• Title/Summary/Keyword: Natural hazard

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Prediction of Landslide Using Artificial Neural Network Model (인공신경망모델을 이용한 산사태 예측)

  • 홍원표;김원영;송영석;임석규
    • Journal of the Korean Geotechnical Society
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    • v.20 no.8
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    • pp.67-75
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    • 2004
  • The landslide is one of the most significant natural disasters, which cause a lot of loss of human lives and properties. The landslides in natural slopes generally occur by complicated problems such as soil properties, topography, and geology. Artificial Neural Network (ANN) model is efficient computing technique that is widely used to solve complicated problems in many research fields. In this paper, the ANN model with application of error back propagation method was proposed for estimation of landslide hazard in natural slope. This model can evaluate the possibility of landslide hazard with two different approaches: one considering only soil properties; the other considering soil properties, topography, and geology. In order to evaluate reasonably the landslide hazard, the SlideEval (Ver, 1.0) program was developed using the ANN model. The evaluation of slope stability using the ANN model shows a high accuracy. Especially, the prediction of landslides using the ANN model gives more stable and accurate results in the case of considering such factors as soil, topographic and geological properties together. As a result of comparison with the statistical analysis(Korea Institute of Geosciences and Mineral Resources, 2003), the analysis using the ANN model is approximately equal to the statistical analysis. Therefore, the SlideEval (Ver. 1.0) program using ANN model can predict landslides hazard and estimate the slope stability.

Hazard Map of Road Slope Using a Logistic Regression Model and GIS (Logistic 회귀모형과 GIS기법을 활용한 접도사면 붕괴확률위험도 제작)

  • Kang Ho-Yun;Kwak Young-Joo;Kang In-Joon;Jang Yong-Gu
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.339-344
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    • 2006
  • Slope failures are happen to natural disastrous when they occur in mountainous areas adjoining highways in Korea. The accidents associated with slope failures have increased due to rapid urbanization of mountainous areas. Therefore, Regular maintenance is essential for all slope and conducted to maintain road safety as well as road function. In this study, we take priority of making a database of risk factor of the failure of a slope before assesment and analysis. The purpose of this paper is to recommend a standard of Slope Management Information Sheet(SMIS) like as Hazard Map. The next research, we suggest to pre-estimated model of a road slope using Logistic Regression Model.

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Researches Related to Seismic Hazard Mitigation in Taiwan

  • Loh, Chin-Hsiung;Yeh, Chin-Hsun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.2 no.3
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    • pp.13-26
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    • 1998
  • In view of the rapid development of economics and technology, perilous meteorological and geological conditions often cause natural disasters and result in severe loss of lives and properties in Taiwan. To promote multi-hazard mitigation strategies in an integrated a, pp.oach, the National Science Council established a National Science and Technology Program for Disaster Mitigation in January 1998. This program emphasizes on the implementation of research results in the National Disaster Management System. This paper describes the earthquake loss estimation methodology that is currently developed in Taiwan. Topics of potential earth science hazards (PESH) and building vulnerability analysis are described in detail.

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Hazard Prevention using Multi-Level Debris Flow Barriers (다단식(다단식) 토석류 방호책을 이용한 재해방지 시스템)

  • Lee, Sung-Uk;Choi, Seung-Il;Choi, Yu-Kyung
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.815-829
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    • 2008
  • Debris flows are a natural hazard which looks like a combination of flood, land and rock slide. Large rainfall in July 2006 produced several large scale debris flows and many small debris flows that resulted in loss of life and considerable property and railway damage, as was widely reported in the national media. The hazard "debris flow" is still insufficiently researched. Furthermore debris flows are very hard to predict. Flexible Ring net barriers are multi-functional mitigation devices commonly applied to rock fall or floating wood protection in floods, snow avalanches and also mud flows or granular debris flows, if properly dimensioned for the process or processes for which they are intended. Overtopping of the barriers by debris flows and sediment transport is possible, supporting the design concept that a series of barriers may be used to stop volumes of debris larger than are possible using only one barrier. The future for these barrier concepts looks promising because these barriers represent the state of art for such applications and are superior to many other available options.

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Removal of Arsenic from Leachate of Tailing using Laboratory-synthesized Zerovalent Iron

  • Kim, Soon-Oh;Jung, Young-Il;Cho, Hyen-Goo;Park, Won-Jeong;Kim, In-Seon
    • Journal of Applied Biological Chemistry
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    • v.50 no.1
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    • pp.6-12
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    • 2007
  • Feasibility of laboratory-synthesized zerovalent iron was investigated to remove arsenic from leachates of tailings taken from an Au-Ag abandoned mine. The tailings were seriously contaminated with arsenic, and its potential adverse effect on the ecosystems around the mine seems to be significantly high. Long-term column experiments were conducted for about 3.5 months to evaluate the effectiveness of the synthesized zerovalent iron for removal of arsenic. Over than 95% removal efficiency of As was observed in the zerovalent iron mediated tests. In addition, the XRD data suggest that the corrosion products of ZVI were identified magnetite, maghemite, goethite, and lepidocrocite, all of which support Fe(II) oxidation as an intermediate step in the zerovalent iron corrosion process. The results indicate that arsenic can be removed from the tailing-leachate by the mechanism of coprecipitation and/or adsorption onto those iron oxides formed from ZVI corrosion.

