PURPOSES : Recently, air pollution due to fine particulate matter has been increasing in Korea. Nitrogen oxides (NOx) are particulate matter precursors significantly contributing to air pollution. Increasing efforts have been dedicated to NOx removal from air, since it is particularly harmful. Application of titanium dioxide (TiO2) for concrete road structures is a suitable alternative to remove NOx. As the photocatalytic reaction of TiO2 is the mechanism that eliminates NOx, the ultraviolet rays in sunlight and TiO2 in existing concrete structures need to be contacted for the reaction process. For the application of vertical concrete road structures such as retaining walls, side ditches, and barriers, a pressurized TiO2 fixation method has been developed considering the pressure and pressurization time. In this study, longterm serviceability and repeatability were investigated on concrete specimens applying the dynamic pressurized TiO2 fixation method. Additionally, the environmental hazards of nitrate adsorbed on TiO2 particles were evaluated. METHODS : Concrete specimens to simulate roadside vertical concrete structures were manufactured and used to evaluate the long-term serviceability and repeatability of the dynamic pressurized TiO2 fixation method. The NOx removal efficiency was measured using NOx evaluation equipment based on ISO 22197-1. In addition, the nitrate concentration was measured using a comprehensive water quality analyzer for evaluating environmental hazards. RESULTS : As the experiment to evaluate the NOx removal efficiency of the dynamic pressurized TiO2 fixation method progressed from one to seven cycles, the nitrate concentration increased from 2.35 mg/L to 3.06 mg/L, and the NOx removal efficiency decreased from 53% to 25%. After seven cycles of NOx removal efficiency evaluation, the average nitrate concentration was 3.06 mg/L. The nitrate concentration collected immediately after the NOx removal efficiency test for each cycle was in the range of 2.51 to 2.57 mg/L. By contrast, it was confirmed that the nitrate concentration was lowered to approximately 2.1 mg/L when the surface was washed with water. CONCLUSIONS : The NOx removal efficiency was maintained at over 25% even after seven cycles of NOx removal efficiency evaluation, securing long-term serviceability. In addition, the harmful effects on the environment and human health are insignificant, since the nitrate concentration was less than 10 mg/L, in accordance with domestic and foreign standards. Practical applicability of the pressurized TiO2 fixation method was established by evaluating the long-term serviceability, repeatability, and environmental hazards.
A connected control method for the adjacent buildings has been studied to reduce dynamic responses. In these studies, seismic loads were generally used as an excitation. Recently, multi-hazards loads including earthquake and strong wind loads are employed to investigate control performance of various control systems. Accordingly, strong wind load as well as earthquake load was adopted to evaluate control performance of adaptive smart coupling control system against multi-hazard. To this end, an artificial seismic load in the region of strong seismicity and an artificial wind load in the region of strong winds were generated for control performance evaluation of the coupling control system. Artificial seismic and wind excitations were made by SIMQKE and Kaimal spectrum based on ASCE 7-10. As example buildings, two 20-story and 12-story adjacent buildings were used. An MR (magnetorheological) damper was used as an adaptive smart control device to connect adjacent two buildings. In oder to present nonlinear dynamic behavior of MR damper, Bouc-Wen model was employed in this study. After parametric studies on MR damper capacity, optimal command voltages for MR damper on each seismic and wind loads were investigated. Based on numerical analyses, it was shown that the adaptive smart coupling control system proposed in this study can provide very good control performance for Multi-hazards.
암반지반에 주어진 등재해도 스펙트럼에 상응하는 원전부지 토사지반에서의 등재해도 스펙트럼을 도출하기 위한 확률론적 방법론을 제시하였다. 이를 위해 지진 운동 및 지반의 불확실성을 고려한 지반응답 해석을 통해 토사지반 지표에서의 지진동 증폭계수를 산정하였다. 증폭계수는 가장 상관관계가 높은 지반운동의 스펙트럴 가속도 규모와의 회귀분석을 통해 계산되었다. 이 방법론을 적용하여 국내 KNGR (Korean Next Generation Reactor) 및 APR1400 (Advanced Power Reactor 1400) 원전의 포괄부지 지반 중 B1,B4, C1 및 C3 지반을 대상으로 등재해도 스펙트럼을 도출하였다. 등재해도 스펙트럼을 통해 지진동 발생 빈도 별 위험 주파수 대역을평가하고 분석하였다. 이 결과는 원전의 종합적 지진리스크 평가 결과를 보다 합리적으로 개선하는 데에 활용될 수 있으며, 향후 다양한종류의 토사지반에 대한 등재해도 스펙트럼을 평가하는 데에 적용할 수 있을 것으로 기대된다.
