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.

Even though a huge amount of spent nuclear fuels are accumulated at each nuclear power plant site in Korea, our government has not yet started to select a final disposal site, which might require more than several km2 surface area. According to the second national plan for the management of high-level radioactive waste, the reference geological disposal concept followed the Finnish concept based on KBS-3 type. However, the second national plan also mentioned that it was necessary to develop the technical alternatives. Considering the limited area of the Korean peninsula, the authors had developed an alternative disposal concepts for spent nuclear fuels in order to enhance the disposal density since 2021. Among ten disposal concepts shown in the literature published in 2000’s, we narrowed them to four concepts by international experiences and expert judgements. Assuming 10,000 t of CANDU spent nuclear fuels (SNF), we designed the engineered barriers for each alternative disposal concept. That is, using a KURT geological conditions, the engineered barrier systems (EBS) for the following four alternative concepts were proposed: ① mined deep borehole matrix, ② sub-seabed disposal, ③ deep borehole disposal, and ④ multi-level dispoal. The quantitative data of each design such as foot prints, safety factors, economical factors are produced from the conceptual designs of the engineered barriers. Five evaluation criteria (public acceptance, safety, cost, technology readiness level, environmental friendliness) were chosen for the comparison of alternatives, and supporting indicators that can be evaluated quantitatively were derived. The AHP with domestic experts was applied to the comparison of alternatives. The twolevel disposal was proposed as the most appropriate alternative for the enhancement of disposal efficiency by the experts. If perspectives changes, the other alternatives would be preferred. Three kinds of the two-level disposal of CANDU SNF were compared. It was decided to dispose of all the CANDU spent nuclear fuels into the disposal holes in the lower-level disposal tunnels because total footprint of the disposal system for CANDU SNF was much smaller than that for PWR SNF. Currently, we reviewed the performance criteria related to the disposal canister and the buffer and designed the EBS for CANDU SNF. With the design, safety assessment and cost estimates for the alternative disposal system will be carried out next year.

In the present work, a three-phase AC arc plasma torch system is proposed to separate inorganic radioactive materials from the organic liquid waste. For this purpose, first, assuming the resistance of arc plasma ranges between 0.1 and 0.2 ohm, we designed a three-phase AC arc plasma power supply with the power level of 20 kW. Then, a three phase arc plasma torch consisting of three carbon rods with the diameter of 20 mm was designed and mounted on a cylindrical combustion chamber with the inner diameter of 150 mm. Detail design and basic performance of the plasma system were presented and discussed for application to the treatment of radioactive slurry wastes.

현재 대부분의 게임은 가상공간에서만 이루어지기 때문에 사용자의 실질적인 움직임이 없이 단순한 조작으로 수행되며, 이로 인해 사용자의 신체 및 정신에 다양한 부작용이 발생한다. 대 체 현실 게임은 기존 온라인 게임과 달리 가상 공간과 현실 세계를 연계하여 기존 게임의 부작 용을 완화할 수 있는 새로운 게임 장르이며, 게임 참여자간의 사회적 친밀감의 증가로 단순한 게임을 넘어서 새로운 사회적 유대를 형성하는 수단이 될 것으로 기대되고 있다. 본 논문에서 는 모바일 기기와 NFC 태그를 활용한 대체 현실 게임의 실제 구현을 보인다. 이를 위해 대체 현실 게임을 제작하기 위한 새로운 편집기와 이를 플레이하기 위한 모바일 기기 기반의 게임 실행기를 구현하였으며, 편집기를 통해 제작된 게임은 모바일 게임 실행기를 통하여 실행된다.

산업 현장에서는 디자인 고유 영역의 변화와 확장을 거치면서 디자인 능력과 구현에 있어서 보다 다양하고 심도 있는 전문기술인력 양성을 필요로 한다. 그러나 급격한 디자인 교육의 양적 팽창은 질적 저하를 초래한 면이 있어, 디자인 산업 변화에 대응한 다양화, 특성화, 차별화 된 교육과 교육의 내실화가 필요하다. 또한 산업계의 요구와 현장 내용을 교과목으로 반영하여 학교와 현장의 갭을 극복, 디자인 문제 파악과 프로세스 관리능력을 갖춘 디자이너의 배출을 위해 현장의 요구에 따른 교과과정 및 교과목 연구가 필요하다.

본 연구는 물리적인 방법을 이용하여 설계갈수량을 추정할 수 있는 방법을 제안한 것이다. 가뭄기간과 갈수유출사상이 상사하다는 전제하에 재현기간을 감수시간으로 변환 할 수 있는 모형을 유도하였다. 또 계측지점이나 미계측지점에 적용할 수 있는 감수모형을 제안했다. 본 감수시간 모형의 매개변수는 기후조건치, 유역특성치, 유출특성치 등이고 감수모형의 매개변수는 초기유량, 감수상수이다. 본 모형을 용담수위표 지점과 다른 임시관측 지점에 적용해 본 결과 유량관측 기