KR100917768B1 - Method expanding for search cell of spatial query and system for executing the method - Google Patents

Abstract

Disclosed are a method and system for expanding a search region of a spatial query. In the spatial query search area expansion method, in the grid-based index environment in which the entire area is equally sized, the search for the query is performed by using the cell including the query location for the spatial query as the initial search area. Performing; And expanding the search area for the spatial query based on the phase relationship between the query position and the first search area when the search in the first search area is not satisfied.

Geographic Information System (GIS), Navigation System, Spatial Query, Region Query, Point Query, Query Region, Search Region, Region Expansion Technique, Search Region Expansion, Query Location, Topology, Region Expansion Direction

Description

TECHNICAL EXPANDING FOR SEARCH CELL OF SPATIAL QUERY AND SYSTEM FOR EXECUTING THE METHOD}

The present invention relates to a method and system for expanding a search region of a spatial query. More particularly, the present invention relates to an extended search region of a spatial query that expands a search region for a corresponding query when searching for a spatial query in a grid-based index environment. A method and a system for performing the method.

Recently, with the development of informatization technology, a geographic information system (GIS), which is a database of various geographic information, is widely used. The geographic information system can easily search for location information such as latitude, longitude, and address. There are advantages to it.

Such a geographic information system generally collects geographic data from public institutions or geographic information servers, converts it into an appropriate map image, and provides it to the user.

Meanwhile, a navigation system is a system that provides information for driving a vehicle such as a vehicle using an artificial satellite, and is provided with a global positioning system (GPS) receiver to predetermined information from a GPS satellite floating on the earth. Receive data and calculate its location based on the received data.

The navigation system notifies the user of the current location of the vehicle (Location), calculates an optimal route to a desired destination (Routing) and provides various services such as guiding the vehicle to travel according to the calculated route (Guidance).

The geographic information system and the navigation system have a database for storing geographic data. The geographic information system and the navigation system provide geographic and map information required by a user through querying and analyzing spatial data of a relational database.

The geographic information system and the navigation system divide national maps into grids of a certain size and store geographic data for each grid. In addition, an index is provided for each grid, and geographic data for each index can be searched using the index.

In the grid-based index environment, when a query for spatial data (hereinafter, referred to as a "spatial query") is performed, a search for geographic data for a corresponding query is performed in a default region including a query region.

Here, the spatial query may be divided into a region query and a point query, and the region query refers to a query through a specific query window, and the point query refers to a query centered on a specific query point. For example, the area query has a query form for searching for 'gas station' in 'Nonhyeon-dong', and the point query has a query form for searching for 'gas station' near 'Nonhyeon-dong Office'.

However, in the case of the above spatial query, if the query is not satisfied within the default region, the search region is extended by searching the query region.

1 is a view for explaining a conventional search region expansion technique.

As shown, when the center point 102 of the query region 101 for a spatial query is included in the cell 103 denoted by '1' in a grid index environment, the cell 103 including the center point 102 is selected. Perform the search for the corresponding query as the initial search area.

If the information about the query is not obtained from the initial search region, the search region is expanded to the cell marked with '2' to search for the enlarged region. In other words, the area extension for the existing spatial query is represented by '1', '2', '3', and '4' and is divided into '1'-> '2'-> '3'-> ' Search for the query while expanding the search area in 4 'order.

In the illustrated query region 101, the overlapped region 103 includes four cells across some cells of the cell of '1' and '2', but the query does not satisfy the initial search region. If not, the search area is expanded to the cells in all directions based on the query area 101. Therefore, the search area needs to be searched to the unnecessary extended area 104 in addition to the overlap area 103.

In other words, the existing domain expansion technique extends the search domain to the unnecessary domain, which reduces the search performance for spatial queries and increases the search domain exponentially after the initial search domain, which also reduces the search speed of the query domain. .

The present invention provides a method and system for retrieving a search region of a spatial query, which proposes a technique for avoiding unnecessary search for a spatial query and effectively expanding the search region.

The present invention provides a search region expansion method and system for a spatial query, which have prepared new region expansion criteria for expanding the search region based on the query position of the spatial query.

The present invention provides a method for performing a search on a query based on a cell including a query location for a spatial query as an initial search area in a grid-based index environment in which the entire area is equally divided into a predetermined size; And expanding a search region for the spatial query based on a phase relationship between the query position and the first search region when the search in the first search region is not satisfied. to provide.