It is a significant issue for several country including Korea, where the natural and the weather conditions are severe, to keep the safety against disasters which occur frequently every year, especially in urban region crowded with population. In order to implement suitable and effective measures against various disasters in such area, development of method for evaluation of disaster prevention performance based on various disaster risks and effective disaster damage mitigation technologies is independable. In this paper, methods for hazard evaluation, vulnerability evaluation and loss evaluation, and damage technologies are proposed targetting man-made disaster and natural one like flood, earthquake and tsunami and so on. The method proposed in this paper is based on the research of USA and Japan for man-made disaster and natural disaster. The proposed method will be developed in detail in four years during research period funded by government.
본 연구에서는 지진해일에 의한 원자력발전소의 확률론적 안전성 평가를 위하여 필수적으로 도출해야 하는 지진해일 재해도 곡선을 도출하기 위한 연구를 수행하였다. 1900년도 이후에 기록된 동해안에서의 지진해일 기록과 1900년도 이전에 역사지진기록에서 찾을 수 있는 지진해일 기록을 이용하여 지진해일에 의한 최대파고에 대한 재현주기를 산정하고자 하였다. Power law, upper-truncated power law 그리고 지수함수에 의해서 추세선을 작성하였으며 그 결과를 비교하였다. 동해안에서 발생한 지진해일의 기록이 10건 내외에 불과하므로 기록에 의한 지진해일 재해도 곡선추정 연구에 제한이 있으나 국내에는 지진해일의 재해도곡선 추정에 관한 연구가 전무한 현실이므로 지진해일 확률론적 안전성 평가를 위한 초석을 놓은 것으로 판단된다.
Since the school buildings are generally used as public shelters when the natural disasters such as flood and earthquake occur, it must be designed to show enough structural performance when subject to earthquake. Major failure mode of the school buildings observed in past earthquakes were shear failure of column of which length is shortened by infilled masonry blocks. ln this study, the seismic risk of the reinforced concrete school building structure was evaluated by using the seismic performance evaluation methods of low-story RC structures developed in Japan and the required seismic performance index which is obtained according to the KBC2008 seismic hazard map and soil types. ln this paper, the seismic performance of the school building is evaluated by considering this short-column effects, building shape and deterioration.
산림유역 조건에 따른 붕괴 토사량을 측정하여 사면 붕괴가능성을 평가하고 붕괴위험 지역에 대한 예지기술(豫知技術)을 개발함으로서 산지사면에서 발생하는 각종 재해에 대한 피해를 최소화 할 수 있는 산림유역 관리에 대한 기술적 기초 자료를 제공하고자 연구하였다. 붕괴 위험지역을 평가한 결과 I급지(매우 위험지역)는 화성암지 역으로 침엽수림이며 임령은 20년생 이하, 토심은 30cm 이하, 토성은 사질식양토(SCL), 석력함량은 31~40%, 사면방위는 남~동(S~E)사면, 주하천길이는 2,501~3,500m, 총하천수는26~30개, 총하천길이는5,501~10,000m, 하천차수는 3차수, 일차하천수는 11~15개 또는 16개 이상, 사면경사는 31˚이상의 지역으로 평가되었고, II급지(위험지역)는 변성암지역으로 활엽수림이며 임령은 21~24년생, 토심은31~40cm, 토성은 미사질식양토(SiCL) 또는 사질식양토(SCL), 석력함량은 11~20%, 사면방위는 남~서(S~W)사면, 주하천길이는 1,501~2,500m, 총하천수는 6~10개, 총하천길이는 3,501~5,500m, 하천차수는 2차수, 일차하천수는 6~10개, 사면경사는 31˚이상의 지역으로 평가되었으며, III급지(비 위험지역)는 퇴적암지역으로 임상은 혼효림, 임령은 25년생 이상, 토심은 41~50cm, 토성은 미사질식양토(SiCL), 석 력함량은 10% 이하, 사면방위는북~서(N~W)사면, 주하천길이는 500m 이하, 총하천수는 5개 이하, 총하천길이는 1,000m 이하, 하천차수는 1차수, 일차하천수는 2개 이하, 사면경사는 25˚이하의 지역으로 평가되었다. 붕괴위험 예측치를 이용하여 붕괴위험지역을 예지한 결과 점수의 합계가 I급지는 4.8052점 이상이며 II급지는 4.8051점에서 2.5602점 사이에 해당하며 III급지는 2.5601점 이하의 지역으로 분석되었다.
