and less than or equal to the preset gap threshold, mark the object pair and its gap location as gap areas to be repaired.

[0017] (2) Generate an outward buffer for the marked gap objects according to the set distance threshold, so that the objects that originally had gaps can contact each other or slightly overlap after buffering;

[0018] (3) Perform spatial intersection operation within the buffer range to extract the intersection area between the buffered objects. This area corresponds to the gap position between the original spatial management ranges. Optionally, calculate the area or minimum width of the intersection area and remove narrow face elements that are less than a preset threshold.

[0019] (4) Extract the centerline of the retained intersecting region using the Medial Axis or Skeletonization algorithm, and use the centerline as the initial geometry of the common boundary;

[0020] (5) Perform geometric optimization on the extracted centerline, including removing sharp corners, eliminating narrow necks, and smoothing curves, to improve the smoothness and spatial consistency of the common boundary;

[0021] (6) Optionally, compare the maximum offset between the optimized common boundary line and the original object boundary. If the offset exceeds the allowable error threshold, revert to the original boundary or submit for manual confirmation.

[0022] (7) Use the optimized common boundary line as the common boundary line of the adjusted two-space management scope, update the boundary data to eliminate topological errors caused by gaps, precision deviations or node misalignment, and ensure data continuity and consistency.

[0023] Further, step S20, boundary decomposition and azimuth calculation, specifically involves decomposing the closed boundary line into indivisible minimum boundary segments under a unified projection coordinate system, based on the spatial topology. Each minimum boundary segment is a continuous boundary unit with boundary points at both ends and no other boundary points in between, ensuring each segment has a clear start and end point. Segments are filtered according to a length threshold, retaining only those with a length not less than the set threshold, and eliminating short, unstable segments susceptible to local boundary jitter or reciprocating deformation, thus ensuring the stability and accuracy of the azimuth calculation. Subsequently, the azimuth of the filtered segments is calculated to generate high-precision, stable basic direction data. This step only generates azimuth information as the basis for subsequent direction classification and adjacency determination; it does not directly perform direction classification or boundary attribute identification. Under a unified projected coordinate system, closed boundaries are decomposed into indivisible minimum boundary segments based on spatial topology. These closed boundaries include river and lake shorelines, channel orientations, water conservancy project management boundaries, and land parcel boundaries, ensuring that each segment has a clear start and end point. A length threshold filtering mechanism is introduced to automatically eliminate short, unstable segments that are susceptible to local boundary jitter or deformation, ensuring the stability and accuracy of azimuth calculation from the source. The azimuth angle of the filtered segments is automatically calculated, generating high-precision and reliable geometric direction data, providing a stable and accurate foundation for subsequent direction classification and boundary determination, especially suitable for irregularly shaped or complex river and lake shorelines, channel boundaries, and land parcels. The azimuth angle calculation uses the great circle heading calculation formula in the geographic coordinate system, applicable to latitude and longitude data, such as cross-basin water conservancy projects or cross-regional land parcels. The angle calculation method between river shoreline segments and land parcel boundaries is based on the vector dot product angle calculation method to obtain the segment direction angle. Discrete direction encoding is used instead of continuous angle calculation in water conservancy project management and cadastral standardization scenarios.

[0024] Further, step S30, directional classification and adjacent object identification, specifically involves dividing the line segment into eight directional groups based on the acquired azimuth data and a preset, adjustable azimuth threshold. Using spatial topology analysis, spatial objects on both sides of each line segment are identified. One side represents the current management area, such as rivers, lakes, canals, and land parcels; the other side represents adjacent management areas or other spatial objects with clear boundaries, including but not limited to natural geographical elements, artificial facilities, special functional zones, and land use zones. Identifiers of adjacent objects, such as water conservancy project names and land parcel numbers, are extracted, and their location is recorded and associated with the directional classification results. Furthermore, when identifying spatial objects on both sides of each line segment using spatial topology analysis, if there are minor gaps or differences in data precision at the boundary, buffer adjacency analysis is used for supplementary judgment to ensure the integrity of the adjacency relationship. High-precision surveyed water conservancy projects and land parcel data use shared boundaries or nodes for topological relationship determination; adjacent river segments or adjacent land parcels use spatial indexing combined with distance thresholds to quickly match adjacent objects; the intersection relationship of adjacent management areas is directly calculated using polygon overlay analysis. A small gap refers to the shortest distance between the boundaries of two spatial objects being less than a certain set threshold. This threshold is usually set to a value that matches the data acquisition accuracy or coordinate unit, such as 0.01 meters to 1 meter, and is calculated as the equivalent projected distance in the geographic coordinate system.

