When decommissioning a nuclear power plant, the structure must be made to a disposable size. In general, the cutting process is essential when dismantling a nuclear power plant. Mainly, thermal cutting method is used to cutting metal structures. The aerosols generated during thermal cutting have a size distribution of less than 1 μm. The contaminated structures are able to generate radioactive aerosols in the decommissioning. Radioactive aerosols of 1 μm or less are deposited in the respiratory tract by workers’ breathing, causing the possibility of internal exposure. Therefore, workers must be protected from the risk of exposure to radioactive aerosols. Prior knowledge of aerosols generated during metal cutting is important to ensure worker safety. In this study, the physical and chemical properties of the aerosol were evaluated by measuring the number and mass concentrations of aerosols generated when cutting SUS304 and SA508 using the laser cutting method. High-resolution aerosol measuring equipment (HR-ELPI+, DEKATI) was used to measure the concentration of aerosols. The HR-ELPI+ is an impactor-type aerosol measuring equipment that measures the aerosol number concentration distribution in the aerodynamic diameter range of 6 nm to 10 um in real-time. And analyze the mass concentration of the aerosol according to the diameter range through the impactor. ICP-MS was used for elemental mass concentration analysis in the aerosol. Analytical elements were Fe, Cr, Ni and Mn. For the evaluation of physical and chemical properties, the MMAD of each element and CMAD were calculated in the aerosol distribution. Under the same cutting conditions, it was confirmed that the number concentration of aerosols generated from both materials had a uni-modal distribution with a peak around 0.1 um. CMAD was calculated to be 0.072 um for both SUS304 and SA508. The trend of the CMAD calculation results is the same even when the cutting conditions are changed. In the case of MMAD, it was confirmed that SUS304 had an MMAD of around 0.1 μm in size for only Fe, Cr and Mn. And SA508, Fe, Cr, Ni and Mn were all confirmed to have MMAD around 0.1 μm in size. The results of this study show that a lot of aerosols in the range of less than 1 μm, especially around 0.1 μm in size, are generated when metal is cut using laser cutting. Therefore, in order to protect the internal exposure of workers to laser metal cutting when decommissioning NPPs, it is necessary to protect from nano-sized aerosols beyond micron size.

루비깍지벌레 Ceroplastes rubens는 감귤에 피해를 주는 주요 깍지벌레 중 하나로 연 1회 발생하며 수액을 흡즙하는 직접적인 피해와 분비된 감로로 인한 그을음병 유발의 간접적인 피해가 발생하고 있다. 제주지역에서 루비깍지벌레 천적으로는 루비붉은깡충좀벌 Anicetus beneficus와 애홍점박이무당벌레 Chilocorus kuwanae 2종이 확인되었다. 1975년 일본에서 도입 방사한 천적인 루비붉은깡충좀벌이 현재까지 지속적으로 발생하고 있었으며, 루비깍지벌레 발생 억제에 영향을 미치고 있었다. 2018년 4월부터 12월까지 도내 유기재배 감귤원 (2개소)에서 황색끈끈이트랩을 이용 루비붉은깡충좀벌 성충의 시기별 발생양상을 조사한 결과 월동세대 성충은 5월 중순, 제1세대와 제2세대 성충은 각각 7월 중순과 8월 하순에 발생 정점을 나타내었다. 조사 포장에서 루비깍지벌레의 기생률은 9월 중순에 9.6%와 19.6%이었다.

The black pine bast scale are the main insects of the Japanese black pine forest in Korea, and the distribution is spreading around the Japanese black pine forest in the east and west coast. However, after the nationwide survey in 2010, there has been no investigation on the distribution and spread of these, so we conducted the 2017 and 2018 surveys to determine the extent of the northern area inland or east and west. In the 2017 survey, outbreaks were observed in 35 areas from 47 dong or myeon of 14 cities or counties, mainly in areas not previously located in the outbreak area. In the 2018 survey, additional outbreaks were confirmed at 14 out of 23 areas in the East Coast region, and damage was detected at 27 out of 28 points in the inland area of the South Sea and distribution was found at 16 out of 17 in the west coast.

From 2017 to 2018, the occurrence of leafhopper species in eight landscape trees (Acer palmatum, Elaeagnus umbellata, Lagerstroemia indica, Pinus densiflora, Prunus serrulata, Pseudocydonia sinensis, Rosa hybrid, Zelkova serrata) in Sangju, Gyeongbuk Province was investigated using flat traps from the leaf open season to the fallen season. E. rosae was the most abundant, and the highest density was observed in cherry trees. E. rosae outbreaks occurred at the end of March, early August, and early October, and are estimated to occur three generations a year. High attraction was observed in yellow plate traps than in blue. From the middle of October, the number of E. rosae increases only in Pinus densiflora among 8 species of trees, and it is estimated that pine trees are wintering places.

There are a lot of types of wild vegetables such as Colocasia esculenta (L.) Schott stem in Korea. However, the consumption of these wild vegetables is restricted because their storage decreased dramatically after harvest. To maintain original quality of vegetables, pre-treatments such as blanching and drying are important. But conditions for these treatments were still not optimized for many vegetables including Colocasia esculenta (L.) Schott stem. Thus, the objective of this study was to set up an optimal pre-treatment method for freezing storage. Colocasia esculenta (L.) Schott stems were peeled and cut equally (10 cm) for sample preparation. Dried samples (D) were dried at 90℃ for 3 h. Blanched samples (B) were blanched in hot water at 100℃ for 2 min. Blanched and dried samples (BD) were blanched and dried as same protocol. Physicochemical properties were analyzed to evaluate the quality including texture, moisture content, total color difference and viable cell count. Raw sample had 6.85 kg/cm 3 of hardness and 78.75 of chewiness whereas B was 6.83 kg/cm 3 of hardness and 7.8 of chewiness. B had the similar value compared to raw samples. Moisture content of raw sample was 94.4% and that of B was 94.1%, though there were not any significant differences between them. ΔE value of B showed lower value than those of the others. Viable cell counts and total coliforms were not detected after treatment, while raw sample had 5.39 log CFU/g of viable cell count without total coliform. Therefore, pre-treatments are essential for microbial safety of samples. All results considered, it is supposed that blanching is the optimal pre-treatment to sustain its original quality of Colocasia esculenta (L.) Schott stems before freezing.