Laser cutting technology capable of remote cutting is being developed to reduce radiation exposure to workers and minimize secondary waste generation when dismantling highly polluted nuclear power plant facilities (reactors, pressurizers, steam generators, coolant pumps, etc.). Laser cutting proceeds in air or water, and at this time, secondary products containing radioactive materials are inevitably generated. In air cutting, dust and aerosol are generated, and in underwater cutting, aerosol, water vapor, dispersed particles (colloid, suspension), sediment (dross, sediment), and radioactive waste liquid are generated. Dispersed particles float in the form of fine particles in water, increasing the turbidity of water as cutting progresses, hindering work, and aerosols contain micrometer-sized particles together with water vapor, which can threaten the safety of workers. Particles dispersed in water and aerosol are within 10% of the mass ratio among secondary products, but the volume they occupy is very large, which can have a significant impact on the environment as well as a burden on treatment capacity. Various characterization methods are being developed to diagnose the generation mechanism and physical and chemical properties of laser cutting secondary products in real time and to secure technologies for collecting and removing dispersed particles and aerosols in water. This study introduces a real-time laser cutting secondary product characteristic evaluation method that can identify the key mechanisms of secondary product generation by analyzing the plasma formation process on laser cutting surface and behavior of aerosol, underwater dispersed particles produced by secondary products, as well as physical and chemical properties in real time with various measurement technologies such as Optical Emission Spectrometer (OES), Particle Size Analyzer (PSA), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDX), Transmission electron microscopy (TEM) and Inductively Coupled Plasma Time-of-Flight Mass Spectrometry (ICP-TOF-MS).

최근 국내에서는 월성 1호기 및 고리 1호기를 포함하여 운영 중인 원자력발전소가 노후화함에 따라 원전 해체에 대한 관심 이 많이 증대되고 있다. 이와 관련하여 월성 1호기의 계속운전이 최근 결정되었으며, 고리 1호기의 경우 2017년 6월 영구정 지하기로 결정되었다. 이에 본 논문에서는 상업용 원자로로서는 국내 최초로 해체가 예정된 고리 1호기에 대해, 원자로 압 력용기 자체의 해체로 인해 발생하는 방사성폐기물 최종 처분량을 원자로 압력용기 절단 방법 및 방사성폐기물 처분용기를 고려하여 산정하였다. 처분용기를 고려한 방사성폐기물 처분량을 산정한 결과 원자로 압력용기 몸통 부위보다는 반구 형태 의 헤드 부분을 작게 절단할수록 최종 처분량이 감소하는 것으로 예측되었다. 또한 경주 방폐장의 200 L 및 320 L 드럼 처분 용 처분용기의 경우 무게 제한으로 인해 적재효율이 좋지 못한 것으로 나타났다.

허브 식물을 조경소재로 이용할 수 있도록 삽목방법, 토심 및 품종에 따라 뗏장형성에 미치는 영향을 알아 보고자 1cm, 3cm, 5cm의 토심별로 천삽, 와삽, 절와삽을 한 다음 애플민트, 페퍼민트, 스피어민트 등 세품종을 재료로초장과 마디수, 생체중, 뗏장의 품질을 조사한 결과 세 품종 중 애플민트는 신초의 수는 적으나 엽장, 엽폭이 크기 때문에 피복률이 좋고 생장속도도 빨라서 빠른 시기에 뗏장(sod)형성이 가능하였다. 스피어민트는 초장이 작고 발육속도가 느리기 때문에 뗏장의 이동성, 저장성면에서 양호하였다. 삽목 방법은 천삽에서 생육이 가장 좋았으나 뗏장 품질은 가장 낮았으며 절와삽은 초장이 작고 신초수가 많아 고품질의 뗏장을 생산할 수 있었다. 토심별로 본 생육의 차이는 5cm의 상토에서 재배한 것이 가장 높게 나타났고 뗏장의 품질과 이동성은 1cm의 상토에서 밀착되어 있어 근권부의 뗏장형성이 좋은 것으로 나타났다.

Whole apples were cut with a sharp or dull knife, and whole cabbages and crisp lettuce heads were cut into salad or thin strips with a knife or by hand. The fresh-cut apples, cabbages, and lettuce were packed in low-density polyethylene bags and kept at 4°C, and their qualities were investigated. Browning and softening of the apples that were cut with a sharp knife were more delayed than those of the apples that were cut with a dull knife. The soluble solids and pH of the fresh-cut apples were not affected by the sharpness of the cutting blade. The browning indexes of the fresh-cut cabbages and lettuce were significantly lower in the samples that were cut with a knife than by hand and in the samples that were cut into large pieces. The results suggest that the cutting blade sharpness, cutting tools, and cut types affected the quality of the fresh-cut apples and leafy vegetables, and that the cutting methods which minimized the cutting damage should be used to retard the browning and softening of the produce