KR20020053977A - Method and System for Web Geographical Information to Service Geographical Information of The Large Scale Vector Form - Google Patents

Abstract

PURPOSE: A large-sized vector type geographic information system and method is provided to enable a user to make an SQL(Structured Query Language) query, to perform a spatial operation, and to generate dynamically a desired map. CONSTITUTION: The system comprises a web client(110), a main web server(120), a database agent(130) and geographic information servers(141-141n). The web client(110) includes a JAVA applet program executable over a web browser. The web client(110) accesses the main web server(120), then accesses a desired one among the geographic information servers(141-141n) with a help of the database agent(110) and downloads the JAVA applet program from the accessed geographic information server. The database agent(130) manages the geographic information servers(141-141n) accessible by the main web server(120), and sets a connection between the web client(110) and the geographical information servers(141-141n) for enabling the web client to obtain geographic information on a desired area. The main web server(120) checks which area the web client wants to receive. The geographical information servers(141-141n) offer vector based geographic information to the web client(110).

Description

Web geographic information system and method for serving geographic information in the form of large-scale vectors {Method and System for Web Geographical Information to Service Geographical Information of The Large Scale Vector Form}

The present invention relates to a web geographic information system that improves database system access speed and network transmission speed, and a method and a recording medium for recording a program for realizing the method. The present invention relates to a web geographic information system for a web geographic information service for servicing geographic information in a large vector format, and a method and a computer readable recording medium for realizing the method.

Until now, web geographic information systems have provided image based geographic information to web service users, not vector based geographic information.

The image-based web geographic information system is configured in such a way that the server system generates a fixed size image map and transmits the image map to the web client system. Therefore, most server systems firstly process the area query of the geographic information required by the web client, secondly access the file system to read the result information of the area query process, and thirdly, the vector format from the file system. It consists of three parts that convert the resulting information into a fixed-size image map and send it to the client system. In particular, the web geographic information system using the image map uses the geographic information stored in most file systems rather than the database system in order to quickly read the geographic information desired by the user.

Such an image map method can perform a web service relatively faster than a vector map method, but has some problems as follows.

First, the image map method cannot provide dynamic mapping functions such as zooming in, zooming out, moving the map, and generating thematic map within the client system.

Second, the image map method cannot select a desired object or perform a spatial operation on a geographic information map.

Third, most image map methods store geographic information in the file system, so they cannot process various user queries such as SQL (Structured Quary Language).

Nevertheless, the reason why such an image map method is mainly adopted as a web geographic information system is that two priorities must be solved in order to support a large amount of vector geographic information in a web environment. The first is to improve access to geographic information in database systems that are significantly slower than file systems. Second, unlike image maps of fixed size, the network transmission speed of vector geographic information whose data amount changes drastically depending on the map type must be improved.

The present invention has been proposed to solve the above problems, and can efficiently access a large amount of geographic information stored in a database system in a web environment, and efficiently perform geographic information in a vector format over a network. By presenting a method that can be transmitted, users can query various Structured Query Language (SQL) queries, perform spatial operations, and dynamically create a map that users want by using a vector map method instead of an image map method. It is an object of the present invention to provide a web geographic information system and a method for supporting a service that can be performed, and a computer-readable recording medium for realizing the method.

1 is a configuration diagram of an embodiment of a web geographic information system according to the present invention.

2 is a configuration diagram of an embodiment of a spatial engine configuring a geographic information server according to the present invention.

3 is a flow chart of an embodiment of a geographic information service method using a web geographic information system according to the present invention.

* Explanation of symbols for the main parts of the drawings

110: web client 120: the main web server

130: database agent 141 ~ 14n: geographic information server

151 ~ 15n: Web Server161 ~ 16n: Space Engine

171 ~ 17n: Database

An apparatus of the present invention for achieving the above object is a web geographic information system for serving geographic information, comprising: a web client for performing a web geographic information service; A main web server for checking geographic information requested by the web client; Database management means for establishing a connection with a geographic information service requested by the web client checked by the main web server; And a plurality of geographic information servers for performing the geographic information service set by the database management means.

