Spent nuclear fuel management is a high-priority issue in South Korea, and addressing it is crucial for the country’s long-term energy sustainability. The KORAD (Korea Radioactive Waste Agency) is leading a comprehensive, long-term project to develop a safe and effective deep geological repository for spent nuclear fuel disposal. Within this framework, we have three primary objectives in this work. First, we conducted statistical analysis to assess the inventory of spent nuclear fuel in South Korea as of 2021. We also projected future generation rates of spent nuclear fuels to identify what we refer to as reference spent nuclear fuels. These reference spent nuclear fuels will be used as the design basis spent fuels for evaluating the safety of the repository. Specifically, we identified four types of design basis reference spent nuclear fuels: high and low burnup from PLUS7 (with a 16×16 array) and ACE7 (with a 17×17 array) assemblies. Second, we analyzed radioactive nuclides’ inventory, activities, and decay heats, extending up to a million years after reactor discharge for these reference spent nuclear fuels. This analysis was performed using SCALE/TRITON to generate the burnup libraries and SCALE/ORIGEN for source term evaluation. Third, to assess the safety resulted from potential radioactive nuclides’ release from the disposal canister in future work, we selected safety-related radionuclides based on the ALI (Annual Limit of Intake) specified in Annex 3 of the 2019-10 notification by the NSSC (Nuclear Safety and Security Commission). Conservative assumptions were made regarding annual water intake by humans, canister design lifetime, and aquifer flow rates. A safety margin of 10-3 of the ALI was applied. We selected 56 radionuclides that exceed the intake limits and have half-lives longer than one year as the safety-related radionuclides. However, it is crucial to note that our selection criteria focused on ALI and half-lives. It did not include other essential factors such as solubility limits, distribution coefficients, and leakage processes. So, some of these nuclides can be removed in a specific analysis area depending on their properties.

제3차 전력수급기본계획에 근거하여 현재 운영중이거나 계획중인 원자력발전소에서 발생할 사용후핵연료의 양과 특성을 추정하였다. 본 연구에서 고려된 대상 특성은 핵연료집합체에 대한 제원, 핵연료봉 배열, 무게, 235U 초기 농축도 및 방출연소도이다. 이들은 파이로공정 시설을 설계하는데 필수적인 것이다. 2077년말까지 가압경수로 사용후핵연료의 예상발생량은 약 23,000 tU이 될 것으로 보인다. 235U 초기 농축도 4.5 wt.% 이하를 갖는 사용후핵연료의 비율은 전체 발생량의 약 95%를 차지할 것이며, 16×16 배열을 갖는 핵연료집합체는 74%를 차지할 것 같다. 현재 사용후핵연료의 평균연소도는 45 GWd/tU인데 반해, 2010년대 중·후반 이후 발생할 사용후 핵연료의 평균연소도는 55 GWd/tU이 될 것 같다. 이상의 결과에 따라 파이로공정 시설의 설계를 위한 기준 사용후핵연료를 도출하였다. 예상 사용후핵연료는 21.4 cm × 21.4 cm의 단면적, 453 cm의 길이, 672 kg의 질량, 4.5 wt.%의 235U 초기 농축도 및 55 GWd/tU의 방출연소도를 갖는 16×16 한국표준형연료가 타당할 것으로 판단된다.

겨울철 온실의 기본적인 열에너지원인 일사를 최대한 확보하도록 하는 은실의 지붕형상을 결정하기 위해 유전알고리즘 및 광투과율 전산모델을 이용한 최적화기법을 이용하여 설치지역, 피복재료특성, 온실의 기본치수등이 주어졌을 때 지붕경사각, 경간폭비의 최적조합을 결정할 수 있도록 하는 최적설계를 수행하였다. 수원지방에 위치한 경간폭 6m의 2연동 동서동 온실 및 단동 온실을 가정하여 최적화를 수행한 결과 경사각, 폭비 순으로 2연동, 단동 온실에 대해 각각 40.861≒40 。 / , 0.4806≒0.5, 37.490≒37 。 / , 0.7748≒0.78의 결과를 얻을 수 있었다. 광투과율 문제를 예로 적용해 본 결과 직접 전산모델을 호출하여 최적화를 수행하는 유전알고리즘의 기법은 온실환경의 해석을 위해 연구되어온 다양한 분야의 전산모델들을 종합적인 온실의 최적설계에 활용하도록 하는데 유용한 기법이 될 것으로 판단되었다.판단되었다.

