• Water for future
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• v.15 no.3
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• pp.49-55
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• 1982

The purpose of this study is to examine the methods of estimation, comparing U.S. SCS method and $\Phi$-index with effective rainfall. And also comparision was made among SCS method, Chow method and Mockus method as to the peak discharge of design storm hydrograph by small river basin. Hydrological data of the Shin river basin which was used in this study and the results of study are as follow; 1) As a result of applying the SCS method to determine the effective rainfall out of total rainfall, it turned out that the everage CN of the basin as obtained by the analysis of hydrologic soil-cover complex was varied as follows; AMC-I was 27.9%, AMC-II 16.4%, AMC-III 8.1% less than the value given by SC method using discharge measurement. 2) The comparision of effective rainfall by the ungaged SCS method with that of gauged $\Phi$-index method showed that the $\Phi$-index method showed that the $\Phi$-index method gives large value by 4.7% to those given by hydrograph. The result of analysis by the SCS method resulted in great difference from discharge measurement. 3) The comparision of SCS method, Chow method, and Mockus method showed that dimensionless hydrograph of SCS method and Chow method were close to the peak discharge of the gauged unit hydrograph, while the other methods gave far different results. 4) Attempts were made, for a better adaptation to the Shin river basin, to introduce lag time formula constant of dimensionless hydrograph of the SCS method by using the peak discharge of the gauged flow hydrograph.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.4
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• pp.77-85
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• 1990

The application of remote sensing in small scale mapping has recently been widened to various fields such as information analysis of landuse, environmental conservation and natural resources. SPOT imagery, in particular, offers data which can be processed for 3-dimensional point determination. This is made possible by its high resolution, appropriate swatch width/altitude ratio and stereo imaging capabilities. This study aims to develop a suitable polymonial and an algorithm in the determination of exterior orientation which is essential in the 3-dimensional point determination of SPOT imgery. An algorithm is presented in this study to determine the exterior orientation of a preprocessed level lB film of the satellite image. It was found that a polynominal of 15 parameters is the best fit polynominal for exterior orientation determination, where 1st order line function is used for positon ($X_o$, $Y_o$, $Z_o$) and 2nd order line function is used for orientation (${\kappa}_o$, ${\phi}_o$, ${\omega}_o$).

• Journal of the Korean Association of Geographic Information Studies
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• v.6 no.1
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• pp.119-131
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• 2003

Rainfall-runoff process is under the control of hydrologic parameters having temporal and spatial variety. Accordingly, it is difficult to efficiently deal them since many parameters and various information are required to perform hydrologic simulation. So the purposes of this study is to estimate the runoff volume by frequency using GIS techniques and NRCS method. The analysis of frequency rainfall is analyzed using FARD 2002 program and the result of goodness of fit test show that Log-pearson type III is suitable distribute type for the applied area. TOPAZ program used for the analysis of DEM data examining into geological characteristic. NRCS curve numbers estimated using landuse map and soil map for the estimation of effective rain fall in the basin. The storm Type II and Type III were used as the type for the application of NRCS. The result of application show that the runoff volumes above 80 years frequency in return period have similar patterns regardless of Type II and Type III. In addition, the results of comparison with runoff volumes by frequency in the report of river improvement master plan show that it have similar volumes as the relative errors for them of 80, 100 years frequency are each 7.65%, 5.33%.

• Journal of the Korean GEO-environmental Society
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• v.19 no.4
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• pp.27-32
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• 2018

There were many ground excavation projects from past to present to make effective use of the limited land. And it is very important to predict the ground behavior depending on construction stage for ground excavation. Excavation of the ground involves changes in the stress and displacement of the ground around the excavated surface. Thus it affects the stability of the adjacent structure as well as the excavated surface. Therefore, it is very important to predict the ground behavior and stability of adjacent structure. And nowadays, numerical analysis methods are most often used to predict the effects of ground excavation. Recent, improvements of numerical analysis programs, along with improved computer performance, have helped solve complicated ground problems. However, except some specialized numerical analysis, most numerical analysis often predicts larger excavation floor displacement than field data due to adopt the Mohr-Coulomb analysis model. As a result, it raise the problem that increasing the amount of support on ground and structure. In this study, ground behavior analysis depending on analysis model (Mohr-Coulomb, Duncan-Chang, Modified Mohr-Coulomb and Hardening Soil model) has been carried out through the numerical analysis. When numerical analysis is carried out, this study is expected to be used as a basic data for adopting a suitable analysis model in various ground excavation project.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.139-153
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• 2014

