A Method for Site Selection and Responsibility Zone Delineation of Emergency Shelters to Cope with Population Fluctuations

Abstract

This invention discloses a method for selecting emergency shelter sites and delineating responsibility zones in response to population fluctuations, comprising: screening potential emergency shelter sites based on open space vector data; establishing an adjacency matrix and network distance matrix between urban plots, as well as a spatial relationship matrix between potential emergency shelter sites and urban plots; selecting one scheme from all potential emergency shelter combination schemes, generating an initial responsibility zone delineation scheme according to the nearest neighbor principle and calculating the population fluctuation coefficient; finding exchangeable plots corresponding to each responsibility zone, randomly exchanging one urban plot as a new responsibility zone delineation scheme, and recalculating the population fluctuation coefficient; repeating the process until all responsibility zone delineation schemes that meet the conditions and their corresponding population fluctuation coefficients are obtained; selecting the preferred scheme according to the population fluctuation coefficient, calculating the effective refuge area gap, and selecting the preferred scheme with the smallest effective refuge area gap as the optimal scheme.

Description

Technical Field

[0001] This invention relates to the field of spatial information technology, and in particular to a method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations. Background Technology

[0002] Emergency shelter planning is a crucial aspect of urban planning and management. According to legal provisions and national policies, nationwide emergency shelter planning is required at five levels: provincial, municipal, county (district), township (street), and village (community). Addressing population fluctuations has long been a major challenge in urban emergency shelter planning.

[0003] Current emergency shelter planning is mainly based on geographic information systems. Shelters are determined through suitability assessments, and then responsibility areas are delineated using methods such as neighborhood analysis and network analysis. In terms of responding to population fluctuations, the main approach is to adjust the spatial capacity of emergency shelters after the site selection and responsibility area delineation are completed.

[0004] Existing technologies treat the selection of emergency shelter sites, the division of responsibility areas, and the allocation of space capacity as three sequentially dependent steps, and carry out the planning work in these three aspects in a linear process. However, they lack the correlation and optimization of these three aspects, require human judgment and operation, and are not effective in dealing with population fluctuations, thus failing to meet the real-time and fluctuating needs of emergency shelters. Summary of the Invention

[0005] This invention provides a method for selecting emergency shelter locations and delineating responsibility zones in response to population fluctuations. Under constraints of regulatory requirements, practical conditions, management methods, and behavioral habits, and with the optimization goal of reducing population fluctuations and ensuring capacity matching, it utilizes a computer to generate all reasonable solutions and performs correlation optimization of emergency shelter location selection, responsibility zone delineation, and spatial capacity allocation. It automatically generates optimized solutions for emergency shelter location selection and responsibility zone delineation, as detailed below:

[0006] A method for selecting emergency shelter sites and delineating responsibility zones in response to population fluctuations, the method comprising the following steps:

[0007] ① Conduct spatial analysis based on the processed urban land parcel data and establish an adjacency matrix between urban land parcels;

[0008] ② Based on the open space vector data of the target area, potential emergency shelters are screened, and relevant information is integrated into the urban land data to export the urban land information table;

[0009] ③ Based on the processed urban plot data and processed road network data, network analysis is carried out to establish a network distance matrix between urban plots and to reclassify the network distances to obtain a spatial relationship matrix between potential emergency shelters and urban plots.

[0010] ④ Construct the coverage plot vector for each potential emergency shelter, and use an exhaustive method to solve for the minimum number of potential emergency shelters covering the entire target area, as well as all possible combinations of potential emergency shelters;

[0011] ⑤ Select any one of the potential emergency shelter combinations and generate an initial responsibility zone division scheme based on the nearest neighbor principle;

[0012] ⑥ Calculate the population fluctuation coefficient of the previous responsibility area division scheme based on the real-time population data of each plot at each time point;

[0013] ⑦ Based on the adjacency matrix between urban plots and the spatial relationship matrix between potential emergency shelters and urban plots, find the exchangeable plots corresponding to each responsibility area, and randomly select one urban plot from the exchangeable plots to exchange as a new responsibility area division scheme.

[0014] ⑧ Repeat steps ⑥-⑦ until all responsibility zone division schemes and corresponding population fluctuation coefficients are obtained under a potential emergency shelter combination scheme;

[0015] ⑨ Repeat steps ⑤-⑧ to obtain all responsibility area division schemes and corresponding population fluctuation coefficients under all potential emergency shelter combination schemes. Select several responsibility area division schemes that are close to the minimum population fluctuation coefficient as the preferred schemes.

[0016] ⑩ Calculate the effective refuge area gap for each preferred option, select the preferred option with the smallest effective refuge area gap as the optimal option, and output the potential emergency refuge site combination scheme and responsibility area division scheme in the optimal scheme; based on the final results, carry out emergency refuge site selection and responsibility area division to cope with emergency refuge needs under population fluctuation conditions.

[0017] The processed urban land parcel data and the processed road network data are as follows:

[0018] Acquire urban land parcel data, road network data, and spatial isolation data within the target area;

[0019] The urban land parcel data is preprocessed using road network data. The boundaries of the urban land parcels facing the street are extended to the center line of the nearby road, while the original parcel IDs are retained. The resulting first urban land parcel data is the processed urban land parcel data.

[0020] By utilizing spatial isolation data, the road network data is preprocessed. The main urban roads that serve as spatial isolation elements are converted from single-line to parallel double-line roads, and the roads at the locations of other spatial isolation elements are disconnected. The resulting first road network data is the processed road network data.

[0021] Specifically, the spatial analysis based on the processed urban land parcel data, establishing an adjacency matrix between urban land parcels, is as follows:

[0022] Using ArcGIS's Area Neighborhood tool, input the first city's land parcel data, select the parcel ID in the field report, check "Include both sides of the neighborhood relationship", and output the adjacency table;

[0023] Construct an adjacency matrix between urban land parcels based on the adjacency table. The row and column numbers are the land parcel IDs, and the adjacency value is 1 or 0, representing "adjacent" and "not adjacent" respectively.

