농업시설물에 대한 화산재 취약도 평가

함희정,최승훈,이승수,김호정,Ham, Hee Jung,Choi, Seung Hun,Lee, Sungsu,Kim, Ho-Jeong 한국전산구조공학회 2014 한국전산구조공학회논문집 Vol.27 No.6

본 연구에서는 농업시설물 중 내재해형 비닐하우스와 축사에 대한 화산재 취약도를 평가하였다. 이들 농업시설물에 대한 화산재 취약도를 평가하기 위해 화산재 하중의 확률밀도함수와 대상 시설물 저항성능의 확률밀도함수를 비교하는 해석적 접근법 기반의 FOSM(first-order second-moment) 방법이 이용되었다. 화산재 취약도 평가를 위하여 폭과 높이 그리고 단면 및 재료적 특성이 상이한 6종의 내재해형 비닐하우스와 표준형, 해안형, 산간형으로 구분된 3종의 축사가 사용되었다. 또한 FOSM 방법으로 평가된 내재해형 비닐하우스와 축사의 취약도는 GEV(generalized extreme value) 분포함수의 모수 형태로 최적화된 후 데이터베이스화되었다. 본 연구에서 평가한 화산재 취약도는 백두산 화산분화에 따른 화산재 퇴적에 대한 농업시설물의 위험도 평가를 위하여 활용될 수 있다. This paper presents findings from the assessment of the volcanic ash fragility for multi-hazard resisting vinyl greenhouse and livestock shed among the agricultural facilities. The volcanic ash fragility was evaluated by using a combination of the FOSM (first-order second-moment) method, available statistics of volcanic load, facility specifications, and building code. In this study, the evaluated volcanic ash fragilities represent the conditional probability of failure of the agricultural facilities over the full range of volcanic ash loads. For the evaluation, 6 types(ie., 2 single span, 2 tree crop, and 2 double span types) of multi-hazard resisting vinyl greenhouses and 3 types(ie., standard, coast, and mountain types) of livestock sheds are considered. All volcanic ash fragilities estimated in this study were fitted by using parameters of the GEV(generalized extreme value) distribution function, and the obtained parameters were complied into a database to be used in future. The volcanic ash fragilities obtained in this study are planning to be used to evaluate risk by volcanic ash when Mt. Baekdu erupts.

통계적 축소법을 이용한 미래 풍속의 평가

함희정,이승수,김호정,Ham, Hee-Jung,Lee, Sung-Su,Kim, Ho-Jeong 대한건축학회 2011 대한건축학회논문집 Vol.27 No.12

In this paper, a statistical downscaling methodology is developed to investigate its applicability in downscaling wind speeds over South Korea. The investigation includes calibration of the statistical downscaling model by using large-scale atmospheric variables encompassing NCEP/NCAR reanalysis data, validation of the model for the calibration period, and prediction of the future regional wind speed scenario based on the general circulation model (GCM) outputs of scenario A1B of the CGCM3. Selected as climate variables for downscaling were measured daily wind speed data (1971~2000) from 8 weather stations over South Korea. The results show that: (1) There exists a close relationship between the observed and the simulated daily wind speeds during the calibration period of 1971~2000. (2) Under the scenario A1B, during the prediction period of 2011~2100, effects of climate change influencing on the daily mean and 10 minute maximum mean wind speeds are expected, and these effects are different from region to region over South Korea. (3) However, based on the scenario A1B of the CGCM3, the potential impacts of climate change on the surface wind speed is relatively minor, and the current design wind velocity may not need to be changed for the predicted period.

경량 목구조 지붕 쉬딩 시스템에 대한 강풍 취약도 평가기법 개발

함희정,이승수,김호정,Ham. Hee Jung,Lee. Sungsu,Kim. Ho-Jeong 한국방재학회 2012 한국방재학회논문집 Vol.12 No.6

