KR100963352B1 - Indexing method of trajectory data and apparatus using the method - Google Patents

Abstract

A method of indexing trajectory data and an apparatus using the method are provided. The indexing apparatus of the present invention includes a time interval setting unit for setting a plurality of time intervals, line segments including spatiotemporal data for displaying movement information of an object using spatial coordinates and a time scale, wherein each of the line segments is included. A time section, wherein the time section is one of the plurality of set time sections, and each of the set time sections from a line segment included in each of the set plurality of time sections It includes an index generator for generating an index structure corresponding to the through, it can effectively process the region query for a large trajectory data.

Trajectory data, region query, indexing method, index

Description

Indexing method of trajectory data and a device using the method {INDEXING METHOD OF TRAJECTORY DATA AND APPARATUS USING THE METHOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of indexing trajectory data, and more particularly, to an indexing method for improving range query performance for a large amount of trajectory data and an indexing apparatus using the method.

Recently, due to the proliferation of portable mobile terminals such as mobile phones and portable digital assistants (PDAs) and the development of communication technologies, various services are provided that utilize spatial location information according to the flow of moving objects. have. The spatial position information according to the time flow of the object may be represented as spatio-temporal data. Spatiotemporal data refers to data including spatial coordinates and time parameters. For example, if the spatial coordinates are (x, y) and the time scale is t, the space-time data may be represented as (x, y, t). Spatio-temporal data (x, y, t) in which two-dimensional space coordinates (x, y) and a time scale t are combined may represent a point in three-dimensional space-time.

The movement path of the objects may be represented by a set of line segments given in space-time, and the set of line segments represented is called a trajectory. The system may track the location of the objects based on the trajectory information of the moving objects, and may combine the road information and the vehicle information to determine the behavior pattern of the user of the moving object. The system may use the identified user's behavior pattern for business marketing.

User queries for moving objects may include future prediction queries and historical historical queries. The future prediction query is a query for predicting and searching a future position of a moving object, and the past history query is a query for searching for a position in which the moving object has moved in the past. The future prediction query may predict the future position of the moving object using the moving speed and the moving direction from the current position of the moving object.

Historical historical queries may include range queries, trajectory queries, complex queries, and the like. A region query is a query for searching for a moving object existing in a given query region, and a trajectory query is a query for searching for a path that a moving object moves during a given time interval. The compound query is a combination of the region query and the trajectory query, which retrieves the trajectory of the moving object located in the specific region for a given time interval.

The indexing method and apparatus of the present invention aim to effectively process a region query in a large trajectory database.

An indexing method and apparatus of the present invention aims to effectively respond to an area query for a recent time interval.

The indexing method and apparatus of the present invention aim to provide a constant search performance even with a change in the distribution of a moving object.

In order to achieve the above object, the indexing apparatus according to an embodiment of the present invention may include a time section setter, a time section identifier and an index generator. The time section setting unit sets a plurality of time sections. The time section identification unit classifies the line segments according to a time section in which each of the line segments is included. The line segment includes spatio-temporal data indicating movement information of an object using spatial coordinates and a time scale. The index generator generates an index structure corresponding to each of the set plurality of time intervals from line segments included in each of the set plurality of time intervals.

An indexing apparatus according to another embodiment of the present invention may include a line segment generator, an insert operator, and a controller. The line segment generator generates a line segment including spatiotemporal data displaying object movement information using a spatial coordinate and a time scale. The insertion operator inserts the generated line segment into the first index structure and updates the time scale of the first index structure using the time scale of the inserted line segment. The controller determines whether to generate a second index structure by comparing the number of line segments included in the first index structure with a threshold.

An indexing method according to another embodiment of the present invention comprises the steps of: setting a plurality of time intervals, generating line segments including space-time data displaying the movement information of an object using a spatial coordinate and a time scale; And classifying the line segments according to each of the generated line segments, wherein the time intervals are included in each of the set plurality of time intervals. The method may include generating an index structure corresponding to each of the set plurality of time intervals from line segments.

