In recent years, deaths and missing people have continuously occurred due to man overboard (MOB) and suicide on passenger ships. However, due to the complex deck structure and enlargement of passenger ships, closed-circuit television (CCTV) coverage is limited, and it is difficult to prevent accidents for all passengers with limited crews. Therefore, a real-time system for detecting high-risk blind spots on passenger ships is needed through risk analysis. This study used a combination of the following three risk factors to calculate and evaluate the risk of MOB and suicide by deck area of the passenger ship: 1) distance away from guard rails, 2) the visibility of CCTV, and 3) ship operating conditions. Based on the survey from experts, risk scores of MOB and suicide accidents by deck area on a passenger ship were yielded.

of hazardous risk factors, risk estimation and determination steps by reflecting the trend of overseas risk assessment. METHODS : In deriving, estimating and determining risk factors, comparing the procedures presented by the ILO with the domestic guidline to find out the differences in procedural. and, According to the domestic manual, after setting the criteria for determining a deterministic perspective, analyze the risk assessment data of a specific domestic company and three overseas risk assessment research data to analyze the differences in methodology domestic and abroad. RESULTS : Within the country, there is a possibility that a deterministic view may be applied to all stages of procedure, and certain corporate data to the risk estimation and determination stage. In the case of overseas, the trend of applying deterministic perspectives to the risk determination stage was confirmed. CONCLUSIONS : Present the need for a standard model for improving deterministic methods in the other two stages, excluding risk determination in the domestic evaluation procedure.

Herbicide-resistant transgenic rapeseed (TG rapeseed) was developed by inserting phosphinothricin acetyltransferase (PAT, bar), a modified gene from the soil bacterium Streptomyces hygroscopicus, into the genome of a conventional variety of rapeseed (Youngsan). The TG rapeseed used for the test was confirmed to express the PAT gene by polymerase chain reaction (PCR) and immunostrip. Feeding tests were conducted with Cyprinus carpio to evaluate the environmental risk of TG rapeseed, including the herbicide resistant gene. C. carpio was fed 100% ground rape suspension, TG rapeseed, or non-genetically modified (GM) counterpart rapeseed (Youngsan). As a result, the feeding test showed no significant differences in the cumulative immobility or abnormal response between C. carpio samples fed on TG rapeseed and non-GM counterpart rapeseed. The 48 h-LC50 values of the TG rapeseed and the non-GM counterpart rapeseed were 3,376 mg/L (95 % confidence limits: 3,169 - 3,596 mg/L) and 2,682 mg/L (95 % confidence limits: 2,267 – 3,123 mg/L), respectively. The rape NOEC (no observed effect concentration) value for C. carpio was suggested to be 625 mg/L. Based on these results, there was no significant difference in the toxicity for non-target organisms (C. carpio) between the TG rapeseed and non- GM counterparts.

