• Journal of Korean Society of Forest Science
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• v.18 no.1
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• pp.13-16
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• 1973

The article was carried out to study the relationships between the causes of barelands and topographic factors such as altitudes, slopes and bearings. Using the forest utility demarcation maps of 1 : 50,000 in scale and the aerial photographs drawn and taken by the Forest Resources Institute, Seoul, the areas of each bareland and the topographic factors were calculated from the maps and photographs and the critical causes of barelands were analyzed based on the various topographic factors. The results obtained were as follows: 1. There were some positive relation between area of barelands and slopes, and between area of barelands and altitudes. 2. However. there were no significant difference between number of barelands and altitudes, between number of barelands and slopes, between number of barelands and bearings, and between area of barelands and bearings.

• Journal of the Korean earth science society
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• v.24 no.4
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• pp.325-336
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• 2003

The onset time of sea breeze at Haeundae is faster than that at Suyoung in spite of the observation site at Suyoung being 5m and that of Haeundae being 1 km away from the coastline. We therefore simulate the effects of terrain on the onset time of sea breeze at Suyoung and Haeundae districts by using the LCM(Local Circulation Model). This phenomenon is due to the nighttime density flow, which is created by nighttime radiative cooling. It follows the slope of the highlands surrounding the urban area, gathers at a central area of Busan, and then flows out to a lower area like Suyoung river. This process continues after sunrise. In researching the AWS wind speed, we find an important thing. That is to say, the nighttime mean wind speed at Suyoung is three times greater than that at Haeundae. This property shows that Suyoung is an outflow channel of nighttime air mass. The above observed data shows that terrain effect has a important role on the onset of sea breeze.

• Journal of the Korean Geographical Society
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• v.40 no.3 s.108
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• pp.335-352
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• 2005

The question of whether fan type surface developed at the foot of mountains is pediment or alluvial fan has been discussed consistently through the Korean geomorphic history. Unfortunately the term, 'alluvial fan' was scarcely used, also even the existence of alluvial fan has been denied throughly for a long time in Korea. The negation of alluvial fan brought some difficulties in the development of the related Geomorphology. In order to resolve such a problem, more logical and exquisite theory by examination of geomorphic process must be systematically presented on the basis of overall problem recognition. The objective of this study is to represent the theoretical indicator based on the investigation of the points at issue that the existence of alluvial fan in Korea was denied. Moreover, we selected 13 alluvial fans in southern part of Korean Peninsula to compare with the worldwide alluvial fans according to theoretical indicator, and analysed their geomorphic distributional characteristics.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.555-561
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• 2006

This study was carried out to investigate the suitable place for growth by analyzing the ecological environment of multi-use tree species to be spontaneous in Chungbuk Province, and derive the suitable place for forestation. At the test of the independence of multi-use tree species, as the significant correlation of the other tree species except Quercus acutissima - Zanthoxylum schinifolium was different by the survey location, it is concluded that the share relation of the ecological niche among tree species is largely influenced not only by the affinity of tree species but the growth environment. As the result of the correlation analysis between environment factors and tree clusters, it was analyzed that tree clusters were much influenced by the topography and the altitude among the variable environment factors; the topography, altitude, the direction of hillside, the slope and the number of tree species appearing. It was investigated that the cluster of Acer mono - Betula costata was distributed to the valley from low hillside to have high altitude, and the clusters of Kalopanax pictus - Ulmus davidiana var. japonica and Fraxinus rhynchophylla - Rhus trichocarpa were sporadically distributed to broad location because their geographical adaptation powers are high.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.4
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• pp.365-371
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• 2003

Digital high resolution cameras are widely available, and are increasingly use in digital close-range photogrammetry. And photogrammetry instruments are developing rapidly and the precision is improving continuously. The building of 3D terrains of high precision are possible and the calculation of the areas or the earthwork volumes have high precision due to the development of the techlique of the spatial information system using computer. Using the digital camera which has capacity of keeping numerical value by itself and easy carrying, we analyze the positioning error according to various change of photographing condition. Also we try to find a effective method of acquiring basis data for 3D monitoring of high-accuracy in pixel degree through digital close-range photogrammetry with bundle adjustment for local terrain model generation and 3D embodiment of tumulus. In the study is about to efficient analysis of digital information data fer conservation of cultural properties.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.2
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• pp.121-127
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• 2000