On the other hand, the method of the present invention, geographic information service method applied to a web geographic information system, comprising: a first step of being connected to a web client; A second step of determining whether to perform a spatial operation; As a result of the second step, if the spatial operation is performed, performing a spatial operation after performing the spatial operation and performing data retrieval, obtaining data from the data manager, and transmitting the information to the web client; A fourth step of determining whether to perform a spatial search operation if the spatial operation is not performed as a result of the determination of the second step; And as a result of the determination of the fourth step, when the spatial search is performed, the spatial search is performed, data is obtained through the data manager, and the information is transmitted to the web client. If the spatial search is not performed, the data is transmitted through the data manager. And obtaining a fifth step of transmitting the information to the web client.

On the other hand, the present invention, a web geographic information system having a large processor, the first function connected to the web client; A second function of determining whether to perform a spatial arithmetic operation; A third function of performing a spatial operation after performing a spatial operation, performing a spatial retrieval operation, obtaining data from a data manager, and transmitting information to the web client as a result of the determination of the second function; A fourth function of determining whether to perform a spatial search operation if the spatial operation is not performed as a result of the determination of the second function; And as a result of the determination of the fourth function, when the spatial search operation is performed, the spatial search operation is performed, the data is obtained through the data manager, and the information is transmitted to the web client. A computer readable recording medium having recorded thereon a program for realizing a fifth function of obtaining and transmitting information to the web client.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an embodiment of a web geographic information system according to the present invention.

As shown in FIG. 1, the web geographic information system includes a web client 110 for performing a web geographic information service, a main web server 120 for checking geographic information to be used by the web client 110, A database agent 130 that establishes a connection with the geographic information servers 141 to 14n requested by the web client 110 checked by the main web server 120, and performs a geographic information service set by the database agent. Geographic information servers 141-14n.

The web client 110 refers to an entire homepage for a web geographic information service including a Java applet program executed on Internet Explorer or Netscape. The web client 110 first accesses the main web server 120, and then accesses the geographic information server 141 ˜ 14n to which the user wants to connect with the help of the database agent 130. In fact, the Java applet program for performing the web geographic information service is downloaded to the web client 110 by connecting to the geographic information server (141 ~ 14n).

The database agent 130 manages the geographic information servers 141 to 14n that can be accessed from the main web server 120, and the web clients 110 connected to the main web server 120 desire their own. The database agent 130 establishes a connection between the web client 110 and the geographic information servers 141 to 14n in order to acquire a geographic information service of the region.

The main web server 120 is a server to which the web clients 110 who wish to use the vector-based web geographic information service for the first time provide basic homepage information of the web geographic information system, and the web clients 110 serve geography in a certain region. Check if you require information. Of course, the geographic information servers 141 to 14n to be connected later vary according to regions selected by the web clients 110.

The geographic information servers 141 to 14n actually perform vector-based geographic information services to the web clients 110.

The geographic information server 141 to 14n includes a web server 151 to 15n, a spatial engine 161 to 16n, and a database system 171 to 17n, and plays a key role in supporting an efficient service of vector-based geographic information. Do this.

Through the database agent 130, the web clients 110 are newly connected to the web servers 151 to 15n in the geographic information servers 141 to 14n, and also connected to the space engines 161 to 16n.

The web servers 151 to 15n in the geographic information servers 141 to 14n allow the web client 110 to perform a vector-based web geographic information service by transmitting a Java applet program to the web clients 110. Detailed configurations and functions of the space engines 161 to 16n will be described with reference to FIG. 2.

Databases 171 to 17n in the geographic information servers 141 to 14n store geographic information of a large amount of space and attributes and are connected through the space engines 161 to 16n.

2 is a configuration diagram of an embodiment of a spatial engine configuring a geographic information server according to the present invention.

As shown in FIG. 2, the spatial engine 200, which plays a key role in the geographic information servers 141 ˜ 14n, is connected to the web client 270 in a socket manner to transfer spatial information and attribute information to the web client. The spatial engine broker 210 to transmit, the spatial operation processor 220 to perform a spatial operator, the spatial index manager 230 to perform a spatial search function, and the data manager to obtain data from a database managing spatial information and attribute information. 240, and a memory database 250 that stores spatial information in binary format.