[0025] In some embodiments, the line segment is divided into North, Northeast, East, Southeast, South, Southwest, West, and Northwest directional groups based on the acquired azimuth data, and the azimuth threshold is set as follows:

[0026] North region (330°, 360°] ∪ [0°, 30°);

[0027] Northeast region [30°, 60°];

[0028] Eastern zone (60°, 120°);

[0029] Southeast region [120°, 150°];

[0030] South zone (150°, 210°);

[0031] Southwest region [210°, 240°];

[0032] West zone (240°, 300°);

[0033] Northwest region [300°, 330°].

[0034] Based on stable azimuth data, and according to a preset and flexibly adjustable eight-directional classification threshold, line segments are divided into eight directional groups: North, Northeast, East, Southeast, South, Southwest, West, and Northwest. This forms a unified primary directional classification rule, which serves as the basis for subsequent adjacent object identification and boundary attribute determination. This rule standardizes and quantifies directional determination, and the threshold range can be adjusted according to regional differences and business needs, thereby improving the method's versatility and adaptability in different scenarios, such as meandering rivers, broken channels, winding reservoir shorelines, and complex polygonal land parcel shapes.

[0035] Furthermore, in step S40, the boundary determination of boundary segments, if the partition spans two directions, then the boundary attribute simultaneously includes both directions; each minimum boundary segment is adjacent to only one spatial management scope unit. Assuming multiple adjacencies exist in the spatial data, a boundary point exists at the intersection of multiple adjacent segments, contradicting the principle of "decomposing into indivisible minimum boundary segments." A spatial management scope unit refers to the smallest business object with clear boundaries and independent management attributes within the spatial management scope, such as a land parcel, a plot of land acquired for water conservancy resettlement, a section of river or lake management area, or a protected area. In this invention, the adjacency determination of boundary segments is performed on spatial management scope units.

[0036] In some embodiments, the preset determination rule for determining the four boundaries of the boundary line segment in step S40 is an eight-direction determination rule, specifically:

[0037] The left side of the North Zone is assigned the westernmost position, and the right side is assigned the easternmost position.

[0038] The northeastern region is assigned the western and northern boundaries to the left side, and the eastern and southern boundaries to the right side.

[0039] The left side of the eastern area is assigned to the north, and the right side is assigned to the south.

[0040] The southeast region is assigned the north and east as its left side, and the south and west as its right side.

[0041] The left side of the South Zone is assigned the easternmost point, and the right side is assigned the westernmost point;

[0042] The left side of the southwest region is assigned the east and south boundaries, and the right side is assigned the west and north boundaries.

[0043] The left side of the western area is assigned to the south, and the right side is assigned to the north.

[0044] The northwest region is assigned the left side as south and west, and the right side as north and east.

[0045] By comprehensively utilizing spatial topology analysis and buffer zone analysis, this method identifies spatial objects on both sides of each boundary line segment, covering both direct and indirect adjacency. It can simultaneously handle complex situations such as multiple land use types adjacent to one side of a river or lake, different management units adjacent to one side of a canal, and multiple plots adjacent to one side of a parcel. The method extracts the identifiers of adjacent objects and their lateral positions (left or right side) and correlates them with the direction classification results to ensure the completeness and accuracy of adjacency identification, reducing omissions caused by insufficient data precision or minor boundary gaps.

[0046] Further, step S50 involves structured attribute storage, specifically writing the direction attribute, adjacent object identifier, determination method, and boundary attributes of each boundary line segment into a uniformly coded structured attribute table. The attribute table fields include line segment ID, azimuth value, direction attribute, adjacent object ID / name, adjacent side location, adjacent determination method, north boundary, south boundary, east boundary, west boundary, and boundary line length. The data is stored according to a unified coding and format standard, consistent with the coding rules of the water conservancy management system and the cadastral management system.

[0047] Based on the zoning direction and adjacent sides, line segments are assigned corresponding boundary attributes according to preset rules. This considers zoning situations spanning two directions, ensuring that the boundary attributes accurately reflect the actual orientation and adjacency relationships of the line segments in space. The determination results, along with the identifiers of adjacent objects, are written into a uniformly coded structured attribute table, such as adjacent water areas, engineering facilities, and land parcel numbers. This forms a searchable, statistically significant, and exchangeable spatial attribute set, which can seamlessly interface with water conservancy management systems, cadastral management systems, and various GIS platforms, achieving standardized management and sharing of boundary data.