The demand for transportation is increasing due to the continuous generation of radioactive wastes. Especially, considering the geographical characteristics of Korea and the location characteristics of nuclear facilities, the demand for maritime transportation is expected to increase. If a sinking accident happens during maritime transportation, radioactive materials can be released into the ocean from radioactive waste transportation containers. Radioactive materials can spread through the ocean currents and have radiological effects on humans. The effect on humans is proportional to the concentration of radioactive materials in the ocean compartment. In order to calculate the concentration of radioactive materials that constantly flow along the ocean current, it is necessary to divide the wide ocean into appropriate compartments and express the transfer processes of radioactive materials between the compartments. Accordingly, this study analyzed various ocean transfer evaluation methodologies of overseas maritime transportation risk codes. MARINRAD, POSEIDON, and LAMER codes were selected to analyze the maritime transfer evaluation methodology. MARINRAD divided the ocean into two types of compartments that water and sediment compartments. And it was assumed that radionuclides are transfered from water to water or from water to sediment. Advection, diffusion, and sedimentation were established as transfer process for radionuclides between compartments. MARINRAD use transfer parameters to evaluate transer processes by advection, diffusion, and sedimentation. Transfer parameters were affected by flow rate, sedimentation rate, sediment porosity, and etc. POSEIDON also divided the ocean into two types that water and sediment compartment, each compartments was detaily divided into three vertical sub-compartment. Advection, diffusion, resuspension, sedimentation, and bioturbation were established as transport processes for radionuclides between compartments. POSEIDON also used transfer parameters for evaluating advection, diffusion, resuspension, sedimentation, and bioturbation. Transfer parameters were affected by suspended sediment rates, sedimentation rates, vertical diffusion coefficients, bioturbation factors, porosity, and etc. LAMER only considered the water compartment. It divided the water compartment into vertical detailed compartments. Diffusion, advection and sedimentation were established as the nuclide transfer processes between the compartments. To evaluated the transfer processes of nuclides for diffusion and advection, LAMER calculated the probability with generating random position vectors for radionuclides’ locations rather than deterministic methods such as MARINRAD’s transfer parameters or POSEIDON’s transfer rates to evaluate transfer processes. The results of this study can be used as a basis for developing radioactive materials’ ocean transfer evaluation model.

At the end of 2022 there were 439 nuclear power reactors in operating around the world, including 25 nuclear power reactors of Korea. Domestic nuclear power plants (NPPs) continuously produce low and intermediate-level radioactive waste (LILW) and spent nuclear fuel (SNF). As amount of radioactive waste is increasing and interim storage facilities meet limitation of their capacity, radioactive waste need to be transported. Consequently, the demand for radioactive waste transportation is increasing and the importance of Radiation Risk Assessment Codes (RRACs) for radioactive waste transportation is also on the rise. Considering the domestic situation where all NPPs are located on seaside, the radioactive waste transportation by ship is inevitable and the its risk assessment is very important for safety. Although various researches on radioactive waste transportation risk assessment is being actively conducted, research on domestic radioactive waste maritime transportation is insufficient. In this study, MARINRAD and KM-RAD were used to review on the radioactive waste transportation risk assessment. The result of reviewing shows that MARINRAD used SNF as transporting radioactive materials and ‘SAND87-7067 (1987)’ as nuclide database, whereas KMRAD used LILW and ‘IAEA Technical Report Series-422 (2004)’. To complement these limitations, we present an modernized integrated database by updating data and covering the radioactive materials from LILW to SNF. These results are expected to contribute to the development of RRACs for domestic radioactive waste maritime transportation.

In Korea, Kori Unit 1 and Wolsong Unit 1, have been permanently shut down in 2017 and 2019, and more nuclear power plants are expected to be permanently shut down after continued operation successively. Spent fuel has been generated during operation and stored in spent fuel pools. Due to the expected saturation of spent fuel pools within the next several decades, transportation of a huge amount of spent fuel is anticipated to interim storage facilities or final disposal facilities, even though the specific location is not decided. The U.S. Nuclear Regulatory Commission (NRC) states that every environmental report prepared for the licensing stage of a Pressurized Water Reactor shall contain a statement concerning risk during the transportation of fuel and radioactive wastes to and from the reactor. Thus, the licensee should ensure that the radiological effects in accidents, as well as normal conditions in transport, do not exceed certain criteria or be small if cannot be numerically quantified. Specific conditions that a full description and detailed analysis of the environmental effects of transportation of fuel and wastes to and from the reactor are exempted are specified in 10 CFR Part 51. Since there are no official requirements for radiological dose assessment for workers and public during the transportation of spent fuel in Korea, the margin when applying the U.S. regulatory criteria to the environmental impact assessment during the transport of spent fuel generated from domestic nuclear power plants is evaluated. A different approach would be needed due to the difference in the characteristics of spent fuel and geographical features.

