In the design of a spent-fuel (SF) storage, the consideration of burnup credit brings the benefits in safety and economic views. According to it, various SF burnup measurement systems have been developed to estimate high fidelity burnup credit, such as FORK and SMOPY. Recently, there are a few attempts to localize the SF burnup measurement system in South Korea. For the localization of SF burnup measurement systems, it is very important to build the isotope inventory data base (DB) of various kinds of SFs. In this study, we performed DeCART2D/MASTER core follow calculations and McCARD single fuel assembly (FA) burnup analyses for Hanbit unit 3 and confirmed the characteristic of the isotope inventory over burnup. Firstly, the core follow calculations for Cycles 1~7 were performed using DeCART2D/MASTER code system. The core follow calculation is very realistic and practical because it considers the design conditions from its nuclear design report (NDR). Secondly, the Monte Carlo burnup analyses for single FAs were conducted by the McCARD Monte Carlo (MC) transport code. The McCARD code can utilize continuous energy cross section library and treat complex geometric information for particle transport simulation. Accordingly, the McCARD code can provide accurate solutions for burnup analyses without approximations, but it needs huge computing resources and time burden to perform whole-core follow calculations. Therefore, we will confirm the effectiveness of the single McCARD FA burnup analyses by comparing the DeCART2D/MASTER core follow results with the McCARD solution. From the results, the use of single FA burnup analyses for the establishment of the DBs will be justified. Various FAs, that have different 235U enrichments and loading pattern of fuel rods and burnable absorbers, were considered for the burnup analyses. In addition, the results of the sensitivity analyses for power density, initial enrichment, and cooling time will be presented.

기후 변화의 가속화로 국내 제주 및 남부 지방을 중심으로 열대 및 아열대 작물의 재배 및 소비가 증가하는 추세이다.오크라는 식용적 가치가 있을 뿐만 아니라, 품종별 고유의 꼬 투리와 잎의 색은 관상적 가치가 있어 조경 식물로 많이 사용 되고 있다. 본 연구는 도심 내 옥상 온실에 관상식물인 오크 라를 도입하기 위해 피트모스와 펄라이트 비율에 따른 기초 종자 발아 및 육묘기 실험을 진행하였다. 피트모스와 펄라이 트 비율은 PT:PL=1:2, 1:1, 2:1, 4:1 네 가지로 조성하였다. 발 아율은 파종 후 7일차부터 다른 처리구에 비해 피트모스:펄라 이트=1:2의 처리구에서 가장 높았다. 파종 후 28일차와 70일 차에 줄기길이, 경경, 뿌리길이, 지상부와 지하부의 생체중과 건물중 그리고 엽면적은 피트모스:펄라이트=1:2 처리구에서 가장 높았다. 그러나, 파종 후 56일 이후부터 엽수는 피트모 스:펄라이트=1:2, 2:1, 4:1 처리구에서 감소하였다. 피트모스: 펄라이트=1:1, 2:1, 4:1 처리구에서 식물이 필요로 하는 피트 모스의 비율이 지나치게 높아 높은 피트모스 비율로 인하여 수분함수량이 과도하게 높아 식물이 고사한 것으로 판단된다. 따라서 오크라를 관상식물로 활용하기 위해서는 피트모스와 펄라이트를 1:2로 혼합한 배지가 가장 적합하다.

털부처꽃(Lythrum salicaria L.)은 전국에 분포하는 다년생 초본식물로 척박하고 습한 지역을 포함한 다양한 환경에서 잘 자라는 것으로 알려져 있다. 따라서 하천변, 척박지에서 정원 용, 화훼용 및 관상용 식물로 이용이 가능하다. 본 연구는 털 부처꽃의 적정 육묘 조건(토양종류, 플러그 트레이 셀 크기,파종립수, 액비농도 및 차광)을 조사하였다. 대조구(원예상토) 에서 재배된 유묘의 생육이 가장 우수하였다. 반면 피트모스 와 펄라이트의 혼합용토는 육묘기간이 지속되면서 생육수치 가 감소하는 경향을 나타냈다. 셀 크기는 용적이 가장 큰 162 셀에서 재배된 유묘의 생육이 우수하였으나, 200셀과 288셀에 서 자란 묘도 건강했다. 한편 유묘의 결주발생을 고려하면 셀 당 2립을 파종하는 것이 적합하였다. 액비 처리는 유묘의 생 육을 촉진하였다. 특히 Hyponex 1000배는 초장, 줄기직경, 엽수, 마디수, 근장, 지상부 생체중 및 지하부 생체중을 증가 시켰다. 또한 유묘의 생육은 55% 차광 하에서 우수하였다. 따 라서 털부처꽃의 가장 효과적인 생육조건은 원예상토가 충진 된 288셀 플러그 트레이에 셀 당 2립을 파종하고 Hyponex 1000배를 시비하면서 55% 차광 하에서 재배하는 것이었다.