A function that the space engine broker 210 must provide is to first connect to a Java applet program (web geographic information service program) of the web client system 270 in a socket manner. Second, the spatial information in the memory database 250 and the attribute information in the physical database are transmitted to the web geographic information service program of the web client 270. Here, since the spatial information stored in the memory database 250 is stored in a binary vector format, the spatial engine broker 210 transmits the spatial information in binary format. The spatial operation processor 220 performs the space operators "Within", "Contain", "Intersect", and "Touches" that the general space engine has.

The spatial index manager 230 also provides spatial search functions such as match, cross, include, and embedded search that the general spatial engine has. However, the data manager 240 performs a different function from the data manager provided by the general spatial engine for efficient vector geographic information transmission. A typical data manager reads both spatial and attribute information from a physical database. Whether processing a user's query or performing a spatial search or spatial operation, the geospatial results are always obtained from tables in the physical database. However, accessing a large amount of geographic information stored in a hard disk through a database slows down the speed of reading data due to the hard disk access speed and the performance of the database system. If a large amount of time is spent reading data from a database, it is difficult to perform vector-based geographic information services on the web even if the data transfer time is over a network. Therefore, in the present invention, a new data manager 240 is constructed rather than the conventional method. The spatial engine 200 generates a memory database 250 that extracts spatial information from a physical database and stores the spatial information in a binary format on the main memory when it is first started by the geographic information server.

The memory database 250 first stores binary spatial information for each layer, and has two columns of an identifier (ID) column and a spatial information column. It must also be sorted in ascending order using the identifier column. This identifier (ID) information is the same information as the identifier (ID) information for the spatial objects that are subsequently given as a result of the spatial search and spatial operation, allowing the search and operation results to be accessed in memory directly.

As such, the data manager 240 of the present invention quickly obtains a desired result by accessing a very fast memory database 250 without accessing a physical database to obtain result spatial information after a spatial search or a spatial operation. Send to client 270. This approach consumes more than 70% of the time it takes to read the data, compared to more than 70% of the time it takes to read the data and 30% of the time to transfer the data. Minimize the effect. Here, of course, attribute information is obtained from a physical database. However, from the user's point of view, the web geographic information service is performed by first contacting the map on the screen and then requesting the attribute information on the spatial object required in the map. In other words, a large amount of spatial information is required to display a map on the screen. However, since the attribute information for a few spatial objects that are desired is not a large amount, the attribute information does not need to be processed in large quantities. Reading information from the database does not matter at all.

3 is a flowchart illustrating an embodiment of a geographic information service method using a web geographic information system according to the present invention.

As shown in FIG. 3, first, the web client 300 accesses the main web server of the web geographic information service through a web browser such as Explorer or Netscape (302).

The web client 300 connected to the web server provides the database agent 304 with information about a geographic information server (eg, Daejeon geographic information or Seoul geographic information) that the client wants to use. The database agent 304 then accesses the selected geographic information server using the web client's information (306), and connects the spatial engine broker 308 and the web client system 308 of the geographic information server.

The space engine broker 308 connected to the web client 300 processes the client user's request and first checks whether the user requests a spatial calculation task (310).

As a result of the checking, when the spatial calculation task is required, the spatial engine broker 308 requests the spatial computation processor 312 to perform the spatial computation task (314), and the spatial computation processor 312 performs the spatial computation. In order to retrieve the required candidate spatial object, the spatial index manager 316 requests a spatial search operation to extract candidate data from a database, and the spatial index manager 316 performs a spatial search operation (318).

When the spatial search task is completed, the data manager 320 reads the spatial and attribute data from the database.

As a result of the check 310, the space engine broker 308 checks whether the user's request is a simple space search task, if it is not a spatial operation task (332).

As a result of the check 332, in the case of the spatial search task, the spatial index manager 316 performs the spatial search task in the same manner as in the spatial operation task (318) and obtains data through the data manager 320.

If the result of the check 332 is not a spatial search operation, the data manager 320 directly requests data and attribute data to obtain data.