An indexing method according to another embodiment of the present invention includes generating a line segment including spatiotemporal data indicating movement information of an object using a spatial coordinate and a time scale, and converting the generated line segment into a first index structure. Inserting, updating a time scale of the first index structure by using the time scale of the inserted line segment, and comparing the number of line segments included in the first index structure with a threshold to obtain a second index structure. Determining whether to generate.

According to the indexing method and apparatus of the present invention, an area query can be efficiently processed in a large trajectory database.

The indexing method and apparatus of the present invention can effectively respond to an area query for a recent time interval by setting a plurality of time intervals.

The indexing method and apparatus of the present invention can provide a constant search performance even by a change in the distribution of the moving object by dividing the set space and allowing the number of moving objects to be equally distributed in the divided space.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited or limited by the embodiments. Like reference numerals in the drawings denote like elements.

Spatio-temporal data described herein is described by taking an example of describing a two-dimensional space, i.e., a movement on a plane and a time course. However, those skilled in the art will readily be able to deduce from the description herein the indexing method and system when extended to a higher level or applied to a lower level.

Spatio-temporal data representing two-dimensional space and time dimensions are represented by three-dimensional data of (x, y, t). In general, spatiotemporal data representing an L-dimensional space and a temporal dimension is represented by (L + 1) -dimensional spatiotemporal data.

1 is a diagram illustrating an index structure used in an indexing method according to an embodiment of the present invention.

Referring to FIG. 1, the time index table 100 stores configuration information of an index for each time period. The time index table 100 stores the configuration information of the index I ₀ 110 for the time interval t ₀ 101 and the configuration information of the index I ₁ 120 for the time interval t ₁ 102. . The information stored in the time index table may include location information on the main memory or the storage device when each index is stored in the main memory or the storage device.

The index I ₀ 110 corresponding to the time interval t ₀ 101 includes a trajectory representing the movement of the object in the two-dimensional space. In this case, the indexing method may divide the two-dimensional space represented by x and y into m sub-space regions (or cell regions). The two-dimensional space indicated by the index I ₀ 110 is divided into four subspace regions, each of which has a corresponding index structure 111, 112, 113, 114.

Index I ₀ 110 or index I ₁ 120 may be implemented as a two-dimensional tree structure or a hash table. Index I ₀ (110) or index I ₁ (120) is an entry of a storage location of a three-dimensional R * tree index constructed of line segments existing in a subspace region corresponding to space-time data (x, y, t). Can have The 3D R * tree may have a trajectory identifier and a segment identifier for the line segments in the subspace region as entries.

Index I ₀ 110 or index I ₁ 120 may include k line segments. The line segments constituting the trajectory of the moving object may be inserted into the index structure in the collected time order. After k line segments are inserted at index I ₀ 110, the indexing method may create the next index I ₁ 120 and insert the additionally collected line segments at index I ₁ 120. Similarly, after k line segments are inserted in the index structure I _{n -1} 130 corresponding to the time interval t _{n -1} (103), the indexing method performs the index structure corresponding to the next index time interval t _n (104). I _n 140 may be generated. In this manner, the indexing method may generate an index structure corresponding to each of the time intervals.

The indexing method may classify the line segments according to time and classify the line segments included in each of the time intervals according to space. The indexing method classifies the line segments according to time in the uppermost layer, so that the line segments for the currently moving object may be inserted into the index structure corresponding to the last time interval.

In general, the line segment to be searched for the region query is likely to be the currently collected line segment or the recently processed line segment. The indexing method according to embodiments of the present invention can reduce the search cost for the region query by facilitating access to the index structure corresponding to the last time interval. In addition, the indexing method according to the embodiments of the present invention classifies the collected line segments according to time and then classifies them according to space (sub-space area) to filter the overlapping information among the line segments searched for the area query. Can be minimized or eliminated.

