When decommissioning a nuclear power plant, it is expected that clearance or radioactive waste (e.g., soil, concrete, metal, etc.) below the low-level will be generated in a short period on a large scale. Among the various types of waste, most of the contaminated soil is known to be classified as clearance or the (very) low-level radioactive waste. Accordingly, an accurate measurement and classification of contaminated soil in real-time during the decommissioning process can efficiently reduce the amount of soil waste and the possibility of contamination diffusion. However, in order to apply a system that measures and classifies contaminated soil in real-time according to the level of contamination to the decommissioning site, a demonstration is required to evaluate whether the system is applicable to the site. In this study, to establish requirements for determining the applicability of the system to the decommissioning site, preceding cases from countries with abundant decommissioning experience were investigated. For example, MACTEC of the U.S. demonstrated the developed system at the Saxton nuclear power plant in the U.S. and confirmed that the amount of soil that can be analyzed per hour in the system is affected by radionuclides, minimum detectable activity (MDA), and applicable volume. In the future, therefore, we will utilize the result of this study to develop the requirements of demonstrating the system for measurement and classification of contaminated soil in real-time.

For safe and successful decommissioning, it is one of the most important procedures that establishing the goal and complying with regulations of which final status of decommissioned site and building. The dose criteria for cyclotron facilities should be established and applied to reuse the site and building, since building and component of a cyclotron facility have been activated by incident secondary neutrons from radioactive isotope processes (e.g. 18O(p,n)18F, etc.). Furthermore, appropriate approaches should be applied to demonstrate compliance with the dose criteria for reliability of reuse. It is of noted that U.S. NRC (Nuclear Regulatory Commission) has confirmed that the residual radioactivity which distinguishable from background radiation results in a TEDE (Total Effective Dose Equivalent) does not exceed 25 mrem (0.25 mSv) per year as radiological criteria for unrestricted use of not only nuclear power plants but also cyclotron facilities referred to 10 CFR Part 20.1402. In addition, U.S. NRC noted the two approaches (i.e. dose assessment methods and, DCGL and final status surveys) which can be applied for demonstrating compliance with the dose criteria of 10 CFR Part 20 and recommended DCGL and FSS approach based on advantages and disadvantages of the two approaches. In order to using DCGL and FSS approach, U.S. NRC suggested screening approach; using DandD Version 2 which assesses TEDE under ICRP 28 and site-specific approach; using all models or computational codes which approved by NRC staff. There are several foreign cases that release of cyclotron facilities after decommissioning (i.e. U.S. and Japan). U.S., for examples, there are two DCGL approach cases and one dose modeling case based on 25 mrem per year same as reactor facilities. The dose modeling case, however, which may not be really used in Korea because of its low applicability. On the other hand, Japan case did not establish any radiological criteria for site and building reuse such as DCGL and just confirm “no more contamination” which is all residual radioactivity is lower than MDC based on real survey. Japan case also may not be used in Korea since criteria of “no more contamination” is not clear and hard to apply for all sites. Considering regulations and criteria for site release and reuse in Korea, this study aims to suggest radiological criteria and the demonstration approach of compliance for decommissioning of cyclotron facilities based on Nuclear Safety Acts and NSSC notices.

For the disposal of radioactive waste from nuclear facilities, assessing their radioactivity inventories is essential. As a result, countries with nuclear facilities are implementing assessment schemes tailored to their respective policies and available resources for radioactive waste management. This paper specifically describes the assessment scheme for radioactivity inventory applied to metal waste generated during the dismantling of the Japan Power Demonstration Reactor (JPDR), a 1.25 MW BWR. The distinctive aspect of the Japanese approach lies in the fact that, for a pair of a key nuclide and a difficult-to-measure (DTM) nuclide that lack a significant correlation in their concentrations, the mean activity concentration method was used. In this method, an arithmetic average of all measurements of the DTM nuclide from representative drums, including MDAs (Minimum Detectable Activities), was assigned to the concentration of the DTM nuclide for all drums, regardless of the concentration of its paired key nuclide. Conversely, for a specific pair of a key nuclide and a DTM nuclide with a significant correlation, the scaling factor method was applied, as is common in many other countries. This Japanese case can serve as a valuable reference for Korea, which does not have the option of using the mean activity concentration method in its assessment scheme.