The search region extension method of the present invention can be applied to both a region query (a query format for a specific query region) and a point query (query form centered on a specific query point), which are spatial query formats.

The expanding of the search area for the spatial query may include dividing the initial search area into quadrants, and if the query position is located in the first quadrant of the initial search area, the area expansion direction is right-up (右-上 向), when located in the second quadrant of the first search area, the area extension direction to the left-up (,-上 向), and when located in the three quadrants of the first search area, the area expansion direction to the left- Determining, in the downward direction, the area extension direction to the right-down direction when located in the fourth quadrant of the initial search area, and in the determined area expansion direction in the initial search area. It may include expanding the search area.

In addition, the present invention comprises a database for storing geographic data for each grid by dividing the entire area into a grid of a predetermined size; And performing a search for the corresponding query using the cell including the query location as the initial search area when the spatial query for the geographic data is not satisfied, and if the search in the initial search area is not satisfied, the query location and the initial search area. Provided is a search region expansion system of a spatial query including a query search unit that expands a search region for the spatial query based on a phase relationship of.

According to the present invention, it is possible to avoid unnecessary area search by determining the direction of expansion of the search area based on the query position, thereby improving search speed as well as search performance for the spatial query.

Hereinafter, a method for expanding a search region of a spatial query and a system for performing the method will be described with reference to the accompanying drawings.

The search area extension system of a spatial query according to the present invention proposes a new method for expanding a search area for a query in a spatial query in a grid-based index environment.

In particular, the search region expansion system according to the present invention provides a direction of a search region to be extended according to which position the query position exists with respect to the center of the cell in order to effectively expand the search region and avoid unnecessary region searching for the spatial query. Determine.

That is, the search region expansion system of the present invention provides a region expansion technique for changing a search region that is extended by a phase relationship between a query position and a cell including the query position.

The search region extension system of the present invention can be commonly applied to an area query and a point query, which are spatial query formats. In this specification, two query formats will be considered as the same spatial query concept.

In the present specification, 'query position' means a center point of the query region in the case of a spatial query of a query form (region query) for a specific query region, and a query form (point query) centering on a specific query point In case of a spatial query, it means the query point itself.

Referring to Fig. 2, the search region expansion method of the spatial query according to the present invention will be described in detail.

2 is a diagram illustrating the entire process of a search region expansion method of a spatial query according to the present invention.

The present invention is applicable to a grid-based index environment that stores geographic data after assigning an index for each grid by dividing the national map into a grid of a certain size.

In step S201, the search region expansion system of the spatial query receives a spatial query request for searching geographic data for each index in a grid-based index environment.

In step S202, the search region expansion system of the spatial query determines a query position corresponding to the spatial query, sets a cell including the query position as an initial search region, and performs a search for the spatial query in the initial search region. To perform.

In step S203, the search region expansion system of the spatial query determines whether the search result in the initial search region satisfies the desired information about the spatial query.

In step S204, if the search area expansion system of the spatial query does not satisfy the desired information in the first search area, a direction to expand the search area in consideration of the phase relationship between the query location and the first search area (Hereinafter referred to as 'region extension direction').

In operation S205, the search region expansion system of the spatial query expands the search region according to the region expansion direction determined in operation S204, and re-searches the spatial query in the extended search region.

3 to 8, the search area expansion process of the present invention will be described in detail.

3 is a diagram illustrating an example of a process of expanding a search area in order to explain the search area expansion method of the present invention.

As shown in Fig. 3, the center point of the query region 301, which is the default region for the spatial query, that is, the cell including the query position 302 is set as the initial search region 303 and the initial search region 303 If the search result is not satisfied, the search region for the spatial query is expanded to adjacent cells based on the initial search region 303.

According to an embodiment of the present invention, the direction of expanding an area of the search area may be determined based on the location of the query location 302 based on the center of the initial search area 303.

4 is a view for explaining the phase relationship between the query position and the initial search region in the search region expansion method of the present invention.

As shown in Fig. 4, in order to determine the query position 401, the cell corresponding to the initial search area 402 is divided into quadrants. The direction of expanding the region is determined according to which of the quadrants of the initial search region 402 is located.

5 through 8 are diagrams for describing a process of determining a region extension direction.

