KR100672986B1 - System for constructing the compact-type GIS engine and spatial database for mobile data terminal - Google Patents

Abstract

The present invention provides a system for building a compact geographic information system engine and a spatial database for a mobile data terminal for power distribution field work processing.

To this end, the present invention provides a compact geographic information system engine comprising an interface manager, a loader, an object manager, a layer manager, a metadata manager, a query processor, and a spatial index manager; Smallworld database of distribution geographic information system drawing server which is distribution system and power facility information database; An extraction processor for selecting an object to be extracted by the user from the small world database and extracting the extracted object into layer-specific DXF files; In consideration of the capacity, performance and processing speed of the mobile data terminal, it selects only the required layers and filters the objects, redefines them with interest group layers defined in the layer manager, and creates intermediate temporary files with each layer number. A spatial object filtering and spatial format conversion processor; An API manager for providing an interface for interworking between a compact geographic information system engine and an on-site business application program; Spatial and non-spatial databases for mobile data terminals constructed through spatial object filtering and spatial format conversion processors are constructed from DXF files extracted in units of layers by the extraction processor.

Therefore, the present invention is a compact geographic information system engine and spatial database system that implements the power distribution information and power equipment information used in the office in the field without using a separate wireless communication network, so that the efficiency of field work processing It has the effect of improving the performance and productivity of work, and it can solve the inaccuracy and hassle of work processing using paper document drawings.

Description

System for constructing the compact-type GIS engine and spatial database for mobile data terminal}

1 is a system configuration diagram for explaining a compact geographic information system engine and a spatial database construction according to the present invention;

2 is a diagram illustrating the types of spatial objects;

3 is a view showing a storage structure of a POINT object;

4 is a view showing a storage structure of a polyline object;

5 is a view showing a storage structure of a polygon object.

6 is a view showing a storage structure of a text object;

7 is a diagram showing a storage structure of non-spatial information;

8 is a diagram illustrating a meta information storage structure of an object;

9 is a diagram illustrating a meta information storage structure of a layer;

10 is a view showing a map area meta information storage structure;

11 is a view showing types and styles of layers;

12 is a diagram illustrating division of accumulation;

Fig. 13 is a diagram showing the accumulation setting for each layer.

<Explanation of symbols for main parts of drawing>

1 --- compact geographic information system engine,

2 --- Smallworld database,

3 --- Export handler,
4 --- Drawing Exchange Format (DXF) file,

5 --- spatial object filtering and spatial format conversion handler,

6 --- Application Program Interface (API) Manager,

7 --- spatial database for mobile data terminals,

8 --- nonspatial (property) database for mobile data terminals,

10 --- interface manager, 20 --- loader,

30 --- object manager, 40 --- layer (phase) manager,

50 --- metadata manager, 60 --- query handler,

70 --- Spatial Index Manager.

The present invention relates to a system for building a compact geographic information system (GIS) engine for mobile data terminals (MDT) and a spatial database for processing power distribution field work.

Recently, as the wireless Internet market grows rapidly with the development of wireless communication networks, interest in services based on mobility is increasing. In addition, as mobile phones, portable digital assistants (PDAs) and mobile data terminals (MDTs) are becoming more common, services based on global positioning systems (GPS) are becoming more common. . In accordance with these changes, the use of location information in a mobile Geographic Information System (GIS) environment based on a wireless terminal supporting mobility has attracted great interest, and in order to efficiently provide such services, a location based service (LBS) Location based service technology development is needed.

Mobile processing type GIS engine and application development technology, which is one of the core technologies of location-based services, should be developed considering the characteristics of the terminal depending on the computing environment of the mobile terminal. In particular, it must be designed and implemented after careful consideration and testing of limited characteristics such as low processing speed, low memory space, small screen, and wired / wireless communication environment. In addition, since it is developed and operated in a dedicated operating system, when the specifications of the mobile client are different, a lot of customization is involved, such as adjusting the resolution as well as the CPU.