[0024] Specifically, the open space vector data based on the target area is used to screen potential emergency shelters, and the relevant information is integrated into the urban land parcel data to derive the urban land parcel information table as follows:

[0025] Obtain open space vector data of the target area, use ArcGIS's Add Geometry Attribute tool to add area attributes to the open space vector data, rename the generated polygon area field to "Effective Refuge Area" to obtain the data of the first potential emergency refuge site;

[0026] From the data of the first potential emergency shelter, elements are selected and exported according to the preset principles of functional type, scale, elevation, and slope to obtain the data of the second potential emergency shelter.

[0027] Using ArcGIS's spatial connection tool, select the first city plot data as the target feature, select the second potential emergency shelter data as the connection feature, select one-to-one connection for the connection operation, check "keep all target features", select "effective shelter area" for the field mapping of the connection feature, and select "include" for the matching option. This will integrate the information of the second potential emergency shelter into the first city plot data, resulting in the second city plot data. Then, export the attribute table of the second city plot data as a city plot information table.

[0028] Specifically, network analysis is conducted based on the processed urban land parcel data and road network data to establish a network distance matrix between urban land parcels. The network distances are then reclassified to obtain a spatial relationship matrix between potential emergency shelters and urban land parcels.

[0029] Using ArcGIS's feature conversion tool, input the second city plot data to obtain the city plot center point data;

[0030] Using ArcGIS's Create OD Cost Matrix Analysis Layer tool, select the third road network data as the network data source to generate a start-destination cost matrix containing six layers: start point, destination point, line, point obstacle, line obstacle, and area obstacle. Input the city parcel center point data as the start point and destination point respectively, run network analysis to obtain a new line layer, and export its attribute table as the city parcel center point network distance table.

[0031] Construct a network distance matrix between urban plots based on the network distance table of urban plot center points, where the row number is the plot ID of the urban plot and the column number is the plot ID of the potential emergency shelter.

[0032] Based on the threshold, the network distance between potential emergency shelters and urban plots is reclassified into three categories: very close, adjacent, and not adjacent, represented by 2, 1, and 0 respectively, to obtain the spatial relationship matrix between potential emergency shelters and urban plots.

[0033] The process of constructing the coverage plot vector for each potential emergency shelter involves using an exhaustive method to determine the minimum number of potential emergency shelters covering the entire target area, as well as all possible combinations of potential emergency shelters:

[0034] In the urban land parcel information table, filter the land parcel IDs that have potential emergency shelters, extract the corresponding columns from the spatial relationship matrix between potential emergency shelters and urban land parcels, and obtain the vector of land parcels covered by potential emergency shelters.

[0035] From all potential emergency shelter coverage area vectors, randomly select i and add them together. Iterate through all possibilities and check whether all elements of the new vector obtained by addition are non-zero. i starts from 1 and increases sequentially and checks. If the above condition is not met, increase the number of selections until the above condition is met. At this time, output the number of selections as the planned number of emergency shelters, as well as all combinations of potential emergency shelter coverage area vectors that meet the conditions.

[0036] Convert all combinations of potential emergency shelter coverage plot vectors that meet the conditions into a set of plot IDs, and save the set as a text file "Potential Emergency Shelter Combination Scheme".

[0037] The step of arbitrarily selecting one scheme from all potential emergency shelter combinations and generating an initial responsibility zone division scheme based on the nearest neighbor principle is as follows:

[0038] Select one scheme from the potential emergency shelter combination schemes, construct a set of urban plots for each potential emergency shelter responsibility area included in the scheme, and write the plot ID of the potential emergency shelter into the corresponding urban plot set;

[0039] In the adjacency matrix, search for urban plots that are adjacent to any element in the set of urban plots in the current potential emergency shelter responsibility area; in the network distance matrix, find the minimum network distance between these urban plots and the potential emergency shelters corresponding to the adjacent elements, and add the plot ID of each urban plot to the set of urban plots in the corresponding potential emergency shelter responsibility area.

[0040] Repeat the above steps until all urban plots have been assigned to the set of urban plots within the potential emergency shelter responsibility area, thus obtaining the initial responsibility area division scheme. Save the set of urban plots with the initial responsibility area division scheme as a text file.

[0041] The population fluctuation coefficient of the previous responsibility area division scheme is calculated based on the real-time population data of each land parcel at each time point.

[0042] Acquire real-time population data of plots at multiple consecutive time points, and summarize the real-time population data of plots at each time point according to the previous responsibility area division scheme to obtain the real-time population of responsibility areas at multiple consecutive time points.

[0043] The population mean and standard deviation of each responsibility area at all time points are statistically analyzed, and then the population fluctuation coefficient of each responsibility area is calculated. The population fluctuation coefficients of all responsibility areas are added together to obtain the population fluctuation coefficient of the responsibility area division scheme.

[0044] Specifically, the method of finding exchangeable plots for each responsibility area based on the adjacency matrix between urban plots and the spatial relationship matrix between potential emergency shelters and urban plots, and then randomly selecting one urban plot from the exchangeable plots for exchange as a new responsibility area division scheme, is as follows:

[0045] Based on the adjacency matrix between urban plots, find the adjacent plots of each responsibility area in the previous responsibility area division scheme, and represent them in the form of multiple sets. Eliminate elements that have only one indirectly adjacent plot in the corresponding responsibility area. Based on the spatial relationship matrix between potential emergency shelters and urban plots, eliminate urban plots with a spatial relationship index of 2 with any potential emergency shelter, and obtain the set of exchangeable plots corresponding to each responsibility area.

[0046] Randomly select one plot from the set of exchangeable plots and exchange it to the corresponding responsibility area to generate a new responsibility area division scheme. Save the set of urban plots with the new responsibility area division scheme as a text file.