The indexing method stores the index structure I _n 140 corresponding to the last time interval t _n 104 accessible by the insert operation in main memory (not shown) and excludes the index structure I _n 140. Index structures can be stored in a storage device (not shown). In general, since the access time to the main memory is smaller than the access time to the storage device, the indexing method may quickly search the index structure I _n 140 corresponding to the last time interval t _n 104. Since the line segment to be searched for the region query is likely to be included in the last time interval t _n 104, the indexing method may shorten the search time of the region query.

The indexing method may determine the number k of line segments that the index structure I _n 140 can store based on the size of the main memory. The indexing method may divide the two-dimensional space represented by the index structure I _n 140 into m subspace regions. The index structure I _n 140 may have, as an entry, a storage location of a three-dimensional R * tree index constructed from line segments existing in a subspace region corresponding to space-time data (x, y, t), and each sub It is a multilevel multiple indices with sub-indexes for each space. The indexing method supports non-uniform spatial region partitioning (cell region partitioning) in which each divided subspace region can store (k / m) line segments. In this case, the indexing method may manage partitioning information for the entire spatial region using a two-dimensional tree structure.

The indexing method divides the space area into subspace areas so that the number of line segments included in each subspace area is uniform, so that even if a moving object is concentrated in a specific space area, the search load can be evenly distributed for each subspace area.

The indexing method may generate a 3D R tree having a relatively small size for each divided subspace region. The indexing method may improve search performance for each subspace region by using the generated 3D R tree.

An insert operation of the indexing method may be performed as follows. The insert operation may insert the collected line segments into the index structure I _n 140 corresponding to the last time interval t _n 104. The indexing method may perform an insert operation and a search operation on the index structure I _n 140.

The indexing method may not perform an insert operation on the remaining index structures except for the index structure I _n 140 corresponding to the last time interval t _n 104. The indexing method may perform a search operation on the remaining index structures.

The insert operation may receive a maximum number k of line segments that can be stored in the line segment and the index structure. The insert operation may output a current index current-index and a previous index prev-index constructed using a three-dimensional R * tree structure, and output a two-dimensional tree structure and a time index table 100 managing spatial partition information. have. The initialization process of the insert operation can create a new index structure as current-index.

If the number of line segments in the current-index is less than k, the indexing method may insert the line segments into the current-index. The insert operation may use the time information of the line segment of the moving object to maintain the minimum time and the maximum time information of the current time interval. The insertion operation may update the maximum time information of the current time interval by using the time information of the line segment of the moving object. The insert operation may store the line segments of the moving object in the storage area allocated to the current-index and increase the number of line segments in the current-index by one.

If the number of line segments in the current-index is greater than or equal to k and n is greater than 2, the indexing method may store the current-index on main memory as a prev-index on the storage device and create a new index structure as the current-index. .

The indexing method may divide a spatial region corresponding to a new current-index into m cell regions, and store information about each of the divided cell regions in a two-dimensional tree. The indexing method may store the minimum time and the maximum time of the line segments inserted into the two-dimensional tree in an entry of the time index table 100. In this case, the indexing method may store address information in the storage device or the main memory in which the 2D tree is stored.

The indexing method may generate a 3D R * tree for each cell region of the new current-index and store line segments in the generated 3D R * tree.

2 is an operation flowchart illustrating an example of an indexing method using the time index table 100 of FIG. 1.

Referring to FIG. 2, the indexing method generates a line segment including spatio-temporal data that displays movement information of an object using spatial coordinates and a time parameter (S210).

The indexing method inserts the generated line segment into the index structure (S220).

The indexing method updates the time scale of the index structure by using the time scale of the inserted line segment (S230).

The indexing method compares the number of line segments included in the index structure with a threshold k (S240). The indexing method may determine whether the number of line segments included in the index structure is less than k. The indexing method may determine whether to generate a new index structure using the comparison result of step S240.

If the number of line segments included in the index structure is less than k, the indexing method performs step S210 again.

The indexing method stores the index structure in the storage device when the number of line segments included in the index structure is greater than or equal to k (S250).

The indexing method generates a new index structure instead of the index structure stored in the storage device (S260). The indexing method can store the new index structure in main memory.

