An evaluation method for the restriction of complex terrain on the transportation of mountain residents

Abstract

The present invention discloses an evaluation method for the restriction of complex terrain on the transportation of mountain residents, which includes the following steps: First, calculate the distances between different residential areas in the mountainous area and generate spatial connection lines between each residential area and its neighboring residential areas; Second, overlay the spatial connection lines with the digital elevation model, extract the elevation values of the areas passed by different spatial connection lines, and form an elevation sequence; Third, calculate the numerical characteristics of each elevation sequence, including the average value, standard deviation, maximum value, and minimum value; Fourth, calculate the attribute space elevation variation ratio and the geographical space elevation variation ratio corresponding to each elevation sequence, and further calculate the restriction index; Fifth, average the restriction indices of all elevation sequences corresponding to the same residential area as the traffic restriction evaluation value of the current residential area. The present invention focuses on the transportation between residential areas in mountain villages with complex terrain, and with the help of a high-precision digital elevation model, realizes the measurement and evaluation of the restriction of complex terrain in the mountainous area on the transportation between villages. Empirical evidence shows that the method can realize the quantitative measurement and evaluation of traffic restriction by complex terrain based on the elevation sequences extracted from the spatial connection lines between different villages. The present invention provides a relatively intuitive and accurate evaluation method for the restriction of terrain on the transportation of mountain residents for aspects such as the development of traffic accessibility, logistics distribution, new rural construction, urban-rural integration, and regional traffic planning in mountainous areas.

Description

Technical Field

[0001] The present invention relates to the fields of geographic information technology, digital terrain analysis, etc., and particularly relates to an evaluation method for the restriction of complex terrain on the traffic travel of mountain residents. Background Art

[0002] Mountainous regions have complex terrains, characterized by drastic surface undulations and steep slopes, which affect the spatial differentiation laws of different geographical elements. In China, a large number of rural residents live in mountainous regions, and the drastic changes in terrain elevation in mountainous areas will have an obvious restrictive effect on the daily traffic travel of residents.

[0003] With the development of digital mapping technology and information sharing technology in the fields of geographic information science and remote sensing science, based on high-resolution remote sensing image data, using algorithms such as object recognition and supervised classification, human settlement aggregation areas can be accurately identified and extracted, including the settlements in mountainous areas. At the same time, open-source geographic information technology enables the public access to the spatial distribution data of these settlements, providing data support for analyzing the traffic travel of mountain residents. On the other hand, using ground observation technologies and platforms such as oblique photogrammetry and lidar, Digital Elevation Model (DEM) data can be quickly produced, realizing the digital description and expression of the terrain distribution in a large area. DEM data has been widely used in various geoscience analyses, such as terrain feature extraction, soil distribution simulation, hydrological process simulation, etc. Therefore, based on the spatial distribution data of mountain settlements and DEM data, the evaluation and analysis of the restriction of terrain on the traffic travel of mountain residents can be realized, and thus provide a basis for mountain rural traffic planning and rural development. Summary of the Invention

[0004] The present invention focuses on the restrictive impact of drastic elevation changes in mountain terrains on the daily traffic travel of residents, and provides an evaluation method for the restriction of complex terrain on the traffic travel of mountain residents. The technical problems to be solved include the measurement and evaluation of the restriction of terrain on traffic.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] An evaluation method for the restriction of complex terrain on the traffic travel of mountain residents includes five parts: calculation of the distance between settlements and generation of spatial connections, superposition of spatial connections and extraction of high-order sequences, calculation of numerical features of high-order sequences, calculation of terrain restriction indexes, and calculation of evaluation scores for traffic travel restrictions.