[0047] Specifically, the effective refuge area gap for each preferred scheme is statistically analyzed, and the preferred scheme with the smallest effective refuge area gap is selected as the optimal scheme. The potential emergency refuge site combination scheme and responsibility area division scheme in the optimal scheme are output as follows:

[0048] Based on the responsibility area division scheme in the preferred scheme and the real-time population data of the plots at all time points, the average population of each responsibility area in each preferred scheme at all time points is calculated.

[0049] Based on the per capita effective refuge area index stipulated in relevant standards, and the average population of each responsibility area in each preferred scheme at all time points, calculate the ideal effective refuge area of ​​each responsibility area in each preferred scheme.

[0050] Using the ideal effective refuge area of ​​each responsibility area in each preferred scheme and the effective refuge area of ​​the corresponding potential emergency refuge sites in the urban land information table, calculate the effective refuge area gap of each preferred scheme;

[0051] The optimal solution is selected based on the smallest gap in effective refuge area. The solution is then output as the combination of potential emergency refuge sites and the division of responsibility areas within that solution.

[0052] The beneficial effects of the technical solution provided by this invention are:

[0053] 1. This invention conducts correlation optimization in three aspects: emergency shelter site selection, responsibility area division, and spatial capacity allocation. The resulting optimization scheme significantly improves the effectiveness in dealing with population fluctuations and meets the real-time and fluctuating requirements of emergency shelters.

[0054] 2. This invention utilizes a computer to generate all reasonable solutions and conduct correlation optimization. The constraints, optimization objectives, and technical solutions are clear and objective, and it can automatically generate emergency shelter site selection and responsibility area division schemes. Attached Figure Description

[0055] Figure 1 A flowchart illustrating a method for selecting locations and delineating responsibility zones for emergency shelters in response to population fluctuations;

[0056] Figure 2 This is a schematic diagram of urban land parcel data preprocessing methods;

[0057] Figure 3 This is a schematic diagram of a road network data preprocessing method based on spatially isolated data. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and specific examples. It should be understood that the specific embodiments described herein are merely intended to explain the present invention and not to limit it. For those skilled in the art, the present invention can be practiced without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples of the invention.

[0059] Current emergency shelter planning methods treat emergency shelter site selection, responsibility area division, and space capacity allocation as three sequentially dependent steps, and carry out planning work in these three aspects in a linear process. However, these three aspects lack interconnected optimization and require human judgment and operation. In terms of responding to population fluctuations, the main approach is to adjust the space capacity of emergency shelters, which is ineffective and cannot meet the real-time and fluctuating needs of emergency shelters.

[0060] Based on the above background, and under the constraints of regulatory requirements, practical conditions, management methods, and behavioral habits, this invention aims to reduce population fluctuations and ensure capacity matching. It utilizes computers to generate all reasonable solutions and conducts correlation optimization of emergency shelter site selection, responsibility area division, and spatial capacity allocation, automatically generating optimized solutions for emergency shelter site selection and responsibility area division.

[0061] To facilitate understanding of this application, the following terms are explained in the embodiments of this invention:

[0062] Emergency shelters are safe places provided for the public to temporarily take refuge, settle and rescue in response to natural disasters (such as earthquakes, floods, typhoons, etc.) or sudden public events (such as fires, explosions, epidemics, etc.). They need to be distributed in a decentralized manner in cities by selecting sites of a certain size.

[0063] The evacuation responsibility area is the predetermined service area of ​​each emergency shelter and also serves as a reference range for the capacity configuration of emergency shelters. According to the national standard "Classification and Classification of Emergency Shelters" (GB / T44013-2024), the service radius of an emergency shelter is within 1000m. Based on residents' behavioral habits, residents within 300m of an emergency shelter often choose to evacuate to the nearest shelter. In order to meet daily management requirements, the evacuation responsibility area must be a continuous area in space and have a relatively regular shape.

[0064] The population capacity of an emergency shelter is the maximum number of people that an emergency shelter can accommodate while meeting basic emergency shelter service requirements.

[0065] Effective refuge area refers to the effective area within an emergency refuge site that can be used for emergency shelter, refuge and resettlement of emergency personnel, and storage of emergency facilities, equipment and supplies.

[0066] The effective refuge area per capita refers to the effective refuge area available to each person in an emergency shelter. Numerically, it is equal to the effective refuge area divided by the population capacity. The national standard "Classification and Grading of Emergency Shelters" (GB / T44013-2024) stipulates that the effective refuge area per capita should not be less than 1.5㎡ / person.

[0067] Urban land parcel data refers to independent development parcels with the same function within a city, which are the basic units of urban development and management. The urban land parcel data required in this embodiment of the invention includes area vector graphics and fields such as land parcel ID.

[0068] The population data of the land parcels, real-time population data at the urban land parcel scale, the population data of the land parcels required in this embodiment of the invention is in tabular form, including land parcel ID and population at multiple time points.

[0069] Spatial isolation data refers to data on insurmountable spatial isolation elements in cities under emergency conditions. Common spatial isolation elements include rivers, railways, and major urban roads.

[0070] The adjacency matrix represents the spatial adjacency and shared edge relationships between multiple city plots. It uses Boolean values, with a value of 1 when plots are adjacent and a value of 0 when plots are not adjacent or when there is spatial isolation.

[0071] The network distance matrix is ​​used to represent the actual distance between multiple urban plots based on the urban walking network. The embodiments of the present invention are based on the urban road network and use network analysis for calculation, and the calculation results are close to the actual walking distance.

[0072] Potential emergency shelters refer to open urban spaces that meet the requirements of shelter standards. Referring to the national standard "Classification and Grading of Emergency Shelters" (GB / T44013-2024) published in 2024, this embodiment of the invention selects open spaces in flat areas that meet the standard requirements and have a certain shelter area as potential emergency shelters, including urban parks, open squares, ground parking lots, school playgrounds, etc.

[0073] The population fluctuation coefficient is an index that reflects population fluctuations within a certain time and space range. In this embodiment of the invention, it is measured by the ratio of the standard deviation to the mean of population changes at multiple consecutive time points.

