• 한국환경과학회지
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• 제14권6호
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• pp.621-627
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• 2005

It is analysised the causes and extent of damage of natural disasters through the investigating of natural disaster states occurred in Gyeongsangnam-do. The data for this study were based on disaster annual report between 1987 and 2003. Especially, the data between 1993 and 2003 were used for the analysis in Gyeongsangnam-do area. A typhoon and a heavy rain were the major causes of the natural disasters in Gyeongsangnam-do. For all that the extent of damage by a heavy rain was twice as much as that of a typhoon, Gyongsangnam-do suffered heavy damage from a typhoon. So, special attentions should be paid to establish prevention plans for that in this area. Also, half of the natural disasters were occurred between July and August, the intensive prevention plans for the summer season are needed.

• Smart Structures and Systems
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• 제29권1호
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• pp.1-16
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• 2022

Despite recent breakthroughs in deep learning and computer vision fields, the pixel-wise identification of tiny objects in high-resolution images with complex disturbances remains challenging. This study proposes a modified U-net for tiny crack segmentation in real-world steel-box-girder bridges. The modified U-net adopts the common U-net framework and a novel Self-Attention-Self-Adaption (SASA) neuron as the fundamental computing element. The Self-Attention module applies softmax and gate operations to obtain the attention vector. It enables the neuron to focus on the most significant receptive fields when processing large-scale feature maps. The Self-Adaption module consists of a multiplayer perceptron subnet and achieves deeper feature extraction inside a single neuron. For data augmentation, a grid-based crack random elastic deformation (CRED) algorithm is designed to enrich the diversities and irregular shapes of distributed cracks. Grid-based uniform control nodes are first set on both input images and binary labels, random offsets are then employed on these control nodes, and bilinear interpolation is performed for the rest pixels. The proposed SASA neuron and CRED algorithm are simultaneously deployed to train the modified U-net. 200 raw images with a high resolution of 4928 × 3264 are collected, 160 for training and the rest 40 for the test. 512 × 512 patches are generated from the original images by a sliding window with an overlap of 256 as inputs. Results show that the average IoU between the recognized and ground-truth cracks reaches 0.409, which is 29.8% higher than the regular U-net. A five-fold cross-validation study is performed to verify that the proposed method is robust to different training and test images. Ablation experiments further demonstrate the effectiveness of the proposed SASA neuron and CRED algorithm. Promotions of the average IoU individually utilizing the SASA and CRED module add up to the final promotion of the full model, indicating that the SASA and CRED modules contribute to the different stages of model and data in the training process.

• 한국방재학회 논문집
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• 제7권3호
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• pp.51-58
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• 2007

본 연구에서는 강원 지역에 거주하는 대학(원)생과 비거주하는 대학(원)생 750명을 대상으로 강원 지역의 재난특성, 방재의식 수준 등에 대한 조사를 수행하였다. 분석결과, 응답자 모두 강원 지역의 재난발생 가능성(74.0%)이 가장 높은 것으로 인식하는 것으로 나타났다. 강원도 거주자 군은 비거주자 군에 비해 풍수해와 산불 피해의 발생가능성이 높다고 인식하고 있는 것으로 나타났다. 강원도 지역에 재난이 많이 발생하는 원인은 불리한 자연조건, 방재시설의 부족, 지역주민의 방재의식 부족을 그 요인으로 인식하고 있는 것으로 조사되었다. 강원도 지역의 방재의식을 고취하기 위한 방법으로는 방재관련 시설의 확충과 방재관련 교육을 중요하게 인식하는 것으로 나타났다. 특히, 재난교육에 대한 경험이 없는 응답자가 전체의 62.1%로 조사되어 재난교육의 확대가 필요함을 알 수 있다.

• Wind and Structures
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• 제28권2호
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• pp.129-140
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• 2019

Accurately simulating the wind field of large-scale region, for instant urban areas, the locations of large span bridges, wind farms and so on, is very difficult, due to the complicated terrains or land surfaces. Currently, the regional wind field can be simulated through the combination of observation data and numerical model using observation-nudging in the Weather Research and Forecasting model (WRF). However, the main drawback of original observation-nudging method in WRF is the effects of observation on the surrounding field is fully mathematical express in terms of temporal and spatial, and it ignores the effects of terrain, wind direction and atmospheric circulation, while these are physically unreasonable for the turbulence. For these reasons, a spatial correlation-based observation-nudging method, which can take account the influence of complicated terrain, is proposed in the paper. The validation and comparation results show that proposed method can obtain more reasonable and accurate result than original observation-nudging method. Finally, the discussion of wind field along bridge span obtained from the simulation with spatial correlation-based observation-nudging method was carried out.

• 한국방재안전학회논문집
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• 제16권1호
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• pp.37-48
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• 2023

국토‧도시 공간 및 사회환경 변화, 기후변화로 인한 극한 기상현황, 자연재난에 따른 국가기반시설 마비 등으로 인해 초대형 재난 발생 가능성이 증가하고 있다. 본 연구에서는 미래 새로운 환경변화 상에 발생하는 미래형 재난에 대한 국토방재 전략의 체계적 수립을 지원하기 위하여, 미래형 재난에 대비한 국토방재 지능화 정책대안을 고찰하였다. 미래형 재난 관련한 국토환경 변화, 국토방재 관련 국내외 선행연구 및 정책동향, 국토 재난관리 시스템 관련 연구 등을 조사하고 제도적‧기술적 정책대안을 도출하였다. 제도적으로 미래형 재난에 대한 자기적응적 국토 조성을 체계화하고, 이를 기술적으로 지능형 의사결정 지원체계를 통해 지속적으로 지원해야 함을 정책적 대안으로 제시하였다.