[0048] Furthermore, in step S60, the comprehensive determination of the four boundaries, the business rules are as follows: when there are multiple line segments in the same direction, the cumulative adjacent length is used as the priority sorting basis, and the adjacent object identifier and corresponding area are recorded; direct adjacent objects take precedence over buffer adjacent objects; when there are multiple adjacent objects in the same direction, they are sorted and output according to area, boundary length or business priority.

[0049] The system performs directional merging and adjacency grouping of all boundary segments within the same spatial management area, such as river and lake management boundaries, canal management areas, and land parcel boundary spatial management areas. It calculates the cumulative adjacency length in each direction, prioritizes data according to business rules, and outputs unique and complete boundary information. Leveraging the FME platform, the entire process is modularly encapsulated, enabling automated batch processing across formats and coordinate systems. This significantly reduces manual intervention, improves processing efficiency and result consistency, and can process large-scale datasets of rivers, lakes, canals, and land parcels in a single operation, meeting the high-efficiency and standardized needs of multiple industries, including river and lake management, water resource protection, land registration, and real estate registration. Besides FME, the operating platform can also be an open-source GIS toolchain, such as GDAL / OGR, QGIS, or Python. In addition to running on desktop environments, it can be deployed as a server-side application for online batch processing; deployed as a distributed task on cloud computing platforms, such as AWS Lambda or Google Cloud Functions; and combined with mobile mapping applications to achieve real-time automatic determination of the boundaries of the management area.

[0050] This invention also provides a spatial management range boundary quantification determination system based on boundary decomposition, comprising the following modules:

[0051] Data Input and Preprocessing Module: Receives and reads multi-source spatial management scope data, including water conservancy management boundaries and land parcel boundaries, supporting multiple formats such as Shapefile, GeoDatabase, and CAD; automatically identifies the coordinate system type as geographic coordinate system or projected coordinate system; for files lacking coordinate system attributes, the coordinate system is manually specified; performs unified coordinate system transformation to ensure that data from different sources are processed under the same spatial reference system; performs topology checks, cleaning up redundant nodes, dangling lines, and duplicate points; and combines buffer preprocessing to correct minor gaps or accuracy deviations in boundaries, ensuring boundary closure and topological correctness, adapting to various scenarios such as river and lake shorelines, channel polylines, and irregular land parcel boundaries.

[0052] Boundary decomposition and azimuth calculation module: Based on the spatial topology, closed boundary lines such as river and lake shoreline segments, channel segments, and land parcel boundary segments are decomposed into indivisible minimum boundary segments; a length threshold filtering mechanism is introduced to remove short, unstable segments that are easily affected by local boundary jitter or deformation; under a unified projection coordinate system, the azimuth angle of the filtered segments is calculated independently to generate high-precision and stable basic direction data; the minimum boundary segment dataset containing azimuth angles is output as the basis for subsequent direction classification and adjacency determination.

[0053] Direction classification and adjacent object identification module: Based on a preset and adjustable azimuth threshold range, the line segments are divided into directional groups; combined with spatial topology analysis, the spatial objects on both sides of each line segment are identified: one side is the current management area, and the other side is the adjacent management area or other spatial objects with clear boundaries; the adjacent object identifier is extracted and its position is recorded; for boundary cases with small gaps or data precision differences, the adjacency analysis of the buffer zone is used to supplement the determination of the adjacency relationship; each minimum boundary line segment is adjacent to only one management unit.

[0054] Boundary segment boundary determination module: Assign boundary attributes to segments based on directional partitions and adjacent sides; for partitions spanning two directions, the boundary attributes are allowed to include both directions simultaneously;

[0055] The structured attribute storage module writes the line segment's boundary attributes, adjacent object identifiers, azimuth values, location on the side, and determination method into a uniformly coded structured attribute table. The attribute table fields include: line segment ID, azimuth value, direction attribute, adjacent object ID / name, adjacent location on the side, adjacency determination method, north boundary, south boundary, east boundary, west boundary, and boundary line length. It is stored according to a unified coding and format standard to ensure consistency with the coding of the water conservancy management system and the land registration management system.

[0056] The boundary determination module merges and removes duplicates of the boundary attributes of all boundary segments within the same management area. When multiple segments exist in the same direction, the cumulative adjacent length is used as the priority sorting basis, and the adjacent object identifier and corresponding area are recorded. Direct adjacent objects are prioritized over buffer adjacent objects according to business rules. When multiple adjacent objects exist in the same direction, they are sorted and output according to area, boundary length, or business priority. The module outputs unique and complete boundary information for the management area.

[0057] Batch Automated Processing Module: Builds automated workflows on the FME platform, modularizing each processing step; supports batch execution across formats and coordinate systems; supports logic such as conditional branching and loop processing to ensure stable operation under different data conditions; batch processes multiple datasets within a management scope, reducing manual intervention and improving efficiency and consistency.

