• Nuclear Engineering and Technology
• /
• 제49권8호
• /
• pp.1752-1757
• /
• 2017

The aim of this study is to evaluate the radioactivity levels and radiological impacts of representative black sand samples collected from different locations in the Rashid area, Egypt. These samples were prepared and then analyzed using the high-resolution gamma ray spectroscopy technique with a high-purity germanium detector. The activity concentration ($A_c$), minimum detectable activity, absorbed gamma dose rate, external hazard index ($H_{ex}$), annual effective dose rate equivalent, radium equivalent, as well as external and internal hazard index ($H_{ex}$ and $H_{in}$, respectively) were estimated based on the measured radionuclide concentration of the $^{238}U$($^{226}Ra$) and $^{232}Th$ decay chains and $^{40}K$. The activity concentrations of the $^{238}U$, $^{232}Th$ decay series and $^{40}K$ of these samples varied from $45.11{\pm}3.1Bq/kg$ to $252.38{\pm}34.3Bq/kg$, from $64.65{\pm}6.1Bq/kg$ to $579.84{\pm}53.1Bq/kg$, and from $403.36{\pm}20.8Bq/kg$ to $527.47{\pm}23.1Bq/kg$, respectively. The activity concentration of $^{232}Th$ in Sample 1 has the highest value compared to the other samples; this value is also higher than the worldwide mean range as reported by UNSCEAR 2000. The total absorbed gamma dose rate and the annual effective dose for these samples were found to vary from 81.19 nGy/h to 497.81 nGy/h and from $99.86{\mu}Sv/y$ to $612.31{\mu}Sv/y$, which are higher than the world average values of 59 nGy/h and $70{\mu}Sv/y$, respectively. The $H_{ex}$ values were also calculated to be 3.02, 0.47, 0.63, 0.87, 0.87, 0.51 and 0.91. It was found that the calculated value of $H_{ex}$ for Sample 1 is significantly higher than the international acceptable limit of <1. The results are tabulated, depicted, and discussed within national and international frameworks, levels, and approaches.

• 한국환경과학회지
• /
• 제19권6호
• /
• pp.747-753
• /
• 2010

It follows in quality and sewage exclusion method of the investigation objective sector and the Combined Sewer Overflows which is suitable in regional characteristics and the confluence area against the rainfall initially a flow and the medulla and measurement - it analyzes the initial rainfall outflow possibility control plan which is suitable in the domestic actual condition and it proposes the monitor ring plan for the long-term flow and pollution load data accumulation. From the research which it sees the Infiltration water/Influent water and CSOs investigation it passes by the phase of hazard chain and Namwon right time 4 it does not hold reverse under selecting, Measurement it used the hazard automatic flow joint seal Sigma 910 machine and in case 15 minute interval of the I/I, it measured a flow at case 5, 15 minute standing of the CSOs. The water quality investigation for the water leakage investigation of the I/I and the sewage from the point which is identical with flow measurement during on-the-spot inspection duration against 6 items which include the BOD sampling and an analysis, when the rainfall analysis for CSOs fundamental investigation analyzed against 18 items which include the BOD sampling. Consequently, for the optimum interpretation invasion water / inflow water of the this investigation area day average the lowest flow - water quality assessment veterinarian optimum interpretation hazard average per day - lowest flow - it averages a medulla evaluation law department one lowest flow evaluation technique and it selects, it presentation collectively from here it gets, position result with base flow analysis of invasion water / inflow water.