Integrity Assessment of Spread Footing Pier for Scour Using Natural Frequency (고유진동수를 이용한 확대기초 교각의 세굴 건전성 평가)

  • Park, Byung-Cheol;Oh, Keum-Ho;Park, Seung-Bum
    • Journal of the Korean Society of Hazard Mitigation
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    • v.5 no.2 s.17
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    • pp.29-35
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    • 2005
  • In Korea more than ninety bridges are collapsed every year by flood, which causes the scour of pier foundation. Researches on the quantitative assessment method to assess the integrity of bridge against scour have not been organized systematically in the bridge design practice and maintenance area. In this study, dynamic characteristics assessment experiments are carried out as an emergency inspection method to assess the integrity of the pier foundation for scour after a flood. According to the dynamic characteristics assessment experiment, which simulates foundation scour of the spread footing pier, foundation scour can be evaluated by the first mode natural frequency of the pier.

Modeling and Visualization of Flood Inundation in Natural River (자연하천의 홍수범람 모의 및 가시화)

  • Goh, Tae-Jin;Jung, Tae-Sung
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.3
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    • pp.157-164
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    • 2008
  • A modeling and visualization system of flood inundation in natural river, FloodViz, has been developed. Unsteady river flow and flood inundation are calculated by FLDWAV model. FLDWAV model and HEC-RAS model have been applied to a flood event at the same time to check model reliability. Simulation results of the two models showed good agreements. Flood propagation and inundation process can be analyzed accurately and easily by using visualization function of the FloodViz. Even though FloodViz users don't know well about both hydraulics and hydrology, they can understand flood inundation phenomena easily. This system can be used as a useful tool in forecasting flood inundation and observing the simulation results. Countermeasures for natural disaster prevention due to flood inundation can be established rapidly by using the FloodViz.

Experiments on the Influence of Opening of Natural Smoke Ventilators on the Stack Effect in High-rise Mixed-use Residential Buildings (초고층주상복합건물에서 배연창 개방이 연돌효과에 미치는 영향에 대한 실험적 연구)

  • Lim, Chae-Hyun;Kim, Bum-Gyu;Park, Yong-Hwan
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.3
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    • pp.89-94
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    • 2009
  • The stack effect in high-rise buildings is expected more significant at nights in winter due to the large temperature difference between the inside and outside of the buildings. However, the existence of large openings such as natural ventilators on the floor may effect the position of neutral plane, smoke spread at fire and thus obstruct the door openings for rescue. In this paper, the vertical and horizontal pressure distribution with different openings of natural smoke ventilators was experimentally analyzed by investigating pressure differentials.

재해로 인한 농작물의 생산비 피해액 산정

  • Shim, Kee-Oh;Lee, Cheol-Kyu
    • Journal of the Korean Society of Hazard Mitigation
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    • v.2 no.4 s.7
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    • pp.77-85
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    • 2002
  • Korean government compensates 100% for natural disaster relief fund to public facilities, and provides 70 percents to crops through unit price calculation. This study estimated disaster damage according to the standard production cost of crops. Disaster damage was estimated according to the unit price of crops. Those crops are lettuce, pumpkin, red pepper, spinach, tomato and cucumber. As a result, the ratio of natural disaster relief fund to damage was revealed as $3.3%{\sim}13.8%$ with present method, 5.7%{$\sim}34.1%$ with suggested method. Suggested method is the first one considered damage ratio of crops, producer price and raising period.

3D GSIS Application for Managing Flood Disaster (홍수재해관리를 위한 3차원 GSIS적용)

  • Yoo, Hwan-Hee;Kim, Uk-Nam;Kim, Seong-Sam;Chung, Dong-Ki
    • Journal of Korean Society for Geospatial Information Science
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    • v.12 no.1 s.28
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    • pp.21-29
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    • 2004
  • Floods are disastrous natural phenomena which result in numerous losses of life and property. It is possible to minimize the potential risk by adopting a disaster management system. Nowadays, Geo-Spatial Information System(GSIS) and computer-modelling techniques have assisted scientists and engineers with determining flood disaster assessments, GIS technologies especially have the advantage of performing spatial analysis as well as generating the model for a flood hazard. Therefore, this paper presents the flood management system based on 3D GSIS that can cope with natural disasters actively and manage flood hazard systematically by constructing the database using hydrological data, digital map, DEM, and high-resolution satellite images.

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