[0058] Output and Data Interface Module: Outputs the boundary information of the management area in a structured format; supports data interface with water conservancy management systems, cadastral management systems, land ownership confirmation systems, real estate registration systems, etc.; can generate standard GIS data files, such as Shapefile, GeoJSON, GDB, etc., or write them directly to the database.

[0059] The output data format of each module is compatible with the input format of the next module, ensuring the stability and scalability of the processing chain. In the FME workflow, each module is implemented as an independent Transformer node, supporting processing logic such as conditional branching and batch looping.

[0060] This invention is particularly applicable to business scenarios in the water conservancy industry, including river and lake management, water resource protection, water conservancy project operation and maintenance, irrigation district management, and water area ownership demarcation. It addresses the shortcomings of existing water conservancy management boundary extraction methods in terms of efficiency, accuracy, batch processing capabilities, and adaptability to complex boundaries. It provides an efficient, accurate, and standardized technical solution for boundary management, ownership demarcation, and spatial data sharing and exchange in the water conservancy industry. Simultaneously, this method can be extended to other spatial boundary management fields such as land ownership confirmation, real estate registration, cadastral management, and land resource surveys, achieving cross-industry versatility and standardization. It is also applicable to the quantitative determination of the boundaries of other spatial objects with clearly defined boundaries, such as land parcels, land ownership units, real estate registration areas, nature reserves, and agricultural irrigation areas.

[0061] The beneficial effects of this invention are:

[0062] 1. The method of this invention uses spatial topology analysis to decompose the closed boundary of the management area into indivisible minimum boundary segments. Azimuth angles are calculated based on these minimum boundary segments after length threshold filtering, avoiding directional deviations caused by reliance on the geometric center or circumscribed rectangle. The azimuth angle is then calculated independently for each segment, ensuring that the direction determination is based on the actual boundary segment rather than an approximation of the overall geometric center. Adjustable numerical thresholds are used for direction classification, ensuring consistency of the determination criteria across different regions and data precision conditions. The adjacency determination employs a dual adjacency determination strategy of spatial topology analysis and buffer analysis. When dealing with complex scenarios such as irregular river and lake shorelines, channel orientations, and multiple boundaries and adjacencies of land parcels, the consistency between the direction and adjacency results and manually interpreted reference data is significantly improved. This reduces the incidence of misjudgments and omissions while ensuring the legal validity and business reliability of the boundary information in ownership delimitation.

[0063] 2. This invention's system relies on the FME platform to construct a fully automated workflow, modularizing steps such as boundary decomposition, azimuth calculation, direction classification, adjacency determination, attribute assignment, and direction merging, achieving automated sequential processing. It supports automatic identification and conversion of multi-source data formats and multi-coordinate systems, reducing manual data preparation time. It supports batch processing of multiple management scope datasets at once, avoiding repetitive manual operations. The output boundary information uses a structured attribute table with unified encoding, conforming to the encoding and format standards of the water conservancy management system and the cadastral management system, and directly interfaces with business systems. This not only facilitates retrieval, statistics, and analysis but also ensures seamless data interoperability across systems and platforms, thereby improving data usability and sharing efficiency. Attached Figure Description

[0064] Figure 1 This is a schematic diagram of the parcel boundary decomposition before the decomposition in Example 1;

[0065] Figure 2 This is a schematic diagram of the decomposed parcel boundary after Example 1.

[0066] Figure 3 This is a schematic diagram of the adjacent boundary buffer and the adjacent determination buffer in Example 1;

[0067] Figure 4 A schematic diagram illustrating the establishment of a buffer zone at the adjacent boundary in Example 1;

[0068] Figure 5 This is a schematic diagram of azimuth threshold direction classification in Example 1;

[0069] Figure 6 This is a schematic diagram of the connection relationships and data flow paths of the determination system in Example 2. Detailed Implementation

[0070] The present invention will now be described in detail with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0071] Example 1

[0072] A method for quantifying the boundaries of a spatial management area based on boundary decomposition, characterized by the following steps:

[0073] S10. Spatial management scope data reading and preprocessing: Input multi-source spatial management scope data files, which include water conservancy management boundaries and land parcel boundaries. Identify the coordinate system type of the data. For data lacking coordinate system attributes, the coordinate system is manually specified. Perform format and coordinate system checks on the input multi-source spatial management scope data. Convert data from different sources into a regionally unified projected coordinate system. Perform topology checks, clean up redundant nodes, hanging line segments, and duplicate points, and correct boundary data using buffer preprocessing methods.