본 논문에서는 강풍 지역에 건설된 경량 목구조 건축물의 취약도 구축 방안이 연구되었다. 강풍 취약도를 구축하기 위하여 경량 목구조 건축물에 작용하는 풍하중과 지붕 쉬딩 시스템의 저항 성능이 비교되었다. 본 연구는 지붕 쉬딩 시스템에 대한 강풍 취약도 모형을 파악 가능한 쉬딩의 저항성능과 최근의 구축된 풍하중의 통계치 및 기준을 사용하여 개발하는 것에 목적을 갖는다. 본 연구에서는 지리적으로 상이한 위치에 건설된 일반적 형태의 건축물에 대한 취약도를 몬테카를로 모사모형을 기반으로 연구하였으며, 강풍 취약도는 3가지 손상 정도를 고려하여 3초 돌풍의 함수로 개발되었다. 본 연구에서 기술한 취약도 평가방법은 강풍 지역에 건설된 경량 목구조 건축물에 대한 물리적 취약정도 및 경제적 피해 평가 방안으로 사용될 수 있을 것으로 사료된다. This paper presents a fragility assessment for roof sheathing in light-frame wood constructions built in high wind regions. A fragility methodology is developed to assess the performance of roof sheathing subjected to wind-induced building pressures. The goal of this study is to develop a fragility model for roof sheathing system using available resistance test data, recently developed wind load statistics and building code. A typical baseline building considering different geographic locations is investigated using a Mote Carlo simulation method. Fragilities of the baseline building considering three different levels of damages are developed as a function of 3 second gust wind speed. The fragility methodology described in this paper can be used to estimate physical vulnerability and financial loss of light-frame wood construction in high wind regions.

POD 기법과 풍진동 데이터를 이용한 고층구조물의 모드식별

함희정(Ham Hee-Jung),김형기(Kim Hyong-Kee) 대한건축학회 2009 大韓建築學會論文集 : 構造系 Vol.25 No.4

In this paper, the Proper Orthogonal Decomposition (POD) method, which is a statistical analysis technique to find the dynamic characteristics of a random field, is adapted to identify the modal parameters of a tall chimney structure. A wind force time history, which is applied to the structure, is obtained by a wind tunnel test of a scale down model. The POD method is applied on the wind force induced responses of the structure, and the true normal modes of the structure are obtained. The modal parameters including, natural frequency, mode shape, damping ratio and kinetic energy of the structure can be estimated accurately by using the POD method. With these results, it may be concluded that the POD method can be applied to obtain accurate modal parameters from the wind-induced structural responses.

통계적 축소법을 이용한 미래 풍속의 평가

함희정(Ham, Hee-Jung),이승수(Lee, Sung-Su),김호정(Kim, Ho-Jeong) 대한건축학회 2011 大韓建築學會論文集 : 構造系 Vol.27 No.12

In this paper, a statistical downscaling methodology is developed to investigate its applicability in downscaling wind speeds over South Korea. The investigation includes calibration of the statistical downscaling model by using large-scale atmospheric variables encompassing NCEP/NCAR reanalysis data, validation of the model for the calibration period, and prediction of the future regional wind speed scenario based on the general circulation model (GCM) outputs of scenario A1B of the CGCM3. Selected as climate variables for downscaling were measured daily wind speed data (1971~2000) from 8 weather stations over South Korea. The results show that: (1) There exists a close relationship between the observed and the simulated daily wind speeds during the calibration period of 1971~2000. (2) Under the scenario A1B, during the prediction period of 2011~2100, effects of climate change influencing on the daily mean and 10 minute maximum mean wind speeds are expected, and these effects are different from region to region over South Korea. (3) However, based on the scenario A1B of the CGCM3, the potential impacts of climate change on the surface wind speed is relatively minor, and the current design wind velocity may not need to be changed for the predicted period.

화산재 퇴적에 의한 농작물의 생산량 손실 예측

함희정(Ham Hee Jung),최승훈(Choi Seung Hun),윤우석(Yun Wooseok),이승수(Lee Sungsu) 한국방재학회 2017 한국방재학회논문집 Vol.17 No.2