The decommissioning of Korea Research Reactor Units 1 and 2 (KRR 1&2), the first research reactors in South Korea, began in 1997 and the decommissioning status is currently proceeding with phase 3. It is expected that more than 5,000 tons of dismantled wastes will be generated as the contaminated building is demolished. Since these dismantled wastes must be disposed of in an efficient method considering economic feasibility, it is desirable to clearance extremely low-level wastes whose contamination is so minimal that the radiological risk is negligible. In Korea, in order to approve the clearance of radioactive waste, it must be proven that the nuclide concentration standards are met or that the dose to individuals and collectives is below the allowable dose value. At the KRR 1&2 decommissioning site, dismantled wastes have been steadily being disposed of through clearance procedure since 2021. Clearance was approved by the Korean Institute of Nuclear Safety (KINS) for one case of concrete waste in 2021 and two cases of metal waste in 2022. In 2023, the clearance of metal waste and asbestos waste has been approved so far, and in particular, this is the first case in Korea for asbestos waste. In this study, we compared the dose assessment methods and results of clearance wastes at the KRR 1&2 decommissioning site from 2021 to present. Dose assessment was conducted by applying the landfill scenario for concrete and asbestos and the recycling scenario for metal waste. The calculation codes used were RESRAD-onsite 7.2 and RESRAD-recycle 3.10. The dose conversion factors (DCF) for each age group (infant, 1y, 5y, 10y, 15y, adult) of the target nuclide used the values presented in ICRP-72, and in particular, geo-hydrological data of the actual landfill site was used as an input factor when evaluating landfill scenarios. As a result of the dose assessment, when landfilling concrete wastes in 2020, the personal dose and collective dose were evaluated the most at 2.80E+00 μSv/y and 4.83E-02 man·Sv/y, respectively.

Advanced countries in the field of nuclear research and technology are currently examining the feasibility of deep geological disposal as the most appropriate method for the permanent management of high-level radioactive waste, with no intention of future retrieval. Deep geological disposal involves the placement of such waste deep underground within a stable geological formation, ensuring its permanent isolation from the human environment. To guarantee the enduring isolation and retardation of radionuclides with half-lives spanning tens of thousands to millions of years from the broader ecosystem, it is imperative to comprehend the long-term evolution of deep disposal systems, especially the role of natural barriers. These natural barriers, typically consisting of bedrock, encase the repository and undergo long-term evolutions due to tectonic movements and climate variations. For the effective disposal of high-level radioactive waste, a thorough assessment of the site’s long-term geological stability is essential. This necessitates a comprehensive understanding of its tectonic evolution and development characteristics, including susceptibility to seismic and magmatic events like earthquakes and intrusions. Furthermore, a detailed analysis of alterations in the hydrogeological and geochemical environment resulting from tectonic movements over extended time frames is required to assess the potential for the migration of radionuclides. In this paper, we have examined international evaluation methodologies employed to elucidate the predictive long-term evolution of natural barriers within disposal systems. We have extracted relevant methods from international case studies and applied a preliminary scenario illustrating the long-term evolution of the geological environment at the KURT (KAERI Underground Research Tunnel) site. Nevertheless, unlike international instances, the scarcity of quantitative data limits the depth of our interpretation. To present a dependable scenario in the future, it is imperative to develop predictive technologies aimed at comprehensively studying the geological evolution processes in the Korean peninsula, particularly within the context of radioactive waste disposal.