This study proposes a methodology for the regional seismic risk assessment of structural damage to buildings in Korea based on evaluating individual buildings, considering inconsistency between the administrative district border and grid lines to define seismic hazard. The accuracy of seismic hazards was enhanced by subdividing the current 2km-sized grids into ones with a smaller size. Considering the enhancement of the Korean seismic design code in 2005, existing seismic fragility functions for seismically designed buildings are revised by modifying the capacity spectrum according to the changes in seismic design load. A seismic risk index in building damage is defined using the total damaged floor area considering building size differences. The proposed seismic risk index was calculated for buildings in 29 administrative districts in 'A' city in Korea to validate the proposed assessment algorithm and risk index. In the validation procedure, sensitivity analysis was performed on the grid size, quantitative building damage measure, and seismic fragility function update.

For safe and economical spent fuel management, assessing the integrity of the cladding, which is the first barrier to the escape of radioactive material, is very important. For the sake of risk assessment, it is essential to calculate the probability of failure of the spent fuel rods loaded inside the cask during the transportation or storage. However, due to the large amounts of calculations required, it is not practical to analyze every detail of the spent fuel rods and assemblies. This study presents a methodology to perform a cask-level analysis by sequentially simplifying the fuel rods and spent fuel assemblies for the calculation of fuel rod failure probability. A simplified single fuel rod model was generated by considering the material properties of a high burnup fuel rod stored in dry storage for approximately 5 years and the interfacial bonding conditions of the cladding tube. The simplified model produces the same deflection as the detailed model at the critical moment that produces a fracture plastic strain of 1%. The developed single fuel rod simplified model is assembled in a CE 16×16 configuration, and a methodology is presented in which the CE 16×16 assembly model is once again replaced by a simplified model with a cuboidal shape. Compression analyses were performed on each part of the CE 16×16 model to obtain isotropic property data, and a simplified model was created based on those data and the cross-sectional second moment values of the parts. A cask drop analysis was performed to validate the similarity of the CE 16×16 model and the simplified model by comparing important structural responses such as impact acceleration. The 20 simplified fuel assembly models and one detailed model were loaded into a cask to perform the drop analysis. For the detailed model, the impact acceleration was extracted for different loading positions and the corresponding impact load and pinch load were derived. The spring force and contact force corresponding to the pinch load were extracted by applying a Python script technique to extract the maximum value of them exerted on each fuel rod. The vulnerability of spent fuel rods to bending loads and the failure criteria were considered during the simplification process of a single fuel rod. From the extracted impact and pinch loads, the probability of failure of the spent fuel rods as a function of impact acceleration can be calculated.

In this study, in order to establish a strategy for developing an fire following earthquake risk assessment method that can utilize domestic public databases(building datas, etc.), the method of calculating the ignition and fire-spread among the fire following earthquake risk assessment methodologies proposed by past researchers is investigated After investigating and analyzing the methodology used in the HAZUS-MH earthquake model in the United States and the fire following earthquake risk assessment methodology in Japan, based on this, a database such as a domestic building data utilized to an fire following earthquake risk assessment method suitable for domestic circumstances (planned) was suggested.

Compared to operational wastes, nuclear power plant (NPP) decommissioning wastes are generated in larger quantities within a short time and include diverse types with a wider range of radiation characteristics. Currently used 200 L drums and IP-2 type transport containers are inefficient and restrictive in packaging and transporting decommissioning wastes. Therefore, new packaging and transport containers with greater size, loading weight, and shielding performance have been developed. When transporting radioactive materials, radiological safety should be assessed by reflecting parameters such as the type and quantity of the package, transport route, and transport environment. Thus far, safety evaluations of radioactive waste transport have mainly targeted operational wastes, that have less radioactivity and a smaller amount per transport than decommissioning wastes. Therefore, in this study, the possible radiation effects during the transport from NPP to disposal facilities were evaluated to reflect the characteristics of the newly developed containers and decommissioning wastes. According to the evaluation results, the exposure dose to transport workers, handling workers, and the public was lower than the domestic regulatory limit. In addition, all exposure dose results were confirmed, through sensitivity analysis, to satisfy the evaluation criteria even under circumstances when radioactive materials were released 100% from the container.