[0074] Example 1

[0075] To address the technical problems existing in the background art, embodiments of the present invention provide a method for selecting emergency shelter locations and delineating responsibility areas in response to population fluctuations. This method includes the following steps:

[0076] Figure 1 This invention provides a method for selecting emergency shelter locations and delineating responsibility zones to address population fluctuations, as illustrated in the embodiments of the present invention. Figure 1 As shown, the method for selecting emergency shelter sites and dividing responsibility areas in response to population fluctuations provided in this embodiment of the invention includes the following steps: S1 to S11.

[0077] S1: Acquire urban land parcel data, road network data, spatial isolation data, and real-time population data of land parcels at multiple consecutive time points within the target area, and preprocess the urban land parcel data and road network data;

[0078] S2: Based on the processed urban land parcel data, conduct spatial analysis and establish an adjacency matrix between urban land parcels;

[0079] S3: Obtain vector data of open spaces within the target area, screen potential emergency shelters, integrate relevant information into urban land parcel data, and export urban land parcel information table;

[0080] Among these, the relevant information refers to: the location (land parcel) of potential emergency shelters and their effective shelter area.

[0081] S4: Utilize the processed urban plot data and road network data to conduct network analysis, establish a network distance matrix between urban plots, and reclassify the network distances to obtain a spatial relationship matrix between potential emergency shelters and urban plots.

[0082] Among them, reclassifying network distance means reclassifying the numerical values ​​of elements in the network distance matrix. S5: Construct the coverage plot vector for each potential emergency shelter, and use an exhaustive method to solve for the minimum number of potential emergency shelters that can cover the entire target area, as well as all possible combinations of potential emergency shelters;

[0083] Among them, the potential emergency shelter combination scheme is a feasible scheme composed of potential emergency shelter combinations, which is a technical term in this field, and will not be described in detail in the embodiments of this invention.

[0084] S6: Select any one of the potential emergency shelter combinations and generate an initial responsibility zone division scheme based on the nearest neighbor principle;

[0085] S7: Calculate the population fluctuation coefficient of the previous responsibility area division scheme based on the real-time population data of the plots at each time point;

[0086] In the first iteration, the previous responsibility area division scheme in step S7 is the initial responsibility area division scheme in step S6, and in subsequent iterations, it is always the previous responsibility area division scheme.

[0087] S8: Based on the adjacency matrix between urban plots and the spatial relationship matrix between potential emergency shelters and urban plots, find the exchangeable plots corresponding to each responsibility area, and randomly select one urban plot from the exchangeable plots to exchange as a new responsibility area division scheme.

[0088] S9: Repeat steps S7-S8 until all responsibility zone division schemes and corresponding population fluctuation coefficients are obtained under a potential emergency shelter combination scheme.

[0089] S10: Repeat steps S6-S9 to obtain all responsibility area division schemes and corresponding population fluctuation coefficients under all potential emergency shelter combination schemes, and select several responsibility area division schemes that are close to the minimum population fluctuation coefficient as the preferred schemes.

[0090] S11: Calculate the effective refuge area gap for each preferred scheme, select the preferred scheme with the smallest effective refuge area gap as the optimal scheme, and output the potential emergency refuge site combination scheme and responsibility area division scheme in the optimal scheme; based on the final results, carry out emergency refuge site selection and responsibility area division to cope with emergency refuge needs under population fluctuation conditions.

[0091] In summary, the embodiments of the present invention optimize the selection of emergency shelter sites, the division of responsibility areas, and the allocation of space capacity through the above steps S1-S11, automatically generating optimized schemes for the selection of emergency shelter sites and the division of responsibility areas, thereby improving the success rate of emergency shelters, reducing the loss of personnel and property, and meeting the needs of emergency shelters in real life.

[0092] Example 2

[0093] The following is combined Figure 2 and Figure 3 The implementation methods of steps S1 to S11 will be described in detail.

[0094] In one possible implementation, step S1 includes:

[0095] S101: Acquire urban land parcel data, road network data, spatial isolation data, and real-time population data of land parcels at multiple consecutive time points within the target area;

[0096] The urban land parcel data includes polygon vector graphics and a land parcel ID field; the road network data consists of road network vector data drawn in single-line form and a road ID field; the spatial isolation data consists of spatial isolation element data drawn in single-line form, including rivers, railways, major urban roads, etc.; the real-time population data for land parcels has a time node interval of 1 hour, with no less than 120 time nodes, presented in tabular form, including fields such as land parcel ID, time node, and population.

[0097] S102: Use road network data to preprocess urban plot data, extend the boundaries of urban plots facing the street to the center line of nearby roads, and retain the original plot IDs to obtain the first urban plot data;

[0098] See Figure 2 In the preprocessed urban land parcel data, the wide white area in the middle represents road land, the line in the middle of the road is the road centerline, and the numbered parcels are urban land parcels, for example: Figure 2 The data includes urban plots 01-17, with the wide white area between urban plots 02 and 03 representing road land. In this embodiment of the invention, the boundaries of the adjacent urban plots are extended to the nearby road centerlines during processing, effectively removing the wide white area. The centerlines of each road are then connected to obtain the processed urban plot data, which serves as the first urban plot data in this embodiment of the invention.

[0099] S103: Using spatial isolation data, preprocess the road network data, convert the main urban roads that serve as spatial isolation elements into parallel double-line roads, and disconnect the roads where other spatial isolation elements are located to obtain the first road network data.

[0100] See Figure 3 In this embodiment of the invention, the main urban roads that serve as spatial isolation elements are converted from single-line roads to parallel double-line roads, and roads at the locations of other spatial isolation elements such as railways and rivers are disconnected to obtain the processed graphics, which serve as the first road network data of this embodiment of the invention.

[0101] Step S2 includes:

[0102] S201: Using ArcGIS's "Polygon Neighbors" tool, input the first city's land parcel data, select "Plot ID" in the Report By Field section, check "Include both sides of neighbor relationship", and output the adjacency table;

[0103] S202: Construct an adjacency matrix between urban land parcels based on the adjacency table. The row and column numbers are the land parcel IDs of the urban land parcels. The adjacency value (corresponding element in the matrix) is 1 or 0, representing "adjacent" and "not adjacent" respectively, which can be expressed as formula (1).