Recent research and development have all the geographic information in the server and web services to mobile clients. Mostly, the speed of this method depends on the wireless network performance and quality. There are some commercially available products such as vehicle navigation, vehicle control, and logistics location tracking in the form of storing and servicing spatial objects in mobile terminals, but each has a separate data format because it is not standardized. Because of the service structure, it is very difficult to add the spatial objects and power equipment attribute information of a large capacity distribution system.

With the establishment of geographic information system in the country, KEPCO is promoting the establishment of geographic information system for each work environment in various electric power business areas such as transmission and transmission, environment, and power location selection. In particular, in the sales field, the field equipment information of the distribution system covering the processing and the ground is constructed as a database in the form of a digital map that can be used in the geographic information system to effectively perform distribution tasks including design, construction, completion, and facility management. Although it has been developed to do so, there is no mobile geographic information system that can see the same type of distribution system in the office used in the office. Currently, the office prints out pieces of work area as paper documents in the office. I use it. Although it is applied to some field work such as field survey and meter reading by using PDA, most of them use the fragmented drawing by management section extracted from drawing server and download the minimum amount required for work by cycle due to the limited storage capacity of mobile terminal. I take it and use it.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described aspects. A form that can be used in a mobile data terminal by extracting, selecting, converting, indexing, and compressing distribution system and facility property information connected between spatial objects of a business unit in a drawing management database server By building a spatial database and developing a compact geographic information system engine that takes into account the characteristics and processing performance of mobile data terminals, the distribution system and facility attribute information used in the office can be used in the workplace and interworked with the geographic information system. Its purpose is to provide a system for building a compact geographic information system engine for mobile data terminals and a spatial database that can be used in various applications for power distribution field work by providing APIs.

A compact geographic information system engine for mobile data terminals and a system for constructing a spatial database for power distribution field work processing according to the present invention for achieving the above object, the interface for graphic processing according to the user's events Manager, a loader that loads data into main memory, an object manager that manages four spatial objects of points, text, polylines, and polygons to represent spatial data, a layer manager that manages layers, a set of spatial objects, A compact geographic information system engine consisting of a metadata manager that manages information about objects and information about tables, a query processor that processes requested queries through an interface manager, and a spatial index manager to efficiently retrieve spatial data; ; Smallworld database of a distribution geographic information system drawing server, which is a distribution system and a power equipment information database constructed with GE Smallworld GIS Tool in a Windows 2000 server environment; An extraction processor for selecting an object to be extracted by the user from the small world database and extracting the extracted object into layer-specific DXF files; In consideration of the capacity, performance and processing speed of the mobile data terminal, it selects only the required layers and filters the objects, redefines them with interest group layers defined in the layer manager, and creates intermediate temporary files with each layer number. Spatial object filtering and spatial format conversion processor; An API manager for providing an interface for interworking between a compact geographic information system engine and an on-site business application program; Spatial and non-spatial databases for mobile data terminals constructed through spatial object filtering and spatial format conversion processors are constructed from DXF files extracted in units of layers by the extraction processor.

(Example)

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is a system configuration diagram illustrating the construction of a compact geographic information system engine and a spatial database for a mobile data terminal according to the present invention. The present invention is largely a compact geographic information system engine (1) and a distribution geographic information system drawing server. Smallworld database (2), extraction processor (3) by user's object selection in small world database, drawing exchange format (DXF) files (4) extracted by layer, spatial object filtering And a spatial format conversion processor 5, an API manager 6 linked with a geographic information system engine, a spatial database 7 for mobile data terminals, and a non-spatial (attribute) database 8 for mobile data terminals.

The compact geographic information system engine 1 includes an interface manager 10, a loader 20, an object manager 30, a layer (phase) manager 40, a metadata manager 50, a query processor 60, and It is composed of seven components of the spatial index manager 70.

The interface manager 10 is a module for providing an interface with a geographic information system engine to the user and is responsible for graphic processing according to the user's event. The query is forwarded to the query processor 60 as needed to access the spatial database 7 and the non-space database 8 and present the results to the user. The screen supports moving mode and object selection mode, and provides interfaces such as zooming in, zooming out, moving between scales, moving indexes, and viewing facility properties.