In 2012, POSIVA selected a bentonite-based (montmorillonite) block/pellet as the backfilling solution for the deposition tunnel in the application for a construction license for the deep geological repository of high-level radioactive waste in Finland. However, in the license application (i.e. SC-OLA) for the operation submitted to the Finnish Government in 2021, the design for backfilling was changed to a granular mixture consisting of bentonite (smectite) pellets crushed to various sizes, based on NAGRA’s buffer solution. In this study, as part of the preliminary design of the deep geological repository system in Korea, we reviewed history and its rationale for the design change of Finland’s deposition tunnel backfilling solution. After the construction license was granted by the Finnish Government in 2015, POSIVA conducted various lab- and full-scale in-situ tests to evaluate the producibility and performance of two design alternatives (i.e. block/pellet type and granular type) for backfilling. Principal demonstration tests and their results are summarized as follows: (a) Manufacturing of blocks using three types of materials (Friedland, IBeco RWC, and MX-80): Cracking and jointing under higher pressing loads were found. Despite adjusting the pressing process, similar phenomena were observed. (b) 1:6 scale experiment: Confirmation of density difference inhomogeneity due to the swelling of block/pellet backfill and void filling due to swelling behavior into the mass loss area of block/pellet. (c) FISST (Full-Scale In situ system Test): Identification of technical unfeasibility due to the inefficient (too manual) installation process of blocks/pellets and development of an efficient granular in-situ backfilling solution to resolve the disadvantage. (d) LUCOEX-FE (Large Underground Concept Experiments – Full-scale Emplacement) experiment: Confirmation of dense/homogeneous constructability and performance of granular backfilling solution. In conclusion, the simplified granular backfill system is more feasible compared to the block/ pellet system from the perspective of handling, production, installation, performance, and quality control. It is presumed that various experimental and engineering researches should be preceded reflecting specific disposal conditions even though these results are expected to be applied as key data and/or insights for selecting the backfilling solution in the domestic deep geological repository.

Deep borehole drilling is essential not only to select the host rock type for deep geological disposal of high-level radioactive waste (HLW), but also to identify the characteristics of the disposal site during the site selection process. In particular, since the disposal depth of HLW is considered to be over 300 m, deep borehole drilling must be performed. In deep borehole drilling, drilling design, excavation, and operation may vary depending on the rock type, drilling depth, and drilling purpose etc. This study introduced cases in which Korea was divided into four geotectonic structures and four representative rock types and conducted with a goal of 750 m drilling depth. Prior to this, a review of deep drilling cases conducted at domestic and abroad was presented. If sufficient time and cost are available, several drilling holes can be excavated for various purposes, but if not, one or two drilling holes should be used to achieve the objectives of various fields related to HLW disposal. The presence of bedding, strata or fault zones depending on the type of rock, etc. may affect drilling deviation or circulating water management. In addition, unlike drilling in general geotechnical investigation drilling, the use of polymers or grouting agents is limited to determine hydraulic and geochemical characteristics. This report introduces the experience considered during the design and drilling process of deep drilling in granite, gneiss, sedimentary rock, volcanic rock, etc., and is expected to be used as basic data when carrying out future HLW projects.

To ensure the long-term supply and sustainability of uranium fuel, exploring alternative resources is essential, particularly considering that terrestrial reserves of uranium are limited (about 4.6 million tons). Since the amount of uranium dissolved in seawater is approximately 1000 times that of terrestrial reserves (i.e., about 4.5 billion tons), uranium extraction from seawater (UES) can be an alternative resource. However, the ultra-low concentration of uranium in seawater (about 3.3 ppb) poses a significant challenge in achieving economic feasibility for UES. This paper introduces case studies on the cost analysis of systems for recovering uranium from seawater, specifically focusing on braided fiber-based adsorbents developed by JAEA and ORNL. The cost analysis has been conducted based on using the deployment of these adsorbents on the bottom of the sea, which is a passive deployment method, thereby reducing the total costs of recovery. The analysis results can be used to identify R&D areas necessary for reducing cost components, making UES economically feasible.

