Since July 2021, the Korea Radioactive Waste Agency has been conducting a safety case development study for the Korean deep geological repository program. The safety case includes generating scenarios in which radioactive materials from spent nuclear fuel repository reach the human biosphere by combining selective FEPs (Features, Events, and Processes). This safety case should be able to transparently explain the process in which conclusions have been drawn not only to stakeholders but also to the public by presenting safety arguments. The scenario development stage consisting of FEP screening, scenario generation, and uncertainty analysis procedures should have a database management system. Database management system was performed in countries such as Sweden, which obtained approval for the construction of spent nuclear fuel repositories, and the United States, where various preliminary research was carried out. Korea Atomic Energy Research Institute also has experience in designing and operating its own database, which has conducted preliminary research on disposal of the spent nuclear fuel. Currently, the safety assessment of the Korean spent nuclear fuel repository is in the early stages of research, but it is necessary to set up a basic framework for database design while the collection of FEP data from domestic and international preliminary studies is under development, and it is advantageous for efficient database construction and operation. Therefore, this paper presents the current status of database design considering completeness and transparency from the FEP screening stage to the scenario development stage in the safety assessment process of the Korean spent nuclear fuel repository. In this process, the functional requirements that the database should provide, the database schema capable of implementing them, and simple examples are presented together. The objectives of this database design are flexible FEPs management, high integrity and consistency, and expandability for linking with the safety case database. The FEP data to be inputted into the database includes a list of major opened FEPs, including International FEPs from Nuclear Energy Agency, which were referred for PFEPs (Project-specific FEPs), and PFEPs applied to POSIVA's Olkiluoto repository. As an additional function, queries from the database are used to visually express the process of deriving scenarios through Rock Engineering System, a widely known scenario generation methodology.

Korea Atomic Energy Research Institute (KAERI) has investigated Pyroprocessing technology in order to decrease the burden of disposal system and increase availability of useful radionuclides in the spent nuclear fuel (SNF) for future. The treatment and the disposal of SNF, however, are very sensitive issues socially. In addition, under the energy transition policy phasing out nuclear energy gradually there have been demands for alternatives so far. Thus various alternatives should need to be investigated in preparation for unexpected situations. This study has been conducted roughly in effectiveness point of view of alternative pre-managements for SNF, not pyroprocessing technology, in disposal system, consisting of three stages according to the degree of burden in disposal system. Stage I is the case for making safety increase with removing highly-mobile radionuclides from SNF. Stage II is the case for eliminating high-heat radionuclides additionally, alleviating thermal risk in the disposal system. And Stage III is the case for recovering Uranium in addition to Stage II. These options of pre-management are thought to be able to provide an intuitive strategy for effective diversification of the disposal system. Because several types of waste form from pre-management make it possible to develop the effective, newly-composed waste disposal system according to the properties of radionuclides. And the processability of SNF through pre-management might be combination with available core-drilling technology, being able to design various disposal system as well. Even though the whole, detailed unit processes have not designed yet, mass balance and distributions of radionuclides are performed under the appropriate assumption of engineering processes. As a first step the alternative approaches for SNF pre-management for disposal system might be expected to be widely used in implementing SNF management policy in the future.

Molten Salt Reactor (MSR) is one of the generation-IV advanced nuclear reactors in which hightemperature molten salt mixture is used as the primary coolant, or even the fuel itself unlike most nuclear reactors that adopt solid fuels. The MSR has received a great attention because of its excellent thermal efficiency, high power density, and structural simplicity. In particular, since the MSR uses molten salts with boiling points higher than the exit temperature of the reactor core, there is no severe accident such as a core melt-down which leads to a hydrogen explosion. In addition, it is possible to remove the residual heat through a completely passive way and when the fuel salt leaks to the outside, it solidifies at room-temperature without releasing radioactive fission products such as cesium, which make the MSR inherently safe. Both fluoride and chloride mixtures can be used as liquid fuel salts by adding actinide halides for MSRs. However, the MSRs using chloride-based salt fuels can be operated for a long time without adding nuclear fuel or online reprocessing because the actinide solubility in chloride salts is about six times higher than that in fluoride salts. Therefore, the chloride-based MSRs are more effective for the transmutation of long-lived radionuclides such as transuranic elements than the fluoride-based MSRs, which is beneficial to resolve the high radioactive spent nuclear fuel generated from light water reactors (LWRs). This paper examines liquid fuel fabrication using an improved U chlorination process for the chloride-based MSRs and presents the strategy for the management of gaseous fission products generated during the operation of MSR.

