• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.187-191
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• 2008

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. This thesis will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.4 s.27
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• pp.45-51
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• 2003

This study intended to extract the spatial data and attribute data from the images of terrestrial photographs to compile the digital map from the images using photogrammetric analysis. In this study, the plane map of present objective area was made using the single terrestial photographs and graphical method, and the spatial or attribute data for the facilities in the area was extracted. Also, it is concluded that the efficient techniques for acquiring spatial and attribute data of the building and road facilities in proper time for the concerning area were suggested.

• Journal of Cadastre & Land InformatiX
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• v.50 no.2
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• pp.221-235
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• 2020

The development and utilization of underground spaces are increasing as the use of land based on ground surface became limited due to rapid urbanization triggered by population growth and industrialization. Despite its merit of efficient use of limited land and space, it may contribute to occurrence of various disasters such as sinkholes and damage to underground facilities. After the sinkholes formed and occurred across the country in 2014, there has been an effort to establish Underground Space Integration Map containing 15 types of underground information. Still, there is an increasing demand to improve the quality of underground information stemmed from continuation of such events including the rupture of the hot water pipe in Goyang-si and the fire in the KT site in Ahyeon-dong, Seoul. Hereby, with the aim to improve the quality of Underground Space Integration Map, this study analyzes quality standards, regulations, and guidelines related to spatial data to improve quality inspection standards and methods included in the production rules for the Underground Space Integration Map. In particular, it suggests improvement plan for data quality management for pipe-type underground facilities, known as lifelines, which are essential part of daily life of the citizens, and the largest cause for accidents according to 15 types of underground information managed through the Underground Space Integration Map.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1253-1258
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• 2006

In the mobile vector map service environments, there are problems like as terminal resource shortage and transmission delay for the characteristics of large spatial data. For the normal mobile vector map services, some techniques are required to overcome the problems. Spatial data compression approach is one of the techniques to reduce the bandwidth and the waiting time at clients. However it also must be considered that the effect on total efficiency caused by the overhead of compression and restoration time. This thesis proposes two spatial data compression techniques. First approach is to get relative coordinates to first coordinate of each object. The other approach is to compute client coordinates before transmission. Through the implementation and experiments, proposed techniques are evaluated the compression effects and efficiency.

• Spatial Information Research
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• v.7 no.1
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• pp.39-48
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• 1999

A GRId-based Soil MOsture Routing Model(GRISMORM) which predicts temporal variation and spatial distribution of water balance on a daily time step for each grid element of the watershed was developed. The model was programmed by C-language which aims for high flexibility to any kind of GIS softwares. The model uses ASCII-formatted map data supported by the irregular gridded map of the GRASS(Geographic Resources Analysis Support System)-GIS and generates daily or monthly spatial distribution map of water balance components within the watershed. The model was applied to Ipyunggyo watershed(75.6$km^2$) ; the part of Bocheongchun watershed. Predicted streamflows resulting from two years(95 and 96) daily data were compared with those observed at the watershed outlet. The results of temporal variation and spatial distribution of soil moisture are also presented by using GRASS.

• Spatial Information Research
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• v.7 no.1
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• pp.147-153
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• 1999

Geological map and data are needed for land use planning, resources development, geological hazard prevention, environment protection and education, Since the nationwide geological database in Korea has not been constructed yet, there are many problems in using the geological map and data. There are many problems such a stratigraphy unestablishment, map conservation and edge matching in geological paper map. Therefore it is difficult to construct the geological map database, but the geological map database must be constructed as soon as possible as one of national thematic map. In this study, geological maps of pilot area such as Ansung geological map on a scale of 1:50,000, Busan on a scale of 1:250,000, Namchang on a scale of 1:25,000 and the whole Korean peninsula on a scale of 1:1,000,000 were designed and constructed to database using Geographic Information System(GIS). In addition the geological map management program was developed by GIS program. The digital geological maps were produced using the constructed geological database. The database could be of access through Internet World Wide Web(WWW) environment and be distributed in Compact Disk(CD).

• The Korean Journal of Ecology
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• v.19 no.5
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• pp.465-476
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• 1996

There are several environmental variables that may be influential to the spatial distribution of forest vegetation. To create a map of forest vegetation zone over southern part of Korean Peninsula, digital map layers were produced for each of environmental variables that include topography, geographic locations, and climate. In addition, an extensive set of field survey data was collected at relatively undisturbed forests and they were introduced into the GIS database with exact coordinates of survey sites. Preliminary statistical analysis on the survey data showed that the environmental variables were significantly different among the previously defined five forest vegetation zones. Classification of the six layers of digital map representing environmental variables was carried out by a supervised classifier using the training statistics from field survey data and by a clustering algorithm. Although the maps from two classifiers were somewhat different due to the classification procedure applied, they showed overall patterns of vertical and horizontal distribution of forest zones. considering the spatial contents of many ecological studies, GIS can be used as an important tool to manage and analyze spatial data. This study discusses more about the generation of digital map and the analysis procedure rather than the outcome map of forest vegetation zone.

• Spatial Information Research
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• v.20 no.2
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• pp.35-44
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• 2012

Recently, Web map service is actively accomplished in both private companies and public offices. As a platform, it exists variously from desktop to smartphone. The technology being used has a trend to develop continuously. Also, Web map system provides various open API for people who use geospatial service and data mashup. In this paper, RIA technology which is popularly used recently in web map service w ill be applied to introduce the functions different language map services are mostly using. Based on users' feeling about different web browser's speed, test and analysis have been accomplished. The result is that there are different characteristics according to different functions such as JavaScript, Silverlight, Flex. Actual test has been personally carried out on map service in Seoul GIS portal system. The comprehensive conclusion is that Silverlight has more outstanding function compared with other RIA techniques under the test environment.

• Journal of Korea Spatial Information System Society
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• v.11 no.3
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• pp.47-49
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• 2009

In this paper, we proposed a new algorithm for determination of many-to-many corresponding pairs between block-polygon sets from the national topographical map and the cadastral map in Korea Land Information System, caused by different abstraction and generalization rules of the two maps. Our proposed algorithm starts from an assumption that a block-polygon for a N:M pair should significantly overlap at least one block polygon of the counterpart group, and determines N:M pairs using an iterative updating and searching with this overlapping analysis. This iteration process is terminated when the N:M corresponding pairs satisfy our predefined 1:1 corresponding condition.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.827-835
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• 2010

Reliable forest statistics provides important information to meet the UNFCCC. In this respect, the national forest inventory has played a crucial role to provide the reliable forest statistics for several decades. However, the previous forest statistics calculated by administrative district has not provided spatial information in a small scale. Thus, this study focused on developing models to estimate an explicit spatial distribution of forest growing stock. For this, first, stand volume model by stand types was developed using National Forest Inventory(NFI) data. Second, forest type map was integrated with this model. NFI data were used to calculate plot-level stand volume and basal area. The stand types of NFI plot including the species composition, age class, DBH class and crown density class are very crucial data to be connected with forest type map. Finally, polygonlevel stand volume map was developed with spatial uncertainty map. Average stand volume was estimated at 85.7 $m^3$/ha in the study area, and at 95% significance interval it was ranged from 79.7 $m^3$/ha to 91.8 $m^3$/ha.