• Spatial Information Research
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• v.10 no.1
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• pp.45-59
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• 2002

The author argues that the current Government Information System for river water quality appears to be non-user friendly due to lack of the cartographic representation for the field monitoring data. Acknowledging these constraints, an operational, user-friendly information system has been developed by combining Internet technology with GIS. A digital map for water quality has been generated by overlaying monitoring data on existing cartographic data such as road, topography and administrative boundary etc. A user interface was designed to address the need to querry the large spatial databases by non-GIS and non-environmental experts. The system has been checked experimentally and enabled the users to querry data required simply. And detailed visual maps for water quality can be generated over large areas quickly and easily. A visual mapping system for water quality was developed by reframing the monitoring data as graphic symbols and it was ideally suited to exploring area-wide water quality at a user-friendly manner due to extensibility and scalability along the various survey points. This system based on Web GIS could be accessed anywhere if internet is available. It would play a crucial role in improving the quality of public information service if it is operationally introduced into the Government since the highly user-friendly interface provides a completely new means for disseminating information far water pollution in a visual and interactive manner to the general public.

• Journal of the Korean Geophysical Society
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• v.9 no.4
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• pp.387-395
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• 2006

Nowadays, various digital maps on a reduced scale were drawn in Korea including the topographic series of a nation. Though these digital maps are drawn and revised by using aerial photograph or satellite image, there are some problems that it is difficult to revise or renew the topography and natural feature immediately which changes frequently. As the countermeasures of these problems we use GPS accumbency method, which provides user with convenience and accumbency accuracy which is required to revise and renew digital maps. But acquiring correct position by using GPS only may cause not a few errors because of environmental effect of satellite signal errors that GPS obtains. Although accumulated errors which is the major problem of existing method was diminished owing to the position signal received from satellite which is about 20,183km above, the area that can not receives the signal is occur such as woods and high-rise buildings space. And because of the GDOP (Geometry Dilution of Precision) of GPS satellite and the periodically changing orbit of the satellite, the position calculating problems occur. For settlement of these problems and accurate position determination, DGPS (Differential GPS) is indispensably needed. So, in this study, by adapting Radio Beacon Receiver for marine position determination which is the most convenience method of DGPS methods, we elevated accuracy of modification and renewal of digital map and, having wide application in various measurements, proposed the rapid measurement method about widespread area. In this study, wewant to propose the work scheme of rapid modification and renewal of digital map by using Beacon GPS which is comparatively cheap of all the DGPS methods and which makes it possible to measure independently.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.1
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• pp.61-79
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• 2009

This study is for incompatible element contents of Perilla frutescens and Sesamum indicum from the Keumsan: biotite granite, phyllite and shale areas. In the soils, high elements are shown in the granite and phyllite areas, and in the areas of the Perilla frutescens. Positive correlations are distinctive within the granite for the Perilla frutescens, but the shale for the Sesamum indicum. These relationships can be explained with relative propositions of minerals containing the incompatible element. In the plants, high elements are shown in the shale and the Sesamum indicum are high in the comparisons of the same soil types. The low parts are mainly high. Regardless of the soil types, the lower and upper parts, respectively, are high in the Y, Zr and Rb contents for the Perilla frutescens, but, Ta, Nb, Th and U contents for the Sesamum indicum. Positive correlations are distinctive within plants of the phyllite. Comparing with the soil types, all HFS and Cs contents of the LFS in the plants are low with differences of several to hundred times, but high in the Sr contents with differences of several times. In the comparisons between plants and soil types, Y, Zr, Hf, Ta, Nb, Rb, and Sr of the phyllite and Th, U, Ba and Cs of the shale for the Perilla frutescens as well as Y, Zr, Hf, Rb, Sr, Ba and Cs of the phyllite and Ta, Nb, Th and U of the shale for the Sesamum indicum are chemically similar to the soils. In the comparisons of the each parts for the plant types, differences with the soils are big in the granite.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.3
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• pp.175-185
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• 2020

Three-dimensional registration is a process of matching data with or without a coordinate system to a reference coordinate system, which is used in various fields such as the absolute orientation of photogrammetry and data combining for producing precise road maps. Three-dimensional registration is divided into a method using points and a method using linear features. In the case of using points, it is difficult to find the same conjugate point when having different spatial resolutions. On the other hand, the use of linear feature has the advantage that the three-dimensional registration is possible by using not only the case where the spatial resolution is different but also the conjugate linear feature that is not the same starting point and ending point in point cloud type data. In this study, we proposed a method to determine the scale and the three-dimensional translation after determining the three-dimensional rotation angle between two data using quaternion to perform three-dimensional registration using linear features. For the verification of the proposed method, three-dimensional registration was performed using the linear features constructed an indoor and the linear features acquired through the terrestrial mobile mapping system in an outdoor environment. The experimental results showed that the mean square root error was 0.001054m and 0.000936m, respectively, when the scale was fixed and if not fixed, using indoor data. The results of the three-dimensional transformation in the 500m section using outdoor data showed that the mean square root error was 0.09412m when the six linear features were used, and the accuracy for producing precision maps was satisfied. In addition, in the experiment where the number of linear features was changed, it was found that nine linear features were sufficient for high-precision 3D transformation through almost no change in the root mean square error even when nine linear features or more linear features were used.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.21-28
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• 2009

Detailed information on soil characteristics is of great importance for the use and conservation of soil resources that are essential for human welfare and ecosystem sustainability. This paper introduces soil inventory of Korea focusing on national soil database establishment, information systems, use, and future direction for natural resources management. Different scales of soil maps surveyed and soil test data collected by RDA (Rural Development Administration) were computerized to construct digital soil maps and database. Soil chemical properties and heavy metal concentrations in agricultural soils including vulnerable agricultural soils were investigated regularly at fixed sampling points. Internet-based information systems for soil and agro-environmental resources were developed based on 'National Soil Survey Projects' for managing soil resources and for providing soil information to the public, and 'Agroenvironmental Change Monitoring Project' to monitor spatial and temporal changes of agricultural environment will be opened soon. Soils data has a great potential of further application in estimation of soil carbon storage, water capacity, and soil loss. Digital mapping of soil and environment using state-of-the-art and emerging technologies with a pedometrics concept will lead to future direction.

