Spatio-temporal data management system, spatio-temporal data management method, and machine-readable storage medium thereof

• US 9,098,591 B2
• Filed: 03/01/2013
• Issued: 08/04/2015
• Est. Priority Date: 06/18/2012
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hayashi, Hideki, Asahara, Akinori, Obara, Kiyohiro, Sato, Akiko
• Primary Examiner(s): THAI, HANH B
• Application Number:
  US13/782,675
• Publication Number:
  US 20130339371A1
• Time in Patent Office: 886 Days
• Field of Search: 707/743, 707/758, 707787-788
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2458 Special types of queries, e.g. statistical queries, fuzzy queries or distributed queries
• CPC Class Codes: G06F 16/9537 Spatial or temporal dependent retrieval, e.g. spatiotemporal queries

Abstract

It is provided a spatio-temporal data management system for managing time series data associated with a spatio-temporal region, comprising: a processor for executing a program; a memory for storing the program; and a storage device for storing the time series data. The processor segments the spatio-temporal region in time and space to generate a plurality of spatio-temporal segments, assigns, in consideration of temporal and spatial proximity of the plurality of spatio-temporal segments, identifiers for uniquely identifying the plurality of spatio-temporal segments, each of the identifiers being expressed with a one-dimensional integer value; and determines an arrangement of the time series data so that pieces of data of spatio-temporal segments that are close in the assigned identifiers are arranged close on the storage device.

Claims

1. A spatio-temporal data management system for managing time series data associated with a spatio-temporal region, comprising:

a processor configured to execute a program;

a memory for storing the program; and

a storage device for storing the time series data, wherein the processor is configured to;

segment the spatio-temporal region in time and space to generate a plurality of spatio-temporal segments;

assign, in consideration of temporal and spatial proximity of the plurality of spatio-temporal segments, identifiers for uniquely identifying the plurality of spatio-temporal segments, each of the identifiers being expressed with a one-dimensional integer value, wherein;

the identifiers of a first set of values that are smaller than a second set of values are assigned to spatio-temporal segments of a first period of time that is older than a second period of time to which the identifiers of the second set of values are assigned, and

for spatio-temporal segments of an identical period of time, the identifiers of close values are assigned to spatio-temporal segments that are close in spatial distance; and

determine an arrangement of the time series data such that pieces of data of spatio-temporal segments that are close in the assigned identifiers are arranged close on the storage device.

2. The spatio-temporal data management system according to claim 1, wherein the processor is configured to associate time series data on a boundary of each of the plurality of spatio-temporal segments with the each of the plurality of spatio-temporal segments.

3. The spatio-temporal data management system according to claim 2, wherein the processor is configured to generate the time series data on the boundary of the each of the plurality of spatio-temporal segments by linear interpolation.

4. The spatio-temporal data management system according to claim 1,

wherein the time series data includes grid time series data including at least one piece of data in the plurality of spatio-temporal segments, and point time series data including at least one spatial coordinate in the plurality of spatio-temporal segments,

wherein the processor is configured to:

assign one of a common identifier and correlated identifiers to the grid time series data and the point time series data, and specify the one of the common identifier and the correlated identifiers to search the grid time series data and the point time series data in association with each other.

5. The spatio-temporal data management system according to claim 1,

wherein the processor is configured to search the time series data in a first determination step and a second determination step,

wherein, in the first determination step, the processor is configured to calculate identifiers of spatio-temporal segments satisfying search conditions of time and space, and extract the spatio-temporal segments corresponding to the calculated identifiers as result candidates, and

wherein, in the second determination step, the processor is configured to match the time series data associated with the spatio-temporal segments extracted as the result candidates and the search conditions, to thereby generate search results.

6. The spatio-temporal data management system according to claim 5,

wherein data of the plurality of spatio-temporal segments includes a maximum value and a minimum value of the time series data within the plurality of spatio-temporal segments, and

wherein, in the first determination step, the processor is configured to:

compare search conditions of the time series data with at least one of the maximum value and the minimum value of the time series data; and

extract spatio-temporal segments which correspond to the calculated identifiers and satisfy the search conditions of the time series data as the result candidates.