본 연구에서는 울산지역에서 유통되는 로컬푸드 농산물 367건에 대해 다성분 분석법을 이용하여 잔류농약 350종 을 분석한 결과 다음과 같다. 로컬푸드 농산물에 대한 잔류농약 분석 결과 21.5%(79 건)의 검출률을 보였으며 부적합률은 1.1%(4건)으로 나타 났다. 품목별로 과일류는 65건 중 27건(41.5%), 채소류는 242건 중 50건(20.7%), 두류는 7건 중 1건(14.3%), 곡류 11건 중 1건(9.1%) 검출률을 보였고, 취나물, 곤달비, 파, 살구에서 기준치 이상의 잔류농약이 검출되었다. 검출된 잔류농약은 총 58종 163회로 살충제 성분이 가 장 많이 검출되었고 고독성 농약 1회, 보통 독성 농약 9 회, 저독성 농약이 48종이었다. 부적합 처리된 품목을 포함한 검출된 잔류농약 항목에 대한 위해도 평가 결과 위해지수(%ADI) 가 0.0000- 63.1043% 으로 모두 100% 미만으로 위해하지 않은 수준 으로 판단되었다. 지속적으로 로컬푸드 농산물의 운동 추진 방향인 지역 활성화와 안전한 먹거리 공급체계구축의 목적을 위해 엄 격히 관리되는 기준으로 안전성 검사를 실시하고, 신뢰성 확보를 위한 생산자 교육 및 홍보, 출하 전 안전성 검사 관리시스템이 정착된다면 울산지역 로컬푸드 농산물 사업 이 더욱 활성화되고 지속적으로 추진 될 수 있을 것으로 판단된다.

미세플라스틱 입자는 환경 내 어디에나 존재하며 크기, 모양 또는 유형의 표준화된 입자가 아 니다. 따라서 독성자료를 바탕으로 해수, 퇴적물 등 해양환경의 다차원을 정확하게 평가하고 관리하는 위험평가 프레임워크를 구축하는 것은 매우 어렵다. 본 연구에서는 해양환경 미세플 라스틱의 특징과 영향을 조사하였고, 해양환경 미세플라스틱의 분포와 생물영향에 따른 위해 도 평가 프레임워크(초안)를 제안하고 있다. 환경 미세플라스틱의 특성은 매우 다양하지만 대 부분의 독성 데이터는 독특한 형태와 유형에 집중되어 있으며, 실험실 노출 생물과 관리해야 하는 생물 종도 다르다. 실제적으로, 지금까지의 수집된 연구결과는 위해성평가에 활용하기에 독성 데이터 품질에 있어 불확실성이 높기도 하며, 전통적인 위해성평가 프레임워크를 적용 하는 데 있어 고려할 부분이 많이 존재한다. 그러나, 현재 미세플라스틱 관리에 대한 국제사회 의 움직임이 점차 강화되고 있고, 해양환경의 미세플라스틱 오염도가 높아지고 있는 점을 고 려하면, 해양환경의 미세 플라스틱 특성에 기초한 위해성평가 기법 구축에 대한 추가 연구가 제안되어야 할 것이다.