[0074] S20. Boundary decomposition and azimuth calculation, please refer to the appendix. Figure 1-2The diagram illustrates the decomposition of land parcel boundaries. Under a unified projection coordinate system, based on spatial topology, the closed boundary line is decomposed into indivisible minimum boundary segments. Each minimum boundary segment is a continuous boundary unit with boundary points at both ends and no other boundary points in between, ensuring that each segment has a clear start and end point. Segments are filtered according to a length threshold, retaining only those with a length not less than the set threshold. Subsequently, the arctangent function is used to calculate the azimuth angle of the filtered segments to obtain azimuth angle data. The closed boundary includes river and lake shorelines, canal orientations, water conservancy project management boundaries, and land parcel boundaries.

[0075] S30. Direction Classification and Adjacent Object Identification: Based on the acquired azimuth data, line segments are divided into eight directional groups according to a preset and adjustable azimuth threshold. Spatial topology analysis is used to identify spatial objects on both sides of each line segment. One side represents the current management area, and the other side represents the adjacent management area or other spatial objects with clear boundaries. The identifiers of the adjacent objects are extracted and their lateral positions are recorded, and this information is correlated with the direction classification results. Please refer to the appendix. Figure 3-4 The diagram illustrates the adjacency determination buffer. The method combines spatial topology analysis to identify spatial objects on both sides of each line segment. If minor gaps or differences in data precision exist at boundaries, adjacency analysis within the buffer is used for supplementary determination. A minor gap refers to a shortest distance between the boundaries of two spatial objects that is less than a certain set threshold. This threshold is typically set to a value that matches the data acquisition precision or coordinate units, such as 0.01 meters to 1 meter, calculated as the equivalent projected distance in the geographic coordinate system.

[0076] In this embodiment, the line segment is divided into North, Northeast, East, Southeast, South, Southwest, West, and Northwest directional groups based on the acquired azimuth data. Please refer to the appendix. Figure 5 The azimuth threshold is set as follows:

[0077] North region (330°, 360°] ∪ [0°, 30°);

[0078] Northeast region [30°, 60°];

[0079] Eastern zone (60°, 120°);

[0080] Southeast region [120°, 150°];

[0081] South zone (150°, 210°);

[0082] Southwest region [210°, 240°];

[0083] West zone (240°, 300°);

[0084] Northwest region [300°, 330°].

[0085] S40. Boundary segment determination: Based on the partition direction of the segment and the lateral position of the adjacent object, the boundary attributes are assigned according to the preset determination rules. If the partition spans two directions, the boundary attributes include both directions. Each minimum boundary segment is adjacent to only one management unit.

[0086] The preset determination rule is an eight-directional determination rule, specifically:

[0087] The left side of the North Zone is assigned the westernmost position, and the right side is assigned the easternmost position.

[0088] The northeastern region is assigned the western and northern boundaries to the left side, and the eastern and southern boundaries to the right side.

[0089] The left side of the eastern area is assigned to the north, and the right side is assigned to the south.

[0090] The southeast region is assigned the north and east as its left side, and the south and west as its right side.

[0091] The left side of the South Zone is assigned the easternmost point, and the right side is assigned the westernmost point;

[0092] The left side of the southwest region is assigned the east and south boundaries, and the right side is assigned the west and north boundaries.

[0093] The left side of the western area is assigned to the south, and the right side is assigned to the north.

[0094] The northwest region is assigned the left side as south and west, and the right side as north and east.

[0095] S50. Structured attribute storage: The direction attribute, adjacent object identifier, determination method, and four-boundary attribute of each boundary line segment are written into a structured attribute table with unified coding. The attribute table fields include line segment ID, azimuth value, direction attribute, adjacent object ID / name, adjacent side location, adjacent determination method, north boundary, south boundary, east boundary, west boundary, and boundary line length. It is stored according to unified coding and format standards, consistent with the coding rules of the water conservancy management system and the cadastral management system.

[0096] S60, Boundary Comprehensive Determination: For all boundary segments within the same management area, directional merging and deduplication are performed. For multiple segments in the same direction, they are grouped according to the adjacent object identifier. The cumulative adjacent length of the adjacent boundary is calculated as the priority sorting basis, and the identifier and corresponding area of ​​the adjacent object are recorded. Priority determination is performed according to business rules, and complete and unique boundary information is output.

[0097] Specifically, the business rules are as follows: when there are multiple line segments in the same direction, the cumulative adjacency length is used as the priority sorting basis, and the adjacency object identifier and corresponding area are recorded; direct adjacency objects take precedence over buffer adjacency objects; when there are multiple adjacency objects in the same direction, they are sorted and output according to area, boundary length or business priority.