The indexing method may insert the line segment generated in operation S220 into the new index structure when the new index structure is created.

The indexing method may set the threshold k based on the size of the main memory. The indexing method may divide the entire space represented by the spatial coordinates into a plurality of spatial cells. The indexing method may generate the new index structure such that the new index structure includes a sub index corresponding to each of the divided spatial cells.

3 is an operational flowchart illustrating an indexing method according to another embodiment of the present invention.

Referring to FIG. 3, the indexing method sets a plurality of time intervals (S310).

The indexing method generates line segments including spatiotemporal data for displaying movement information of an object using spatial coordinates and a time scale (S320).

The indexing method divides the generated line segments according to a time interval in which each of the generated line segments is included (S330). At this time, the time interval is any one of the plurality of time intervals set in step S310.

The indexing method generates an index structure corresponding to each of the set plurality of time intervals from line segments included in each of the set plurality of time intervals (S340).

For example, in step S310, the indexing method may set a first time interval, a second time interval, and a third time interval.

The indexing method may determine whether each of the line segments is included in the first time interval, the second time interval, or the third time interval based on the time scale of each of the generated line segments (S330). . The indexing method may generate an index structure corresponding to the first time interval by collecting line segments included in the first time interval (S340). Similarly, the indexing method may generate an index structure corresponding to the first time interval by collecting line segments included in the second time interval (S340).

The indexing method may set a time interval closest to a current time among the set time intervals as a first time interval, and store an index structure corresponding to the first time interval in a main memory. Since the main memory has a shorter access time than the storage device, the indexing method may shorten the area query search time for the index structure corresponding to the first time interval closest to the current time.

The indexing method may store an index structure corresponding to the second time interval except the first time interval and an index structure corresponding to the third time interval in a storage device. The indexing method may insert the additionally generated line segment in the first time interval. The indexing method may not insert the additionally generated line segment into the remaining index structure except for the index structure corresponding to the first time interval.

8 is a flowchart illustrating an example of step S340 of FIG. 3 in more detail.

Referring to FIG. 8, the indexing method divides the entire space represented by the spatial coordinates into a plurality of spatial cells (S810).

The indexing method generates a sub index corresponding to each of the divided spatial cells (S820).

The indexing method generates an index structure including the generated sub index (S830). In this case, the generated sub-index structure may be a three-dimensional R * tree structure for storing three-dimensional space-time data (x, y, t). The generated index structure may be a two-dimensional tree structure including partition information of the spatial cells.

In the indexing method, in operation S810, the entire space may be divided into the plurality of space cells such that each of the plurality of space cells includes the same or nearly the same number of line segments. In this case, the indexing method may prevent concentration of computational load on a specific spatial cell during a region query search by allowing each of the plurality of spatial cells to include the same or nearly the same number of line segments.

7 is a flowchart illustrating a search method for an index structure generated by the indexing method of FIG. 2 or 3.

Referring to FIG. 7, the search method selects an index structure corresponding to time intervals included in a time interval of an input query (S710).

The search method searches for line segments having spatial coordinates overlapping the spatial region of the query from the selected index structure (S720).

The search method may perform a region query search on the index structure generated by the indexing method of FIG. 2 or 3. The index structure to be searched for the search method is current-index corresponding to the last time interval t _n , prev-index corresponding to time interval t _{n -1} , and time intervals from time interval t ₀ to time interval t _{n -2} . May be a disk-index corresponding to. The index structures current-index, prev-index, and disk-index may be implemented using a three-dimensional R * tree structure, and information about time intervals of the index structures current-index, prev-index, and disk-index may be used. Can be stored in a time index table.

The index structure may include spatial coordinates representing a two-dimensional space region. Each index structure may include a sub-index corresponding to a cell area obtained by dividing the two-dimensional space region, and each sub-index may be a two-dimensional tree storing spatial partition information.

The search method may receive the index structure, the time index table, the sub index, and the query Q. The search method may output a result set A that satisfies the query Q in response to the input.