Computerized visual database construction of architectural precedents has just begun in some research institutes in the world. In Korea the first visual database has shown its testl version by S architectural design firm in september 1996. In this article the author discusses the historical contexts and the recent computerization cases, the traits, the uses and the limits of architectural visual database system of precedents. The forms and contents of data fields in two cases are compared with a focus on the description of architectural traits of each data entry. Compared to the KIA format, the S database has better performance for architectural design reference because it collects more pictures and drawings and larger texts for the field of architectural chracteristics. But this latter also is constrained by its capacity of memory and so lacks the reciprocity of the DOORS in the Graduate School of Design, Harvard University. A visual database system which has more flexible allocation of memory and respondent with the users is yet to be prepared. But this system also should be maintained by some experts in architectural history, theory and criticism, because their knowledge is essential for selection of precedents and revision of the data description. A full-fledged electronic visual database in architecture will not only save much effort for the architect, but also will change the architects' design behavior. Nevertheless this does not mean the automatic promotion of architects' creativity.

In this study, the tendency of flow characteristics according to the mixing design of mortar and mortar standard reference materials was analyzed based on the constituents of the standard reference materials for mortar. As a result, the plastic viscosity of the mortar tends to be maintained according to the amount of fine aggregate, while the yield value tends to increase greatly. On the other hand, in the case of the standard reference materials for mortar, the plastic viscosity tends to increase largely according to the amount of fine aggregate substitutes, while the yield value tends to be almost maintained.

Meanwhile, reference evapotranspiration(ET0) is important information for agricultural management including irrigation planning and drought assessment, the database of reference evapotranspiration for future periods was rarely constructed especially at districts unit over the country. The Coupled Model Intercomparison Project Phase 5 (CMIP5) provides several meteorological data such as precipitation, average temperature, humidity, wind speed, and radiation for long-term future period at daily time-scale. This study aimed to build a database for reference evapotranspiration using the climate forecasts at high resolution (the outputs of HadGEM3-RA provided by Korea Meteorological Administration (KMA)). To estimate reference evapotranspiration, we implemented four different models such as FAO Modified Penman, FAO Penman-Monteith, FAO Blaney-Criddle, and Thornthwaite. The suggested database system has an open architecture so that user could add other models into the database. The database contains 5,050 regions’ data for each four models and four Representative Concentration Pathways (RCP) climate change scenarios. The developed database system provides selecting features by which the database users could extract specific region and period data.

현재 운영되고 있는 해양용 DGPS 시스템은 하드웨어 RSIM 방식으로서 DGPS 구조개선시 고려해야 할 위성항법시스템의 다원화와 미래 해양 사용자의 최소 요구성능을 만족시킬 수 있는 기술 적용에 효율적이지 못하다는 문제가 있다. 본 논문에서는 이러한 문제를 해결하기 위하여 소프트웨어 RSIM 방식으로 해양용 DGPS 시스템을 구조개선하는 방안을 연구한다. 이를 위해 본 논문은 해양용 DGPS 시스템에 적합한 소프트웨어 RSIM 방식을 제안하고, 제안한 방법의 기술적 타당성 분석을 위하여 광대역폭, 높은 표본화 주파수, 데이터 고속전송 사양을 갖는 RF 모듈과 DSP 모듈을 제작하며, 이를 이용하여 제안한 방법을 적용한 해양용 DGPS 시스템을 구현한다. 그리고 신호처리 소요시간 분석을 통하여 개인용 컴퓨터 환경에서 제안한 소프트웨어 RSIM 방식이 실시간으로 운영됨에 문제가 없음을 보인다. 마지막으로 본 논문은 제안한 방법으로 설계된 DGPS 시스템의 보정정보 정확도가 RTCM 221-2006-SC104-STD을 통해 규정된 국제기구 요구성능을 만족시키고 있음을 확인한다.