[0104]

[0105] Where, N k This is the adjacency matrix between urban plots; k is the number of urban plots within the target area; n ij The adjacency value is the adjacency value between urban plot i and urban plot j, which can be extracted from the adjacency table. If they are adjacent, the value is 1, and if they are not adjacent, the value is 0. In practice, this can be achieved by using a combination of functions such as IFERROR, INDEX, and FILTER in Excel editing tools, or by using Python tool libraries. This embodiment of the invention does not limit this.

[0106] Step S3 includes:

[0107] S301: Obtain vector data of open space within the target area (a technical term in this field), use ArcGIS's "Add Geometry Attributes" tool to add an area attribute to the open space vector data, rename the generated POLY_AREA (polygon area) field to "Effective Refuge Area", and obtain the data of the first potential emergency refuge site;

[0108] Among them, the open space vector data covers all open space elements within the research scope. The data includes area vector graphics as well as fields such as site name, function type, elevation, and slope. This embodiment of the invention will not elaborate on these aspects.

[0109] S302: From the data of the first potential emergency shelter, according to the principles of functional type (park green space, open square, ground parking lot, or school playground), size not less than 2000㎡, elevation higher than the average elevation of the target area, and slope less than 7%, filter elements and export them to obtain the data of the second potential emergency shelter.

[0110] The aforementioned screening principles are formulated with reference to the national standard "Classification and Grading of Emergency Shelters" (GB / T44013-2024), and can be adjusted according to local standards and specific circumstances. This embodiment of the invention does not limit these principles.

[0111] S303: Using ArcGIS's "Spatial Join" tool, select the first city parcel data as the target features, select the second potential emergency shelter data as the join features, select "JOIN ONE TO ONE" for the join operation, check "Keep All Target Features", select "Effective Shelter Area" for the field map of join features, and select "CONTAINS" for the match option. This will integrate the second potential emergency shelter information into the first city parcel data, resulting in the second city parcel data. Then, export the attribute table of the second city parcel data as a city parcel information table.

[0112] In the urban land parcel information table, if a potential emergency shelter exists on an urban land parcel element, then the effective shelter area field value of that urban land parcel element is equal to the effective shelter area of ​​the potential emergency shelter in the urban land parcel; if no potential emergency shelter exists on an urban land parcel element, then the effective shelter area field value of that urban land parcel element is null.

[0113] Step S4 includes:

[0114] S401: Create a new file geodatabase, create a new feature dataset "Road Topology" in it, select a suitable coordinate system, and import the first road network data into the road topology feature dataset; create a new topology in the road topology feature dataset, select the road network data, add rules "No overlap (lines)", "No hanging points (lines)", and "No pseudo nodes (lines)" to generate the second road network data.

[0115] S402: Using ArcGIS's "Create Network Dataset" tool, input the second road network data, select "No Elevation" for the elevation model, and obtain the third road network data;

[0116] S403: Use ArcGIS's "Feature to point" tool to input the second city plot data and obtain the city plot center point data;

[0117] Among them, the city plot center point data is a point-like vector layer, where each feature corresponds to the center point of a city plot feature and inherits the plot ID field of the second city plot.

[0118] S404: Use ArcGIS's "Make OD Cost Matrix Analysis Layer" tool, select the third road network data as the network data source, generate an OD (origin-destination) cost matrix containing six layers: origin, destination, line, point obstacle, line obstacle, and area obstacle. Input the city parcel center point data as origins and destinations respectively, run network analysis to obtain a new line layer, and export its attribute table as a city parcel center point network distance table;

[0119] The new line layer represents the shortest path between the center points of urban plots. Its attribute table includes fields such as Name and Total_Length. The Name field indicates the start and end points of the path, presented in the form of "starting plot ID - destination plot ID". The Total_Length field indicates the path length.

[0120] S405: Construct a network distance matrix between urban plots based on the network distance table of urban plot center points. The row number is the plot ID of the urban plot, and the column number is the plot ID of the potential emergency shelter. It can be expressed as formula (2).

[0121]

[0122] in, This is the network distance matrix between potential emergency shelters and urban plots; k is the number of urban plots within the target area; m is the number of potential emergency shelters; s i It is the plot ID of the potential emergency shelter, which is the same as the plot ID of the plot in the city, i.e., s i ∈{1,2,k}; It is a potential emergency shelter. i The network distance between the city plot j and the city plot center point network distance table can be extracted. In practice, it can be achieved by using a combination of functions such as IFERROR, INDEX, and FILTER in Excel editing tools, or by using Python tool libraries. This embodiment of the invention does not limit the specific implementation.

[0123] S406: Using 300m and 1000m as thresholds, the network distance between potential emergency shelters and urban plots is reclassified into three categories: very close, adjacent, and not adjacent, represented by 2, 1, and 0 respectively, to obtain the spatial relationship matrix between potential emergency shelters and urban plots, which can be expressed as formula (3).

[0124]

[0125] in, This is a spatial relationship matrix between potential emergency shelters and urban land parcels; k is the number of urban land parcels within the target area; m is the number of potential emergency shelters; s i It is the plot ID of the potential emergency shelter, which is the same as the plot ID of the plot in the city, i.e., s i ∈{1,2,k}; It is a potential emergency shelter. i The spatial relationship index between urban plot j and urban plot j is determined based on the network distance between the two urban plots: if (Very close), then like (Neighboring) then r ij =1; if (Not adjacent)

[0126] The 1000m threshold is determined with reference to the national standard "Classification and Delineation of Emergency Shelters" (GB / T44013-2024), while the 300m threshold is formulated based on residents' behavioral habits and can be adjusted according to local standards and specific circumstances. This embodiment of the invention does not limit this.

