• EDISON SW 활용 경진대회 논문집
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• 제1회(2012년)
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• pp.69-72
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• 2012

본 연구에서는 정사각형으로 모델링된 실린더 주위에 균일한 유동이 흐를 때 나타나는 이차원 난류 유동을 분석하였다. EDISON-CFD를 이용하여 정사각 실린더 표면에서의 전단응력 분포 및 유동 현상을 시뮬레이션 하였다. 선행 연구 결과의 $\bar{C_D}$, ${C_L}^{\prime}$ 값과 비교하여 결과의 유효성을 검증하였다. 또한, 비정상 층류 유동(Re=100)과 비교하여 난류 유동(Re=22,000)의 특성을 분석하였고, 와 흐름에 의하여 정사각 실린더 표면이 받는 전단응력을 자세히 분석하였다.

• 한국환경생태학회:학술대회논문집
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• 한국환경생태학회 2003년도 추계학술논문발표회 논문집
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• pp.1-21
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• 2003

I introduce the Flexible Dam Operation (FDO) and some of sediment control techniques In dams which are implemented as trials to avoid or reduce environmental impact of dams on the downstream reaches. The FDO is a dam management method to improve river environment in the downstream reaches by means of the flushing flow, the maintenance flow and so on utilizing a vacant portion of capacity for flood control without interrupting prime flood control function during the rainy/typhoon season. It Is suggested by the guideline of the FDO that EDO should be implemented regularly after the trial for about three years. The basic conception of the FDO is described here. The example of excavation of deposited sediments in check dams and placement of sand ana gravel immediately downstream of the dams and the example of coordinated sediment flushing are described as some of sediment control techniques in dams. Now they are at the stage of experiment and trial. Therefore, it is important to increase examples and establish the technical methodology and the environmental evaluation method for them.

• 대한전자공학회논문지
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• 제4권3호
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• pp.2-8
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• 1967

불완전하게 규제된 순서회로의 내부상태를 간단화하는 방법을 논하였다. 본논문의 간단화절차는 원흐름표의 내부상태를 피복하는 최대병립유집합을 거점으로 하여 세 규칙을 적용하여 직접 극소피복을 얻는 것이다. P.I.표나 C.C표에 의한 간단화방법은 이를 채택하지 않았다. 본논문에서는 몇가지 문제에 대하여 간단화방법을 적용할 수 있는 것으로 믿는 바이다.

• Journal of Nutrition and Health
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• 제52권6호
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• pp.515-528
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• 2019

본 연구는 괭생이 모자반 추출물의 추출방법에 따른 면역증강활성에 관하여 비교 관찰하였고, 추출물간의 혼합비율을 다르게 혼합하여 제조한 괭생이 모자반 추출물의 최적 면역활성을 갖는 혼합비를 평가하였다. 비장세포에 괭생이 모자반 열수 (HWE), 주정 (EE), 초임계 (SFE) 추출물을 각각 처리하였을 때 HWE 및 SFE 처리구에서 비장세포 증식능 및 사이토카인 (IL-2, IFN-γ) 분비능이 높게 나타나는 것으로 관찰되었고, 각각의 추출물을 50, 100 mg/kg BW의 농도로 2주간 마우스에 투여하고 비장을 적출하여 비장세포 활성능에 관하여 관찰한 결과, HWE 및 SFE 투여구에서 비장세포 증식능 및 사이토카인 분비능이 높게 나타나는 것으로 관찰되었다. 동물실험에서 높은 활성을 보인 HWE와 SFE의 추출물의 혼합 최적비를 평가하기 위하여 HWE에 SFE를 5, 10, 15 및 20%로 혼합하여 대식세포에 처리하여 NO 및 사이토카인 분비능에 관하여 관찰한 결과, SFE를 5%, 10% 혼합한 추출물 처리구에서 활성이 높게 나타나는 것으로 관찰되었으며 혼합추출물을 100 mg/kg BW으로 14일간 투여한 마우스의 비장세포 활성에 관하여 관찰한 결과, SFE를 5%의 비율로 혼합한 추출물 처리구 비장세포 활성이 높게 나타나는 것으로 관찰되어 HWE와 SFE의 최적 혼합 비율을 HWE에 SFE를 5% 첨가하는 것으로 결정하였다. 결정된 최적혼합비로 100 mg/kg BW의 농도로 14일간 투여한 마우스의 비장세포에서 NK 세포를 분리하여 NK 세포의 활성능을 평가한 결과, 대조구 대비 높게 증가하는 것으로 나타났다. 따라서 괭생이 모자반 추출물을 최적비율로 혼합하여 제조한 혼합추출물은 비장세포, 대식세포 및 NK 세포에 대한 높은 활성능을 나타내어 면역증진에 기여하는 것으로 판단된다.

