• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2682-2695
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• 2021

This paper aims to evaluate the structural dynamic responses and damage/failure of the nuclear fuel reprocessing plant under the free drop impact of spent fuel cask (SFC) and fuel assembly (FA) during the on-site transportation. At the present Part I of this paper, the large-scale SFC model free drop test and the corresponding numerical simulations are performed. Firstly, a composite target which is composed of the protective structure, i.e., a thin RC plate (representing the inverted U-shaped slab in the loading shaft) and/or an autoclaved aerated concrete (AAC) blocks sacrificial layer, as well as a thick RC plate (representing the bottom slab in the loading shaft) is designed and fabricated. Then, based on the large dropping tower, the free drop test of large-scale SFC model with the mass of 3 t is carried out from the height of 7 m-11 m. It indicates that the bottom slab in the loading shaft could not resist the free drop impact of SFC. The composite protective structure can effectively reduce the damage and vibrations of the bottom slab, and the inverted U-shaped slab could relieve the damage of the AAC blocks layer dramatically. Furthermore, based on the finite element (FE) program LS-DYNA, the corresponding refined numerical simulations are performed. By comparing the experimental and numerical damage and vibration accelerations of the composite structures, the present adopted numerical algorithms, constitutive models and parameters are validated, which will be applied in the further assessment of drop impact effects of full-scale SFC and FA on prototype nuclear fuel reprocessing plant in the next Part II of this paper.

• The Plant Pathology Journal
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• 제40권2호
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• pp.233-233
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• 2024

• 한국유기농업학회지
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• 제27권4호
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• pp.437-452
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• 2019

소규모 식육포장처리장은 일반규모 작업장에 비해 종업원의 숫자가 적기 때문에 전반적인 위생상태 개선 및 HACCP System의 적용을 위해서 일반 규모 작업장에 비해 간단히 적용할 수 있도록 해야 할 필요가 있는 것은 사실이다. 하지만 여전히 축산식품 안전사고가 많이 나타나고 있는 시점에 국민건강 안전을 위해서라도 식육포장처리장에서 많이 발생하는 문제점, 그리고 그 위해의 심각도가 커서 사회·경제적으로 파급 여파가 큰 중요 관리항목에 대해서는 규모가 작은 업소에서도 철저히 준수해야 할 필요가 있다고 판단되며, 이는 HACCP 심사에도 연계하여 그에 대한 평가를 진행할 필요가 있다고 사료된다. 본 연구결과 도출을 위해 지난 3년간의 HACCP 심사 시 지적사항 발생빈도를 분석하고, 기존 논문자료 등을 참고하여 중요도를 결정하여 새로운 소규모 HACCP 평가항목을 도출하였다. 다만, 본 연구에서 개발된 소규모 식육포장처리업 HACCP 평가항목은 통계적, 문헌적 자료를 검토하여 도출한 것으로 실제 소규모 식육포장처리장 작업 현장에서 꼭 평가가 필요한 항목인지에 대해서는 추후 현장적용을 통해 추가적인 검토가 필요할 것으로 사료되고, 현행 『식품 및 축산물 안전관리인증기준』 고시에 따른 일반규모 축산물 HACCP 평가는 업종별 특성에 맞추어 평가항목이 다르게 적용되어 있으나, 소규모의 경우에는 식육판매업 및 식용란수집 판매업을 제외한 다른 업종은 전부 동일한 평가표를 이용하여 평가를 하도록 되어 있어 해당 업종의 특성에 맞도록 평가항목을 분리하는 등의 연구도 필요할 것으로 판단된다. 아울러 인력 부족 등으로 인하여 소규모 식육포장처리장에서 쉽게 적용하기 어려운 위해분석 등 HACCP 관리 평가항목에 대해서는 정부에서 쉽게 적용할 수 있는 모델 개발 등을 통해 소규모 식육포장처리장에서 무리 없이 HACCP을 적용할 수 있도록 유도하는 것이 중요한 것으로 판단된다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.139.1-139
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• 2003

Tissues from woody plant contain higher amount of phenolic compounds and polysaccharides, which give inhibitory effects on reverse transcriptase and/or Taq ploymerase. The common multiple-step protocols using several additives to inhibit polyphenoic compounds during nucleic acid extraction are time consuming and laborious. Sodium sulfite (Na$_2$SO$_3$) was used as inhibitor of polyphenolic oxidases in extraction buffer and compare it's effect between commercial RNA extraction kit and small-scale double-stranded RNA (dsRNA) extraction by RT-PCR. During nucleic acid extraction procedure, addition of 0.5％-1.5％ (w/v) sodium sulfite to Iysis buffer or STE buffer resulted in lighter color change than extracts without sodium sulfite and improve the RT-PCR detection. When commercial RNA extraction kit used, optimal concentration of sodium sulfite were variable according to the host plant. However, using dsRNA as RT-PCR template, 1.5％ sodium sulfite in STE buffer improves the detection of both viruses and unspecific amplifications were reduced significantly, Furthermore, when viruses existed at low titers in host plant, small-scale dsRNA extractions were very reliable.