As shown in Fig. 5, when the query position 501 is located in the first quadrant of the initial search area 502, the direction of expanding the area is determined to be right-up and the initial search area 502 is determined. ) Expands the cell located right-up (cell labeled '2') to the secondary search region 503.

On the other hand, as shown in Fig. 6, when the query position 601 is located in the second quadrant of the initial search area 602, the direction of expanding the area is determined to be left-up and the initial search area ( Based on 602, the cell located at the left-up side (cell labeled '2') is expanded to the secondary search region 603.

On the other hand, as shown in Fig. 7, when the query position 701 is located in the third quadrant of the initial search area 702, the direction of expanding the area is determined to be left-down and the initial search area ( Based on 702, the cell located left-down (cell labeled '2') is expanded to the secondary search region 703.

On the other hand, as shown in Fig. 8, when the query position 801 is located in the fourth quadrant of the initial search area 802, the direction of expanding the area is determined to be right-down and the initial search area ( The cell located right-down (cell labeled '2') with reference to 802 is expanded to the secondary search area 803.

On the other hand, although the figure is omitted, if the query position coincides with the center point of the initial search region, the direction of expanding the region is determined as omnidirectional, and the second search is performed on cells adjacent to all directions based on the initial search region. Expand to the area.

Since the initial search areas 502, 602, 702, and 802 have already searched for the spatial query, only the extended secondary search areas 503, 603, 703, and 803 are searched. Redo the search for the query.

In addition, when the search result in the secondary search region is not satisfied, the search region may be further extended in all directions based on the secondary search region.

The search area extension method of the present invention divides the initial search area into quadrants to determine in which phase the initial search area (the cell including the query location) is located. The area extension direction is determined according to which quadrant position of the initial search area is located, and the search area is expanded in the area extension direction determined accordingly.

Hereinafter, a search region expansion system of a spatial query for performing the search region expansion method of the present invention will be described. 9 is a diagram illustrating an internal configuration of a search region expansion system of a spatial query according to the present invention.

As shown in FIG. 9, the search area expansion system of the present invention may include a database 910 and a query search unit 930.

The database 910 is a means for storing geographic data on a national map. The database 910 is preferably divided into a grid of a certain size to store geographic data for each grid and to give an index for each grid. According to such a configuration, it is possible to search geographic data for each index by using a grid-based index.

The query search unit 930 performs a search for a corresponding query using a cell including a query position as an initial search area in a spatial query for the geographic data in a grid-based index environment. If the search result is not satisfied, the search region for the spatial query is expanded based on the phase relationship between the query position and the initial search region.

The query search unit 930 may include a search area setting unit 931 and a search execution unit 933.

The search region setting unit 931 sets the initial search region according to the query position, or expands the search region for the spatial query based on the initial search region when the search region needs to be expanded.

The search execution unit 933 performs a search for the spatial query in the determined search area when the initial search area or the extended search area is determined through the search area setting unit 931.

In particular, the search area setting unit 931 does not satisfy the search result in the first search area, and thus, when the search area is expanded, the search area setting unit 931 expands the area according to which phase in the initial search area is located. After determining the direction, the search area is extended from the initial search area to the determined area expansion direction.

Preferably, the search region setting unit 931 divides the first search region into quadrants, and then, when the query position is located in the first quadrant of the first search region, the region extension direction is right-upward, and the first search region is divided into four quadrants. If it is located in the second quadrant of the search area, it is determined to be left-up, if it is located in the third quadrant of the first search area, to the left-down, and if it is located in the fourth quadrant of the first search area, it is determined to be right-down.

On the other hand, the search area setting unit 931 determines the area expansion direction in all directions when the query position is located at the center point of the first search area.

Subsequently, the search region setting unit 931 expands adjacent cells in the determined region expansion direction based on the initial search region to the search region for the spatial query.

In addition, if a search result in the extended search area after the initial search area does not satisfy desired information, the search area setting unit 931 may further expand the search area in all directions based on the extended search area. have.

Accordingly, the present invention can improve the search performance by avoiding the expansion and the search for unnecessary areas by expanding the search area in consideration of the phase relationship between the query location and the cell including the query location when expanding the search area for the spatial query. .

The search area expansion method of the spatial query according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program instructions recorded on the media may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the claims below but also by the equivalents of the claims.