This study contemplates the utopian landscape recognized by the scholars with twenty three pieces of 'travel record'. Consequently, five key words - Mureungdowon(武陵桃源), Byeolcheonji(別天地), Dongcheon(洞天), Chonghakdong, Eungeoji(hermitage) - are chosen for comprehending the utopia and their landscape characteristics are organised as follows. Mureungdowon in Jirisan Mountain which the scholars dreamed of is a flatland with the full energy for local vegetation and domestic animals in the mysterious and deep gorge. This utopia eventually reflects the rural landscape. Byeolcheonji is a utopia combining the concept of a fairyland and beautiful scenery. The scholars also used the term 'Dongcheon' for naming the enclosed landform which is suitable for seclusion and defining the some areas of beautiful scenery. Cheonghakdong, which is set only in Jirisan Mountain, has been formed by the stone scenery of gorges and Buril waterfalls around the whole area of Burilam Hermitage, the vegetation scenery of pine trees and bamboos with the legend of Choi Chiwon and his engraved inscription on a rock. Adding to the utopia passed down, the scholars perceived the village with geographical features with back to the mountain and facing the water, the river practising the trade, the flatland enclosed by bamboo forests, the vegetation mainly consisting of fruit trees and beautiful scenery as the utopia realized on earth. It is equivalent to the world of human beings laboring appropriately and living in Mother Nature. As mentioned above, this study has significance for apprehending the relevance between the culture of strolling in the mountains by the scholars of Joseon Dynasty and the fairyland and explaining the various traditional utopias from the inherited concepts from China to the naturalized realistic utopia.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.4
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• pp.327-343
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• 2020

This study proposes a method to improve the geometric quality of KOMPSAT (Korea Multi-Purpose Satellite)-3/3A Level 1R imagery, particularly for efficient disaster damage analysis. The proposed method applies a novel grid-based SIFT (Scale Invariant Feature Transform) method to the Planetscope ortho-imagery, which solves the inherent limitations in acquiring appropriate optical satellite imagery over disaster areas, and the KOMPSAT-3/3A imagery to extract GCPs (Ground Control Points) required for the RPC (Rational Polynomial Coefficient) bias compensation. In order to validate its effectiveness, the proposed method was applied to the KOMPSAT-3 multispectral image of Gangnueng which includes the April 2019 wildfire, and the KOMPSAT-3A image of Daejeon, which was additionally selected in consideration of the diverse land cover types. The proposed method improved the geometric quality of KOMPSAT-3/3A images by reducing the positioning errors(RMSE: Root Mean Square Error) of the two images from 6.62 pixels to 1.25 pixels for KOMPSAT-3, and from 7.03 pixels to 1.66 pixels for KOMPSAT-3A. Through a visual comparison of the post-disaster KOMPSAT-3 ortho-image of Gangneung and the pre-disaster Planetscope ortho-image, the result showed appropriate geometric quality for wildfire damage analysis. This paper demonstrated the possibility of using Planetscope ortho-images as an alternative to obtain the GCPs for geometric calibration. Furthermore, the proposed method can be applied to various KOMPSAT-3/3A research studies where Planetscope ortho-images can be provided.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.5
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• pp.42-54
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• 2008