For licensees who face the decommissioning project for the first time, even if they can utilize their experience in operation, they should be well prepared and assessed for the risks of dismantling activities reflecting the characteristics of decommissioning. This can be included in the risk management of the decommissioning project, but what we want to discuss in this study is the evaluation of the industrial risk of the actual work before the dismantling work is carried out. We would like to focus more on the review of dismantling activities subject to industrial risk assessment and a series of processes for risk assessment. The dismantling work plan will need to obtain approval from the supervisory department before work on the Systems, Structures, and Components (SSCs) can be carried out. At this time, risk assessment may be included among many safety-related required documents, which are divided into radiological and non-radiological risks. The target activities at Level 1 level can include preparation for dismantling and maintenance of facilities, dismantling big components, removing the contamination of concrete structures, managing radioactive waste, etc. In addition, it can be composed of preparation work, removal of connections, lifting/installation, cutting, radiation/radioactivity measurement, and withdrawal as detailed work stages of each item’s activities. For domestic nuclear decommissioning projects, two major performance organizations, licensees and contractors, must be considered. Regarding risk assessment, the licensee will have a supervisory department controlling decommissioning activities and an HSE department at the site, and a process will need to be established in consideration of the contractor’s work organization. Therefore, activities in the risk assessment process may be established. In this study, risk assessment was reviewed as safety-related matters to be considered when carrying out the dismantling work. Safety-related risk assessment is a necessary procedure for performing practical dismantling activities, and this should be considered well in advance. Therefore, work activities and criteria were established for risk assessment, and the performance process was assumed to apply them. In terms of the performance organization and the responsibilities and roles of the processes to be performed by each organization were constructed, and this can be referred to in the process of preparing for the decommissioning project.

This study aims to present a method to evaluate the relative risk of failure due to liquefaction of domestic small to medium-sized earthfill dams with a height of less than 15 m, which has little information on geotechnical properties. Based on the results of previous researches, a series of methods and procedures for estimating the probability of dam failure due to liquefaction, which calculates the probability of liquefaction occurrence of the dam body, the amount of settlement at the dam crest according to the estimation of the residual strength of the dam after liquefaction, the overtopping depth determined from the amount of settlement at the dam crest, and the probability of failure of the dam due to overtopping was explicitly presented. To this end, representative properties essential for estimating the probability of failure due to the liquefaction of small to medium-sized earthfill dams were presented. Since it is almost impossible to directly determine these representative properties for each of the target dams because it is almost impossible to obtain geotechnical property information, they were estimated and determined from the results of field and laboratory tests conducted on existing small to medium-sized earthfill dams in previous researches. The method and procedure presented in this study were applied to 12 earthfill dams on a trial basis, and the liquefaction failure probability was calculated. The analysis of the calculation results confirmed that the representative properties were reasonable and that the overall evaluation procedure and method were effective.

선박 연료로서 LPG는 현재의 기술과 경제성 등을 고려하였을 때 매력적인 연료이다. 하지만, 아직 LPG 연료 선박의 안전 지침 을 개발 중에 있고, 국내에서는 중소형 선박에 LPG 추진 시스템을 적용한 사례가 없다. 본 연구에서는 국내 최초 개발된 해상용 LPG 엔 진 시스템에 대해 보다 객관적인 위험성 평가를 수행하고 안전 운용 기준을 제안하고자 한다. 우선, 위험과 운전 분석 기법을 통해 동 엔 진 시스템을 5개의 검토 구간으로 분할하고 총 58가지의 위험요소를 식별하였다. 그다음 정성적 평가인 HAZOP 기법의 주관성을 보완하 기 위해 퍼지 이론을 사용하고 검출도, 민감도 등 위험 요인을 추가하여 퍼지 분석적 계층 과정을 통해 위험 요인의 상대적 가중치를 비 교하였다. 그 결과, 5가지의 위험 요인 중, 위험성에 가장 큰 영향을 미치는 위험 요인은 발생 빈도와 심각도로 평가되었다. 마지막으로, 위험 요인에 대한 가중치를 고려하여 위험 순위를 세밀하게 선정하기 위해 퍼지 TOPSIS 기법을 적용하였다. 그 결과, 위험 등급은 47개 그룹으로 구분할 수 있었고, 동 엔진 시스템의 운용 중 가장 위험도가 높은 위험요소는 LPG 공급 라인 유지 보수 중 가스 누출로 분석되 었다. 본 연구에 제안된 기법을 LPG 공급계통 등 다양한 설비에도 적용하여, 향후 LPG 추진 선박의 안전 기준 마련을 위한 위험성 평가 의 표준절차로 활용할 수 있기를 기대한다.