• Title/Summary/Keyword: localized heavy rain

Search Result 74, Processing Time 0.024 seconds

Research on flood risk forecast method using weather ensemble prediction system in urban region (앙상블 기상예측 자료를 활용한 도시지역의 홍수위험도 예측 방안에 관한 연구)

  • Choi, Youngje;Yi, Jaeeung
    • Journal of Korea Water Resources Association
    • /
    • v.52 no.10
    • /
    • pp.753-761
    • /
    • 2019
  • Localized heavy storm is one of the major causes of flood damage in urban regions. According to the recent disaster statistics in South Korea, the frequency of urban flood is increasing more frequently, and the scale is also increasing. However, localized heavy storm is difficult to predict, making it difficult for local government officials to deal with floods. This study aims to construct a Flood risk matrix (FRM) using ensemble weather prediction data and to assess its applicability as a means of reducing damage by securing time for such urban flood response. The FRM is a two-dimensional matrix of potential impacts (X-axis) representing flood risk and likelihood (Y-axis) representing the occurrence probability of dangerous weather events. To this end, a regional FRM was constructed using historical flood damage records and probability precipitation data for basic municipality in Busan and Daegu. Applicability of the regional FRMs was assessed by applying the LENS data of the Korea Meteorological Administration on past heavy rain events. As a result, it was analyzed that the flood risk could be predicted up to 3 days ago, and it would be helpful to reduce the damage by securing the flood response time in practice.

Statistical Estimate Technique of Cut Slope Stability (깎기비탈면 안정성의 통계적 예측기법)

  • Lee, Moon-Se;Shin, Chang-Gun;Jeon, Kuk-Jae;Lee, Seung-Woo
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.09a
    • /
    • pp.727-735
    • /
    • 2010
  • The collapse of cut slope near national roads in Korea mostly occurs in every summer when typhoon or localized heavy rain comes. Such collapse brings about a loss of many lives and property and recently the damage is on rapidly increasing trend. Therefore, we may reduce the loss of many lives and property in great deals if we can predict and prepare for the collapse of cut slope. However, it is not easy to predict collapse because there are many factors causing collapse in combination and all they have different levels of contribution. Therefore, this study completed prediction formula by using a statistic technique for quantitative analysis on the interaction of those factors so as to predict the stability of slopes. Consequently, it is judged that effective slope management will be possible by selecting dangerous slopes quantitatively among cut slopes near national roads and by preparing for the collapse in advance.

  • PDF

Revision of Agricultural Drainage Design Standards (농업생산기반정비사업 계획설계기준 배수편 개정)

  • Kim, Kyoung Chan;Kim, Younghwa;Song, Jaedo;Chung, Sangok
    • KCID journal
    • /
    • v.21 no.1
    • /
    • pp.32-44
    • /
    • 2014
  • In Korea, global warming caused by the climate changes impacted on weather system with increase in frequency and intensity of precipitation, and the rainfall pattern changes significantly by regional groups. Furthermore, it is expected that the regional and annual fluctuation ranges of the rainfall in the future would be more severe. Nowadays, agricultural drainage system designed by the existing standard of 20-year return period and 2 days of fixation time cannot deal with the increment rainfall such as localized heavy rain and local torrential rainfalls. Therefore, it is required to reinforce the standard of the drainage system in order to reduce the agricultural flood damage brought by unusual weather. In addition, it is needed to improve the standard of agricultural drainage design in order to cultivate farm products in paddy fields as facility vegetable cultivation and up-land field crop have been damaged by the moisture injury and flooding. In order to prepare for the changes of rainfall pattern due to climate changes and improve the agricultural drainage design standards by the increase of cultivating farm products, the purpose of this study is to examine the impact of climate changes, the changes of relative design standard, and the analytic situation of agricultural flood damages, to consider the drainage design standard revision, and finally to prepare for enhanced agricultural drainage design standards.

  • PDF

Development of the Damage Investigation Item to Debris Flow using the Delphi Method (델파이 기법을 활용한 토석류 피해조사 항목 개발)

  • Byun, Yo Seph;Kim, Min Gi;Park, Kyung Han;Oh, Tae Keun;Seong, Joo Hyun
    • Journal of the Korean Society of Safety
    • /
    • v.31 no.2
    • /
    • pp.41-48
    • /
    • 2016
  • Recently, the frequency and intensity of localized heavy rain and typhoon due to the abnormal climate has increased, and especially the damage by an avalanche of earth and rocks similar to the landslide of Umyeon Mountain has become a social issue. However, the standardized damage investigation method doesn't yet exist, so the systematic analysis of the data has not been carried out. In this regard, this study developed assessment items to conduct standardized damage investigation of debris flow. To achieve this, preliminary assessment items were derived from analysis of literature review and the Delphi technique of 12 experts who are engaged in research facility, academia and industry was conducted. As a result, 29 assessment items which can be classified into 6 groups were determined. Surveying the relevant hand-on workers, details assessment items in each group were determined by exploratory factor analysis and reliability analysis.

Estimation of Movement Amount of River Floating Debris Based on Effective Rainfall and Flow Rate (유효강우량과 유량에 따른 하천 부유쓰레기 이동량 산출)

  • Jang, Seon-Woong;Yoon, Hong-Joo
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.12 no.1
    • /
    • pp.237-242
    • /
    • 2017
  • Along with effluence of non-point pollution source, continuous precipitation due to rainy season or localized heavy rain can also be a good reason for increase of flow rate. And if the water level is going up due to the increase, floating debris around rivers and streams will move because of increased flow velocity. However, currently, there are no studies which perform quantitative calculation on movement of floating debris by analyzing amount of rainfall and flow rate in both domestic and abroad. Thus, the present study calculated amount of movement of floating debris based on moving route monitoring results according to changes of effective rainfall and flow rate that are obtained by using SCS-CN method.