• Spatial Information Research
• /
• 제23권2호
• /
• pp.39-48
• /
• 2015

본 연구에서는 2차원 범람해석을 통해 도출된 침수해석정보에 현실적인 위험도를 고려한 산정식을 적용하여 홍수위험도를 평가하였고, 이를 표준화된 정보체계로 제공하는 방안을 제시하였다. 일반적으로 침수심과 침수구역을 기반으로 하는 현재의 홍수위험도 평가방법은 홍수발생시 사람에게 미치는 실질적인 위험도를 충분히 반영하지 못 할 것으로 판단되어 침수심, 유속, Debris Factor와 Flood Hazard Rating 관계식을 이용하여 외수범람이 사람에게 미치는 홍수위험도를 평가하고 4개로 등급화하였다. 이를 위해 2차원 외수범람해석 모형인 Flumen을 이용하여 대구의 금호강유역 대하여 500년 빈도 홍수로 인한 월류와 200년 빈도 홍수로 인한 파제 시나리오에 따라 외수범람을 모의하였다. 이러한 연구결과를 통해 외수범람시 침수가 예상되는 지역에 위치한 사람들에게 더 현실적인 위험도정보를 제공하고, 표준화된 정보체계 기반에서 위험도정보 제공이 가능해짐으로써 재해관련분야의 정보분석, 평가, 계획수립 등 다양한 분야에서 활용성을 증대시킬 수 있을 것으로 판단된다.

• 한국지진공학회논문집
• /
• 제21권1호
• /
• pp.1-9
• /
• 2017

The scale of disaster and damage witnessed in the 2004 Indian Ocean Tsunami and the 2011 Great East Japan Tsunami has motivated researchers in developing foolproof disaster mitigation techniques for safety of coastal communities. This study focuses on developing tsunami hazard map by numerical modeling at Imwon Port to minimize losses of human beings and property damage when a real tsunami event occurs. A hazard map is developed based on inundation maps obtained by numerical modeling of 3 past and 11 virtual tsunami cases. The linear shallow-water equations with manipulation of frequency dispersion and the non-linear shallow-water equations are employed to obtain inundation maps. The inundation map gives the maximum extent of expected flooded area and corresponding inundation depths which helps in identifying vulnerable areas for unexpected tsunami attacks. The information can be used for planning and developing safety zones and evacuation structures to minimize damage in case of real tsunami events.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 춘계 학술발표회
• /
• pp.444-455
• /
• 2009

Great concerns on geotechnical risk & hazard assessment have been increased due to human and economic damage by natural disasters with recent global climate changes. In this paper, geotechnical problems in particular, landslides which is interested in European countries and North America, were mainly discussed. For these, 18 key topics on geotechnical risk and hazards which had been discussed at the LARAM 2008 workshop in Italy were analyzed after grouping by subjects. Main topic contents consisted of applications such as field measurement, early warning systems, uncertainty analysis of parameters using radar, optical data and statistical theory and so on. And the problems related to analysis of vulnerability and deformation due to earthquakes, investigation of gas zone using seismic reflection data in a landslide area, risk quantification and hazard assessment of landslide movements and multi-dimensional analysis for stability of complex slopes were attracted. Also, there were studies on risk matters of cultural heritage, the blockglide of clayey ground, simulations of debris flows based on GIS, quantification of the failure processes of rock slopes, a meshless method for 3D crack modelling, and finally risk assessment for cryological processes due to global warming.

• 대한공간정보학회지
• /
• 제24권2호
• /
• pp.15-24
• /
• 2016

This study conducted an evaluation of the extent of debris flow damage using SINMAP, which is slope stability analysis software based on the infinite slope stability method, and FLO-2D, a hydraulic debris flow analysis program. Mt. Majeok located in Chuncheon city in the Gangwon province was selected as the study area to compare the study results with an actual 2011 case. The stability of the slope was evaluated using a DEM of $1{\times}1m$ resolution based on the LiDAR survey method, and the initiation points of the debris flow were estimated by analyzing the overlaps with the drainage network, based on watershed analysis. In addition, the study used measured data from the actual case in the simulation instead of existing empirical equations to obtain simulation results with high reliability. The simulation results for the impact of the debris flow showed a 2.2-29.6% difference from the measured data. The results suggest that the extent of damage can be effectively estimated if the parameter setting for the models and the debris flow initiation point estimation are based on measured data. It is expected that the evaluation method of this study can be used in the future as a useful hazard mapping technique among GIS-based risk mapping techniques.