[0007] Calculation of the distance between settlements and generation of spatial connections, the steps of this part are as follows:

[0008] S1: Calculate the distances between a settlement and all other settlements within the region;

[0009] S2: Select the top several settlement points with the smallest distances as neighboring settlement points, and generate different spatial connections from the settlement points to the neighboring settlement points;

[0010] S3: Calculate the Euclidean distance lengths of different spatial connections in the projected coordinate system;

[0011] Spatial connection overlay and high - order sequence extraction, the steps are as follows:

[0012] S4: Perform spatial overlay on the spatial connection data and the digital elevation model data;

[0013] S5: On the spatial connection, generate spatial point features arranged at equal - distance intervals with the pixel size of the digital elevation model as the interval;

[0014] S6: Extract the numerical values of the digital elevation model data at each spatial point to extract the high - order sequence;

[0015] Calculation of numerical characteristics of the high - order sequence, the steps are as follows:

[0016] S7: Calculate the average value, standard deviation, maximum value, and minimum value of all elevation numerical values in the high - order sequence;

[0017] Calculation of the terrain restriction index, the steps are as follows:

[0018] S8: Calculate the difference between the maximum value and the minimum value of the high - order sequence, and further calculate the ratio of the difference to the distance between the corresponding settlement points of the high - order sequence, which is called the elevation variation ratio of the geospatial;

[0019] S9: Calculate the ratio of the standard deviation to the average value of the high - order sequence, which is called the elevation variation ratio of the attribute space;

[0020] S10: Calculate the product of the elevation variation ratio of the geospatial and the elevation variation ratio of the attribute space as the restriction index of the current high - order sequence;

[0021] Calculation of the traffic travel restriction evaluation score, the steps are as follows:

[0022] S11: Summarize the restriction indices of all high - order sequences between the settlement points and the neighboring settlement points, and calculate the average value of multiple restriction indices as the evaluation score of the traffic travel restriction of the settlement points. Description of the drawings

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only schematic diagrams of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0024] Figure 1 Technical flow chart of the invention;

[0025] Figure 2 DEM and distribution map of residential areas provided by the present invention;

[0026] Figure 3 Spatial connection diagram between different residential areas provided by the present invention;

[0027] Figure 4 High - order sequence diagram between residential areas provided by the present invention;

[0028] Figure 5 Evaluation result map of traffic travel restrictions between residential areas provided by the present invention; Detailed implementation manners

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0030] The following is the part of distance calculation between residential areas and generation of spatial connection lines:

[0031] Step 1: According to the spatial boundary of the evaluation range, collect the DEM data and residential area data within the corresponding range, set the two types of data in the same projection coordinate system, and achieve spatial matching.

[0032] Step 2: Based on the spatial data of residential areas, calculate the spatial distance from each residential area to all other residential areas respectively. The calculation method of the spatial distance is as follows:

[0033]

[0034] Wherein, X o and Y o are the projection coordinate values corresponding to the longitude and latitude of residential area o, and X d and Y d are the projection coordinate values corresponding to the longitude and latitude of residential area d.

[0035] Step 3: Screen out the other k nearest settlements for each settlement, and respectively generate the spatial connection lines between the current settlement and the k nearest settlements to obtain k vector line features.

[0036] The following is the part of spatial connection line superposition and high program sequence extraction:

[0037] Step 1: Perform spatial superposition on the spatial connection lines between different settlements and the DEM data. According to the spatial resolution size h of the DEM data, generate the sequentially arranged points P = {p i |0 < i < N} at a fixed interval distance of h on the spatial connection line.

[0038] Step 2: Extract the elevation values corresponding to the positions of each point p i , and generate the high program sequence S o,d according to the interval order of the points, indicating the high program sequence from settlement o to settlement d.

[0039] The following is the part of high program sequence numerical feature calculation:

[0040] Step 1: Screen the maximum value Max o,d and the minimum value Min o,d of the elevation of the high program sequence S o,d , and calculate the range. The calculation formula is:

[0041] Range o,d = Max o,d - Min o,d

[0042] Step 2: Calculate the average value Mean o,d of the data of the high program sequence S o,d . The calculation formula is as follows:

[0043]

[0044] Among them represents the i-th value in the high program sequence from settlement o to settlement d, and N represents the number of numerical values in the high program sequence.