Development of Unmanned Irrigation Technology Using Five Senses During the Disconnection of Communication Due to Disasters (재난재해로 인한 통신두절시 오감기술을 이용한 무인 수처리 기술 개발)

  • Kim, Jae-Yeol;You, Kwan-Jong;Jung, Yoon-Soo;Ahn, Tae-Hyoung
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.16 no.1
    • /
    • pp.141-148
    • /
    • 2017
  • Recently, localized heavy rain storms have been occurring frequently due to global warming, and it is difficult to shield a large number of facilities against disaster with limited manpower. The unmanned water treatment system uses five senses to analyze various judgment criteria, which are set according to field situations such as machine vibrations, the temperature of bearings, the sound of the operating machines, and the hydraulic pressure, current, and voltage of the hydraulic floodgates. It thus judges normal or abnormal operation status and conducts unmanned control of such machines. It automatically applies a system to the interruption of communications and therefore improves the reliability of its unmanned irrigation facilities. It maximizes the operational efficiency of managers responsible for various fields, enabling them to discharge water before the situation escalates to a crisis within the golden time, and to protect against damage to humans and property.

Development of Rivers Management system to Decrease flood Disaster using GIS (GIS 기반의 홍수 피해 감소를 위한 하천관리 시스템 개발)

  • Jeong, In-Ju;Park, Sang-Ju;Kim, Sang-Yong
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.11 no.3 s.26
    • /
    • pp.35-40
    • /
    • 2003
  • In these days, damages from localized heavy rain or typhoon are increase and people are making constant effort to work out countermeasures. Especially, by apply GIS with prompt extraction of information and objective analysis, we could demonstrate more effectively. For that reason, in this research we make the connection between rainfall-runoff model and HEC-RAS which calculate automatically and inquire out the dangerous zone easier way by describing the result with the connection between the Map Object and MFC. Most of all, this research will be very useful to forecast and prepare the disaster because it could plot plane figures, longitudinal sections and cross sections at the same time to help understand the damaged situation.

  • PDF

Effect of watershed characteristics on the criteria of Flash Flood warning (유역인자의 특성이 경계경보발령 기준에 미치는 영향분석)

  • 양인태;김재철;김태환
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2004.11a
    • /
    • pp.389-392
    • /
    • 2004
  • A recent unusual change in the weather is formed as a localized heavy rain in a short time. This phenomenon has caused a flash flood, and flash floods extensively have damaged human lives many times. In large river's case, the extent of loss of lives and properties has been decreased through the flood warning system by flood control stations of each stream. However, the extent of damage in other small rivers has increased reversely. Therefore, it is necessary to establish a new flood warning system against flash floods instead of the existing flood warning system. It is a specific character that the damage from flash floods in mountain streams brings much more loss of lives than large river's flood. The purpose of this study is calculating the characteristic of flash floods in streams, analyzing topographical characteristics of water basin through applying GIS techniques with the calculation as mentioned above and researching what topographical conditions have influence on hydrological flash floods in water basin. The flash flood prediction model we used is made by GIUH (geomorphoclimatic instantaneous unit hydrograph) with hydrologic-topographical technology. As applying the flash flood prediction model, this is a procedure for calculating topographical information in basin: we made a topological data up out of database with utilizing GIS, and we also produced a DEM (digital elevation model) and used it as a topographical data for determining amount of flash floods.

  • PDF

Characterization of Cemented Sand for Building of Levee (하천제방축조재료로서 시멘트혼합토의 특성)

  • Jeong, Woo-Seob;Kim, Yung-Su
    • Journal of the Korean Society of Hazard Mitigation
    • /
    • v.6 no.4 s.23
    • /
    • pp.29-36
    • /
    • 2006
  • There are loss of lives and properties in many areas of the basin of the Nak-Dong river by the unusual weather and the localized heavy rain recently, and many difficulties of levee construction for prevention of disasters by acquisition of material and expensive transportation. In this research, The factors and causes which affect the strength through laboratory tests about the cemented sand that is mixed a few portland cement and sand of Nak-Dong river bed was researched closely. For providing the fundamental data which is needed in design and analysis of levee material, the compaction test and the standard triaxial compression test etc was conducted., analyzed compression strength and characteristic of stress-strain behavior in which the influence of cement content.

A study on the Stability Analysis of Slope in Unsaturated Soil Based on the Soil-Water characteristic curve (함수특성곡선을 고려한 불포화토 사면의 안정성 연구)

  • Yoon, Min-Ki;Kim, Jong-Sung;Kim, Hyo-Jung;Lee, Yeong-Saeng
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.1029-1037
    • /
    • 2008
  • The finite element analysis of transient water flow through unsaturated soils was used to investigate effects of hydraulic characteristics, initial relative degree of saturation, methods to consider boundary condition, and rainfall intensity and duration on water pressure in slopes. The finite element method with shear strength reduction technique was used to evaluate the stability of slopes under rainfall. The slope-related disasters in Korea usually occur between July and September during the typhoon and localized heavy rain. This means that the rainfall is the most important factor that leads to the slope-related disasters. The slope-related disasters can happen at very short time and lead to big damage. To forecast the change of the heave of the groundwater in slope the Seep/w program was used.

  • PDF