[0127] Step S5 includes:

[0128] S501: In the urban land information table, filter the land IDs that have potential emergency shelters, that is, land IDs whose effective shelter area field value is not empty. Extract the corresponding column from the spatial relationship matrix between potential emergency shelters and urban land to obtain the vector of land covered by potential emergency shelters, which can be expressed as formula (4).

[0129]

[0130] in, The plot ID is s i The vector of potential emergency shelter coverage areas; k is the number of urban plots within the target area; s i It is the plot ID of the potential emergency shelter, which is the same as the plot ID of the plot in the city, i.e., s i ∈{1,2,k}; It is a potential emergency shelter. i Spatial relationship indicators between all urban plots; this step can be implemented using computer programming, but this embodiment of the invention does not limit this.

[0131] S502: From all potential emergency shelter coverage plot vectors, randomly select i plots and add them together. Iterate through all possibilities and check whether all elements of the new vector obtained by addition are non-zero. i starts from 1 and increases sequentially while checking. If the above condition is not met, increase the number of selections until the above condition is met. At this time, output the number of selections as the planned number of emergency shelters, and all combinations of potential emergency shelter coverage plot vectors that meet the conditions.

[0132] The number of samples drawn when the aforementioned conditions are met is the minimum number of potential emergency shelters covering the entire target area. For ease of management, this number is used as the planned number of emergency shelters. This step can be implemented using computer programming, but this embodiment of the invention does not limit this.

[0133] S503: Convert all combinations of potential emergency shelter coverage plot vectors that meet the conditions into a set of plot IDs, and save the set as a text file "Potential Emergency Shelter Combination Scheme".

[0134] For example: F1, F3, F5, and F7 are a set of potential emergency shelter coverage plot vectors that meet the conditions, which can be converted into a set of potential emergency shelter combination schemes as {1, 3, 5, 7}; F1, F4, F6, and F8 are a set of potential emergency shelter coverage plot vectors that meet the conditions, which can be converted into a set of potential emergency shelter combination schemes as {1, 4, 6, 8}; this step can be implemented using computer programming.

[0135] Step S6 includes:

[0136] S601: Select one scheme from the potential emergency shelter combination schemes, construct a set of urban plots for each potential emergency shelter responsibility area included in the scheme, and write the plot ID of the potential emergency shelter into the corresponding urban plot set;

[0137] S602: In the adjacency matrix, search for urban plots that are adjacent to any element in the set of urban plots in the current potential emergency shelter responsibility area (adjacency value = 1); in the network distance matrix, find the minimum network distance between these urban plots and the potential emergency shelters corresponding to the adjacent elements, and add the plot ID of each urban plot to the set of urban plots in the corresponding potential emergency shelter responsibility area.

[0138] S603: Repeat step S602 until all urban plots are assigned to the urban plot set of potential emergency shelter responsibility areas, obtain the initial responsibility area division scheme, and save the urban plot set of the initial responsibility area division scheme as a text file.

[0139] If urban plots 1, 2, 4, 5, and 9 are assigned to potential emergency shelter 5, then in the text file it would be written as: Potential Emergency Shelter 5: {1, 2, 4, 5, 9}.

[0140] Steps S601, S602, and S603 can be implemented using computer programming and iterative algorithms, and this embodiment of the invention does not limit this.

[0141] Step S7 includes:

[0142] S701: According to the previous responsibility area division scheme, the real-time population data of each plot at each time point is summarized to obtain the real-time population of the responsibility area at multiple consecutive time points.

[0143] S702: Calculate the population mean and standard deviation of each responsibility area at all time points, and then calculate the population fluctuation coefficient of each responsibility area. For specific calculation methods, please refer to formulas (5)-(7).

[0144]

[0145]

[0146] Among them, P i μ represents the real-time population of the responsibility area s at different time points; t represents the number of time points; μ s σ is the average population of the responsibility area s at all time points; s C represents the population standard deviation of the responsibility area s at all time points; s denoted as the population fluctuation coefficient for the area of ​​responsibility s.

[0147] S703: Sum the population fluctuation coefficients of all responsibility areas to obtain the population fluctuation coefficient of the responsibility area division scheme.

[0148] Step S8 includes:

[0149] S801: Based on the adjacency matrix between urban plots, find the adjacent plots of each responsibility area in the previous responsibility area division scheme, and represent them in the form of multiple sets. Remove elements that have only one indirectly adjacent plot (adjacent plot of adjacent plot) in the corresponding responsibility area; based on the spatial relationship matrix between potential emergency shelters and urban plots, remove urban plots with a spatial relationship index of 2 (very close spatial relationship) with any potential emergency shelter, and obtain the set of exchangeable plots corresponding to each responsibility area;

[0150] S802: Randomly select one plot from the set of exchangeable plots and exchange it to the corresponding responsibility area, generate a new responsibility area division scheme, and save the set of urban plots with the new responsibility area division scheme as a text file;

[0151] Step S9 includes: repeating steps S7-S8 until all responsibility area division schemes and corresponding population fluctuation coefficients are obtained under a potential emergency shelter combination scheme.

[0152] Step S10 includes:

[0153] S1001: Repeat steps S6-S9 to obtain all responsibility area division schemes and corresponding population fluctuation coefficients under all potential emergency shelter combination schemes;

[0154] S1002: Sort all responsibility area division schemes according to the population fluctuation coefficient, select responsibility area division schemes that differ from the minimum population fluctuation coefficient by less than 0.5%, and select the corresponding potential emergency shelter combination scheme and responsibility area division scheme as the preferred scheme.

[0155] The 0.5% threshold is a reference value in this embodiment of the invention, and this embodiment of the invention does not limit it.

[0156] Step S11 includes:

[0157] S1101: Based on the responsibility area division scheme in the preferred scheme and the real-time population data of the plots at all time points, calculate the average population of each responsibility area in each preferred scheme at all time points.

[0158] S1102: Based on the per capita effective refuge area index specified in the relevant standards and the average population of each responsibility area in each preferred scheme at all time points, calculate the ideal effective refuge area of ​​each responsibility area in each preferred scheme. For the specific calculation method, please refer to formula (8).