Since the commercial operation of Kori unit 1 in 1978, nuclear power has provided cheap, stable and clean electricity in South-Korea. For decades, the discussion about the spent fuel management has been dominated and the government is responsible for on-going research and development (R&D) related to long-term spent nuclear fuel management. The effective management of spent fuel should be applied from the early stage of the R&D process to licensing phases with the step-by-step evaluation system. As part of follow-up efforts after the Fukushima nuclear accident, the Nuclear Promotion Commission and Nuclear Safety Commission were divided in function as an independent agency for enhancing national nuclear safety and security, which aims to protect the public and environment from undue radiological hazard. The national spent fuel project must have a vibrant program for spent fuel management. Due to the nature of these projects, the establishment of a ‘conformity assessment’ system that collects the opinions from the licensing organisations on the results of research projects from the initial R&D stage should be applied advertently in order to efficiently conduct research projects and enhance public confidence. For the government-led project for spent nuclear fuel management, the adequacy and applicability of its technology R&D as well as its sustainability that includes financial, social and environmental performance measures should be evaluated in each stage. The institutionalisation arrangement, so called ‘conformity assessment system’ for the development of a national spent nuclear fuel management plan and related technology should be developed. This study aims to propose the basic principles for the introduction of the conformity assessment system: (1) national management responsibility, (2) spent fuel management project scope, (3) its management main principles, (4) project implementation system, (5) final management project scope and securing financial resources.

The nuclear facilities sites handling radioactive materials are contaminated due to accidents or its activities. Since the experimental reactor was operated in Idaho, USA in 1951, nuclear power and its related activities were carried out in many countries. Thus, the legacy sites in which radioactive materials have been deposited are a matter of public concern. As a result of the operation of facilities related to the use of nuclear energy, it is faced with the restoration of the environment containing radioactive wastes. In particular, the activities carried out in the early years caused its contamination of the sites and areas with significant releases of fission products and natural radioactive wastes adventitiously or intentionally due to the lack of its technology and the unclear radiation risks. In addition, nuclear weapons tests conducted in the 1950s and 1960s and the Chernobyl power plant accident in 1986 caused radioactive contamination in the Pacific Ocean and extensive territories in Europe. Accordingly, the IAEA discussed the restoration of the contaminated areas at the conference on the radiation legacy of the 20th Century in terms of environmental restoration (RADLEG-2000) held at Moscow, Russia in October 2000 and its cases from the former Soviet Union and Eastern Europe were reported. Also, the Nuclear Energy Agency (NEA) has discussed the potential issues on the legacy sites occurring radioactive materials and suggested that these sites should be managed in an open, transparent and consistent manner in order to build sustainable solutions with trust. However, there is currently no overall regulatory system for the management of legacy sites in Korea. The TRIGA Mark-II research reactor, which was commissioned in 1962, was decontaminated and dismantled in 1997. As such, it is necessary to consider the regulatory system related to the existing legacy site. Most of all, the legacy site management and regulatory standards of facilities that have operated in the past and are not currently operating or that deal with natural radioactive materials should be established. Also, the dismantling of NK’s nuclear facilities and management of related radioactive waste, particularly NK’s uranium mines and refining facilities particularly at Pyongsan and Bakcheon in NK are one of the key issue on the North Korea’s denuclearization. In this study, the international standards on the reuse of the legacy site after dismantling are analyzed, and its regulatory considerations used for domestic application are suggested.

The ROK conducts several export procedures, communications in connection with transfers; exchange of information on export plan, shipments, and receipt of nuclear materials, in accordance with bilateral Nuclear Cooperation Agreements (NCA) and Administrative Arrangements (AA) signed with US, Canada, and Australia. Also, the inventory amount of items subject to NCA has reported annually. This study reviewed the export procedures and management methods for spent nuclear fuel subject to NCA. The re-transfer procedures start with obtaining consent from the original exporting country. It is impossible to retransfer nuclear material without consent, whether long-term or individual case-bycase. If the material has multiple obligations, prior consent from all of those countries is required. Therefore, it is necessary to clarify the foreign obligated materials correctly. In general, nuclear fuel is subject to multiple obligations of all countries through which the materials have passed during the front-end fuel cycle. Then the new obligations are imposed on those irradiated materials or their by-products after ‘used-in’ or ‘produced through the use of ’ equipment subject to NCA. For example, fuel assemblies manufactured under CANDU fuel fabrication equipment subject to ROK-Canada NCA or burned in nuclear reactors where US equipment is installed have obligations based on Canada or US agreements. In order to impose obligation to irradiated materials, the principle of proportionality is applied as stipulated in each Agreement. According to the AA between US and ROK, nuclear materials used in the equipment transferred under the Agreement and produced through them are differently controlled. After the cycle in the reactor with US-made equipment, uranium in the irradiated fuel is considered a material used in the equipment. So it would be appropriate to apply obligation proportionality according to its origin, regardless the US-made equipment. Meanwhile, the obligation under US NCA is given to the entire amount of produced plutonium in the irradiated fuel. Although the contribution to the production of fuel is to be discussed case-by-case basis in the case of Canadian obligation, applying a similar method is proper. Since the fuel is burned in the form of bundles or assemblies, it is impossible to separate the spent fuel into uranium and plutonium physically. However, as discussed above, to clarify the rights and obligations pursuant to Agreement and ensure accuracy in inventory management, the obligation codes should be imposed on irradiated fuel as not a single item but separated individual substance of materials. Moreover, when an obligation swap occurs for the irradiated fuel, its movement and combustion history should be considered to prevent confusion in confirming multiple obligations and implementing export procedure.