Note that the role of the data manager 320 is noted here. The data manager 320 may provide spatial information and attribute information. First, it is checked whether the user's request includes a spatial information request (322).

As a result of the check, when the user requests the spatial information, the data manager 320 does not request the spatial information from the physical database 330 but requests the spatial information from the memory database 324 stored in binary format. Of course, the attribute information is obtained from the physical database 330 because it is not stored in the memory database 324.

The spatial and attribute information obtained from the physical database 330 and the memory database 324 is compressed in a binary format through the spatial engine broker 326 to be transmitted to the web client 328, and the basic web geographic information service is terminated.

As described above, the method of the present invention may be implemented as a program and stored in a recording medium (CD-ROM, RAM, ROM, floppy disk, hard disk, magneto-optical disk, etc.) in a computer-readable form.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be apparent to those of ordinary knowledge.

As described above, the present invention has an effect of supporting a vector-based web geographic information service of a higher level than an image-based web geographic information service in a short time.

In addition, the present invention has the effect of easily constructing a web geospatial information system of dynamic mapping that supports spatial operations and accommodates various needs of users as well as the existing web geospatial services of static mapping level.

Claims (7)

In the web geographic information system for serving geographic information, A web client for performing a web geographic information service; A main web server for checking geographic information requested by the web client; Database management means for establishing a connection with a geographic information service requested by the web client checked by the main web server; And Multiple geographic information servers for performing the geographic information service set by the database management means Web geographic information system comprising a. The method of claim 1, The geographic information server, A web server for connecting with the web client; A spatial engine for transmitting geographic information to the web client; And Storage means for storing geographic information of space and property Web geographic information system comprising a. The method of claim 2, The space engine, A spatial engine broker connected to the web client in a socket manner to transmit spatial information and attribute information to the web client; A spatial operation processor connected to the spatial engine broker to perform a spatial operator; A spatial index manager connected to the spatial engine broker and the spatial operation processor to perform a spatial search function; A database for storing spatial information and attribute information; A memory database unit connected to the spatial engine broker unit and the spatial index management unit to store spatial information in binary format; And A data management unit for managing data of the database and the memory database Web geographic information system comprising a. The method of claim 3, wherein The memory database unit, Extract spatial geographic information for each layer from the physical database, and use the binary information for spatial information and identifier (ID) as the default column, and sort them in ascending order based on the identifier (ID) column. Web geographic information system characterized by. In the geographic information service method applied to a web geographic information system, A first step of connecting with a web client; A second step of determining whether to perform a spatial operation; As a result of the second step, if the spatial operation is performed, performing a spatial operation after performing the spatial operation and performing data retrieval, obtaining data from the data manager, and transmitting the information to the web client; A fourth step of determining whether to perform a spatial search operation if the spatial operation is not performed as a result of the determination of the second step; And As a result of the determination of the fourth step, if the spatial search operation is performed, the spatial search operation is performed and the data is obtained through the data manager and the information is transmitted to the web client. If the spatial search operation is not performed, the data is transmitted through the data manager. A fifth step of obtaining and sending information to the web client Geographic information service method comprising a. The method of claim 5, The process of obtaining data from the data manager, A sixth step of determining whether to request a spatial information request; A seventh step of obtaining data from the memory database when the spatial information request is requested as a result of the determination of the sixth step; And An eighth step of obtaining data from a physical database if it is not a request for spatial information as a result of the determination of the sixth step Geographic information service method comprising a. In a web geographic information system equipped with a large processor, A first function of connecting with a web client; A second function of determining whether to perform a spatial arithmetic operation; A third function of performing a spatial operation after performing a spatial operation, performing a spatial retrieval operation, obtaining data from a data manager, and transmitting information to the web client as a result of the determination of the second function; A fourth function of determining whether to perform a spatial search operation if the spatial operation is not performed as a result of the determination of the second function; And As a result of the determination of the fourth function, when the spatial search operation is performed, the spatial search operation is performed, the data is obtained through the data manager, the information is transmitted to the web client, and when the spatial search operation is not performed, the data is transmitted through the data manager. A fifth function of obtaining and transmitting information to the web client A computer-readable recording medium having recorded thereon a program for realizing this.