[0159]

[0160] in, It is the ideal effective refuge area of ​​the j-th responsibility area in the i-th preferred scheme; α is the average population of the j-th responsibility area in the i-th preferred scheme at all time points; α is the per capita effective refuge area index specified by relevant standards. In this embodiment of the invention, the national standard "Classification and Classification of Emergency Shelters" (GB / T44013-2024) adopts 1.5㎡ / person, but this embodiment of the invention does not limit it.

[0161] S1103: Using the ideal effective refuge area of ​​each responsibility area in each preferred scheme and the effective refuge area of ​​the corresponding potential emergency refuge sites in the urban land information table, calculate the effective refuge area gap of each preferred scheme. For the specific calculation method, please refer to formula (9).

[0162]

[0163] Among them, L i is the effective refuge area gap of the i-th preferred scheme; u is the number of planned emergency refuge sites (from step S502); It is the ideal effective refuge area of ​​the j-th responsibility area in the i-th preferred scheme; It is the effective refuge area of ​​the potential emergency refuge site corresponding to the j-th responsibility area in the i-th preferred scheme, which can be obtained from the urban land information table.

[0164] S1104: Select the optimal solution with the smallest effective refuge area gap as the best solution, and output the potential emergency refuge combination scheme and responsibility area division scheme in the scheme; based on the final results, carry out emergency refuge site selection and responsibility area division to meet the emergency refuge needs under population fluctuation conditions.

[0165] In summary, under the constraints of regulatory requirements, practical conditions, management methods, and behavioral habits, this embodiment of the invention aims to reduce population fluctuations and ensure capacity matching. It utilizes computers to generate all reasonable solutions and conducts correlation optimization of emergency shelter site selection, responsibility area division, and spatial capacity allocation. It can automatically generate optimized solutions for emergency shelter site selection and responsibility area division, and the resulting optimized solutions significantly improve the effectiveness of responding to population fluctuations.

[0166] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0167] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for selecting emergency shelter sites and delineating responsibility zones in response to population fluctuations, characterized in that, The method includes the following steps: ① Conduct spatial analysis based on the processed urban land parcel data and establish an adjacency matrix between urban land parcels; ② Based on the open space vector data of the target area, potential emergency shelters are screened, and relevant information is integrated into the urban plot data to export the urban plot information table; among them, the open space vector data includes areal vector graphics as well as fields such as site name, function type, elevation, and slope. ③ Based on the processed urban plot data and processed road network data, network analysis is carried out to establish a network distance matrix between urban plots and to reclassify the network distances to obtain a spatial relationship matrix between potential emergency shelters and urban plots; where the network distance matrix is ​​used to represent the actual distance between multiple urban plots based on the urban pedestrian network. ④ Construct the coverage plot vector for each potential emergency shelter, and use an exhaustive method to solve for the minimum number of potential emergency shelters covering the entire target area, as well as all possible combinations of potential emergency shelters; wherein, in the urban plot information table, the plot IDs with potential emergency shelters are filtered, and the corresponding columns are extracted from the spatial relationship matrix between potential emergency shelters and urban plots to obtain the coverage plot vector of potential emergency shelters; ⑤ Select any one of the potential emergency shelter combinations and generate an initial responsibility zone division scheme based on the nearest neighbor principle; ⑥ Calculate the population fluctuation coefficient of the previous responsibility area division scheme based on the real-time population data of each plot at each time point; ⑦ Based on the adjacency matrix between urban plots and the spatial relationship matrix between potential emergency shelters and urban plots, find the exchangeable plots corresponding to each responsibility area, and randomly select one urban plot from the exchangeable plots to exchange as a new responsibility area division scheme. ⑧ Repeat steps ⑥-⑦ until all responsibility zone division schemes and corresponding population fluctuation coefficients are obtained under a potential emergency shelter combination scheme; ⑨ Repeat steps ⑤-⑧ to obtain all responsibility area division schemes and corresponding population fluctuation coefficients under all potential emergency shelter combination schemes. Select several responsibility area division schemes that are close to the minimum population fluctuation coefficient as the preferred schemes. ⑩ Calculate the effective refuge area gap for each preferred option, select the preferred option with the smallest effective refuge area gap as the optimal option, and output the potential emergency refuge site combination scheme and responsibility area division scheme in the optimal scheme; based on the final results, carry out emergency refuge site selection and responsibility area division to cope with emergency refuge needs under population fluctuation conditions.

2. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The processed urban land parcel data and the processed road network data are as follows: Acquire urban land parcel data, road network data, and spatial isolation data within the target area; The urban land parcel data is preprocessed using road network data. The boundaries of the urban land parcels facing the street are extended to the center line of the nearby road, while the original parcel IDs are retained. The resulting first urban land parcel data is the processed urban land parcel data. By utilizing spatial isolation data, the road network data is preprocessed. The main urban roads that serve as spatial isolation elements are converted from single-line to parallel double-line roads, and the roads at the locations of other spatial isolation elements are disconnected. The resulting first road network data is the processed road network data.

3. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 2, characterized in that, The spatial analysis based on the processed urban land parcel data establishes an adjacency matrix between urban land parcels as follows: Using ArcGIS's Area Neighborhood tool, input the first city's land parcel data, select the parcel ID in the field report, check "Include both sides of the neighborhood relationship", and output the adjacency table; Construct an adjacency matrix between urban land parcels based on the adjacency table. The row and column numbers are the land parcel IDs, and the adjacency value is 1 or 0, representing "adjacent" and "not adjacent" respectively.

4. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The open space vector data based on the target area is used to screen potential emergency shelters, and the relevant information is integrated into the urban land parcel data to derive the urban land parcel information table as follows: Obtain open space vector data of the target area, use ArcGIS's Add Geometry Attribute tool to add area attributes to the open space vector data, rename the generated polygon area field to "Effective Refuge Area" to obtain the data of the first potential emergency refuge site; From the data of the first potential emergency shelter, elements are selected and exported according to the preset principles of functional type, scale, elevation, and slope to obtain the data of the second potential emergency shelter. Using ArcGIS's spatial connection tool, select the first city plot data as the target feature, select the second potential emergency shelter data as the connection feature, select one-to-one connection for the connection operation, check "keep all target features", select "effective shelter area" for the field mapping of the connection feature, and select "include" for the matching option. This will integrate the information of the second potential emergency shelter into the first city plot data, resulting in the second city plot data. Then, export the attribute table of the second city plot data as a city plot information table.

5. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The network analysis is conducted based on the processed urban plot data and road network data to establish a network distance matrix between urban plots. The network distances are then reclassified to obtain the spatial relationship matrix between potential emergency shelters and urban plots: Using ArcGIS's feature conversion tool, input the second city plot data to obtain the city plot center point data; Using ArcGIS's Create OD Cost Matrix Analysis Layer tool, select the third road network data as the network data source to generate a start-destination cost matrix containing six layers: start point, destination point, line, point obstacle, line obstacle, and area obstacle. Input the city parcel center point data as the start point and destination point respectively, run network analysis to obtain a new line layer, and export its attribute table as the city parcel center point network distance table. Construct a network distance matrix between urban plots based on the network distance table of urban plot center points, where the row number is the plot ID of the urban plot and the column number is the plot ID of the potential emergency shelter. Based on the threshold, the network distance between potential emergency shelters and urban plots is reclassified into three categories: very close, adjacent, and not adjacent, represented by 2, 1, and 0 respectively, to obtain the spatial relationship matrix between potential emergency shelters and urban plots.

6. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The process involves constructing the coverage vector for each potential emergency shelter, using an exhaustive method to determine the minimum number of potential emergency shelters covering the entire target area, and identifying all possible combinations of potential emergency shelters: From all potential emergency shelter coverage area vectors, randomly select i and add them together. Iterate through all possibilities and check whether all elements of the new vector obtained by addition are non-zero. i starts from 1 and increases sequentially and checks. If the above condition is not met, increase the number of selections until the above condition is met. At this time, output the number of selections as the planned number of emergency shelters, as well as all combinations of potential emergency shelter coverage area vectors that meet the conditions. Convert all combinations of potential emergency shelter coverage plot vectors that meet the conditions into a set of plot IDs, and save the set as a text file "Potential Emergency Shelter Combination Scheme".

7. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The step of arbitrarily selecting one scheme from all potential emergency shelter combinations and generating an initial responsibility zone division scheme based on the nearest neighbor principle is as follows: Select one scheme from the potential emergency shelter combination schemes, construct a set of urban plots for each potential emergency shelter responsibility area included in the scheme, and write the plot ID of the potential emergency shelter into the corresponding urban plot set; In the adjacency matrix, search for urban plots that are adjacent to any element in the set of urban plots in the current potential emergency shelter responsibility area; In the network distance matrix, find the minimum network distance between these urban plots and the potential emergency shelters corresponding to adjacent elements, and add the plot ID of each urban plot to the urban plot set of the corresponding potential emergency shelter responsibility area; Repeat the above steps until all urban plots have been assigned to the set of urban plots within the potential emergency shelter responsibility area, thus obtaining the initial responsibility area division scheme. Save the set of urban plots with the initial responsibility area division scheme as a text file.

8. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, Based on the real-time population data of each land parcel at each time point, the population fluctuation coefficient of the previous responsibility area division scheme is calculated as follows: Acquire real-time population data of plots at multiple consecutive time points, and summarize the real-time population data of plots at each time point according to the previous responsibility area division scheme to obtain the real-time population of responsibility areas at multiple consecutive time points. The population mean and standard deviation of each responsibility area at all time points are statistically analyzed, and then the population fluctuation coefficient of each responsibility area is calculated. The population fluctuation coefficients of all responsibility areas are added together to obtain the population fluctuation coefficient of the responsibility area division scheme.

9. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 5, characterized in that, The method involves identifying exchangeable plots for each responsibility area based on the adjacency matrix between urban plots and the spatial relationship matrix between potential emergency shelters and urban plots. One urban plot is then randomly selected from these exchangeable plots for exchange, forming a new responsibility area delineation scheme. Based on the adjacency matrix between urban plots, find the adjacent plots of each responsibility area in the previous responsibility area division scheme, and represent them in the form of multiple sets. Eliminate elements that have only one indirectly adjacent plot in the corresponding responsibility area. Based on the spatial relationship matrix between potential emergency shelters and urban plots, eliminate urban plots with a spatial relationship index of 2 with any potential emergency shelter, and obtain the set of exchangeable plots corresponding to each responsibility area. Randomly select one plot from the set of exchangeable plots and exchange it to the corresponding responsibility area to generate a new responsibility area division scheme. Save the set of urban plots with the new responsibility area division scheme as a text file.

10. The method for selecting emergency shelter sites and delineating responsibility areas in response to population fluctuations according to claim 1, characterized in that, The effective refuge area gap for each preferred scheme is statistically analyzed, and the preferred scheme with the smallest effective refuge area gap is selected as the optimal scheme. The potential emergency refuge site combination scheme and responsibility area division scheme in the optimal scheme are output as follows: Based on the responsibility area division scheme in the preferred scheme and the real-time population data of the plots at all time points, the average population of each responsibility area in each preferred scheme at all time points is calculated. Based on the per capita effective refuge area index stipulated in relevant standards, and the average population of each responsibility area in each preferred scheme at all time points, calculate the ideal effective refuge area of ​​each responsibility area in each preferred scheme. Using the ideal effective refuge area of ​​each responsibility area in each preferred scheme and the effective refuge area of ​​the corresponding potential emergency refuge sites in the urban land information table, calculate the effective refuge area gap of each preferred scheme; The optimal solution is selected based on the smallest gap in effective refuge area. The solution is then output as the combination of potential emergency refuge sites and the division of responsibility areas within that solution.

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