In April 2015, the government of the Republic of Korea and the United States of America signed a new Nuclear Cooperation Agreement (NCA). Subsequently, in April 2016, the Nuclear Safety and Security Commission (NSSC) of the ROK and the Department of Energy (DOE) of the US signed the Administrative Agreement (AA) under the new Nuclear Cooperation Agreement. Accordingly, when Korea imports items subject to the Korea-US agreement, it is required to determine the inventory of imported agreement items and notify the United States of the inventory amount every year. In addition, when re-exporting an agreement item to a third country, prior consent of the original exporting country (USA) must be obtained. Nuclear companies that import items subject to the Korea-US Atomic Energy Cooperation Agreement must report their inventory to the government every year, but the standards and procedures for managing the inventory are not clearly stipulated in the national law. This makes it difficult for the government to verify the adequacy of the report submitted by nuclear companies, adding to the administrative burden on both the government and the companies. Accordingly, it is required for the government to establish and operate a system for history management system for import and export items subject to the agreement so that related information can be recorded and managed at each stage, such as first import of items to Korea, generation, disposal, and exports to third countries. This system provides history management functions such as initial import information record for items imported through import/export procedures according to administrative agreements, change of owned company due to domestic movement, deletion of inventory due to loss/disposal, deletion of inventory due to export or addition of inventory due to derived materials. Through this system, operators can easily manage agreement items, and the government can obtain reliable information on agreement items in close to real-time. In addition, when this system applies to exports of items subject to the agreement, the number of items subject to the agreement exported by Korea can be provided first so that the importing country can more quickly check the items subject to the agreement. It is expected to contribute to securing control of the items subject to the agreement and reducing concerns over nuclear proliferation.

최근 회전 회전기계의 건전성 관련 연구가 활발하게 진행중이며, 조선업의 대표적인 회전기계인 갠트리 크레인에도 이를 적용하고자 하는 연구가 활발하게 진행되고 있다. 하지만 조선업의 갠트리 크레인의 경우 상대적으로 낮은 RPM으로 구동되고 잦은 운 전과 정지가 이루어지며 충격, 소음 등의 외부환경 인자가 측정 데이터에 영향을 크게 미쳐 오차를 발생시킬 수 있다. 본 연구에서는 조선업의 내업공정에서 사용되는 갠트리 크레인의 Hoist 모사장비를 제작하여, 운전조건(RPM) 변화와 데이터 획득 센서의 위치 차이가 획득 데이터에 미치는 오차를 통계적으로 분석하였다. 연구결과 상대적으로 낮은 운전조건에서는 센서 위치 차이에 따른 획득 데이터 의 오차는 크게 발생하지 않았으나, 상대적으로 높은 운전조건에서는 획득 데이터의 오차가 크게 발생하는 것으로 확인하였으며, 회전 기계의 데이터 획득 시 운전조건과 획득 센서위치가 획득 데이터에 영향을 미치는 것으로 확인하였다.

The purpose of this paper is to propose part management and standardization to reduce cost and increase compatibility of parts through standardization and standardization of parts to be applied to urban air mobility(UAM) systems, Personnel Air Vehicle(PAV), Vertical Take-Off and Landing (VTOL), and so on. In other words, parts used in the urban air transportation system must be verified from the initial design stage in accordance with the aviation standard, and a systematic management system for various parts must be established to secure stability and improve quality. Therefore, as a system similar to the aviation component management system, it should be thoroughly managed for urban aviation components.