Strategic item export control aims to maintain international peace and safety and serves as a significant nuclear non-proliferation regime that directly impacts a nation’s security. Therefore, establishing an autonomous export control system at the state level is crucial, and one of the most efficient methods to achieve this is by enhancing an export company’s management system. Accordingly, many advanced countries, such as the United States, Europe, and Japan, have operated their own internal compliance programs (CP or ICP) to manage and screen the export of strategic items as a corporate social responsibility and risk mitigation measure. In Korea, which has a high dependence on trade, the need for CP was continuously confirmed, but the system was introduced in 2004, relatively late compared to other advanced countries. So far, the Korean government has made steady efforts to develop and establish the system and is actively encouraging businesses to obtain Compliance Program certification to autonomously manage strategic items. Major technologically advanced countries utilize technology transfer as a tool for economic sanctions, trade security, and strategic technology management, and they continue to strengthen their control regimes. In these countries, CP certification is considered a standard practice for export control among mid-sized and large enterprises. It serves as a vital risk management system that protects companies from unforeseen incidents. However, in Korea, the application of CP under the Foreign Trade Act is limited to dual-use items and does not extend to the nuclear export control system. Therefore, this paper analyzes international cases and CP requirements in countries like the United States, Japan, Europe, and Singapore. As a result of the review, the application of CP into Korea’s nuclear export control could be a coexistence means that can strengthen supply chain control as well as provide benefits not to impede technical research, international trade, and exchanges.

In recent times, drone technology has been rapidly advancing and becoming increasingly popular. Furthermore, there has been an increase in the number of crimes and terrorism cases targeting national facilities using drones. This study aims to categorize the types of drone threats that could pose future risks to nuclear power plants. For this study, we are investigating domestic and foreign drone terrorism cases and identifying the specifications of drones used. It has been confirmed that products from Chinese DJI companies have frequently appeared as commercial drones used in terrorism. This suggests that conversion of general commercial drones into weapons can be effectively utilized for terrorist activities. There is an elevated risk of terrorism involving multiple small drones. Nuclear power plants must also devise protective measures against a large influx of drones. Additionally, it is predicted that North Korea is developing drones equipped with return technology through GPS-based autonomous mission flights. North Korea’s drones are presumed to have been converted from Chinese drones (SKY-09P, UV10CAM, etc.). According to the analysis based on the weight and size of the drone, drones weighting less than 150 kg and wingspan of less than 3 m are used for terrorism. To effectively detect drones, it is necessary to implement measures such as integrating and deploying various equipment to compensate for equipment limitations (radio waves, radar, video, sound, etc.). In the case of long-distance flight, a number of fixed-wing drones capable of autonomous mission flight and long-distance flight were used. North Korea’s drones use GPS-based autonomous mission flights, so it is necessary to prepare drones that do not transmit RF signals to detect them. Both RF signal detection and GPS jamming should be carried out, with GPS jamming taking precedence, even in the case of fixedwing drones. The results of this study could contribute to enhancing the level of physical protection of nuclear power plants.

본 연구는 관형격 명사구 구성 ‘명사+ 의+ 명사’에서 선행 성분과 후 행 성분을 연결을 시키는 ‘의’는 단순한 수의적 실현 경우에서 특히 통사 적 실현 가능성에 대한 논의를 하고자 하는 목적이 있다. 특히 수의적 경우에서 나타난 ‘의’ 생략 실현 양상을 검토하고자 할 것이다. 본 연구 는 먼저 기저 구조에 들어가 문장에서 서술어와 논항을 연결하는 관계 즉, 연합성 관계를 통해, ‘의’가 속한 관형격 명사구가 서술어와의 연합 성 정도에 따라서 1차 서술어적 관형격 명사구와 2차 서술어적 관형격 명사구로 나뉜다. 다음은 관형격 명사구가 표면구조에서 벗어나서 심층 구조에 변형하며 ‘NP1+ 의+ NP2’는 총 아홉 가지로 분류한다. 그리고 관형격 명사구가 통사적 기저문장 변형에서 유형과 양상을 검토하며 통 사적 수의적 경우는 네 가지, 의미적 수의적 경우는 네 가지로 나뉜다. 이런 분류를 통해 순수한 관형격 조사 ‘의’가 수의적 실현 경우에서 생략 의 형상을 자세히 볼 수 있는 연구 성과를 얻을 수 있다. 그리고 하나의 문장에서, 화자의 직관과 명사구 사용 상황에 따라 ‘의’가 강한 수의성 (possessiveness)을 나타내는 경우가 흔하다. 이러한 강한 수의성을 갖 는 ‘의’는 문장 내에서 기저 구조를 분석을 통해 ‘의’를 더 깊이 이해할 수 있다는 의미가 있다.