In addition, the loader 20 functions to load space, non-space, and position data into the main memory whenever necessary. The engine's development environment is based on Windows CE. Memory is divided into storage memory and program memory. The storage memory is used for data storage like a disk of a PC, and the program memory is used when executing a program. The loader loads necessary data such as a spatial index file and an index diagram to be displayed on the initial screen when the GIS engine is driven, and interacts with the spatial index manager 70 to page the storage memory and the program memory in units of 4 KBytes.

In addition, the object manager 30 manages four spatial objects, such as point, text, polyline, and polygon, to represent spatial data.

In addition, the layer manager 40 manages a layer, which is a collection of one or more spatial objects. One layer may represent roads, another layer may represent power lines, and another layer may represent topological relationships.

In addition, the metadata manager 50 manages information about objects and tables. Metadata is not real data, but provides a list of useful information about the data to help users acquire and use the data. Meta data is provided along with actual data by listing map area coordinate information, object and layer classification information, data production and process information, and business information.

In addition, the query processor 60 processes the requested query through the interface manager 10. This geoinformation engine update is done on the server side after the initial DXF data filtering and conversion, and there is only a search query on the mobile client. Processing a query involves loading and retrieving huge amounts of data logically and physically into memory. If you do not process this large amount of data efficiently, the performance of the system will be significantly reduced.

Moreover, the spatial index manager 70 is used to search spatial data efficiently, and uses an R-tree to search spatial data.
The seven components of the GIS engine 1 are individually configured and are organically combined and processed according to user events. When the user requests a specific event such as zoom in, zoom out, or move, the interface manager 10 recognizes the event and transmits the event name to the query processor 60. The query processor 60 requests the metadata manager 50 to receive the map area coordinates and the information on the classification of the object and the layer. The query processor 60 generates a query word, and if necessary, queries the spatial index manager 70 and non-space. The data is retrieved from a non-spatial (attribute) database 8. The spatial index manager 7 searches the spatial index to find the corresponding object in the spatial database 7 to search the spatial object of the queried area. When the retrieved spatial object and the non-spatial data are delivered to the loader 20 and loaded into the memory, the object manager 30 classifies the object by the object type and delivers a set of objects to the layer manager 40. The layer manager 40 determines the topological relationship of layers, which is a set of objects, and whether or not to display them on the screen, and transmits them to the interface manager 10. The interface manager 10 draws layers on the screen and expresses attribute information. .

The small world database 2 is a distribution system and power equipment information database built with the GE Smallworld GIS Tool in a Windows 2000 server environment.

In addition, the extraction processor 3 selects objects to be extracted by the user from the small world database 2 and extracts them into DXF files 4 in units of layers. The extraction processing method scans all geometry in the selected target area when the target object and business area to be extracted are selected in the small world. While scanning, each geometry is read into memory by geometry type and facility layer type, and then the DXF layer, DXF color, DXF block name, and DXF line type are set and returned for each scanned geometry. At this time, the basic equipment objects are created as DXF layer as the object name, and the objects related to the national basic map are extracted by subdividing the layers for the filtering process for the mobile data terminal drawing output. The returned DXF attribute is stored in the target DXF file along with the coordinates of that geometry.

In addition, the spatial object filtering and spatial format conversion processor 5 selects an essential layer and filters an object in consideration of the capacity, performance, and processing speed of the mobile data terminal, and the interest defined by the layer manager 40. Redefine the group layer and create an intermediate temporary file with each layer number. This temporary file is read to create spatial objects and indexes for use in mobile data terminals. Filtering is mainly performed on the national base map, which is divided into layers in detail and has a large amount of spatial data. For example, highway layers, roads, streets, roads, roads, etc. should be used in mobile data terminals, but construction roads, tunnel roads, road outlines, and cableways should be excluded.