Galactosemia is a rare genetic metabolic disease caused by galactose and its metabolites generated during carbohydrate metabolism, which is relatively rare in Asian countries, including Korea. Patients with galactosemia should be treated with a galactose-restricted diet. However, information is lacking about the exact content of galactose in food, and dietary guidelines for patients with galactosemia in Korea. This study aims to recognize the difficulties faced by parents and clinical experts of patients with galactosemia, and understand their demands. Totally, 5 parents of children diagnosed with galactosemia and 5 clinical professionals participated in the focus group interviews. The parents’ interview focused on the daily life of the patient, which included diet and social difficulties. The clinical experts mainly answered about medical care, including the number and status of patients, and their suggestions for effective treatment. Most parents were worried about social isolation due to conflicts in the family as well as in society due to a lack of understanding of the disease. The clinical experts stated the absence of a disease management system as the greatest problem. An integrated support system for patients with galactosemia, which includes appropriate dietary guidelines by considering the domestic environment, is required.

Endoscopic ultrasonography-guided intervention has gradually become a standard treatment for peripancreatic fluid collections (PFCs). However, it is difficult to popularize the procedure in Korea because of restrictions on insurance claims regarding the use of endoscopic accessories, as well as the lack of standardized Korean clinical practice guidelines. The Korean Society of Gastrointestinal Endoscopy (appointed a Task Force to develope medical guidelines by referring to the manual for clinical practice guidelines development prepared by the National Evidence-Based Healthcare Collaborating Agency. Previous studies on PFCs were searched, and certain studies were selected with the help of experts. Then, a set of key questions was selected, and treatment guidelines were systematically reviewed. Answers to these questions and recommendations were selected via peer review. This guideline discusses endoscopic management of PFCs and makes recommendations on indication for the procedure, pre-procedural preparations, optimal approach for drainage, procedural considerations (e.g., types of stent, advantages and disadvantages of plastic and metal stents, and accessories), adverse events of endoscopic intervention, and procedural quality issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This will be revised as necessary to address advances and changes in technology and evidence obtained in clinical practice and future studies.

Recently, due to the change to SASB(Sustainability Accounting Standards Board) and GRI(Global Reporting Initiative) Standards 2021, the paradigm for non-financial information disclosure is changing significantly, with the number of ESG topics and indicators that must be disclosed by industry from an autonomous material topic selection method. This study revealed that the number of compulsory topics in the oil and gas industry by GRI standards 2021 is up to 2.4 times higher than the average number of material topics disclosed when domestic companies publish sustainability reports using GRI Standards 2020. In the oil and gas industry, I analyzed the similarities and differences between the GRI standards 2021 and the ESG topics covered by SASB by environmental, social, economic, and governance areas. In addition, the materiality test process, which is different in GRI standards 2021, is introduced, and the issues included in the following 10 representative ESG-related initiatives are summarized into 62 and suggested improvement plans for materiality test used in the topic pool.

본 연구는 아파트 단지에 식재된 조경수의 시계열 변화를 파악하고 조경수 중 소나무의 수요를 예측하기 위하여 수행되었다. 2003년부터 2020년까지 수도권의 아파트 단지에 사용된 수목의 종수는 평균 51종이며 2000년대 중후반에 비하여 2010년대 후반에는 다양한 종류의 수목이 사용되었다. 식재 수량은 평균 149,567주/1단지이며 시계열 변화가 두드러지지 않는다. 상록수와 낙엽수의 수종 비율은 2:8 이지만 식재된 수량은 3.5:6.5의 비율이었다. 상록수는 낙엽수에 비하여 한 수종의 식재량이 많은 반면에 낙엽수는 상록수에 비하여 상대적으로 다양한 수종이 식재되고 있다. 교목과 관목의 수종 비율은 6:4이지만 식재량은 관목 97.6%로 식재량에 비해 식재된 수목의 종류는 다양하지 않다. 조경수 중에서도 선호도와 이용가치가 높은 소나무의 식재현황을 분석하면 식재 수량은 증가하는 경향이며 특히, 근원직경이 큰 소나무의 식재 비율이 증가하고 있다. 아파트 단지의 소나무 식재수요를 예측하면 식재량은 지속적으로 증가할 것이며 특히 근원직경 40㎝ 이상의 특수목의 수요가 증가할 것이다. 이러한 조경수의 수요변화에 대응하여 다양한 식물소재를 발굴하고 생산할 수 있는 전략이 요구된다. 특히 지속적으로 소나무의 대형화가 예측되므로 시장에서 요구하는 수형과 규격을 갖춘 소나무가 적기에 공급될 수 있도록 생산관리가 이루어져야 할 것이다.