• 한국가구학회지
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• 제29권1호
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• pp.1-7
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• 2018

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Metasequoia glyptostroboides, diffuse-porous wood Anthocephalus cadamba and ring-porouswood Fraxinus rhynchophylla. In radial direction, ray cells and in longitudinal direction, tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of Metasequoia glyptostroboides was found the highest among all cells considered in Anthocephalus cadamba and Fraxinus rhynchophylla In radial direction, ray parenchyma of Metasequoia glyptostroboides was found the highest depth and the one of Fraxinus rhynchophylla was the lowest. The solution was penetrated lowest depth in the wood fiber of Fraxinus rhynchophylla. The large vessel of Fraxinus rhynchophylla was found the lowest depth among the vessels. The solutin was penetrated to the wood fiber of Anthocephalus cadamba higher than the one of Fraxinus rhynchophylla.

• 한국가구학회지
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• 제28권1호
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• pp.88-93
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• 2017

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Larix kaempferi (Lamb.)Carriere, diffuse-porous wood Betula davurica Pall.. and ring-porouswood Castanea crenata S.etZ. In radial direction, ray cells and in longitudinal direction, tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of Larix kaempferi was found the highest among all cells considered in Betula davurica and Castanea crenata, In radial direction, ray parenchyma of Larix kaempferi was found the highest depth and the one of Betula davurica was the lowest. The solution was penetrated lowest depth in the wood fiber of Castanea crenata. The large vessel of Castanea crenata was found the lowest depth among the vessels. The solutin was penetrated to the wood fiber of Betula davurica higher than the one of Castanea crenata.

• 수산해양기술연구
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• 제51권1호
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• pp.1-8
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• 2015

The common octopus, which has a high growth rate and high market price, is a prime candidate for commercial marine aquaculture operations. We evaluated the effectiveness of two types of shelters (pipe and tire types) for juvenile common octopus growing out in flow-through seawater tanks. Growth rates were evaluated in two experiments. The first experiment (Experiment 1) ran for 72 days, and the second (Experiment 2; replicated) ran for 46 days. Each trial included 40 octopuses fed a diet of frozen sardine (Sardinops melanostictus) and swimming crab (Portunustri tuberculatus) at 3-8% of body weight once every 3 days. In the two experiments, the respective specific growth rates were 0.3 and 0.04%/day in pipe-type shelters and 0.00 and 0.88%/day in tire-type shelters, while the respective percentage survivals were 80 and 80% in pipe-type shelters and 70 and 90% in tire-type shelters. Shelter type had little influence on the growth rate (P < 0.05).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2640-2642
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• 2005

Servovalves are widely used in industrial areas in order to control the position of large steam valves which regulate steam flow to prime mover. We must control the position of large steam valves to regulate flow of working fluids in the process. The small pilot valves are used to regulate the large main valves in case that the pressure of control fluids supplied to servovalves is low about $12kg/cm^2$. But, in case that the pressure of control fluids supplied to servovalves is high enough about $110kg/cm^2$, the pilot valves are not needed and servovalves can control directly the large main valves due to its large working forces. Additionally, the basic structures of armature coil should be different according to the types of control system even in the same servovalve. This paper compares and describes some integral types of flow control.

• 설비공학논문집
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• 제10권1호
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• pp.66-78
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• 1998

Adequate ventilation with the proper amount of air to the right place is important factor to achieve a good Indoor air climate. Thus it is of prime importance that the ventilation system is working properly. This requires reliable pressure loss calculation to balance the air flow through duct systems. So a computer program for balancing CAV duct system is developed In this study. The results of CAV duct system is compared with the "Balans" code developed by Larsen from Norway. To obtain the pressure drop characteristics of damper at duct terminal, some experiments are performed using DPM(Dual Pressure Measurement) system. To adjust the resistance of damper, present study suggests that some special diffusers should be designed and damper producers should give the data of air flow vs. pressure drop to the customs when they manufacture the damper. One of the results concludes that the working time can be reduced from several minutes to several seconds per damper in the present experimental site, if the DPM system and the air volume adjusting process are used.

• 대한토목학회논문집
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• 제5권3호
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• pp.145-159
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• 1985

교통류(交通流)의 특성(特性)을 이해(理解)하는데도 속도(速度), 밀도(密度), 차두시간(車頭時間) 및 교통량(交通量)의 상관성(相關性)이 매우 중요(重要)하다. 설계(設計)의 기본(基本)이나 교통운용면(交通運用面)에서도 적정수준의 공용성(供用性) 제공(提供)하는 데도 관련이 깊다. 결국(結局) 교통류(交通流)의 특성(特性)을 개량(改良)할 목적(目的)으로 도로(道路)와 교통(交通)과의 상호기능(相互機能) 개발에 대한 앞으로의 노력(勞力)은 역시 현재(現在)의 교통현상(交通現象)을 중요시(重要視)해야 한다. 이 논문(論文)은 이러한 실측자료(實測資料)를 토대로 하여 교통류(交通流)의 특성(特性)을 통계적(統計的)으로 해석(解析)하고 교통량(交通量) 산정(算定)을 위한 적정 Model 식(式)을 제안(提案)하였다.