A local hazard mitigation plan (LHMP) or emergency plan is one of the most effective contributions for the mitigation of future local natural disasters. Since different regions are vulnerable to different natural disasters, each community should prepare their own plan based on their specific conditions. In Kumamoto, chronic flood damage and landslides are the most common hazards. In 2012, rapid heavy rain resulted in substantial property damage, casualties, and even fatalities. Studies indicate that Japanese communities have many volunteer groups to manage natural hazards and that their average risk reception is higher than in any other country. It can be said that Japanese government policy regarding natural disasters is good. However, it is time to reconsider our approach and reconfirm our fundamental commitment of designing an LHMP. This paper presents comparison research for Kumamoto hazard mitigation planning around 10- year time series, a longitudinal study. We used a flood mitigation plan coding protocol to better understand the Kumamoto City hazard mitigation plan. Indicators used in the study mostly focus on situations that the city has recently faced. Ultimately, the purpose of this research is twofold: 1) to assess the current mitigation efforts for a local flood event through a comparison study, and 2) to improve the LHMP more practically. To increase credibility and reliability, each researcher in this project checked the LHMPs three times. Eventually, through this study, it should be possible to enable the local government of Kumamoto to help establish a community resilient to its chronic natural disasters. Specific goals include determining which parts in the LHMP should be reinforced and whether improving the community resilience to flooding is possible
대구지역 대형식품접객업소 한식, 양식, 일식, 중식 각 3곳씩 12개 업소를 대상으로 조리기기 및 용기(칼, 도마, 행주, 집게, 바구니 등),조리종사자 손 및 조리 작업환경에 대한 미생물학적 위해를 분석하였다. 일부 한식당 조리수와 음용수의 일반세균 및 대장군균수가 범위로 검출되어 기준치에 부적합하였다. 특히 끓여서 식힌 보리차를 제공할 경우 음용수에 대한 미생물적 수치가 높은 것으로 나타났으며, 일부 양식당과 일식당의 음용수도 기준치에 부적합
본 연구에서는 국내에서 발생했던 산사태에 대한 사례연구를 통하여 GIS 기반의 산사태 예측모형 SINMAP의 적용성을 검토하였다. 사례연구의 대상지역은 서울에서 남쪽으로 78km 정도 떨어진 곳에 위치한 용인시 이동면 덕성리 소재 달봉산으로 1991년 집중호우기간 동안에 많은 산사태가 발생하였다. 이 지역에 대하여 SINMAP을 적용하여 당시 산사태지도와 비교 분석한 결과 대부분의 산사태를 성공적으로 예측하였다. 또한 본 연구에서는 SINMAP 모형의
우리나라에 주기적으로 내습하여 막대한 인명 및 재산피해를 발생시키고 있는 태풍의 재해위험도를 EST 기법을 적용하여 평가하였다. 서울을 비롯한 6개 주요 도시에 대하여 기존의 태풍자료를 Training Set으로 사용하여 In년 간의 태풍 모의 기간에 대하여 100회 반복모의를 수행한 결과로부터 재현기간별 최대풍속과 일최대강우량의 평균값, 표준편차, 최소값 및 최대값을 추정하였다. 재현기간 100년의 태풍에 대한 최대풍속의 평균값을 비교 평가한 결과 태