• Journal of the Korean Association of Geographic Information Studies
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• v.3 no.1
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• pp.35-43
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• 2000

The slope gradient of the Korean Peninsula was analyzed by using DEM(DTED level 1). The Peninsula has high percentages of gentle slopes. But low plains and very steep slope regions are scarcely distributed in the Peninsula. Altitude lower than 150m areas are composed of plains and undulated plains. The steepest and most rugged topographies are observed in the range of altitude from 500m to 1,000m areas. The areas of altitude greater than 1,000m show plateau landscapes. By overlapping digital geology maps and the gradient grade maps, We revealed the characteristics of slope regions by geological districts. High latitude with steep slope are well developed in the geological districts of granitic gneiss(ARgr) and gneiss($PR_1$) of the Pre-Cambrian, sandstone of the Paleozoic era(P-T), and sedimentary rocks of the Mesozoic era($J_2$). Low altitude with gentle slope areas are representative in the districts of granite of the Mesozoic era($Jgr_1$), the Cretaceous sedimentary rocks of the Mesozoic era($K_1$, $K_2$) and the Cenozoic strata(N). Basalt extruded the Quaternary($Q_1$) are observed in the areas of very gentle slope but greater than 1,000m altitude.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.3
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• pp.91-101
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• 2010

As global warming has caused the number of abnormal changes in climate to increase throughout the world, much damage has occurred recently in Korean Peninsula which results from unexpected heavy rains, landslides, and floods from typhoons. To prevent and cope with these annually repeated natural hazards, the overall improvements are needed, including systematic management of the existing natural hazard information and improvement of hazard information. In this study, multi-purpose hazard information map based on digital image was constructed as an effective way to enhance hazard management considering regional characteristics and hazard response capabilities in the field. Multi-purpose hazard information map with a new concept by fusion of geospatial information and hazard attribute information is able to support quick decision for hazard management making and development of hazard information system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.2
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• pp.141-151
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• 1995

In generating DTM as basic data to GIS, the use of existing map is difficult to aquire current data and the method using airphotos needs cost for stereoplotting and ground control surveying. So, the method of DTM generation by satellite imagery is promising because satellite is able to observe wide area at once. In this study the program for SPOT bundle adjustment and image matching based on Coarse to Fine method is developed and various image enhancement algorithm is used for more accurate DTM generation and also evaluation of accuracy was carried out. Further more, orthophoto, a bird's eye-view, contour map producing, net-work analysis and terrain analysis were performed for GIS applications using generated DTM in this study. Generated DTM using SPOT stereo imagery is useful for GIS applications such as automated mapping, facility management, national geographic information system. Moreover developed automatic DTM generation pro-gram is studied, tested and verified more to be applicable to all the area.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.6
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• pp.641-650
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• 2011

Airborne LIDAR system, utilized in various forest studies, provides efficiently spatial information about vertical structures of forest areas. The tree height is one of the most essential measurements to derive forest information such as biomass, which can be estimated from the forest terrain model. As the terrain model is generated by the interpolation of ground points extracted from LIDAR data, filtering methods with high reliability to classify reliably the ground points are required. In this paper, we applied three representative filtering methods to forest LIDAR data with diverse characteristics, measured the errors and performance of these methods, and analyzed the causes of the errors. Based on their complementary characteristics derived from the analysis results, we have attempted to combine the results and checked the performance improvement. In most test areas, the convergence method showed the satisfactory results, where the filtering performance were improved more than 10% in maximum. Also, we have generated DTM using the classified ground points and compared with the verification data. The DTM retains about 17cm RMSE, which can be sufficiently utilized for the derivation of forest information.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.3
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• pp.401-408
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• 2009

A study for 3D-reconstruction and providing the geospatial information is in progress to many fields recently. For efficient providing the geospatial information, the present information has to be updated and be revised and then the latest geospatial information needs to be acquired economically. Especially, LiDAR system utilized in many study has a advantage to collect the 3D spacial data easily and densely that is possible to supply to the geospatial information. The 3D data of LiDAR is very suitable as a data for presenting 3D space, but in case of using the data without converting, the high performance processor is needed for presenting 2D forms from point data composed by 3D data. In comparison, basically the raster data structure of 2D form is more efficient than vector structure in cheap devices because of a simple structure and process speed. The purpose of this study, in case of supplying LiDAR data as 3D data, present the method that reconstructs to 2D raster data and convert to compression data applied by th tree construction in detail.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.16 no.2
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• pp.281-289
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• 1998

