Protaetia brevitarsis larvae have been widely used for traditional medicine and food in East Asia. This research comprised two experiments. The first experiment compared the growth in densities (10, 20, 30 larvae), substrates (commercial, self-made), and containers (Tyvek, zipper bags). In the second experiment, different numbers of air holes (16, 32, 48 holes) in zipper bags experiment is ongoing. The results indicated that the larvae development rate was 72.6%, 69.98%, and 55.33% in 10, 20, and 30 larvae densities, respectively. However, there was no significant difference in larvae survival rate and weight. In the different feed material experiments, the average larvae weight of commercial feed was 1.09g and for self-made, it was 2.85g. The survival rate was 86% and 96% in commercial and self-made feed, respectively. Lastly, while 96% of larvae survived in Tyvek bags, none of the larvae survived in the zipper bags.

Due to stricter environmental regulations of the International Maritime Organization (IMO), the number of ships fueled by Liquefied Natural Gas (LNG) is rapidly increasing. The International Code of the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) limits the material of tanks that can store cryogenic substances such as LNG. Among the materials listed in the IGC Code, ASTM A553M-17 has been recently adopted as a material for LNG fuel tank projects because of its excellent mechanical properties at cryogenic temperatures. In shipyards, this material is being used to build tanks through Flux Cored Arc Welding (FCAW). However, there is a problem that magnetization occurs during welding and there is a big difference in welding quality depending on the welding position. In order to overcome this problem, this study intends to conduct basic research to apply laser welding to ASTM A553M-17 material. As a result of analyzing the bead shape according to laser BOP speed and Energy density performed in this study, it was confirmed that the penetration and energy density are proportional but the penetration and BOP speed are inverse proportional to some extent. In addition, a range of suitable welding speed and energy density were proposed for the 6.1mm thickness material performed in this study.

The total energy and strength of Mg alloy doped with Al, Ca and Zn, were calculated using thedensity functional theory. The calculations was performed by two programs; the discrete variational Xα (DV-Xα) method, which is a sort of molecular orbital full potential method; Vienna Ab-initio Simulation Package(VASP), which is a sort of pseudo potential method. The fundamental mixed orbital structure in each energylevel near the Fermi level was investigated with simple model using DV-Xα. The optimized crystal structurescalculated by VASP were compared to the measured structure. The density of state and the energy levels ofdopant elements was discussed in association with properties. When the lattice parameter obtained from thisstudy was compared, it was slightly different from the theoretical value but it was similar to Mk, and weobtained the reliability of data. A parameter Mk obtained by the DV-Xα method was proportional toelectronegativity and inversely proportional to ionic radii. We can predict the mechanical properties becauseis proportional to hardness.

본 연구는 멀칭재료와 재식방법에 따른 shallot의 생육에 미치는 영향을 조사하였다. 멀칭비닐 종류별 시험에서 투명 PE필름 처리구에서 흑색 PE필름보다 엽수, 초장, 엽초장, 엽초경이 더 좋았고, 상품수량도 21%나 증수되었다. 그러나 구의 크기별 분포에서는 유의적인 차이가 없었다. Shallot의 재식밀도별 수량은 120 cm 5조(10 a당 20,833주)에서 1,332 kg으로 120 cm 2조(10 a당 12,500주)에서보다 1.7배가 증수되어 밀식재배가 유리하였다. 따라서 shallot의 재배는 투명 PE필름 멀칭에 휴폭 120 cm에 5조가 좋을 것으로 사료된다.

본 연구의 목적은 저열 시멘트를 활용한 콘크리트와 고밀도 폴리에틸렌을 활용한 친환경 저수조를 평가하는 것이다. 친환경 저수조의 강도와 파괴모드를 평가하기 위하여 콘크리트와 고밀도 폴리에틸렌 복합체의 인장강도 시험, 다양한 종류의 콘크리트 수화열 실험, 다양한 혼화재를 활용한 수화열 실험 등을 수행하였다. 수행결과 전단키가 콘크리트와 고밀도 폴리에틸렌의 복합체로 거동할 수 있는 중요한 역할을 한다는 것을 규명하였고, ㄱ 타입의 전단키가 V 타입보다 40% 이상 인장강도를 증진시킨다는 것을 보여주었다. 연구결과 새로운 친환경 저수조는 기존의 콘크리트 저수조보다 안전성을 개선시키며, 보다 적용성과 활용성이 많은 것으로 기대된다.