Kinematic GPS surveying which can obtain much 3D topographical information through short-time measurement is being utilized mainly in the short baseline less than a few kilometers. Because the decision of position for the long baseline depends on the static GPS surveying which needs long time measurement, the method for measuring the position of long baseline is needed. In this study, the accuracy of the baseline according to the baseline distance, ephemeris, and observation time by GPS surveying is analysed to confirm the application of kinematic GPS surveying for the long baseline. As the result of this, the acquisition of 3D topographical information by GPS surveying in a few minutes will be possible when PDOP is less than 4, and the fast precise ephemeris is used within 60 km. Also, the accuracy is similar to that of final precise ephemeris of IGS. If a lot of studies about the long baseline kinematic GPS surveying are processed, the acquisition of topographical information for various industry including land development will be obtained more efficiently.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.6
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• pp.591-598
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• 2008

Recently, the government has improvement projects of dangerous road for the site that has very high accident rate due to bad geometric structures of the road. Although, route selecting of the road is a basic and important process, but the process of route selecting must consider the technical, safety and environment factor together. Also, the technology for the 3-dimensional terrain model can be used as an important factor in planning and designing for selecting alternative route projects. In the course of experimenting with the 3-dimensional topography generated by the combination of the digital map and drawing of route, the technology as been developed to offer the multi-dimensional access to the potential construction sites from the nearby main roads. This 3-dimensional digital elevation model has made it possible to make various terrain analysis base on GIS, which provides real-time virtual access to the designated construction sites for development planning and construction projects. Therefore, this study presents a reasonable plan for route selecting from some alternative routes through subjective evaluation and classify the methods linked basic design of road construction.

• Journal of the Korean association of regional geographers
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• v.8 no.1
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• pp.98-109
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• 2002

The long term land-cover changes and the pattern of morphological changes in foredune ridges and unvegetated dunes were investigated for about 30 years through analysing aerial photographs in Shinduri coastal dunefield, Korea. As a result, forested dune area increased while unvegetated dune area decreased continuously since 1967. Foredune ridges retreated landward about 80m away from the former coast-line in the middle part while they advanced seaward after construction of dike in the northern part during last 3 decades. Unvegetated dunes in the middle part of the dunefield were eroded at seaward side and moved landward away. These facts mean not only coastal dune area has been affected by man-made effects such as afforestation and coastal developments but also shinduri coastal dune area has been stabilized by plants and has been negative sediment budget.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.1
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• pp.12-22
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• 2016

Lidar-based hazard avoidance landing system for lunar lander calculates hazard cost with respect to the desired local landing area in order to identify hazard and designate safe landing point where the cost is minimum basically using slope and roughness of the landing area. In this case, if the parameters are only considered, chosen landing target can be designated near hazard threatening the lander. In order to solve this problem and select optimal safe landing point, hazard cost based on relative distance to hazard should not be considered as well as cost based on terrain parameters. In this paper, the effect of hazard cost based on relative distance to hazard on safe landing performance was analyzed and it was confirmed that landing site designation with two relative distances to hazard results in the best safe landing performance by an experiment using three-dimensional depth camera.

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.5
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• pp.553-563
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• 1999

The Spatial Database Engine(SDETM) developed by Environmental Systems Research Institute, Inc. is a spatial database that employs a client-server architecture incorporated with a set of software services to perform efficient spatial operations and to manage large, shared and geographic data sets. It currently supports a wide variety of spatial search methods and spatial relationships determined dynamically. Spatial objects in the space world can be changed by either non-spatial operations or spatial operations. Conventional geographical information systems(GISs) did not manage their historical information, however, because they handle the snapshot images of spatial objects in the world. In this paper we propose a spatio-temporal data model and an algorithm for temporal relationship macro which is able to manage and retrieve the historical information of spatial objects. The proposed spatio-temporal data model and its operations can be used as a software tool for history management of time-varying objects in database without any change.