본 연구에서는 화산재 퇴적에 의한 농작물의 생산량 손실을 예측하였다. 이를 예측하기 위하여 2006년 인도네시아 머라피(Merapi) 화산분화 시 농작물에서 관측된 피해영향 자료를 기초로 화산재 취약도를 개발하고, 2015년 농작물 생산통계를 기반으로 농작물의 연간 생산량을 파악하였다. 또한, 농작물의 계절별 취약성을 고려하기 위하여 네 가지의 계절적 영향계수(0.00, 0.25, 0.75, 1.00)를 정의하였다. 본 논문에서는 예측된 농작물의 생산량 손실 중 강원도 지역 농작물을 예시로 제시하였다. 본 연구로부터 화산재 퇴적두께가 증가함에 따라 강원도에서 재배되는 농작물에 대하여 최대 90% 이상의 손실률이 발생되는 것을 확인할 수 있었다. 본 연구에서 개발된 농작물의 생산량 손실 예측 알고리즘은 백두산과 한반도 주변국 화산분화 시 발생할 수 있는 잠재적 위험도 또는 손실을 평가하기 위하여 활용될 예정이다. This paper presents a prediction of production loss for agricultural crops induced by volcanic ash deposition. Production losses of agricultural crops were predicted by using the volcanic ash fragility, annual yield, and seasonality coefficient of agricultural crops. The volcanic ash fragility of agricultural crops was developed by using observed damage data from the 2006 eruption of Merapi volcano in Indonesia. Annual yields of agricultural crops were obtained from the 2015 statistics for production of agricultural crops in South Korea. Seasonality coefficient of agricultural crops was defined by 4 types (0.00, 0.25, 0.75, and 1.00) with considering cultivation time for each object crop. This paper only shows the prediction of production loss for 24 agricultural crops in Gangwon province as an example. From the prediction, it is found that production loss ratio of agricultural crops can be reached more than 90 % as volcanic ash deposition increases. The algorithm of production loss on agricultural crops established in this study can be applied to evaluate potential losses or risks from volcanic eruptions around the Korean Peninsula.

샌드위치 패널을 적용한 산업시설물에 대한 강풍취약도 개발

함희정(Ham Hee-Jung),이승수(Lee Sung-Su),김호정(Kim Ho-Jeong) 대한건축학회 2009 大韓建築學會論文集 : 構造系 Vol.25 No.12

In this paper, a fragility analysis methodology is developed for assessing the response of steel-framed industrial buildings exposed to extreme wind conditions. This fragility is a conditional limit state probability, presented as a function of the 3-second gust wind speed, based on a relation between statistics of wind loads and building resistances. Six different baseline industrial buildings considering different roof shapes and geographic locations were investigated using a probabilistic approach. The fragility methodology described in this paper can be used to develop performance-based design guidelines for industrial buildings in high wind regions as well as to provide information on which to base structural performance or expected loss assessments.

CGCM3 전지구모형에 의한 한반도 미래 일평균 풍속의 평가

함희정(Ham, Hee-Jung) 강원대학교 산업기술연구소 2013 産業技術硏究 Vol.33 No.1

A statistical downscaling methodology has been developed to investigate future daily wind speeds over South Korea. This methodology includes calibration of the statistical downscaling model by using large-scale atmospheric variables encompassing NCEP/NCAR reanalysis data, validation of the model for the calibration period, and estimation of the future wind speed based on the general circulation model (GCM) outputs of scenario A1B of the CGCM3. Based on the scenario A1B of the CGCM3 model, the potential impacts of climate change on the daily surface wind speed is relatively small (+/- 1m/s) in South Korea.

통계적 축소법을 이용한 한반도 인근해역의 미래 표층수온 추정

함희정(Ham, Hee-Jung),김상수(Kim, Sang-Su),윤우석(Yoon, Woo-Seok) 강원대학교 산업기술연구소 2011 産業技術硏究 Vol.31 No.1

Recently, climate change around the world due to global warming has became an important issue and damages by climate change have a bad effect on human life. Changes of Sea Surface Temperature(SST) is associated with natural disaster such as Typhoon and El Nino. So we predicted daily future SST using Statistical Downscaling Method and CGCM 3.1 A1B scenario. 9 points of around Korea peninsular were selected to predict future SST and built up a regression model using Multiple Linear Regression. CGCM 3.1 was simulated with regression model, and that comparing Probability Density Function, Box-Plot, and statistical data to evaluate suitability of regression models, it was validated that regression models were built up properly.

Proper orthogonal decomposition 기법을 이용한 세장한 구조물의 모드인자 파악

함희정(Ham Hee Jung) 강원대학교 산업기술연구소 2008 産業技術硏究 Vol.28 No.1

In this paper, the Proper Orthogonal Decomposition (POD) method, which is a statistical analysis technique to find the modal characteristics of a structure, is adapted to identify the modal parameters of a tall chimney structure. A wind force time history, which is applied to the structure, is obtained by a wind tunnel test of a scale down model. The POD method is applied on the wind force induced responses of the structure, and the t겨e normal modes of the structure can be obtained. The modal parameters including, natural frequency, mode shape, damping ratio and kinetic energy of the structure can be estimated accurately. With these results, it may be concluded that the POD method can be applied to obtain accurate modal parameters from the wind-induced building responses.