• 제목/요약/키워드: Flooding Area

검색결과 427건 처리시간 0.048초

Inplementation of flooding simulation in coastal area based on 3D satellite images and Web GIS

  • Jo, Myung-Hee;Park, Hyeon-Cheol;Kim, Hyoung-Sub;Choi, Yong-Ki
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.166-169
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    • 2006
  • Our country's coast is vulnerable area to natural disaster which the repetitive damages occur every year including a loss of lives, the damage of facilities and erosion mostly except for the east coast because of a typhoon, tidal waves, sea water overflowing by topographic structure of low-lying gentle slope and shallow sea. However, as for prevention of natural disaster occurring every year, the situation is that it's centered on the restorationcentered measures and the general disaster prevention research to minimize damages at the time of disaster occurrence is insufficient. This study intendedlop t to devehe techniques possible for real time sampling of damage prediction areas on Web in order to support decision making for damage prevention and establishment of disaster prevention policy. For this, the thematic map was produced related to disaster based on high-resolution satellite picture, and the environmental DB similar to real world was constructed through topographic construction of three-dimension integrating the parts of land and the sea. In addition, the system was developed possible for the expression of damageable regions by real time grasp of dangerous regions at the time of disaster occurrence through over flowing simulation of three-dimension, and it's intended to prepare a basis to minimize damages to disaster situations through it.

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A study of aerodynamic pressures on elevated houses

  • Abdelfatah, Nourhan;Elawady, Amal;Irwin, Peter;Chowdhury, Arindam
    • Wind and Structures
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    • 제31권4호
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    • pp.335-350
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    • 2020
  • In coastal residential communities, especially along the coastline, flooding is a frequent natural hazard that impacts the area. To reduce the adverse effects of flooding, it is recommended to elevate coastal buildings to a certain safe level. However, post storm damage assessment has revealed severe damages sustained by elevated buildings' components such as roofs, walls, and floors. By elevating a structure and creating air gap underneath the floor, the wind velocity increases and the aerodynamics change. This results in varying wind loading and pressure distribution that are different from their slab on grade counterparts. To fill the current knowledge gap, a large-scale aerodynamic wind testing was conducted at the Wall of Wind experimental facility to evaluate the wind pressure distribution over the surfaces of a low-rise gable roof single-story elevated house. The study considered three different stilt heights. This paper presents the observed changes in local and area averaged peak pressure coefficients for the building surfaces of the studied cases. The aerodynamics of the elevated structures are explained. Comparisons are done with ASCE 7-16 and AS/NZS 1170.2 wind loading standards. For the floor surface, the study suggests a wind pressure zoning and pressure coefficients for each stilt height.

GIS와 FLUMAN을 이용한 남강 저지대 침수분석에 관한 연구 (A Study on the Inundation Analysis of the Nam River Lowland Using GIS and FLUMAN)

  • 최현
    • 대한공간정보학회지
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    • 제25권2호
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    • pp.49-56
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    • 2017
  • 본 연구에서는 이상기후 및 기후변화에 따른 태풍, 집중호우 등으로 발생할 수 있는 피해들을 대비하고 상황에 맞는 대응을 위한 침수분석을 하였다. 연구대상지역은 낙동강의 지류인 남강유역에 대하여 국 내외 홍수위험지도 작성에 널리 이용되고 있는 FLUMEN 모형을 적용한 하도 및 제내지의 2차원 침수해석을 실시하였다. ArcView에 의해 지형을 $5m{\times}5m$의 수치표고모형을 생성하여 하천의 수리 수문특성 분석 및 침수지역 식별의 정확성을 최대한 확보할 수 있도록 하였다. 침수 모의 결과 1구역에 163.3 ha, 2구역에 227.7ha 그리고 3구역은 59.9 ha의 침수가 발생한 것으로 모의되었다.

Extraction of water body in before and after images of flood using Mahalanobis distance-based spectral analysis

  • Ye, Chul-Soo
    • 대한원격탐사학회지
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    • 제31권4호
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    • pp.293-302
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    • 2015
  • Water body extraction is significant for flood disaster monitoring using satellite imagery. Conventional methods have focused on finding an index, which highlights water body and suppresses non-water body such as vegetation or soil area. The Normalized Difference Water Index (NDWI) is typically used to extract water body from satellite images. The drawback of NDWI, however, is that some man-made objects in built-up areas have NDWI values similar to water body. The objective of this paper is to propose a new method that could extract correctly water body with built-up areas in before and after images of flood. We first create a two-element feature vector consisting of NDWI and a Near InfRared band (NIR) and then select a training site on water body area. After computing the mean vector and the covariance matrix of the training site, we classify each pixel into water body based on Mahalanobis distance. We also register before and after images of flood using outlier removal and triangulation-based local transformation. We finally create a change map by combining the before-flooding water body and after-flooding water body. The experimental results show that the overall accuracy and Kappa coefficient of the proposed method were 97.25% and 94.14%, respectively, while those of the NDWI method were 89.5% and 69.6%, respectively.