The objective of this study is to critically examine the result and the quality of urban park design as infrastructure by analyzing the landscape architectural design competition for Cheongna New City, which was organized by the Korea Land Corporation. This paper is meaningful in that it broadly examines several recent design competitions for urban parks, thereby discussing what the future urban park should be. This study explores the existing analysis methods of design competitions in order to establish a comprehensive method of analysis for the Cheongna competition. Through reinterpreting the concept of the urban park as infrastructure and the design strategies of landscape urbanism, nine key words and a framework for the analysis of urban park design are established. By analyzing the guidelines for the competition, five key words; networking, site, ecology, scale, and infrastructure have been selected and are used as the framework of analysis for the competition. The analysis of the contestants of the competition based on the proposed analysis method leads to a few implications for urban park design as infrastructure: networking and scale from the perspective of the development site; the creation of a sense of place and symbolism in creating the urban image; planning for an ecological urban environment; focus on the significance of the urban park as infrastructure. These implications are highlighted and discussed by the contestants through a variety of experiments. These ideas, however, are provided as a simple configuration of shapes and conceptual explanations and fail to be developed into synthetic, practical strategies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.125-134
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• 2017

Unusual precipitation caused by typhoons and severe rain stormscan threaten human life and property. Thus, various organizations prepare emergency action plans (EAPs) to provide proper guidelines for operators, experts, and emergency response personnel to protect and enhance critical infrastructure. For example, FEMA and DHS have various types of EAPs for dams, levees, and other structures to protect people and property. FEMA defines EAPs as official documents to decrease the damage and impact in emergency situations and to reduce casualties. These documents should consider all possible situations in an emergency and can reduce problems in facility management. This study analyzes EAPs for infrastructure from the USA, Japan, and Korea in order to suggest an ideal EAP framework. EAPcontent can include how to guide experts and operators in disaster stages (mitigation, preparedness, response, and recovery), how to operate emergency equipment, and how to protect critical infrastructure and life. The suggested EAP framework performed very well in a test location. It can therefore be used for infrastructure organizations in Korea and to inform of the appropriate processes and methods for risk reduction in flood disasters.

• Korean Journal of Remote Sensing
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• v.12 no.2
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• pp.169-198
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• 1996

The objectives of this investigation are : 1. To analyze spectral signature and the associated vegetation index for geometric illumination conditions inf1uenced by low solar elevation and high slope orientations in mountainous forest. 2. To assess the accuracy of the spectral angle mapper classification for the a winter land cover in comparison with the maximum likelihood classification. 3. To produce the image of water quality and water properties that could be used to estimate the water pollution sources and the tide-included by turbid water in estuarine and coastal areas. These objectives are to characterize environmental and ecological monitoring applications of the Nak-Dong River Basin by using Fuyo-1 OPS VNIR data acquired on December 26, 1992. The results of this paper are as follows : 1. The spectral digital numbers and vegetation indexes (NDVI and TVI) of mountainous forest are higher on the slope facing the sun than on the slope hidden the sun under low sun elevation condition. 2. The spectral angle mapper algorithm produces a more accurate land cover classification of areas with steep slope, various aspects and low solar elevation than the maximum likelihood classifier. 3. The maximum likelihood classification images can be used for identifying the location and movement of both freshwater and salt water, regardless of geometric illumination conditions. 4. The color-coded density sliced image of selected water bodies by using the near-infrared band 3 can provide distribution of the water quality of the Lower Nak-Dong River. 5. The color-coded normalized difference vegetation index image of the selected mountain forest is suitable to classify winter vegetation cover types, i.e., forest canopy densities for slope orientations.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.277-286
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• 2021

This study compares the long-term hydrological cycles of the Seolmacheon and Cheongmicheon basin by applying the structural equation model (SEM). These two basins are found different especially in their land-use pattern. Both basins have the actual evapotranspiration data measured by the eddy-covariance method as well as the rainfall and runoff data. The length of the data considered in this study is nine years from 2010 to 2018. The structure of the SEM is determined by considering the correlations among the data as well as the general knowledge on the hydrological cycle. As a result, a total of three SEMs are applied sequentially to analyze their fittings. As irony would have it, two basins are found to be similar in the application of one SEM, but different in the application of another. Especially, when considering the feedback process between precipitation and evapotranspiration, two basins are found to be very different. That is, the feedback process between precipitation and evapotranspiration is found to be significant in the Cheongmicheon basin where the portion of agricultural area (i.e., paddy) is more than 40%.