• 한국해양공학회지
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• 제33권6호
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• pp.590-596
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• 2019

Numerous deaths and substantial property damage have occurred recently due to frequent disasters of the highest intensity according to the abnormal climate, which is caused by various problems, such as global warming, all over the world. Such large-scale disasters have become an international issue and have made people aware of the disasters so they can implement disaster-prevention measures. Extensive information on disaster prevention actively has been announced publicly to support the natural disaster reduction measures throughout the world. In Japan, diverse developmental studies on disaster prevention systems, which support hazard map development and flood control activity, have been conducted vigorously to estimate external forces according to design frequencies as well as expected maximum frequencies from a variety of areas, such as rivers, coasts, and ports based on broad disaster prevention data obtained from several huge disasters. However, the current reduction measures alone are not sufficiently effective due to the change of the paradigms of the current disasters. Therefore, in order to obtain the synergy effect of reduction measures, a study of the establishment of an integrated system is required to improve the various disaster prevention technologies and the current disaster prevention system. In order to develop a similar typhoon search system and establish a disaster prevention infrastructure, in this study, techniques will be developed that can be used to forecast typhoons before they strike by using artificial intelligence (AI) technology and offer primary disaster prevention information according to the direction of the typhoon. The main function of this model is to predict the most similar typhoon among the existing typhoons by utilizing the major typhoon information, such as course, central pressure, and speed, before the typhoon directly impacts South Korea. This model is equipped with a combination of AI and DNN forecasts of typhoons that change from moment to moment in order to efficiently forecast a current typhoon based on similar typhoons in the past. Thus, the result of a similar typhoon search showed that the quality of prediction was higher with the grid size of one degree rather than two degrees in latitude and longitude.

• 한국환경과학회지
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• 제14권6호
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• pp.613-619
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• 2005

Recently, we are suffered enormous loss from a natural disaster and making an effort to prepare measures for dealing with disasters. This study shows the major causes of natural disasters and stricken area with the analysis of meteorological data based on the Korean Meteorological Administration and the Central Disaster Relief Center records during 1987-2003 and classifies natural disasters according to the causes and damaged conditions. In this study, the most damaged area were Gangwon, Gyeongnam and Gyeongi province as a result of a typhoon and a localized heavy rain. To establish an effective disaster measure for these area, detailed prevention plans should be established by its causes after investigating precise regional damage data analysis.

• 한국환경과학회지
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• 제22권11호
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• pp.1529-1538
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• 2013

Disasters like mountain landslides and collapse in cutting areas claim many a life and cause economic losses, involving much effort and expenses for their recovery. This study has surveyed and analyzed incident of disasters that had occurred on the sloping sides in Korea for the past 13 years in an effort to relieve damage caused by disasters on the sloping sides. The analysis confirms that while the major cause of disasters on the sloping side was storms in the past, frequency of disasters on sloping sides caused by local downpour is steadily on the rise. In addition, while disasters were concentrated in Gangwon Province, a mountainous region of the country, frequency of disasters occurring on the sloping sides is steadily increasing recently on the sloping sides in downtown areas in Seoul, Gyeonggi-do and so forth, attributing a large percentage of disasters to sloping sides. Data surveyed and analyzed in this study are thought to be applicable as basic data for the establishment of effective measures for the prevention of disasters occurring on the sloping sides in the days to come.

• 한국방재학회 논문집
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• 제7권3호
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• pp.41-49
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• 2007

자연재해로부터 야기되는 피해를 줄이고 자연재해저감활동을 전개하기 위해서는 기상정보와 재해자료에 근거한 정확한 예보와 방재활동이 요구된다. 또한 사전방재활동을 위해서는 방재기상정보로의 처리가 필요하다. 이를 위하여 본 연구에서는 행정자치부에서 발행하는 통계연보와 재해연보, 중앙재해대책본부에서 발행한 최근 10년간 자연재해 피해 현황, 기상청에서 발행한 기상연보를 이용하였다. 이들 4가지 자료를 이용하여 자연재해의 원인과 피해요소, 발생빈도, 취약지역 등을 분석하였는데, 이들 자료는 피해내역과 기상현상에 대한 분류 및 용어가 일치하지 않으므로, 재해의 종류와 피해액을 비교 분석한 결과, 기상재해 원인과 피해 요소, 피해액, 피해지역 등과 같은 재해 변수를 선정하고, 재해연보를 이용하여 database를 구축하였다. 이렇게 구축된 database는 앞으로 자연재해 저감계획과 risk model을 개발하고 자연재해를 평가하는데 유용하게 쓰일 수 있다.

• 한국환경과학회지
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• 제15권11호
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• pp.1003-1010
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• 2006

It is very difficult to forecast accurately a damage from the natural disasters which occurs frequently. If the significant weather event was forecasted one or two days ago, we will be able to minimize a damage from the severe weather event through the suitable prevention activities. It said that 2000's our country's total damages from the meteorological disasters was several trillion won(Park et al, a, b, 2005). Therefore, we analyzed the Korea Meteorological Administration(KMA) and television broadcasting's reports, information contents, and transmission system, an ex post facto valuation about typhoon Nabi which struck the Korean peninsula from September 5 to 7, 2005. Through these investigations, we want to present the basic data to rises the application effect of disaster prevention meteorological information. We think KMA must present many information report to promote a citizen's understanding about the meteorological information and the serious disaster situation. And also we think the KMA and television broadcasting must present an advisable reports, the contents which is suitable to disaster response stages. And we must grasp the problem of disaster prevention meteorological information through an ex post facto examination, improve it effectively.