• 국토계획
• /
• 제54권1호
• /
• pp.148-158
• /
• 2019

The purpose of this study is to analyze the impact of earthquake on apartment prices. Many studies have been done analyzing the relationship between natural hazards and residential property prices. Most studies have shown that natural hazards have an negative effect on residential property prices, but some studies have shown that natural hazards have an positive effect on residential property prices. These conflicting analysis result from the lack of considering natural hazard frequency at the analysis site. According to literature reviews risk avoidance tendency are already inherent in prices, thus distorting the relationship between natural hazards and prices. That is, in order to analyze the impact of natural hazards on residential property prices, analysis must be carried out in areas where there has not suffered natural hazard for a long time or where there has been no damage before. Nevertheless, previous studies analyzed areas frequently affected by natural hazards. Gyeongju has been recognized as a safe area from earthquake in the past, an 5.8 magnitude earthquake occurred in September 2016. Analysis results focusing on Gyeongju Earthquake case has shown that the earthquake has affected decrease of apartment prices in hazardous areas, and after earthquake apartment prices have risen over time.

• 한국지반공학회논문집
• /
• 제37권12호
• /
• pp.7-23
• /
• 2021

전력, 통신, 상수, 난방, 중수 등의 공급망을 구성하는 지하공동구는 도시기능을 유지하기 위한 핵심 기간망이며, 재난 및 재해로 서비스의 정지 및 일시적 중단이 발생하는 경우 대규모 사회경제적 손실을 가져온다. 본 연구에서는 지중구조물에 대한 개선된 내진설계 및 평가를 위하여 국내 지진환경에 부합하는 지진원 스펙트럼으로부터 대상 지반의 증폭 및 감쇠 효과를 반영한 시나리오 지진에 기반한 지반변위 예측 방법을 제시하였다. 코사인법으로 통용되는 기존의 단순화 가정법 및 지반응답해석과의 비교를 통해서 본 연구가 제시하는 재해도에 상응하는 지반변위 산정방법이 합리적이며 공학 실무에서 충분히 적용 가능한 것을 확인하였다.

• Nuclear Engineering and Technology
• /
• 제56권2호
• /
• pp.707-714
• /
• 2024

Different degrees of natural radioactivity found in quartz can have negative consequences on health. Quartz vein along the investigated Abu Ramad area, Egypt, had its natural radioactivity assessed. The HPGe spectrometer was used to determine the role played by the radionuclides ²³⁸U, ²³²Th, and ⁴⁰K in the gamma radiation that was emitted, and the results showed that these concentrations are 484.64 ± 288.4, 36.8 ± 13.1 and 772.2 ± 134.6 Bq kg^-1 were higher than the corresponding reported global limits of 33, 45, and 412 Bq kg^-1 for each radionuclide (²³⁸U, ²³²Th, and ⁴⁰K). Among the radiological hazard parameters, the excess lifetime cancer risk (ELCR) is estimated and it's mean value of ELCR (1.2) is higher than the permissible limit of 0.00029. The relationship between the radionuclides and the associated radiological hazard characteristics was investigated based on multivariate statistical methods including Pearson correlation, principal component analysis (PCA), and hierarchical cluster analysis (HCA). According to statistical research, the radioactive risk of quartz is primarily caused by the ²³⁸U, ²³²Thand ⁴⁰K. Finally, applying quartz to building materials would pose a significant risk to the public.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
• /
• pp.721-724
• /
• 2006

Among many sources of soil and water pollution, former mining regions also play an important role in distribution and scope of pollution. In response, KMRC has made an investigation into the status mine hazard at the abandoned metalliferous mine area in Korea. In this study, we analyzed distribution of mine hazards at abandoned metalliferous mines using GIS. We considered the distribution of mine hazards and its magnitude for each abandoned mine and displayed the mine hazard index (MHI) using GIS. We divided the MHI value for each mine into 5 classes, and displayed the first class as smallest point symbol and the last class as biggest point symbol. The biggest symbol shows the most serious status of mine hazards. This GIS function was included in the AMGIS system KMRS are running, and it would be helpful to make decision of reclamation priority at abandoned metalliferous mine area.