Minuartia laricina (L.) Mattf. is a Korean native plant with high potential as a commercial flowering potted plant due to its compactness and long flowering duration. However, because this plant is a groundcover, it is susceptible to lodging and leggy growth. Therefore, this study investigated the effects of plant growth retardants (PGRs) on the inhibition of stem elongation and flowering characteristics of M. laricina. Commercial products, Trimmit, Cycocel, and B-Nine, were used for the exogenous PGR application of paclobutrazol (PBZ), chlormequat chloride (CCC), and daminozide (DMZ), respectively. Application concentrations were 50 and 100 mg·L-1 for PBZ; 100, 500, and 1,000 mg･L-1 for CCC; and 500, 1,000, and 2,000 mg·L-1 for DMZ. Paclobutrazol was the only PGR that inhibited stem elongation. The stem lengths of the plants treated with 50 or 100 mg·L-1 PBZ were 2.2 cm (13%) or 9.8 cm (57%) shorter, respectively, than those of the control. 50 mg·L-1 PBZ retarded stem growth effectively without negatively affecting flowering or other growth parameters, whereas 100 mg·L-1 PBZ caused excessive dwarfing and significantly reduced flowering by 59%. CCC and DMZ applications were ineffective for growth control. Flowering time was accelerated with most PGRs, except for 2,000 mg·L-1 DMZ, reducing the time to flowering by 2–8 days. These results indicate that the stem growth of M. laricina was successfully inhibited with PBZ but not with CCC or DMZ. Thus, we concluded that a single application of 50 mg·L-1 PBZ or similar treatment is effective in miniaturizing M. laricina without causing harm to its growth or aesthetic value, such as the flower number. Additionally, because CCC and DMZ are not persistent in the growing medium, testing multiple application times for these PGRs is crucial.

Although the effect of elevated carbon dioxide (CO2) on Phalaenopsis plant flowering, biomass, and photosynthesis has received intensive study, whether elevated CO2 affects plant requirements and sensitivity to potassium sulfate (SOP) during the reproductive growth stage remains unclear. To evaluate the combined effect of CO2 and SOP provision on crassulacean acid metabolism orchids, we cultivated Phalaenopsis Queen Beer ‘Mantefon’ under ambient and elevated CO2 treatments (≈ 400 or ≈ 720 μmol×mol-1, respectively) and four levels of SOP supply for 20 weeks after treatments (WAT): potassium and sulfate levels by 10.41 and 1.96 mmol·L-1 (SOP1), 5.98 and 0.90 mmol·L-1 (SOP2), 12.80 and 1.96 mmol·L-1 (SOP3), and 14.83 and 3.16 mmol·L-1 (SOP4), respectively. The number of floral buds and flowers decreased in the plants grown under elevated CO2 than in those grown under ambient CO2, regardless of the SOP level; however, the reduced production of floral buds and flowers did not affect the dry mass of shoot, root, and spike at 20 WAT. There were significant interactive effects of CO2 and SOP on root biomass accumulation and net CO2 uptake. The stimulation of biomass partitioning on the root, as a sink source, observed due to the uptake of elevated CO2 was improved under increased SOP supply. Under ambient CO2, the leaf critical SOP level was SOP1 for root and spike biomass accumulation. Plants grown under elevated CO2 were more sensitive to SOP treatments, with higher essential leaf levels of SOP.

Polarimetric measurements of the lunar surface from lunar orbit soon will be available via Wide-Field Polarimetric Camera (PolCam) onboard the Korea Pathfinder Lunar Orbiter (KPLO), which is planned to be launched in mid 2022. To provide calibration data for the PolCam, we are conducting speckle polarimetric measurements of the nearside of the Moon from the Earth’s ground. It appears that speckle imaging of the Moon for scientific purposes has not been attempted before, and there is need for a procedure to create a “lucky image” from a number of observed speckle images. As a first step of obtaining calibration data for the PolCam from the ground, we search for the best sharpness measure for lunar surfaces. We then calculate the minimum number of speckle images and the number of images to be shift-and-added for higher resolution (sharpness) and signal-to-noise ratio.