본고는 최근 새로운 융합교육 제도의 하나로 주목받고 있는 마이크로 디그리의 기본 개념과 의미에 대해 살펴보고, 국내외 마이크로디그리 교 육과정의 적용사례를 통해 향후 마이크로디그리 교육과정이 대안적 융합 교육으로 정착하기 위한 조건과 고려해야 할 점들에 대해 탐색하는 것을 목적으로 한다. 이를 위해 최근 정부의 소단위 학위과정 인정의 근거를 살펴보고, 국내외 마이크로디그리 도입 사례에 대한 비교·분석을 실시했 다. 교육기관의 규모와 적용범위, 교육목표, 운영주체 등을 중심으로 해 외와 국내 사례를 각각 비교했다. 해외의 경우, 대학보다는 주로 기업 및 연구기관이 운영 주체가 되는 대안학교의 형태로 운영되는 반면, 국내에 서는 마이크로디그리가 대학의 전공 및 교양교육과정을 보완하는 형태로 받아들여졌다는 점에서 상이점을 찾을 수 있다. 하지만 급변하는 사회 수요를 교육과정에 바로바로 적용할 수 있다는 장점을 가진 마이크로디 그리의 본질을 고려한다면, 사회 수요를 신속히 교육과정에 반영해 산업 현장과 대학 교육의 거리를 근거리로 유지·지속시킬 수 있는 보다 명확 하고 독립적인 학내 전담 운영 조직의 마련도 고려될 필요가 있다. 또한 본고에서는 마이크로디그리의 도입단계와 운영단계 각각에서 고려될 필 요가 있는 네가지 지점들에 대해서도 살펴보았다. 이를 통해 대안적 융 합교육으로서 마이크로디그리의 도입과 정착에 필요한 조건은 무엇인지 가늠해 보았다.

PURPOSES : This study aims to examine actual cases of providing detour information in accidental situations such as traffic accidents and road construction through a VMS installed on national highways in metropolitan areas with alternative routes, as well as cases of simultaneously providing travel time information on parallel paths such as national and regular highways. For each case, we analyzed whether the provision of VMS traffic information leads to route changes and substantial effects. METHODS : To analyze traffic changes on the main and detour roads based on the detour information provided on traffic accidents in actual cases, the traffic volume and speed on the accident day were compared with those on the same days and at the same time of the day (regular days) based on the VDS data of the main and detour roads. Cases providing more detour information on road construction were investigated by examining three time periods: one week from construction initiation and one week before and after the construction period (regular days). The traffic volume and speed on the main road were compared based on the VDS data, and those on the detour road were compared based on data made available by private entities. Regarding the cases of simultaneously providing drivers with comparative information on travel time over parallel sections of national and regular highways, traffic situation changes in highways were analyzed in the following special traffic control periods (New Year's Day, NY Day), during which congestion is expected due to heavy traffic: before and after the provision of comparative information for 2015 New Year's Day and 2016 NY Day. RESULTS : The detour rate related to route changes based on the detour information for traffic accidents was 35%. On the detour route, the traffic volume increases as traffic from the main road is absorbed. However, the average travel speeds did not differ significantly. When further detour information regarding a road construction project was provided, the detour rate from the main road was 21%. The travel speeds were similar, except on the first day of construction. Almost no changes were observed in the first section of the detour. The speed slightly decreased in the second section but did not significantly hinder the traffic flow. When comparative traffic time information on parallel routes (national highways and expressways) was provided, the traffic volume increased to some extent after the report was provided for every case. However, the data frequency rate in the 5-min unit, which was still under the congestion speed standard (40 km/h), decreased. This indicates that traffic congestion was significantly relieved. CONCLUSIONS : Previous studies on detour rates or route changes based on VMS traffic information have focused on VMS instruments on expressways. Although their estimates were based on simulated situations, this study used actual VMS installed on national highways. In addition, this study utilizes the existing case records of national highway ITS centers, covering traffic situation monitoring, measures for accidental situations, etc., in regular times or special traffic control periods, as well as statistical data, including ITS real-time traffic information. The analysis results of this study accurately represent situations on actual roads and can be utilized to analyze future ITS operation and installation project effects.