1 is a view for explaining a conventional search region expansion technique in a search process for a spatial query.

2 is a diagram illustrating the entire process of a search region expansion method of a spatial query according to the present invention.

3 is an example of expanding a search region for a spatial query, and is a view for explaining a search region expansion technique of the present invention.

4 is a view for explaining the phase relationship between the query position and the initial search region in the search region expansion method of the present invention.

5 through 8 are diagrams for describing a process of determining an extension direction of a search area for a spatial query.

9 is a diagram illustrating a system internal configuration for executing a method for expanding a search region of a spatial query of the present invention.

<Explanation of symbols for the main parts of the drawings>

910: database 930: query search unit

931: search area setting unit 933: search execution unit

Claims (14)

In a grid-based index environment where an entire area is divided into equal parts, Performing a search for a corresponding query using a cell including a query location for a spatial query as an initial search region; And, Expanding the search region for the spatial query based on a phase relationship between the query position and the first search region when the search in the first search region is not satisfied; The location of the query, When the spatial query is a query format for a specific query region, the center point of the query region, and when the spatial query is a query format centered on a specific query point, the query region is extended. Way. delete The method of claim 1, Expanding a search region for the spatial query based on the phase relationship between the query position and the initial search region, Determining an area extension direction according to which phase of the initial search area is located; Expanding a search area in the determined search area extension direction from the first search area; Search region expansion method of a spatial query comprising a. The method of claim 3, Determining an area extension direction according to which phase in the initial search area the query position is located, Dividing the initial search area into quadrants; If the query position is located in the first quadrant of the first search region, determining the region expansion direction as a right-up direction; If the query position is located in two quadrants of the initial search region, determining the region expansion direction to be left-up; If the query position is located in three quadrants of the first search region, determining the region expansion direction from left to bottom; If the query position is located in four quadrants of the initial search region, determining the region expansion direction as a right-down direction Search region expansion method of a spatial query comprising a. The method of claim 3, Expanding a search region for the spatial query based on the phase relationship between the query position and the initial search region, If the search in the extended search region is not satisfied, further expanding the search region in all directions in the extended search region; The search region expansion method of the spatial query further comprising. The method of claim 4, wherein Determining an area extension direction according to which phase in the initial search area the query position is located, If the query position is located at the center point of the initial search region, determining the region expansion direction in an omnidirectional direction The search region expansion method of the spatial query further comprising. A computer-readable recording medium in which a program for executing the method of any one of claims 1 and 3 is recorded. A database for storing geographic data for each grid by dividing the entire area into a grid having a predetermined size; And, When the spatial query for the geographic data is performed, a search for a corresponding query is performed using a cell including a query location as an initial search area, and the search location and the phase of the first search area are not satisfied. A query search unit that expands a search area for the spatial query based on a relationship; The query search unit, When the spatial query is a query format for a specific query region, the center point of the query region is applied as the query position, or when the spatial query is a query format for a specific query point, the query point is applied as the query position. Search system expansion system for a spatial query, characterized in that. delete The method of claim 8, The query search unit, A search region setting unit configured to set the initial search region or expand the search region for the spatial query according to the query position; A search execution unit for searching a corresponding query from the geographic data of the initial search area or the extended search area; Search area expansion system of a spatial query comprising a. The method of claim 10, The search area setting unit, Determine an area extension direction according to which phase in the initial search area the query location is located; Extending a search area from the initial search area toward the determined area extension direction; Spatial query search region expansion system characterized in that the. The method of claim 11, The search area setting unit, Divide the initial search area into quadrants When the query position is located in the first quadrant of the first search region, the region expansion direction is determined to be right-upward, If the query position is located in two quadrants of the initial search region, the region expansion direction is determined to be left-up, If the query position is located in the three quadrants of the initial search region, the direction of expanding the region is determined to be left-down. If the query position is located in four quadrants of the initial search region, determining the direction of expanding the region in a right-down direction Spatial query search region expansion system characterized in that the. The method of claim 12, The search area setting unit, If the query position is located at the center point of the first search region, determining the region expansion direction in a forward direction Spatial query search region expansion system characterized in that the. The method of claim 11, The search area setting unit, If the search in the extended search region is not satisfied, further expanding the search region in all directions from the extended search region under the control of the search execution unit; Spatial query search region expansion system characterized in that the.

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