[0045] Step 3: Calculate the standard deviation SD o,d of the data of the high program sequence S o,d . The calculation formula is as follows:

[0046]

[0047] Among them represents the i-th value in the high program sequence from settlement o to settlement d, and N represents the number of numerical values in the high program sequence.

[0048] The following is the calculation part of the terrain restriction index:

[0049] Step 1: Calculate the geographical spatial elevation variation ratio from settlement o to settlement d. The calculation formula is as follows:

[0050]

[0051] Step 2: Calculate the attribute spatial elevation variation ratio from settlement o to settlement d. The calculation formula is as follows:

[0052]

[0053] Step 3: Calculate the terrain restriction index from settlement o to settlement d. The calculation formula is as follows:

[0054] RI o,d =GR o,d ×FR o,d

[0055] The following is the calculation part of the comprehensive score of traffic travel restriction:

[0056] Step 1: According to the terrain restriction index from settlement o to its k adjacent settlements d j (1≤j≤k), calculate the average value of all restriction indices as the comprehensive score of traffic travel restriction of settlement o, which is used to measure the terrain restriction suffered by the traffic travel of settlement o.

[0057] Finally, 117 village settlements under the jurisdiction of 13 townships in the northwest of Qingyang, Gansu Province, located in the middle of the Loess Plateau, were selected as the experimental objects. The spatial resolution of the DEM data was selected as 30m×30m, and the number of adjacent settlements k = 5 was set. The method of this patent was used to measure the restriction of complex terrain on the traffic travel of mountain residents. The elevation, spatial boundary, and settlement distribution of the experimental objects and other results are as Figure 2 shown, the spatial connection results of the experimental object settlements and their adjacent settlements are as Figure 3 shown, the elevation sequence from the settlement numbered JMD-99 in the experimental object to its k (k = 5) adjacent settlements is as Figure 4 shown, and the final comprehensive score results of the terrain restriction of all settlements of the experimental object are as Figure 5 shown.

[0058] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined by this solution can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this solution, but rather should conform to the broadest scope consistent with the principles and novel features disclosed by the present invention.

Claims

1. A method for evaluating the restrictiveness of complex terrain on the transportation of mountain residents, including five parts: distance calculation between settlements and spatial line generation, spatial line superposition and elevation sequence extraction, elevation sequence numerical feature calculation, terrain restrictiveness index calculation, and transportation restrictiveness evaluation score calculation: The steps for calculating the distance between settlements and generating spatial lines are as follows: S1: Calculate the distance between the settlement and all other settlements in the area; S2: Select the first several settlements with the shortest distance as neighboring settlements, and generate different spatial connection lines from settlements to neighboring settlements; S3: Calculate the Euclidean distance length of different spatial lines in the projected coordinate system; Spatial line superposition and high-order sequence extraction, the steps of this part are as follows: S4: spatially superimpose the spatial connection data and the digital elevation model data; S5: Generate spatial point features arranged at equal intervals on the spatial connection line with the pixel size of the digital elevation model as the interval; S6: extracting the value of the digital elevation model data at each spatial point and extracting the elevation sequence; The numerical feature calculation of the high-level sequence, the steps of this part are as follows: S7: Calculate the mean, standard deviation, maximum and minimum values ​​of all elevation values ​​in the elevation sequence; Terrain restrictiveness index calculation, the steps are as follows: S8: Calculate the difference between the maximum and minimum values ​​of the elevation sequence, and further calculate the ratio of the difference to the distance between the corresponding settlements in the elevation sequence, which is called the elevation variation ratio of the geographic space; S9: Calculate the ratio between the standard deviation and the mean value of the elevation series, which is called the elevation variation ratio in the attribute space; S10: Calculate the product of the elevation variation ratio in geographic space and the elevation variation ratio in attribute space as the restriction index of the current elevation sequence; The steps for calculating the traffic travel restriction evaluation score are as follows: S11: Summarize the restrictiveness indexes of all high-order sequences between the settlement and its neighboring settlements, and calculate the average value of multiple restrictiveness indexes as the evaluation score of the transportation restrictiveness of the settlement.

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