[0098] S70. Output and system interface: Perform the above processing steps in batches across formats and coordinate systems, generate standard GIS data files or write them to the database, and interface with the water conservancy management system and land registration management system.

[0099] Example 2

[0100] A spatial management range boundary quantification system based on boundary decomposition is described in the appendix. For the connection relationships between modules and data flow paths, please refer to the appendix. Figure 6 ,include:

[0101] Data Input and Preprocessing Module: Receives and reads multi-source spatial management scope data, including water conservancy management boundaries and land parcel boundaries, supporting multiple formats such as Shapefile, GeoDatabase, and CAD; automatically identifies the coordinate system type as geographic coordinate system or projected coordinate system; for files lacking coordinate system attributes, the coordinate system is manually specified; performs unified coordinate system transformation to ensure that data from different sources are processed under the same spatial reference system; performs topology checks, cleaning up redundant nodes, dangling lines, and duplicate points; and combines buffer preprocessing to correct minor gaps or accuracy deviations in boundaries, ensuring boundary closure and topological correctness, adapting to various scenarios such as river and lake shorelines, channel polylines, and irregular land parcel boundaries.

[0102] Boundary decomposition and azimuth calculation module: Based on the spatial topology, closed boundary lines such as river and lake shoreline segments, channel segments, and land parcel boundary segments are decomposed into indivisible minimum boundary segments; a length threshold filtering mechanism is introduced to remove short, unstable segments that are easily affected by local boundary jitter or deformation; under a unified projected coordinate system, the azimuth angle of the filtered segments is independently calculated using the arctangent function to generate high-precision and stable basic direction data; the minimum boundary segment dataset containing azimuth angles is output as the basis for subsequent direction classification and adjacency determination.

[0103] Direction classification and adjacent object identification module: Based on a preset and adjustable azimuth threshold range, the line segments are divided into directional groups; combined with spatial topology analysis, the spatial objects on both sides of each line segment are identified: one side is the current management area, and the other side is the adjacent management area or other spatial objects with clear boundaries; the adjacent object identifier is extracted and its position is recorded; for boundary cases with small gaps or data precision differences, the adjacency analysis of the buffer zone is used to supplement the determination of the adjacency relationship; each minimum boundary line segment is adjacent to only one management unit.

[0104] Boundary segment boundary determination module: Assign boundary attributes to segments based on directional partitions and adjacent sides; for partitions spanning two directions, the boundary attributes are allowed to include both directions simultaneously;

[0105] The structured attribute storage module writes the line segment's boundary attributes, adjacent object identifiers, azimuth values, location on the side, and determination method into a uniformly coded structured attribute table. The attribute table fields include: line segment ID, azimuth value, direction attribute, adjacent object ID / name, adjacent location on the side, adjacency determination method, north boundary, south boundary, east boundary, west boundary, and boundary line length. It is stored according to a unified coding and format standard to ensure consistency with the coding of the water conservancy management system and the land registration management system.

[0106] The boundary determination module merges and removes duplicates of the boundary attributes of all boundary segments within the same management area. When multiple segments exist in the same direction, the cumulative adjacent length is used as the priority sorting basis, and the adjacent object identifier and corresponding area are recorded. Direct adjacent objects are prioritized over buffer adjacent objects according to business rules. When multiple adjacent objects exist in the same direction, they are sorted and output according to area, boundary length, or business priority. The module outputs unique and complete boundary information for the management area.

[0107] Batch Automated Processing Module: Builds automated workflows on the FME platform, modularizing each processing step; supports batch execution across formats and coordinate systems; supports logic such as conditional branching and loop processing to ensure stable operation under different data conditions; batch processes multiple datasets within a management scope, reducing manual intervention and improving efficiency and consistency.

[0108] Output and Data Interface Module: Outputs the boundary information of the management area in a structured format; supports data interface with water conservancy management systems, cadastral management systems, land ownership confirmation systems, real estate registration systems, etc.; can generate standard GIS data files, such as Shapefile, GeoJSON, GDB, etc., or write them directly to the database.

[0109] The output data format of each module is compatible with the input format of the next module, ensuring the stability and scalability of the processing chain. In the FME workflow, each module is implemented as an independent Transformer node, supporting processing logic such as conditional branching and batch looping.