• 상하수도학회지
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• 제21권5호
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• pp.581-587
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• 2007

In order to suggest the methodology for improving the equality of flow distribution in a distribution channel, wet tests were carried out for pilot plant which was scaled down to 1/8 of full scale distribution channel being operated in domestic K_water treatment plant. The correlation between various hydraulic variables and their effects on the equality of flow distribution was evaluated through wet tests using pilot plant. From the results of wet tests, the longitudinal baffle with orifices was installed in the distribution channel, the equality of flow distribution was improved on the condition that the Froude number in pilot plant was similar with that in the full scale channel. Also, the opening ratio of the orifices on the longitudinal baffled did not have influence on the performance of the equality of flow distribution when the average flow velocity and Froud number were relatively low (Froude number ${\fallingdotseq} 0.01$). In the other hand, the performance of the equality of flow distribution was improved with increasing the opening ration of on the longitudinal baffle under conditions of relatively high average flow velocity and high Froud number(${\gtrsim}0.1$)

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.176-179
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• 2000

Nonpolar taxoides extracted from a large-scale cell culture of Taxus chinensis were isolated through the normal and reverse phase column chromatographies, and their compounds were identified via NMR spectroscopy. The complete separation method was systematically established and described. In dichloromethane, dissolved paclitaxel and other taxoids with hexane were precipitated during the purification of paclitaxel from the plant cell culture of T. chinensis through a large-scale process while the relatively nonpolar taxane derivatives remained dissolved in the hexane phase. 13-Deoxy baccatin III (I), baccatin VI (II), taxchinin I (III), $2{\alpha}$, $5{\alpha}$, $10{\beta}$, $14{\beta}$-tetraacetoxy-4(20), 11-taxadiene(IV), 1-deoxy baccatinVI(V), and taxayuntin C (VI) were isolated through column chromatography and identified via NMR spectroscopy. Compounds I and IV were found to the major components, aside from paclitaxel, in the plant cell culture of T. chinensis. The concentrations of I and IV were compared with the that concentration of the paclitaxel in each of plant cell culture. The possible applications of compounds I, II, IV, and V were discussed.

• Journal of Computational Design and Engineering
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• 제1권1호
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• pp.13-26
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• 2014

Recently, renovations of plant equipment have been more frequent because of the shortened lifespans of the products, and as-built models from large-scale laser-scanned data is expected to streamline rebuilding processes. However, the laser-scanned data of an existing plant has an enormous amount of points, captures intricate objects, and includes a high noise level, so the manual reconstruction of a 3D model is very time-consuming and costly. Among plant equipment, piping systems account for the greatest proportion. Therefore, the purpose of this research was to propose an algorithm which could automatically recognize a piping system from the terrestrial laser-scanned data of plant equipment. The straight portion of pipes, connecting parts, and connection relationship of the piping system can be recognized in this algorithm. Normal-based region growing and cylinder surface fitting can extract all possible locations of pipes, including straight pipes, elbows, and junctions. Tracing the axes of a piping system enables the recognition of the positions of these elements and their connection relationship. Using only point clouds, the recognition algorithm can be performed in a fully automatic way. The algorithm was applied to large-scale scanned data of an oil rig and a chemical plant. Recognition rates of about 86%, 88%, and 71% were achieved straight pipes, elbows, and junctions, respectively.

• Journal of Advanced Marine Engineering and Technology
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• 제39권10호
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• pp.1037-1043
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• 2015

In recent years, Floating Liquefied Natural Gas (FLNG) Unit have attracted considerable attention. Generally, liquefied natural gas (LNG) units are produced in onshore liquefaction terminals from gas supplied from onshore gas fields or large-scale offshore gas fields near the coast. However, the development of these gas fields has approached saturation. Large-scale offshore gas fields far from the coast, as well as undeveloped medium- and small-scale offshore gas fields, have recently attracted attention. Among several proposed concepts, the floating LNG plant in the form of the FLNG system was chosen for further evaluation and development, considering worldwide receiving infrastructure. The design of a 2.5 million tonne per annum FLNG unit has been completed with a capacity corresponding to that of modern onshore liquefaction plants. Various simulation tests were performed to evaluate the performance of the electrical power plant, focusing on the efficiency of the electrical system to secure the aspects of plant safety. This design study analyzes the electrical system for the FLNG unit to improve the safety of operation and maintenance in the field.

• 한국초전도ㆍ저온공학회논문지
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• 제23권3호
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• pp.14-19
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• 2021

The reduction of carbon dioxide emissions becomes a global issue, the main source of carbon dioxide emissions in the Asian region is the energy conversion sector, especially coal-fired power plants. We are working to develop technologies that will at least limit the increase in carbon dioxide emissions from the thermal power plants as one way to reduce carbon dioxide emissions. Our research aims to reduce carbon dioxide emissions by removing iron oxide scale from the feedwater system of thermal power plants using a superconducting high-gradient magnetic separation (HGMS) system, thereby reducing the loss of power generation efficiency. In this paper, the background of thermal power plants in Asia is outlined, followed by a case study of the introduction of a chemical cleaning line at an actual thermal power plant in Japan, and the possibility of introducing it into the thermal power plants in China based on the results.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2003년도 추계 학술발표회 요지
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• pp.142-143
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• 2003