• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.1
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• pp.24-31
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• 2001

Most of the natural calamities occurred in South Korea are due to rainfall, which are occurred during rainy season, June to September. The life-calamity reported in those seasons were over 75%, and the dead rate by the rainfall was about 98%. Especially, the disasters occurred in Pusan and Kyongsang-Namdo were highest of the whole country. The capability of landslide in this area was very high, which is included to Class 3 or Class 4 of disastrous risk grade suggested by the GIS system(Lee Su-Gon,1999). Those are based on the characteristics of topographical and meteorological data. In this study, the rainfall characteristics in Pusan were analyzed through the relationship between the cumulative rainfall and the maximum hourly rainfall. The landslide in this area depends on the elapsed time after maximum hourly rainfall intensity, and the most of landslide in Pusan recorded during within 3 hours after pick-time of rainfall intensity.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.3
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• pp.217-223
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• 1984

An attempt is made to predict the wear behavior of ion-nitrided metal, when wear arises from asperity interactions. The analysis demonstrates that wear mechanisms are not inconsistent with observed behavior, indicates and approaches to a better appreciation of the effects of such factors as nitrided layer formation and surface topographical features. It was found on ion-nitriding that penetration rate and case development are faster and wear properties of the final product are more improved than conventional gas and salt-bath methods of nitriding.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.201-206
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• 2008

방위, 경사, 고도 와 같은 지형인자는 생태현상에 영향을 미치는 대표적인 환경인자로, 생태현상을 파악 및 예측하기 위해서는 이들 지형인자의 분석이 필요하다. 또한 지형인자 분석에 앞서 이용자료의 격자크기를 결정해야한다. 본 연구는 소나무의 공간분포와 출현패턴을 생태학적으로 잘 설명하기 위한 DEM의 최적 격자크기를 제안하고, 궁극적으로는 생태적으로 중요한 최적의 공간구획방법을 찾고자하였다. 그 결과, 200m의 격자크기를 갖는 DEM은 주능선에 의해 방위를 동, 서, 남으로만 구분한 반면, 1m 격자크기의 DEM은 작은 부능선들에 의해 방위를 동, 서, 남, 북으로 구분하였다. 일정규모 이하의 격자크기에서 소나무는 모든 방위에 나타났지만, 격자크기가 증가함에 따라 북쪽과 남쪽 사면에서의 출현빈도는 점차 감소하였다. 또한, 200m 격자크기에서의 빈도분석은 육안분석에서처럼 소나무가 주로 서쪽과 동쪽 사면에 출현한다는 것을 보였다. 능선으로부터의 거리에 따른 소나무 출현빈도는 60m이상의 거리를 두고 분석하였을 때, 육안분석과 같이 소나무가 능선주변에 주로 분포하는 것으로 나타났다.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.240-246
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• 1999

The determination of surface topography is believed to be extremely important in the areas of contact mechanics, adhesion and friction. In order to describe topography of various frictional surface, the wear test was carried out under different experimental conditions in dry friction. And fractal descriptors was applied to frictional surface of laser modified steel with image processing system. These descriptors to analyze surface structure are fractal dimension. Surface fractal dimension can be determined by sum of intensity difference of surface pixel. Topography of frictional surface can be effectively obtained by fractal dimensions.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.11a
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• pp.381-384
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• 2004

The goal of this study is to generate a landslide susceptibility map using GIS(geographic information system) based method. A simple and efficient algorithm is proposed to generate a landslide susceptibility map from DEM(digital elevation model) and existing maps. The categories of controlling factors for landslides, aspect of slope, soil, topographical index, landuse, vegetation are defined, because those factors are said to have relevance to landslide and are easy to obtain theirs sources. The weight value for landslide susceptibility is calculated from the density of the area of landslide blocks in each class. Finally, a map of susceptibility zones is produced using the weight value of all controlling factors, and then each susceptibility zone is evaluated by comparing with the distribution of each controlling factor class.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.03a
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• pp.205-218
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• 2002

Recently, the water pollution of coastal sea area including harbor, bay and inland sea has been very serious and it causes various environmental impacts. In this study, water flow system of Danghang Bay, which has the narrow and long topographical characteristics with the narrow bay mouth and its flow is influenced principally by the tidal current, is investigated experimentally and numerically. In order to understand the tidal system of Danghang Bay, harmonic analysis is performed based on measured tidal range and flow velocity In addition, numerical model for tidal exchange is developed considering conditions of Danghang Ray. Calculated results show good agreement with measurements. Lastly. based on the proposed numerical model, exchange ratio of seawater volume in Danghang Bay is predicted.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.326-330
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• 2003

The purpose of this study was to develop railroad geotechnical management system using Web GIS and the DB used in system included railroad informations and digital maps. Digital maps are primarily based on a topographical map(NGIS, 1:5000) and by adding digital maps(KRRI, 1:5000) and their spatial database system to NGI code layer, the management system was developed. The system was connected to geotechnical database already developed. The system was able to separate three parts which were layer choice, geotechnical information view and geotechnical analysis and it was possible to save geotechnical and spatial informations using ZEUS DB simultaneously. ZEUS/X was used for usefulness of GIS operation and by offering GUI, user interface for facility was achieved. Geotechnical and spatial informations in this system will provide basic data for plans, design and construction of railway lines in practical use.

• Journal of Industrial Technology
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• v.30 no.A
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• pp.95-101
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• 2010

This paper is results of case study on characteristics of debris flow occurred at Jecheon during a heavy rainfall in 2009. The site studied is the mountain area located at Palsong-ri Bongyang-op in Jecheon-si where serious damages due to debris flow were occurred by heavy rainfall during July 7 to July 16 in 2009. Intensity and duration of rainfall causing debris flow were analyzed on the basis of AWS data. Characteristics of debris flow such as initiation, transportation and deposition were investigated through field reconnaissance. The geological and topographical characteristics of slope where debris flow was triggered were figured out and characteristics of erosion on the bottom and sides of valley during transportation of debris flow were also investigated. The slope and boundary of valley where the debris flow started to be deposited were studied.

• Macromolecular Research
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• v.11 no.5
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• pp.387-392
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• 2003

The ablation effects of Ar-plasma treatment and alkali-decomposition behavior in NaOH solution of polyethylene terephthalate (PET) film were investigated. The modifications were evaluated by analysis of atomic force microscopy topographical changes, and by the measurement of decomposition yield in conjunction with heats of formation and electron densities of acyl carbon calculated by Parameterization Method 3 method. It has shown that the alkali-decomposition is hampered by plasma treatment and its decomposition yield is closely related with plasma treatment conditions such as exposure time to plasma. Plasma-treated PET films exhibited lower decomposition yield, compared to that of virgin PET. Increasing plasma exposure time contributes positively to decrease the decomposition yield. It has also shown that the topography of PET surface was affected by the base-promoted hydrolysis as well as Ar-plasma treatments. These behaviors are attributed to the decreased nucleophilicity of acyl carbon damaged by the ablation of Ar-plasma.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1178-1183
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• 2006

This paper describes the plans of considering the environmental influences in the preliminary feasibility investigation of railroad work. Because the cost-benefit analysis method about the environmental costs by air pollution and traffic noise is mainly applied in preliminary feasibility investigation, not only the verification in the calculation method of these environmental costs but also the consideration in the environmental costs of the topographical damage and the ecosystem extinction by railroad work is needed. The environment-friendly plans in choosing the locations of the railroad route and station are also suggested, and they include (1) consideration of environment protection area, residential zone, and region with scenic beauty, (2) application of the existing railroad route and station, and (3) railroad route parallel to another traffic facility.