Spatial index generation uses R * -tree and is modified to be suitable for mobile data terminal by modifying general algorithm. First, to insert an object, the tree is searched starting from the root from top to bottom. At each level, you might find a node with a dr (directory rectangle) containing the object's minimal bounding box (mbb) to get a node subtree or not find that node. The node selects a node whose expansion of node dr is minimized. The process is repeated until the terminal is reached. If the node terminal is not full, a new entry [mbb, oid] is added to the page associated with the terminal node. If the terminal node dr is to be expanded, it must be updated with the new value of the corresponding dr in the parent node. . This means that the parent's dr is expanded. Therefore, terminal node expansion increases the tree, and the worst case is that the tree is extended to the root. If the inserted object terminal node l becomes full, separation occurs. A new terminal node l 'is created, and an M + 1 entry is distributed between l and l'.

The separation of terminal nodes sorts the entries for each dimension according to the lower limit (m) and the upper limit (M), and then k (k = 1, ...., (M to divide M + 1 entries into two groups). The -2m + 2)) th distribution distributes M-2m + 2, with the first group containing the first (m-1) + k entries, the second group containing the remaining entries, and then Calculate the sum S of the perimeters. Select the dimension where S is the minimum as the dividing axis, and choose the distribution method that minimizes the overlap for the selected dimension. If the overlap size is the same, the distribution method with the smallest area is chosen.

In addition, the API manager 6 provides an interface for interworking the compact geographic information system engine 1 with the field business application. Therefore, the application program can search for and move to a specific facility, select a specific spatial object or area, and utilize various necessary functions. In addition, by using the spatial coordinate system received by the GPS receiver to determine the current location of the mobile data terminal, and provides a navigation support API that specifies the destination (equipment object).
Extraction and conversion from the small world database 2 are processed sequentially. The extraction processor 3 extracts the object to be extracted from the small world database 2 into respective DXF files. After the extraction is completed, the spatial object filtering and spatial format conversion processor (5) is automatically executed to filter out only the required layers to be expressed in the mobile terminal to create a temporary file, and then read the temporary file to read the spatial object and spatial index for the mobile terminal. A spatial database 7 is generated through a space format conversion process to generate a non-spatial data, and a non-spatial (attribute) database 8 is generated and stored. The generated spatial database 7 and non-spatial (attribute) database 8 are installed in the mobile terminal together with the compact geographic information system engine 1 and the API manager 6 to operate. As described above, the compact geographic information system engine 1, the spatial database 7 and the non-spatial (attribute) database 8 are organically combined and processed according to the user event. The API manager 6 receives the spatial object representation request from the field business application program such as electric fault recovery and instantaneous inspection, and delivers the data to the interface manager 10 of the compact GIS engine 1 for application. The program and the compact geographic information system engine (1) serves as an intermediary to operate in conjunction with. In addition, the position coordinates received from the GPS receiver are received and transmitted to the interface manager 10 of the compact geographic information system engine 1 to express the current position of the vehicle.

2 illustrates four types of spatial objects for representing spatial data in the compact geographic information system engine according to the present invention. The POINT and TEXT spatial data types have a fixed length and are primarily used to represent position data. POLY_LINE and POLYGON are used to represent spatial data and are processed through a variable length processing method because they are variable length data.

FIG. 3 shows the storage structure of the POINT object, FIG. 4 shows the storage structure of the POLYLINE object, FIG. 5 shows the storage structure of the POLYGON object, and FIG. 6 shows the physical storage structure of each object. The storage structure of POINT object, POLYLINE object, POLYGON object, and TEXT object is allocated 4 bits to the code number for classifying the layer and the object type for classifying the type of spatial object, and then the data of each object is stored. . In POLYLINE and POLYGON, X and Y coordinates are stored as many as the number stored in the Point Count field. 7 is a storage structure of non-spatial (attribute) information and is stored as a set of attribute information separated by an identifier and a ';' character.

FIG. 8 is a meta information storage structure of an object, FIG. 9 is a meta information storage structure of a layer, FIG. 10 is a map area meta information storage structure, and meta data is provided together with actual data when necessary.

FIG. 11 illustrates layer names, object types, and styles to be displayed on a screen managed by a geographic information system engine, and FIG. 12 is defined to enable step-by-step enlargement and reduction by dividing the scale into 10 steps. Like the expression setting according to the scale of each layer, it is determined whether the layer is displayed on the screen according to the scale of the screen. Therefore, only objects marked with “○” are imaged on the screen when they are at that scale.