[0110] Although the present invention has been described in detail above with general descriptions, specific embodiments, and accompanying drawings, the scope of protection of the present invention is not limited thereto. Modifications or improvements can be made to the present invention, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for quantitatively determining the boundaries of a spatial management area based on boundary decomposition, characterized in that, Includes the following steps: S10. Spatial management scope data reading and data preprocessing: Input multi-source spatial management scope data files, automatically identify the coordinate system type of the data, convert it to a unified coordinate system, perform topology structure checks and clean up redundancy, and correct boundary data by combining buffer preprocessing methods. S20. Boundary decomposition and azimuth calculation: The closed boundary line is decomposed into the smallest indivisible boundary segment. The smallest boundary segment is a continuous boundary unit with boundary points at both ends and no other boundary points in the middle. The segments are filtered according to the length threshold, and then the azimuth of the filtered segments is calculated to obtain the azimuth data. The boundary decomposition and azimuth calculation are specifically as follows: under a unified projection coordinate system, based on the spatial topology, the closed boundary line is decomposed into the smallest indivisible boundary segment. The smallest boundary segment is a continuous boundary unit with boundary points at both ends and no other boundary points in the middle. The segments are filtered according to a length threshold, and only the part with a length not less than the set threshold is retained. Then, the azimuth of the filtered segments is calculated to obtain the azimuth data. The closed boundary includes river and lake shorelines, channel orientation, water conservancy project management boundaries, and land parcel boundaries. S30. Direction classification and adjacent object identification: Based on the acquired azimuth data, the line segment is divided into eight partition directions according to the preset azimuth threshold range. The spatial topology analysis method identifies the spatial objects on both sides of each line segment, extracts the identifiers of adjacent objects and records their side positions, and associates them with the direction classification results. The direction classification and adjacent object identification specifically involves dividing the line segment into eight directional groups based on the acquired azimuth data and a preset and adjustable azimuth threshold. A spatial topology analysis method is then used to identify the spatial objects on both sides of each line segment. One side represents the current management area, and the other side represents the adjacent management area or other spatial objects with clear boundaries. The identifiers of the adjacent objects are extracted, their lateral positions are recorded, and this information is correlated with the direction classification results. If there are boundary gaps that meet the set threshold conditions or boundary discontinuities due to differences in data acquisition accuracy, buffer adjacency analysis is used for supplementary determination. S40. Boundary segment boundary determination: Based on the partition direction of the segment and the lateral position of the adjacent object, the boundary attributes are assigned according to the preset determination rules. S50. Structured attribute storage: The direction attribute, adjacent object identifier, determination method and four-boundary attribute of each boundary line segment are written into a structured attribute table with unified coding and stored according to unified coding and format standards, consistent with the coding rules of the water conservancy management system and land registration management system. S60, Boundary Comprehensive Determination: Merge and deduplicate all boundary segments within the same management area in terms of direction; group multiple segments in the same direction according to the adjacent object identifier; calculate the cumulative adjacent length of the adjacent boundary as the priority sorting basis; record the identifier and corresponding area of ​​the adjacent object; determine the priority according to the business rules; and output complete and unique boundary information. The business rules are as follows: when there are multiple line segments in the same direction, the cumulative adjacent length is used as the priority sorting basis, and the adjacent object identifier and corresponding area are recorded; direct adjacent objects take precedence over buffer adjacent objects; when there are multiple adjacent objects in the same direction, they are sorted and output according to area, boundary length or business priority. S70. Output and system interface: Perform the above processing steps in batches across formats and coordinate systems, generate standard GIS data files or write them to the database, and interface with the water conservancy management system and land registration management system.

2. The spatial management range boundary quantification determination method based on boundary decomposition according to claim 1, characterized in that, The spatial management scope data reading and preprocessing specifically involves: inputting a multi-source spatial management scope data file, which includes water conservancy management boundaries and land parcel boundaries; identifying the coordinate system type of the data; manually specifying the coordinate system for data lacking coordinate system attributes; checking the format and coordinate system of the input multi-source spatial management scope data; converting data from different sources into a regionally unified projected coordinate system; performing topology checks; cleaning up redundant nodes, dangling lines, and duplicate points; and correcting boundary data using buffer preprocessing.

3. The spatial management range boundary quantification determination method based on boundary decomposition according to claim 1, characterized in that, Based on the acquired azimuth data, the line segment is divided into North, Northeast, East, Southeast, South, Southwest, West, and Northwest directional groups, with the azimuth threshold set as follows: North region (330°, 360°] ∪ [0°, 30°); Northeast region [30°, 60°]; Eastern zone (60°, 120°); Southeast region [120°, 150°]; South zone (150°, 210°); Southwest region [210°, 240°]; West zone (240°, 300°); Northwest region [300°, 330°].