The search method may select a two-dimensional tree included in a time interval of a given query Q from the time index table. The search method may search for the prev-index stored in the main memory if the time section of the query Q corresponds to the time section of the prev-index, and the current-index if the time section of the query Q corresponds to the time section of the current-index. You can search.

The search method may search a cell region overlapping the spatial region of the query Q in the selected two-dimensional tree when the time interval of the query Q is smaller than the minimum time of the time interval of the prev-index. The search method may search a disk-index corresponding to the searched cell area. When there are a plurality of cell regions overlapping the spatial regions of the query Q, the searching method may perform the searching process on each of the found cell regions.

4 is a block diagram illustrating an example of an indexing apparatus 400 that performs the indexing method of FIG. 3.

Referring to FIG. 4, the indexing apparatus 400 includes a time section setting unit 410, a time section identification unit 420, and an index generator 430.

The time section setting unit 410 sets a plurality of time sections.

The time section identification unit 420 classifies the line segments according to the time sections in which each of the line segments is included. Each of the line segments may include spatiotemporal data indicating movement information of the object using spatial coordinates and a time scale. The time interval may be any one of the set time intervals.

The index generator 430 generates an index structure corresponding to each of the plurality of set time periods from line segments included in each of the plurality of set time periods. The index generator 430 may classify the line segments classified according to the set plurality of time intervals for each of the set plurality of time intervals. The index generator 430 may collect line segments classified for each of the set plurality of time intervals, and generate an index structure from the collected line segments.

FIG. 5 is a block diagram illustrating another example of the indexing apparatus 500 that performs the indexing method of FIG. 3.

Referring to FIG. 5, the indexing apparatus 500 includes a time section setting unit 510, a time section identification unit 520, an index generator 530, a first control unit 540, and a second control unit 550. do.

The time section setting unit 510 sets a plurality of time sections.

The time section identifying unit 520 divides the line segments according to the time section.

The index generator 530 collects line segments divided according to time intervals and generates an index structure corresponding to each of the time intervals.

The first controller 540 may store and manage an index structure corresponding to the first time interval closest to the current time among the set time intervals in the main memory.

The second controller 550 may store and manage an index structure corresponding to the remaining time intervals other than the first time interval among the set time intervals in the storage device.

The index generator 530 may insert the line segment generated by the moving object currently moving in the index structure corresponding to the first time interval. When the index structure corresponding to the first time interval is stored in the main memory, the indexing device 500 may quickly access the main memory, thereby shortening the execution time of the insertion operation of the newly created line segment.

The index generator 530 may not insert a newly generated line segment in the index structure corresponding to the remaining time intervals other than the first time interval. Since the remaining time intervals are stored in a storage device that is slower than main memory, the indexing apparatus 500 may avoid the case where the execution time of the insert operation of the line segment becomes long.

In general, the search target of the region query is more likely to occur more frequently in the current time interval than in the past time interval, so the indexing apparatus 500 shortens the access time for the index structure corresponding to the time interval closest to the current time interval. This can shorten the search time of the query.

FIG. 6 is a block diagram illustrating another example of the indexing apparatus 600 that performs the indexing method of FIG. 3.

Referring to FIG. 6, the indexing apparatus 600 includes a time section setting unit 610, a time section identification unit 620, an index generator 630, a time dimension search unit 640, and a spatial dimension search unit 650. It includes.

The time section setting unit 610 sets a plurality of time sections.

The time section identification unit 620 classifies the line segments according to the time section.

The index generator 630 collects line segments divided according to time intervals and generates an index structure corresponding to each of the time intervals.

The time dimension retrieval unit 640 may select an index structure corresponding to the time intervals included in the time interval of the received query.

The spatial dimension search unit 650 may search line segments having spatial coordinates overlapping the spatial region of the query from the selected index structure.