The topology information of a layer is not an essential element of GIS data but must exist for spatial analysis. The topological structure refers to the spatial relationship of spatial shapes of points, lines, and planes. That is, spatial relationship information between various spatial shapes is provided as adjacency, continuity, area definition, and the like. Doing. In this GIS engine, for example, the topology is a region on one power line, which region is on the left, which region is on the right, and which other line is connected at the end of one power line, and also the line. It is a continuity that tells where the starting and ending poles of are. In addition, although it appears to be a closed region to the user's eyes, it is the region information that distinguishes one or two dimensions, whether it is a closed line or an area. Through this topology information, spatial analysis is possible, such as finding buildings adjacent to a track or finding the shortest distance switch and load point along a track in a pole.

As described above, according to the present invention, as a compact geographic information system engine and a spatial database system implemented so that the distribution system and power equipment information used in an office can be seen in the same form on the site without using a separate wireless communication network. It has the effect of improving work efficiency and work productivity, and can solve the inaccuracy and hassle of work processing using paper document drawings.

In addition, it is possible to always see the entire drawing on the site, not the engraving drawing, so as to grasp the entire distribution system and facility information, and to quickly and accurately carry out work, and to search the current location and the destination using the navigation function through the GPS receiver interworking interface. It is easy to find the location of the facility, and it is the basis for supporting various field work processing such as power equipment breakdown and instant inspection, site design and supply plan review, field survey, meter reading and instrument work in connection with the compact geographic information system engine. A system can be provided.

Claims (3)

A system for building a compact geographic information system engine for mobile data terminals and a spatial database for power distribution field work, The interface manager 10 in charge of graphics processing according to the user's event, the loader 20 for loading data into the main memory, the point (text), polyline (polyline), An object manager 30 that manages four spatial objects of a polygon, a layer manager 40 that manages a layer that is a set of the spatial objects, and a meta that manages information about the object and a table A compact geographic information system engine comprising a data manager 50, a query processor 60 for processing a query requested through the interface manager 10, and a spatial index manager 70 for efficiently searching for spatial data ( 1) and; Smallworld database (2) of the distribution geographic information system drawing server, which is a distribution system and power equipment information database constructed with GE Smallworld GIS Tool in a Windows 2000 server environment; An extraction processor (3) which selects objects to be extracted by the user from the small world database (2) and extracts them into DXF files (4) in units of layers; In consideration of the capacity, performance, and processing speed of the mobile data terminal, only an essential layer is selected and an object is filtered. The object is redefined as an interest group layer defined by the layer manager 40, and each layer number is intermediate. A spatial object filtering and spatial format conversion processor 5 for generating a temporary file; An API manager (6) for providing an interface for interworking with the compact geographic information system engine (1) and field work application programs; The spatial and non-spatial databases (7, 8) for mobile data terminals constructed by the spatial object filtering and spatial format conversion processor from the DXF files extracted in units of layers by the extraction processor (3) Compact geographic information system engine and spatial database construction system for mobile data terminals. The method of claim 1, The spatial and non-spatial databases 7 and 8 for the mobile data terminal select the target object and the business area to be extracted from the small world database 2 of the distribution geographic information system drawing server, and all geometries within the selected target area. While scanning, extract per-area geometry, set per-geometry layers, convert per-layer geometry to a DXF file, output, filter detail layers, redefine them with interest group layers, and create R * -tree spatial indexes. A compact geographic information system engine and a spatial database construction system for mobile data terminals, characterized in that for building. The method of claim 1, Types of objects consisting of spatial objects and non-spatial information of the point, text, polyline, and polygon, and metadata about storage structures, objects, layers, and map areas of each object. Compact geospatial system engine for mobile data terminals, characterized in that the storage structure of the layer, the classification and application of layers, the object to be displayed on the screen, the style to be displayed on the screen, the division of the scale of 10 steps, the representation according to the scale of each layer; Spatial database construction system.

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