4. The spatial management range boundary quantification determination method based on boundary decomposition according to claim 1, characterized in that, In the determination of the boundaries of the boundary line segment, if the partition spans two directions, the boundary attribute includes both directions simultaneously; each minimum boundary line segment is adjacent to only one spatial management range unit.

5. The spatial management range boundary quantification determination method based on boundary decomposition according to claim 1, characterized in that, In the determination of the four boundaries of the boundary line segment, the preset determination rule is an eight-direction determination rule, specifically: The left side of the North Zone is assigned the westernmost position, and the right side is assigned the easternmost position. The northeastern region is assigned the western and northern boundaries to the left side, and the eastern and southern boundaries to the right side. The left side of the eastern area is assigned to the north, and the right side is assigned to the south. The southeast region is assigned the north and east as its left side, and the south and west as its right side. The left side of the South Zone is assigned the easternmost point, and the right side is assigned the westernmost point; The left side of the southwest region is assigned the east and south boundaries, and the right side is assigned the west and north boundaries. The left side of the western area is assigned to the south, and the right side is assigned to the north. The northwest region is assigned the left side as south and west, and the right side as north and east.

6. The spatial management range boundary quantification determination method based on boundary decomposition according to claim 1, characterized in that, The structured attribute storage specifically involves writing the direction attribute, adjacent object identifier, determination method, and four-boundary attribute of each boundary line segment into a uniformly coded structured attribute table. The structured attribute table fields include line segment ID, azimuth value, direction attribute, adjacent object ID, adjacent side location, adjacent determination method, north boundary, south boundary, east boundary, west boundary, and boundary line length. It is stored according to a unified coding and format standard, consistent with the coding rules of the water conservancy management system and the cadastral management system.

7. A spatial management range boundary quantification determination system based on boundary decomposition, characterized in that, The system is used to perform the method according to any one of claims 1-6, and includes the following modules: Data input and preprocessing module: Used to receive and read multi-source spatial management scope data, including water conservancy management boundaries and parcel boundaries, automatically identify the coordinate system type as geographic coordinate system or projected coordinate system, for files with missing coordinate system attributes, manually specify the coordinate system path, perform unified coordinate system transformation, perform topology structure check, clean up redundant nodes, hanging line segments and duplicate points, and correct boundary data in combination with buffer preprocessing. Boundary decomposition and azimuth calculation module: Based on the spatial topology, it decomposes the closed boundary line into the smallest indivisible boundary segments, filters the segments with a length threshold filtering mechanism, calculates the azimuth angle of the filtered segments independently under a unified projection coordinate system, generates basic direction data, and outputs a dataset of the smallest boundary segments containing the azimuth angle as the basis for subsequent direction classification and adjacency determination. Direction Classification and Adjacent Object Recognition Module: Used for direction classification, dividing line segments into eight directional groups based on a preset and adjustable azimuth threshold range; Adjacent object recognition, combined with spatial topology analysis, identifies spatial objects on both sides of each line segment, with one side being the current management range and the other side being the adjacent management range or other spatial objects with clear boundaries; extracts adjacent object identifiers and records their lateral positions; for boundary gaps that meet set threshold conditions or boundary discontinuities caused by differences in data acquisition accuracy, buffer adjacency analysis is used to supplement the determination of adjacency relationships; Boundary Segment Determination Module: Used to assign boundary attributes to segments based on directional partitions and adjacent sides; for partitions spanning two directions, the boundary attributes simultaneously include both directions; Structured attribute storage module: Used to write the boundary attributes, adjacent object identifiers, azimuth values, location and determination method of line segments into a structured attribute table with unified coding, and store them according to unified coding and format standards, consistent with the coding of water conservancy management system and land registration management system; The structured attribute table includes the following fields: line segment ID, azimuth value, direction attribute, adjacent object ID, adjacent side location, adjacent determination method, north, south, east, west, and boundary line length. The boundary determination module is used to merge and deduplicate the boundary attributes of all boundary segments within the same management area. When multiple segments exist in the same direction, the cumulative adjacent length is used as the priority sorting basis, and the adjacent object identifier and corresponding area are recorded. Directly adjacent objects take precedence over buffer adjacent objects according to business rules. When multiple adjacent objects exist in the same direction, the management area boundary information is output in order of area, boundary length, or business priority. Batch Automated Processing Module: Used to build automated workflows on the FME platform, modularize each processing step, batch process and manage datasets, support batch execution across formats and coordinate systems, support conditional branching and loop processing logic, and ensure stable operation under different data conditions; Output and Data Interface Module: Used to output the boundary information of the management area in a structured format, and to interface with the water conservancy management system, cadastral management system, land ownership confirmation system, and real estate registration system to generate standard GIS data files or directly write them into the database.

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