The index generator 630 may divide the entire space represented by the spatial coordinates into a plurality of spatial cells, and generate a sub index corresponding to each of the divided plurality of spatial cells. The index generator 630 may divide the entire space into a plurality of space cells so that each of the plurality of divided space cells includes the same (same or very similar) number of line segments. The indexing apparatus 600 may increase the efficiency of the search process for the spatial coordinates by adjusting the number of line segments included in each sub index evenly.

The index generator 630 may manage the information on the divided spatial cells using a database having a two-dimensional tree structure. The index generator 630 may manage spatiotemporal data for each of the divided spatial cells using a 3D tree structure database. The index structure may be a multilevel index structure including an index structure for a time interval and a sub index for a spatial region.

FIG. 9 is a diagram illustrating an example of an indexing apparatus 900 that performs the indexing method of FIG. 2.

Referring to FIG. 9, the indexing apparatus 900 includes a line segment generator 910, an insert operator 920, and a controller 930.

The line segment generator 910 generates a line segment including spatiotemporal data displaying the movement information of the object using a spatial coordinate and a time scale.

The insertion operator 920 inserts the generated line segment into the first index structure and updates the time scale of the first index structure by using the time scale of the inserted line segment.

The controller 930 determines whether to generate a second index structure by comparing the number of line segments included in the first index structure with a threshold. If the number of line segments included in the first index structure is smaller than a threshold, the controller 930 may transmit the first index structure to the insertion operator 920 without generating a second index structure. In this case, the insertion operator 920 may insert the newly created line segment into the first index structure received from the controller 930.

If the number of line segments included in the first index structure is greater than or equal to a threshold value, the controller 930 may generate a second index structure. In this case, the controller 930 may transmit the generated second index structure to the insertion operator 920. The insertion operator 920 may insert the newly created line segment into the second index structure received from the controller 930. The controller 930 may store and manage the first index structure stored in the main memory in the storage device, and store and manage the generated second index structure in the main memory. The controller 930 may set a threshold based on the size of the main memory.

The controller 930 divides the entire space represented by the spatial coordinates into a plurality of spatial cells, and generates the second index structure such that the second index structure includes a sub-index corresponding to each of the divided spatial cells. Can be.

The indexing method according to the embodiments of 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 diagram illustrating an index structure used in an indexing method according to an embodiment of the present invention.

2 is an operation flowchart illustrating an example of an indexing method using the time index table 100 of FIG. 1.

3 is an operational flowchart illustrating an indexing method according to another embodiment of the present invention.

4 is a block diagram illustrating an example of an indexing apparatus 400 that performs the indexing method of FIG. 3.

FIG. 5 is a block diagram illustrating another example of the indexing apparatus 500 that performs the indexing method of FIG. 3.

FIG. 6 is a block diagram illustrating another example of the indexing apparatus 600 that performs the indexing method of FIG. 3.

7 is a flowchart illustrating a search method for an index structure generated by the indexing method of FIG. 2 or 3.

8 is a flowchart illustrating an example of step S340 of FIG. 3 in more detail.

FIG. 9 is a diagram illustrating an example of an indexing apparatus 900 that performs the indexing method of FIG. 2.

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

410: time section setting unit

420: time interval identification unit

430: index generator

Claims (23)