Korea is developing a Korea Multi-Purpose Satellite I (KOMPSAT-1) as one of Korea National Space Program, which will be launched in 1999. The EOC (Electro-Optical Camera) is the primary payload for KOMP-SAT-1. The main mission of EOC is to provide the images for the production of scale maps of Korean territory. This research is focused on methodology and possibility for the production of topographic maps using EOC sensor. Since the imagery from EOC is not yet available, SPOT Level 1A image data which are quite similar to those of EOC, and Intergraph Imagestation (Digital Photogrammetric Workstation) are implemented in the process of sample digital map generation. The sample digital maps generated from SPOT stereoimages were compared and analyzed with the existing 1:50,000 scale digital map produced by National Geography Institute. The feasibility and problem encountered in 1:50,000 scale digital mapping using SPOT stereoimages were presented. Based on results, the feasibility and further research areas for KOMPSAT-EOC in the line of 1:25,000 and 1;50,000 digital mapping were discussed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.2
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• pp.137-145
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• 2003

Currently, the availability of 3-D topographical survey by combination of GPS and Echo Sounder has been increased in the various field like as the construction of structure, the dredging and the reclamation in the ocean and river, and observation of topographic change in seabed or riverbed. In this case, the error of depth sounding can divide in form that is happened by combination of GPS and Echo Sounder, and form that is happened in Echo Sounder itself, In this study, in the case happen by Echo Sounder itself, analyzed error by specially about geological features of the seabed and riverbed that is specular surface of sound wave and wished to present solution way. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter and residual error and we defined correction formula, Y=-0.00474$^{*}$In(X) -0.0045 by the regression analysis. and then we verified applicability of correction formula. As the result, if measure Preliminary investigation or pre-survey the geological features for the survey area at topographical survey of estuary riverbed, we presented the error correction formula that estimate and can correct of error by Echo Sounderer.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.1
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• pp.21-32
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• 2016

Open-pit mines are the critical infrastructure for acquiring natural resources. Since it could be endangered by environmental and safety problems during operations, continuous monitoring is required for this type of mine. However, the domestic level management and accumulation of present state data of the topographical alteration are incurred by the development and restoration of open-pit mines relying on digital topographic maps and site surveys. Because of it, other than an expert cannot be viewed easily examines those changes information of open-pit mines in the domestic level. If the efficient management and public access of the open-pit mine is targeted, it is easy to build a web-based three-dimensional monitoring system, utilized in the space information software of open source. Therefore, we purposed on developing an open-pit mine monitoring system to support the development and restoration of the ecology-friendly environment, which could be easily monitored by the general public for those changes within terrain and environments due to operations of the mine.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.12 no.1
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• pp.53-59
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• 1994

The purpose of this paper is to use geo-spatial information system for effective operation and management of the underground facilities. The subject area is selected and collected all of the drawing in order to get the coordinate points(tic), which become the standard of the subject area and that can be gotten by way of practising control surveying from a existing triangulation station spatial information and attribute information are classificated from obtained data. Also, after giving the code in the attribute information to make it data-based, connecting spatial information with the attribute information to overlap layer each other, and compared the positional accuracy of the data. From the results of this study, conclusions are acquired as follows; 1) To construct the Database of the spatial and attribute data, which contain all kinds of drawings in underground structures, the reservation of registers and the details of changes and so on, results in easily referencing, compiling and analyzing the reserved data in system as their own purposes. 2) It is expected that we can effectively operate and manage the situation among the underground facilities so accurately that we may obviate the safety accidents or the damages of life and property.

• Korean journal of communication and information
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• v.66
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• pp.5-27
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• 2014

The past, present, and future of online journalism in Korea are inextricably bound up with the portal site news services. In traditional journalism, finite news media took hold on news consumption completely because of performing news production and distribution simultaneously. Since then, in the age of multi-media and multi-channel, the audience selection has become more important because of greatly increasing news media and then exploding news production. In online journalism, the news distribution have emerged as the most important field because of the intensive consuming the portal site news services making use of various news easier, the characteristic of news consumption focusing on not news media brands but news media contents, etc. Therefore, the news present landscape of Korean journalism oriented news distribution has been completed by that the portal site news services became the symbol of online journalism. That the portal site news services performing only news distribution have more influence than the paper based online newspapers and Internet based online newspapers producing news means the change of media power. By this, a conflict between news media and portal site news services appears at all times.