For application in nuclear decommissioning, underwater laser cutting studies were conducted on thick stainless-steel plates for various cutting directions using a 6 kW fiber laser. For cutting along the horizontal direction with horizontal laser irradiation, the maximum cutting speed was 110 mm∙min−1 for a 48 mm thick stainless-steel plate. For cutting along the vertical direction with horizontal laser irradiation, a maximum speed of 120 mm∙min−1 was obtained for the same thickness, which confirmed that the cutting performance was similar but slightly better. Moreover, when cutting with vertically downward laser irradiation, the maximum cutting speed was 120 mm∙min−1 for a plate of the same thickness. Thus, the cutting performance for vertical irradiation was nearly identical to that for horizontal irradiation. In conclusion, it was possible to cut thick stainless-steel plates regardless of the laser irradiation and cutting directions, although the assist gas rose up due to buoyancy. These observations are expected to benefit laser cutting procedures during the actual dismantling of nuclear facilities.

Climate change effects are particularly apparent in many cool-season grasslands in South Korea. Moreover, the probability of climate extremes has intensified and is expected to increase further. In this study, we performed climate change vulnerability assessments in cool-season grasslands based on the analytic hierarchy process method to contribute toward effective decision-making to help reduce grassland damage caused by climate change and extreme weather conditions. In the analytic hierarchy process analysis, vulnerability was found to be influenced in the order of climate exposure (0.575), adaptive capacity (0.283), and sensitivity (0.141). The climate exposure rating value was low in Jeju-do Province and high in Daegu (0.36–0.39) and Incheon (0.33–0.5). The adaptive capacity index showed that grassland compatibility (0.616) is more important than other indicators. The adaptation index of Jeollanam-do Province was higher than that of other regions and relatively low in Gangwon-do Province. In terms of sensitivity, grassland area and unused grassland area were found to affect sensitivity the most with index values of 0.487 and 0.513, respectively. The grassland area rating value was low in Jeju-do and Gangwon-do Province, which had large grassland areas. In terms of vulnerability, that of Jeju-do Province was lower and of Gyeongsangbuk-do Province higher than of other regions. These results suggest that integrating the three aspects of vulnerability (climate exposure, sensitivity, and adaptive capacity) may offer comprehensive and spatially explicit adaptation plans to reduce the impacts of climate change on the cool-season grasslands of South Korea.

This research is conducted to analyze the compatibility of used monomers and produce the high functional hydrogel ophthalmic polymer containing silane and nanoparticles. VTMS (vinyltrimethoxysilane), TAVS [Triacetoxy(vinyl)silane] and cobalt oxide nanoparticles are used as additives for the basic combination of SilM (silicone monomer), MMA (methyl methacrylate) and MA (methyl acrylate). Also, the materials are copolymerized with EGDMA (ethylene glycol dimethacrylate) as cross-linking agent, AIBN (thermal polymerization initiator) as the initiator. It is judged that the lenses of all combinations are optically excellent and thus have good compatibility. Measurement of the optical and physical characteristics of the manufactured hydrophilic ophthalmic polymer are different in each case. Especially for TAVS, the addition of cobalt oxide nanoparticles increases the oxygen permeability. These materials are considered to create synergy, so they can be used in functional hydrogel ophthalmic lenses.

본 연구는 관상가치가 뛰어난 산꼬리풀의 분화 재배법을 확립하고자 차광, 기비, 추비, 왜화제 및 적심처리를 각각 달리하여 수행하였다. 연구의 결과 차광 시 산꼬리풀의 생육이 감소 하였으며, 차광률이 증가할수록 크게 억제되었다. 기비 처리는 초장, 절간장, 경직경 및 엽수를 유의적으로 증가하였으나, Hyponex를 이용한 추비 처리는 무처리와 비교했을 때 생육증가에 큰 영향을 미치지 않았다. 왜화제 처리시 diniconazole은 농도에 관계없이 왜화효과가 나타났으며, 농도가 증가할수록 크게 억제되었다. Daminozide는 저농도 처리시 무처리와 비교하여 큰 차이가 없었으나, 2000mg·L-1 농도로 처리하였을 때 왜화효과가 나타났으며, 개화율은 diniconazole 저농도에서 가장 낮은 결과를 보였다. 한편 적심 처리에 따른 유의적인 생육 차이는 확인되지 않았다.