A time section setting unit for setting a plurality of time sections; Line segments including spatiotemporal data displaying movement information of an object using spatial coordinates and a time scale, wherein each of the line segments includes a time period, wherein the time period is any one of the set time periods. A time interval identification unit classified according to; And Index generation unit for generating an index structure corresponding to each of the plurality of set time periods from the line segments included in each of the plurality of set time periods Indexing device comprising a. The method of claim 1, A first controller configured to store and manage an index structure corresponding to a first time interval closest to a current time among the set time periods in a main memory; And A second controller configured to store and manage an index structure corresponding to time intervals other than the first time interval in a storage device; Indexing device further comprising. The method of claim 1, The index generator And dividing the entire space represented by the spatial coordinates into the plurality of spatial cells such that each of the plurality of spatial cells includes the same number of line segments. The method of claim 1, The index generator And dividing the entire space represented by the spatial coordinates into a plurality of spatial cells, and managing information of the divided plurality of spatial cells using a two-dimensional tree data structure. The method of claim 1, The index generator And dividing the entire space represented by the spatial coordinates into a plurality of spatial cells, and managing spatiotemporal data for each of the plurality of divided spatial cells using a three-dimensional tree data structure. The method of claim 1, The index generator And a line segment for a moving object that is currently moving, is inserted into an index structure corresponding to a first time interval closest to a current time among the set time intervals. The method of claim 6, The index generator And inserting a line segment for the currently moving moving object only for a corresponding index structure other than the first time interval. The method of claim 1, A time dimension retrieval unit for selecting an index structure corresponding to time intervals included in the time interval of the received query; And Spatial dimension retrieval unit for retrieving line segments having spatial coordinates overlapping the spatial region of the query from the selected index structure Indexing device further comprising. The method of claim 1, The index generator And dividing the entire space represented by the spatial coordinates into a plurality of spatial cells, and generating a sub-index corresponding to each of the divided plurality of spatial cells. A line segment generator configured to generate a line segment including space-time data for displaying movement information of the object using a spatial coordinate and a time scale; An insertion operation unit inserting the generated line segment into a first index structure that stores the line segment, and updating a time scale of the first index structure by using the time scale of the inserted line segment; And A controller configured to generate a second index structure separate from the first index structure when the number of line segments included in the first index structure is greater than or equal to a predetermined number. Indexing device comprising a. The method of claim 10, And the insertion operator inserts a newly created line segment into the generated second index structure. The method of claim 11, The control unit And when the second index structure is generated, storing and managing the first index structure in a storage device, and storing and managing the generated second index structure in main memory. The method of claim 11, The control unit And dividing the entire space represented by the spatial coordinates into a plurality of spatial cells, and generating the second index structure including a sub-index corresponding to each of the divided spatial cells. Setting a plurality of time intervals; Generating line segments including spatiotemporal data representing movement information of the object using spatial coordinates and a time scale; Dividing the generated line segments according to a time interval in which each of the generated line segments is included, wherein the time interval is any one of the set plurality of time intervals; And Generating an index structure corresponding to each of the set plurality of time intervals from line segments included in each of the set plurality of time intervals. Indexing method comprising a. The method of claim 14, Storing an index structure corresponding to a first time interval closest to a current time among the set plurality of time intervals in a main memory; And Storing an index structure corresponding to time intervals other than the first time interval in a storage device; Indexing method further comprising. The method of claim 14, Generating the index structure Dividing the entire space represented by the spatial coordinates into a plurality of spatial cells; Generating a sub-index corresponding to each of the divided spatial cells; And Generating the index structure including the generated sub-index Indexing method comprising a. The method of claim 16, Dividing the entire space into the plurality of space cells And dividing the entire space into the plurality of space cells such that each of the plurality of space cells includes the same number of line segments. The method of claim 14, Selecting an index structure corresponding to time intervals included in the time interval of the received query; And Retrieving line segments having spatial coordinates overlapping spatial regions of the query from the selected index structure Indexing method further comprising. Generating a line segment including spatiotemporal data displaying movement information of the object using a spatial coordinate and a time scale; Inserting the generated line segment into a first index structure that stores the line segment; Updating the time scale of the first index structure using the time scale of the inserted line segment; And Generating a second index structure separate from the first index structure if the number of line segments included in the first index structure is greater than or equal to a predetermined number; Indexing method comprising a. The method of claim 19, Inserting the newly created line segment into the generated second index structure Indexing method further comprising. The method of claim 20, When the second index structure is generated, storing the first index structure in a storage device and storing the generated second index structure in main memory. Indexing method further comprising. The method of claim 20, Generating the second index structure, Dividing the entire space represented by the spatial coordinates into a plurality of spatial cells; Generating a sub-index corresponding to each of the divided spatial cells; And Generating the second index structure including the generated sub-index Indexing method comprising a. A computer-readable recording medium in which a program for executing the method of any one of claims 14 to 22 is recorded.

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