7. A spatio-temporal data management method to be executed by a computer system for managing time series data associated with a spatio-temporal region, the computer system including a processor for executing a program, a memory for storing the program, and a storage device for storing the time series data, the spatio-temporal data management method including steps of:

segmenting, by the processor, the spatio-temporal region in time and space to generate a plurality of spatio-temporal segments;

assigning, by the processor, in consideration of temporal and spatial proximity of the plurality of spatio-temporal segments, identifiers for uniquely identifying the plurality of spatio-temporal segments, each of the identifiers being expressed with a one-dimensional integer value, wherein;

the identifiers of a first set of values that are smaller than a second set of values are assigned to spatio-temporal segments of a first period of time that is older than a second period of time to which the identifiers of the second set of values are assigned, and

for the spatio-temporal segments of an identical period of time, the identifiers of close values are assigned to spatio-temporal segments that are close in spatial distance; and

determining, by the processor, an arrangement of the time series data such that pieces of data of spatio-temporal segments that are close in the assigned identifiers are arranged close on the storage device.

8. The spatio-temporal data management method according to claim 7, including a step of associating, by the processor, time series data on a boundary of each of the plurality of spatio-temporal segments with the each of the plurality of spatio-temporal segments.

9. The spatio-temporal data management method according to claim 8, including a step of generating, by the processor, the time series data on the boundary of the each of the plurality of spatio-temporal segments by linear interpolation.

10. The spatio-temporal data management method according to claim 7,

wherein the time series data includes grid time series data including at least one piece of data in the plurality of spatio-temporal segments, and point time series data including at least one spatial coordinate in the plurality of spatio-temporal segments, and

wherein the spatio-temporal data management method includes steps of:

assigning, by the processor, one of a common identifier and correlated identifiers to the grid time series data and the point time series data; and

specifying, by the processor, the one of the common identifier and the correlated identifiers to search the grid time series data and the point time series data in association with each other.

11. The spatio-temporal data management method according to claim 7, including a step of searching, by the processor, the time series data in a first determination step and a second determination step,

wherein in the first determination step, the processor calculates identifiers of spatio-temporal segments satisfying search conditions of time and space, and extract the spatio-temporal segments corresponding to the calculated identifiers as result candidates, and

wherein in the second determination step, the processor matches the time series data associated with the spatio-temporal segments extracted as the result candidates and the search conditions, to thereby generate search results.

12. The spatio-temporal data management method according to claim 11,

wherein data of the plurality of spatio-temporal segments includes a maximum value and a minimum value of the time series data within the plurality of spatio-temporal segments, and

wherein the first determination step includes a step of:

comparing, by the processor, search conditions of the time series data with at least one of the maximum value and the minimum value of the time series data; and

extracting, by the processor, spatio-temporal segments which correspond to the calculated identifiers and satisfy the search conditions of the time series data as the result candidates.

13. A non-transitory machine-readable storage medium, containing at least one sequence of instructions for controlling a computer system for managing time series data associated with a spatio-temporal region, the computer system including a processor for executing a program, a memory for storing the program, and a storage device for storing the time series data, the instructions that, when executed, causes the computer system to:

segment the spatio-temporal region in time and space to generate a plurality of spatio-temporal segments;

assign, in consideration of temporal and spatial proximity of the plurality of spatio-temporal segments, identifiers for uniquely identifying the plurality of spatio-temporal segments, each of the identifiers being expressed with a one-dimensional integer value, wherein;

the identifiers of a first set of values that are smaller than a second set of values are assigned to spatio-temporal segments of a first period of time that is older than a second period of time to which the identifiers of the second set of values are assigned, and

for the spatio-temporal segments of an identical period of time, the identifiers of close values are assigned to spatio-temporal segments that are close in spatial distance; and

determine an arrangement of the time series data such that pieces of data of spatio-temporal segments that are close in the assigned identifiers are arranged close on the storage device.