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.4
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• pp.109-121
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• 2003

The point of this research is the use of the high resolution satellite image for local government's new address system, as well as spatially field investigation support and base map error finding. Most local governments use scale 1/1,000 and 1/5,000 digital map for base map and field investigation. But field investigator's knowledge insufficiency and the lack of base map's currency make things too difficult from the beginning of the project. As the way of solving this problem, this research offers the use of the high resolution satellite image in new address system with cadence data of digital base map. Until now satellite image is not suitable for our situation because it has low resolution. But this problem was solved for 1m space resolution satellite image and it is being applied wider and wider. Now vector data and Raster data are integrated for complimenting of each weak point. In this study the use of the high resolution satellite image in new address system is expected to improve the quality of the results and reduce the expenses. In addition the satellite image can use local government's fundamental data.

• Journal of Korea Spatial Information System Society
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• v.3 no.2 s.6
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• pp.5-19
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• 2001

We are able to construct and utilize DEM(Digital Elevation Model) throughout the NGIS(National Geographic Information System) project. It is important that interpolation methods and appreciate size of grid for the construction of accurate DEM(Digital Elevation Model). There were several references related to the DEM(Digital Elevation Model) construction method, however they couldn't consider various topographical characteristics in the korea. In this study, we recommended that suitable interpolation method for each topographic element. After dividing Poonggi area into mountain, hill, urban, agricultural land, we constructed DEM(Digital Elevation Model) with various interpolation methods and grid size using 1:5,000 digital map. Then evaluated accuracy using elevation data which extracted from air-photo. The interpolation methods were analyzed and compared for various topographical conditions. As a result, Kriging method was superior to TIN method for all the topographical conditions. Another experiment was performed to examine optimal grid space for DEM with each topographical condition. 10m grid space was most suitable for mountain area and hilly districts, while 30m grid space was most suitable for urban area and farm land.

• Journal of the Korea Computer Graphics Society
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• v.16 no.4
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• pp.25-33
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• 2010

With the popularization of digital photography, people are now capturing and storing far more photos than ever before. However, the enormous number of photos often discourages the users to identify desired photos. In this paper, we present a novel method for fast and intuitive browsing through large collections of geo-referenced photographs. Given a set of photos, we construct a hierarchical structure of clusters such that each cluster includes a set of spatially adjacent photos and its sub-clusters divide the photo set disjointly. For each cluster, we pre-compute its convex hull and the corresponding polygon area. At run-time, this pre-computed data allows us to efficiently visualize only a fraction of the clusters that are inside the current view and have easily recognizable sizes with respect to the current zoom level. Each cluster is displayed as a single polygon representing its convex hull instead of every photo location included in the cluster. The users can quickly transfer from clusters to clusters by simply selecting any interesting clusters. Our system automatically pans and zooms the view until the currently selected cluster fits precisely into the view with a moderate size. Our user study demonstrates that these new visualization and interaction techniques can significantly improve the capability of navigating over large collections of geo-referenced photos.

• Journal of Cadastre & Land InformatiX
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• v.50 no.1
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• pp.5-23
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• 2020

According to the Korean Statistical Information Service(2019), the number of public land in Korea is 10,734,439parcels and 33,395㎢, accounting for 33.2% of the land area. In the meantime, the central government and local governments have been promoting the efficiency of public land management through annexation, but if the scale of cadastral record is different or the public land is registered in different types of cadastral maps, it is impossible to annexation and it is a major obstacle to the efficiency of public land management. As a way to solve these problems, the annexation method accompanied by survey was presented and the effect was analyzed. As a result, the number of parcels to be managed decreased by 91.7% and 99.6% of the actual survey cost was reduced despite the expenditure of only 54.9% of the existing method. It was found that the annexation survey of the public land, which are clustered by connection, can ultimately contribute to the efficiency of the public land management by newly establishing the indication of the public land. In the future, we hope that follow-up research on the public land management based on cadastral surveys will be conducted in various and in-depth ways.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.1
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• pp.52-61
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• 2004

Korea Water Resources Corporation carried out LiDAR survey to construct detailed terrain data for flood mapping and it is expected that much money is required in flood mapping of all over the country. Therefore, it is desirable to use NGIS digital map to construct preliminary modelling data for selection of flood mapping area. And the analysis of DEM error with respect to scale of digital map is necessary for the sake of applying digital map as the input data of flood mapping. We compared DEM from digital map with DEM from LiDAR survey. Especially we analyzed DEM error characteristics that is occurred with respect to the interpolation method that is used to construct DEM from TIN of digital map. As a result of analysis, digital map(1:1,000) showed smaller error than digital map(1:5,000) and DEM applying linear interpolation showed smaller error than DEM applying quintic interpolation. Especially, variation of DEM error by cell resolution was evaluated as very slight because urban district was composed of gentle slope.