2000년 강원도 동해안지역 대규모 산불화재가 태풍루사 홍수피해에 미친 영향 -삼척시 오십천을 중심으로 (A Study on the Flood Damage Assessment by Typhoon RUSA in the East Coast of Kangwon Prefecture Following the 2000 Large Scale Fire Disaster -Focused on the Watershed of Oship River, Samcheok City)

  • 강상혁
    • 한국화재소방학회논문지
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    • 제17권4호
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    • pp.70-75
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    • 2003
  • 강원 동해안 지역은 산불과 홍수와 같은 재해가 빈번하게 발생되어 왔다. 2000년 4월 대규모 산불의 발생으로 산림은 소실되고 황폐화 되었다. 더욱이 2002년 8월 31일 일강우량 315 mm를 동반한 태풍 루사로 인하여 178명의 인명피해와 막대한 재산피해를 경험하게 되었다. 따라서 본 연구에서는 실제 피해지역의 현장조사를 통하여 산불재해를 고려한 홍수피해의 원인을 규명하고자 하였다.

항공기 안전 운항에 영향을 미치는 중규모 대류계 사례 연구(I) (A study of Mesoscale Convective Systems(MCSs) event impacts on the safe operation of aircraft(I))

  • 김영철
    • 한국항공운항학회지
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    • 제22권1호
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    • pp.76-84
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    • 2014
  • Heavy Rainfall event accompanying with Mesoscale Convective Systems(MCSs) inducing flash flooding and Kimpo and Inchon International Airport closing over Seoul metropolitan area was investigated this study. This heavy rainfall event was occurred through the synoptic scale boundary of North Pacific Subtropical high, Typhoon and also can predicted by proper analysis of various forecasting parameters such as abundant moisture, instabilities, and synoptic/mesoscale forcing.

관개 논에서의 영양물질 추정 모형의 개발 (Development of CREAMS-PADDY Model for Simulating Pollutants from Irrigated Paddies)

  • 서춘석;박승우;김상민;강문성;임상준;윤광식
    • 한국농공학회지
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    • 제44권3호
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    • pp.146-156
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    • 2002
  • The objective of this study was to develop a modified CREAMS model for paddy field conditions. The model simulates daily balance of water and nutrient from irrigated paddies using meteorological, irrigation, and agricultural management data. The model simulates daily evapotranspiration of paddy using Penman equation and determines daily flooding depth changes. Total nitrogen and phosphorus concentrations within flooding water, surface runoff, and leaching water from a paddy field also can be simulated. Parameters of the model were calibrated using observed data of the Agricultural Experiment Station of the Seoul National University in Suwon Korea. The model was applied for the irrigation period of paddy field in Gicheon area when 1,234 mm annual rainfall was occurred. The simulated losses of the total nitrogen and total phosphorous were 11.27 kg/ha and 0.98 kg/ha, respectively. There was a good agreement between observed and simulated data. It was found that CREAMS-PADDY model was capable of predicting runoff and nutrient losses from irrigated paddy fields.

Probabilistic Broadcasting Based on Selfishness and Additional Coverage in MANETs

  • Kim, Jae-Soo;Kim, Jeong-Hong
    • Journal of information and communication convergence engineering
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    • 제10권4호
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    • pp.329-336
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    • 2012
  • For designing broadcast protocols in mobile ad hoc networks (MANETs), one of the important goals is to reduce the rebroadcast packets redundancy while reaching all the nodes in network. In this paper, we propose a probabilistic broadcasting mechanism based on selfishness and additional coverage in MANETs. Our approach dynamically adjusts the rebroadcast probability according to the extra covered area and number of neighbor nodes. By these two factors, mobile hosts can be classified into three groups: normal, low selfishness, and high selfishness groups. The nodes in the normal group forward packets for other nodes with high probability, whereas the nodes in the low selfishness group rebroadcast packets with low probability and the nodes in the high selfishness group do not rebroadcast packets. We compared our approach with simple flooding and the fixed probabilistic approach. The simulation results show that the proposed schemes can significantly reduce the number of retransmissions by up to 40% compared simple flooding and fixed probabilistic scheme without significant reduction in the network reachability and end-to-end packet delay.