췌장암은 항암화학요법의 발전에도 불구하고 여전히 예후가 좋지 않으며, 5년 생존율은 13.9%에 불과하다. 저자들은 61세 여성 환자에서 고식적 항암화학요법 후 췌장암에 대한 완전관해가 이루어진 증례를 보고하는 바이다. 환자는 1개월 동안의 소화불량과 2 kg의 체중 감소 증상을 호소하여 내원하였고, 컴퓨터 단층촬영 검사에서 췌장 머리 부위에 18 mm 크기의 종괴가 확인되었다. 혈액검사 결과에서 간 기능 검사는 정상이었으나, CA 19-9 및 CEA 수치가 각각 3,965 U/mL와 38.2 ng/mL로 상승되어 있었다. 조직 획득을 위해 내시경초음파 유도 세침흡인조직검사를 시행하였고, 병리학적 검사 결과 췌장선암으로 확인되었다. 양전자 방출 단층촬영 및 췌장 자기공명영상을 포함한 추가적인 평가를 통해 간의 6번째 분절과 복막하부 림프절에 전이성 종괴가 확인되었다. 최종적으로, 환자는 4기 췌장암으로 진단되었다. 환자에게 보존적 화학요법으로 폴피리녹스 투여하였고, 치료 1년 후 잔여 종양은 사라졌다. 이후 수술 치료를 시행하였고, 현재 보조 항암화학요법을 시행중이다. 전이성 췌장암에서 항암화학요법으로 완전관해를 이룬 사례는 매우 드문 증례이기에 문헌고찰과 함께 보고하는 바이다.

호산구성 장염에 의한 급성 췌장염은 매우 드문 질환으로 증상 및 검사실 소견이 특별하지 않아 진단이 어렵다. 급성 췌장염의 원인이 명확하지 않은 경우, 가능한 원인으로 매우 드물지만 호산구성 위장염이 있을 수 있으며, 본 저자들은 호산구성 위십이지장염에 의해 발생한 재발성 급성 췌장염을 진단하고 류코트리엔 수용체 길항제로 치료하였던 증례를 문헌고찰과 함께 보고한다.

파골세포양 거대세포형 미분화 암종은 췌장암의 1%만을 차지하는 흔치 않은 암종으로 알려져 있다. 저자들은 39세 남자에게서 진단된, 수술 및 항암치료를 시행한 1예를 소개하고자 한다.

췌장 가성동맥류는 췌장염이나 췌장 수술과 연관되어 종종 생명을 위협하는 합병증으로 알려져 있다. 췌장 가성동맥류가 파열되면 치명적인 출혈을 유발할 수 있으며 높은 사망률과 관련이 있기 때문에 임상적 의심과 조기 진단이 환자의 임상 경과를 호전되게 할 수 있는 중요한 역할을 한다. 가성동맥류의 치료법 중 하나로 알려진 색전술은 효과적일 수 있으나, 췌장염과 관련된 가성동맥류 파열 환자의 색전술 치료 결과에 대한 국내 연구는 적다. 이에 췌장염으로 인한 가성동맥류 파열을 진단받고 색전술로 성공적으로 치료받은 환자들에 대한 증례를 보고한다.

Langerhans cell histiocytosis (LCH) is a rare disease that arises from an abnormal increase in histiocytes. Due to its rare occurrence, the diagnosis of LCH is often delayed or missed. This report presents a case of LCH in a 16-month-old girl. After biopsy, the patient’s previous medical records were obtained. The records described the presence of a yellowish plaque on the forehead since birth, a characteristic feature of LCH. Earlier knowledge of this medical history would have helped facilitate the diagnosis of LCH. This report aims to inform clinicians of the clinical and histopathological features of LCH in order to aid in the early diagnosis of this disease, which can occur in infancy.